1: J Nutr. 2003 Jul;133(7):22328.
Appropriate calcium fortification of the food supply presents a challenge.
JohnsonDown L, L'Abbe MR, Lee NS, GrayDonald K.
Fortification with calcium to increase dietary intakes of this mineral
is
currently under evaluation in Canada. To model the potential dietary
consequences of food fortification, data from a large national survey
of
Canadians (n = 1543) were used. Food fortification scenarios were based
on
reference amounts for labeling requirements. Consumption of milk, cheese
and
other dairy products was associated with high calcium intakes, and there
was a
low prevalence of inadequacy in men < 50 y old; however, other agesex
groups
had lower intakes. The aim of the fortification modeling was to determine
which
scenario would most effectively reduce the proportion of the population
with low
intakes of calcium while minimizing the proportion of individuals who
exceeded
the tolerable upper intake level (UL). Given the correlation between energy
and
calcium (r = 0.60, P < 0.01), it appeared that any fortification scenario
sufficient to increase the mean intake for women to near the adequate
intake led
to 67% of the men having calcium intakes above the UL. The results suggest
that
fortification of widely consumed foods is not a realistic way to address
the
issue of low calcium intakes and illustrate the need for concern about
the
growing use of fortification practices.
PMID 12840185
2: Am J Kidney Dis. 2003 Mar;41(3 Suppl 2):S1047.
Renal osteodystrophy: role of calcimimetics.
Horl WH.
In patients with secondary hyperparathyroidism (HPT), increased parathyroid
hormone (PTH) secretion is triggered by low plasma calcitriol levels,
hypocalcemia, and hyperphosphatemia. Vitamin D analogues have been used
successfully to reduce PTH levels, but increases in serum calcium, phosphorus,
and calcium x phosphorus ion product levels may occur. Secondgeneration
calcimimetics have been shown to suppress PTH levels and also reduce calcium
x
phosphorus ion product. Potential indications are patients with secondary
HPT,
particularly those who respond to calcitriol therapy with an increase
in calcium
x phosphorus ion product. Coadministration of active vitamin D compounds
may be
necessary to overcome intestinal malabsorption of calcium and maintain
normocalcemia in patients on longterm treatment with calcimimetics.
3: J Fam Pract. 2003 Mar;52(3):234, 237.
Do calcium supplements prevent postmenopausal osteoporotic fractures?
Campbell BG, Ketchell D, Gunning K.
Montana Family Practice Residency, Billings, MO, USA.
Calcium supplementation (10001200 mg daily) decreases menopauserelated
bone
loss and reduces the rate of vertebral and nonvertebral fractures. Calcium
is
more efficacious in conjunction with vitamin D (700800 IU daily), particularly
in elderly patients, who have a high rate of vitamin D deficiency.
PMID 12620181
4: S Afr Med J. 2003 Mar;93(3):2248.
Calcium supplementation to prevent preeclampsiaa systematic review.
Hofmeyr GJ, Roodt A, Atallah AN, Duley L.
BACKGROUND: Calcium supplementation during pregnancy may prevent high
blood
pressure and preterm labour. OBJECTIVE: To assess the effects of calcium
supplementation during pregnancy on hypertensive disorders of pregnancy
and
related maternal and child adverse outcomes. DESIGN: A systematic review
of
randomised trials that compared supplementation with at least 1 g calcium
daily
during pregnancy with placebo. SEARCH STRATEGY: The Cochrane Pregnancy
and
Childbirth Group trials register (October 2001) and the Cochrane Controlled
Trials Register (Issue 3, 2001) were searched and study authors were contacted.
DATA COLLECTION AND ANALYSIS: Eligibility and trial quality were assessed.
Data were extracted and analysed. MAIN RESULTS: There was a modest reduction
in the risk of preeclampsia with calcium supplementation (relative risk
(RR) 0.68, 95%
confidence interval (CI): 0.570.81). The effect was greatest for women
at high
risk of hypertension (RR 0.21, 95% CI: 0.110.39) and those with low baseline
calcium intake (RR 0.32, 95% CI: 0.210.49). There was no overall effect
on the
risk of preterm delivery, although there was a reduction in risk among
women at
high risk of hypertension (RR 0.42, 95% CI: 0.230.78). There was no evidence
of
any effect of calcium supplementation on stillbirth or death before discharge
from hospital. There were fewer babies with birthweight < 2,500 g (RR
0.83, 95%
CI: 0.710.98). In one study, childhood systolic blood pressure > 95th
percentile was reduced (RR 0.59, 95% CI: 0.390.91). CONCLUSIONS: Calcium
supplementation appears to be beneficial for women at high risk of gestational
hypertension and in communities with low dietary calcium intake. These
benefits
were confined to several rather small trials, and were not found in the
largest
trial to
5: Cancer Causes Control. 2003 Feb;14(1):112.
Calcium, vitamin D, dairy products, and risk of colorectal cancer in the
Cancer
Prevention Study II Nutrition Cohort (United States).
McCullough ML, Robertson AS, Rodriguez C, Jacobs EJ, Chao A, Carolyn J,
Calle
EE, Willett WC, Thun MJ.
OBJECTIVE: Calcium, vitamin D, and dairy product intake may reduce the
risk of
colorectal cancer. We therefore examined the association between these
factors
and risk of colorectal cancer in a large prospective cohort of United
States men
and women. METHODS: Participants in the Cancer Prevention Study II Nutrition
Cohort completed a detailed questionnaire on diet, medical history, and
lifestyle in 199293. After excluding participants with a history of cancer
or
incomplete dietary information, 60,866 men and 66,883 women remained for
analysis. During followup through 31 August 1997 we documented 421 and
262
cases of incident colorectal cancers among men and women, respectively.
Multivariateadjusted rate ratios (RR) were calculated using Cox proportional
hazards models. RESULTS: Total calcium intake (from diet and supplements)
was
associated with marginally lower colorectal cancer risk in men and women
(RR =
0.87, 95% CI 0.671.12, highest vs lowest quintiles, p trend = 0.02). The
association was strongest for calcium from supplements (RR = 0.69, 95%
CI
0.490.96 for > or = 500 mg/day vs none). Total vitamin D intake (from
diet and
multivitamins) was also inversely associated with risk of colorectal cancer,
particularly among men (RR = 0.71, 95% CI 0.510.98, p trend = 0.02). Dairy
product intake was not related to overall risk. CONCLUSIONS: Our results
support
the hypothesis that calcium modestly reduces risk of colorectal cancer.
Vitamin
D was associated with reduced risk of colorectal cancer only in men.
PMID 12708719
6: Clin Exp Rheumatol. 2003 JanFeb;21(1):1926.
Calcium, vitamin D and etidronate for the prevention and treatment of
corticosteroidinduced osteoporosis in patients with rheumatic diseases.
Loddenkemper K, Grauer A, Burmester GR, Buttgereit F.
INTRODUCTION: Longterm glucocorticoid therapy, a major risk factor for
the
development of osteoporosis, is often necessary in chronically ill patients.
At
present there are no generally accepted guidelines for the prevention
or
treatment of steroidinduced osteoporosis. METHODS: In an open prospective
study
we investigated 99 patients with chronic rheumatic diseases receiving
> or = 5
mg/day of prednisolone or the equivalent for at least one year. The objective
was to identify osteoporosis risk factors in addition to glucocorticoid
therapy
and to evaluate the efficacy of prevention with calcium/vitamin D (group
1patients with osteopenia) and treatment with cyclical etidronate (group
2patients with osteoporosis). Biochemical markers of bone turnover, clinical
parameters and bone mineral density (BMD) were measured. RESULTS: Increasing
age
and postmenopausal status were associated with more advanced manifestations
of
steroidinduced osteoporosis (p < 0.05). One year after the start of
therapy
parameters of bone metabolism increased significantly in group 1, while
BMD did
not change. In group 2, lumbar spine BMD increased significantly (p <
0.05)
whereas femoral neck BMD and bone metabolism parameters remained constant.
The
intensity of back pain decreased in both groups (p < 0.05). There were
fewer new
fractures in group 2 than in group 1. CONCLUSION: Treatment with etidronate
is
effective in patients with glucocorticoidinduced osteoporosis.
7: Wei Sheng Yan Jiu. 2003 Jan;32(1):813.
[Review of dietary risk factors for osteoporosis]
Wang P, Zhang H.
Dietary factors are convenient but correctable factors in the pathogenesis
of
osteoporosis. The peak bone mass in the young can be increased and the
rate of
bone loss in the elderly possibly be reduced by dietary manipulation,
which
would be important and beneficial in the prevention of osteoporosis. Dietary
risk factors for osteoporosis include low calcium intake, low or high
protein
intake, low vitamin intake, smoking, and high intake of alcohol, coffee,
carbonated beverage and salt.
8: J Trop Pediatr. 2002 Dec;48(6):3513.
Comparisons of oral calcium, high dose vitamin D and a combination of
these in the treatment of nutritional rickets in children.
Kutluk G, Cetinkaya F, Basak M.
Nutritional rickets remains a common child health problem in Turkey and
many
other developing countries. Although vitamin D deficiency is accepted
as the
basic problem underlying the disease, others postulate that a deficiency
of
dietary calcium, rather than vitamin D, is often responsible for the nutritional
rickets in sunny countries. We conducted a placebocontrolled study to
determine
the best treatment regimen for nutritional rickets in children residing
in lower
socioeconomic regions of a sunny city, Istanbul. Fortytwo infants (aged
630
months) with rickets were divided into three groups and included in the
study.
In a randomized fashion vitamin D (300 000 units, intramuscularly), calcium
lactate (3 g daily) or a combination of vitamin D and calcium were given
to the
children. Alkaline phosphatase, calcium, albumin, ionized calcium and
phosphorus
levels were measured each week. Xray examinations of the left wrist and
left
knee were undertaken at the beginning of the study and were repeated at
the 2nd
and 4th weeks and were scored in order to assess the response to treatment.
Treatment produced an increase in serum calcium and a decrease in alkaline
phosphatase concentration in all three groups, but the most important
increase
was reached in the vitamin D plus calcium group. We conclude that vitamin
D
deficiency appears to be the primary etiologic factor of rickets in our
study
group, but a better response to treatment with vitamin D or in combination
with
calcium was obtained than to treatment with calcium alone.
9: Urol Nurs. 2002 Dec;22(6):4059.
OsteoporosisPart II: Dietary and/or supplemental calcium and vitamin D.
Moyad MA.
Osteoporosis is a significant problem in women and men. As osteoporosis
has
garnered more attention there seems to be more attention than ever placed
on the
potential benefits of calcium and vitamin D. Health professionals need
to inform
patients that there are numerous healthy dietary sources of calcium and
vitamin
D. Several forms of calcium supplements are commercially available today
and
health professionals need to understand the similarities and differences
between
them. Calcium and vitamin D in moderation also have an excellent safety
profile
and may actually have benefits far beyond osteoporosis therapy.
PMID 12593233
10: Dtsch Med Wochenschr. 2002 Oct 25;127(43):22512.
[Disease prevention by vitamins and trace elements]
Pfeiffer AF, Einig Ch.
SUMMARY: Vitamins and trace elements are largely provided by a balanced
nutrition. In industrialized countries, though, frequent deficiencies
occur e.g.
in folic acid and vitamin D as well as iodide, iron and calcium. A short
review
of recommended daily intake is presented.
PMID 12397538
11: Eur J Clin Invest. 2002 Sep;32(9):6939.
Calcium affects biomarkers of colon carcinogenesis after right hemicolectomy.
van Gorkom BA, van der Meer R, Karrenbeld A, van der Sluis T, Zwart N,
Termont
DS, Boersmavan Ek W, de Vries EG, Kleibeuker JH.
BACKGROUND: In Western societies colonic cancer most frequently develops
in the
distal colon, largely as a result of the composition of the diet. Modulation
of
dietary factors is therefore an attractive modality to reduce colorectal
cancer
risk. This study aims to evaluate the potentially protective effects of
calcium
in right hemicolectomy patients. MATERIALS AND METHODS: A randomized controlled
crossover intervention trial was performed with 1000 mg of elemental calcium
per day for 2 months in 15 right hemicolectomy patients. Primary endpoints
were
proliferative activity, determined by immunohistochemical detection of
BrdUlabeled cells (LI) in rectal biopsies, and cytotoxicity and alkaline
phosphatase activity of faecal water. Secondary endpoints were bile acid
composition in faeces. RESULTS: Calciumreduced LI in the superficial onethird
of the crypt (from 0.84 +/ 0.27% to 0.37 +/ 0.08%, P = 0.04) and a trend
towards a lower total LI and LI in the mid onethird of the crypt was observed.
Alkaline phosphatase activity was reduced from 6.2 +/ 2.6 U mL1 in the
placebo
period to 4.6 +/ 2.2 in the calcium period (P = 0.02), and a trend toward
a
lower cytotoxicity of faecal water was observed. No effect on total bile
acids
in faeces was observed, but calcium increased the percentage of deoxycholic
acid
(from 49.6 +/ 7.0% to 56.5 +/ 6.2%, P = 0.03) and decreased the percentages
of
cholic acid (from 10.3 +/ 4.7% to 5.8 +/ 2.7%, P = 0.05) and lithocholic
acid
(from 26.7 +/ 3.4% to 23.9 +/ 2.9%, P = 0.04). CONCLUSION: Calcium may
have a
protective effect against colorectal cancer risk in right hemicolectomy
patients.
12: Am J Epidemiol. 2002 Jul 15;156(2):14857.
Association of dairy products, lactose, and calcium with the risk of ovarian
cancer.
Goodman MT, Wu AH, Tung KH, McDuffie K, Kolonel LN, Nomura AM, Terada
K, Wilkens LR, Murphy S, Hankin JH.
Epidemiologic findings have been inconsistent regarding the association
of
dietary fat, dairy products, and lactose with risk of ovarian cancer.
The
authors conducted a casecontrol study in Hawaii and Los Angeles, California,
to
examine several dietary hypotheses regarding the etiology of ovarian cancer
in a
population with a broad range of dietary intakes. A total of 558 patients
with
ovarian cancer diagnosed in 19931999 and 607 controls were interviewed
regarding their diet. Consumption of all dairy products, all types of
milk, and
lowfat milk, but not consumption of whole milk, was significantly inversely
related to the odds of ovarian cancer. Similar inverse gradients in the
odds
ratios were obtained for intakes of lactose and calcium, although these
nutrients were highly correlated (r = 0.77). The odds ratio for ovarian
cancer
was 0.46 (95% confidence interval: 0.27, 0.76) among women in the highest
quartile of dietary calcium intake versus the lowest (p for trend = 0.0006).
The
significant dietary association was limited to dairy sources of calcium
(p for
trend = 0.003), although a nonsignificant inverse gradient in risk was
also
found in relation to calcium supplement intake. These results suggest
that
intake of lowfat milk, calcium, or lactose may reduce the risk of ovarian
cancer.
PMID 12117706
13: Transfusion. 2002 Jul;42(7):93546.
Controlled study of citrate effects and response to i.v. calcium administration
during allogeneic peripheral blood progenitor cell donation.
Bolan CD, Cecco SA, Wesley RA, Horne M, Yau YY, Remaley AT, Childs RW,
Barrett
AJ, Rehak NN, Leitman SF.
BACKGROUND: Leukapheresis procedures are generally performed at citrate
anticoagulation rates extrapolated from shorter plateletpheresis procedures.
However, neither the metabolic effects nor the management of associated
symptoms
have been critically evaluated during leukapheresis in healthy donors.
STUDY
DESIGN AND METHODS: Symptom assessments (n = 315) and laboratory analyses
(n = 49) were performed during 244 procedures performed with and 71 without
prophylactic calcium (Ca) chloride or Ca gluconate given at a dose linked
to the
citrate infusion rate (1.02.2 mg/kg/min). RESULTS: During leukapheresis
of 12
to 25 L processed, ionized Ca and ionized magnesium (Mg) decreased as
much as 35
and 56 percent, respectively, each exhibiting a tight negative correlation
with
marked increases in serum citrate levels. Significant increases in urinary
Ca
and Mg excretion accompanied the renal excretion of a large citrate load.
Serum
divalent cation levels remained depressed 24 hours after leukapheresis.
Symptoms
were more frequent in donors who were women, had low initial total Mg
levels,
and underwent procedures in which larger volumes were processed at higher
citrate infusion rates. Ca infusions reduced clinically significant paresthesias
by 96 percent and also attenuated decreases in serum potassium. Ca chloride
maintained higher Ca levels than Ca gluconate. CONCLUSIONS: Prophylactic
Ca
infusions safely attenuate the marked metabolic effects of citrate
administration and promote faster, more comfortable, leukapheresis procedures.
14: Toxicology. 2002 Jun 14;175(13):24755.
Calcium supplementation during lactation blunts erythrocyte lead levels
and
deltaaminolevulinic acid dehydratase zincreactivation in women nonexposed
to
lead and with marginal calcium intakes.
Pires JB, Miekeley N, Donangelo CM.
The purpose of this study was to evaluate the effect of calcium supplementation
during lactation on changes in blood lead indices from late pregnancy
to early
lactation in women with low calcium intakes and low leadexposure. Fortyseven
women, nonoccupationally exposed to lead and with habitually low calcium
intake
( approximately 600 mg/d), participated in the study from 29 to 38 weeks
of
pregnancy to 78 weeks postpartum, nonsupplemented (n=25) and supplemented
(n=22) with calcium (500 mg/d) during 6 weeks after delivery. Erythrocyte
lead
(PbRBC) and in vitro reactivation with zinc of blood deltaaminolevulinic
acid
dehydratase (ZndeltaALAD% reactivation) were used as lead indices. In
the
nonsupplemented group, PbRBC and ZndeltaALAD% reactivation increased
significantly (P<0.001) from pregnancy (0.202+/0.049 microg Pb/g protein
and
18.3+/6.0%) to lactation (0.272+/0.070 microg Pb/g protein and 22.7+/6.2%).
No significant changes of these indices were observed in the
calciumsupplemented group from pregnancy (0.203+/0.080 microg Pb/g protein
and
15.8+/4.5%) to lactation (0.214+/0.066 microg Pb/g protein and 16.3+/4.1%).
PbRBC levels and ZndeltaALAD% reactivation at lactation were lower (P<0.05)
and hematocrit levels were higher (P<0.05) in the calciumsupplemented
compared
to the nonsupplemented women. Calcium supplementation during lactation
appears
to blunt the lactationinduced increase in maternal blood lead and its
inhibitory effect on deltaALAD and possibly on maternal erythropoiesis.
15: J Am Soc Nephrol. 2002 Jun;13(6):160814.
Treatment with vitamin D and calcium reduces bone loss after renal transplantation:
a randomized study.
De Sevaux RG, Hoitsma AJ, Corstens FH, Wetzels JF.
A decrease in bone mineral density (BMD) is a major complication of renal
transplantation (RTx), predominantly occurring within the first 6 mo after
RTx.
The most important causative factor is the use of corticosteroids, but
persisting hyperparathyroidism and abnormalities in vitamin D metabolism
play a
role too. This study examines the effect of treatment with calcium and
active
vitamin D on the loss of BMD in the first 6 mo after RTx. A total of 111
renal
transplant recipients (65 men, 46 women; age, 47 +/ 13 yr) were randomized
to
either treatment with active vitamin D (0.25 microg/d) plus calcium (1000
mg/d)
(CaD group), or to no treatment (NoT group). Immunosuppressive therapy
consisted
of cyclosporine, prednisone, and mycophenolate mofetil. Laboratory parameters
and BMD (lumbar spine and hip) were measured at 0, 1 (laboratory only),
3, and 6
mo after RTx. Lumbar BMD was nearly normal at the time of RTx. In both
groups, a
significant decrease in lumbar BMD was observed during the first 3 mo
(CaD, 3.3
+/ 4.3%; P < 0.0001; NoT, 4.1 +/ 4.8%; P < 0.0001). Between the
third day and
sixth month, lumbar BMD slightly recovered in the CaD group, but it decreased
further in the NoT group (total loss 0 to 6 mo: CaD, 2.6 +/ 5.0% [P <
0.001];
NoT, 5.0 +/ 4.7% [P < 0.0001]). As a result, the amount of bone loss
at 6 mo
was significantly lower in the CaD group (P = 0.02). Loss of BMD at the
different femoral sites was also significantly reduced in the CaD group.
Apart
from a trend toward more frequent hypercalcemia in the CaD group, no clinical
or
biochemical differences existed between the groups. Treatment with a low
dose of
active vitamin D and calcium partially prevents bone loss at the lumbar
spine
and proximal femur during the first 6 mo after RTx.
16: Aliment Pharmacol Ther. 2002 May;16(5):91927.
Osteoporosis in inflammatory bowel disease: effect of calcium and vitamin
D with
or without fluoride.
Abitbol V, Mary JY, Roux C, Soule JC, Belaiche J, Dupas JL, Gendre JP,
Lerebours
E, Chaussade S; Groupe D'etudes Therapeutiques des Affections Inflammatoires
Digestives (GETAID).
BACKGROUND: Previous data have indicated low bone formation as a mechanism
of
osteoporosis in inflammatory bowel disease. Fluoride can stimulate bone
formation. AIM: To assess the effect of fluoride supplementation on lumbar
spine
bone mineral density in osteoporotic patients with inflammatory bowel
disease
treated in parallel with calcium and vitamin D. METHODS: In this prospective,
randomized, doubleblind, parallel and placebocontrolled study, 94 patients
with inflammatory bowel disease (lumbar spine T score below 2 standard
deviations, normal serum 25OH vitamin D), with a median age of 35 years,
were
included. Bone mineral density was measured by dualenergy Xray absorptiometry.
Patients were randomized to receive daily either sodium monofluorophosphate
(150
mg, n=45) or placebo (n=49) for 1 year, and all received calcium (1 g)
and
vitamin D (800 IU). The relative change in bone mineral density from 0
to 12
months was tested in each group (fluoride or placebo) and compared between
the
groups. RESULTS: Lumbar spine bone mineral density increased significantly
in
both groups after 1 year: 4.8 +/ 5.6% (n=29) and 3.2 +/ 3.8% (n=31) in
the
calciumvitamin Dfluoride and calciumvitamin Dplacebo groups, respectively
(P
< 0.001 for each group). There was no difference between the groups
(P=0.403).
Similar results were observed according to corticosteroid intake or disease
activity. CONCLUSIONS: Calcium and vitamin D seem to increase lumbar spine
density in osteoporotic patients with inflammatory bowel disease; fluoride
does
not provide further benefit.
17: J Bone Joint Surg Br. 2002 May;84(4):497503.
Positive effects of anabolic steroids, vitamin D and calcium on muscle
mass,
bone mineral density and clinical function after a hip fracture. A randomised
study of 63 women.
Hedstrom M, Sjoberg K, Brosjo E, Astrom K, Sjoberg H, Dalen N.
A total of 63 women who had an operation for a fracture of the hip was
randomly
allocated to one year of treatment either with anabolic steroids, vitamin
D and
calcium (anabolic group) or with calcium only (control group). The thigh
muscle
volume was measured by quantitative CT. The bone mineral density of the
hip,
femur and tibia was assessed by quantitative CT and dualenergy xray
absorptiometry and of the heel by quantitative ultrasound. Quantitative
CT
showed that the anabolic group did not lose muscle volume during the first
12
months whereas the control group did (p<0.01). There was less bone
loss in the
proximal tibia in the anabolic group than in the control group. The speed
of
gait and the Harris hip score were significantly better in the anabolic
group
after six and 12 months. Anabolic steroids, even in this moderate dose,
given in
combination with vitamin D and calcium had a beneficial effect on muscle
volume,
bone mineral density and clinical function in this group of elderly women.
18: Mutat Res. 2002 Apr 26;516(12):19.
The protective effect of calcium against genotoxicity of lead acetate
administration on bone marrow and spermatocyte cells of mice in vivo.
AboulEla EI.
The protective effect of calcium given orally by gavage with two doses
(40 and
80mg/kg body weight) was evaluated against clastogenecity induced by lead
acetate with two concentrations (200 and 400mg/kg diet) on bone marrow
and
spermatocyte cells of mice in vivo. The parameter screened was percentage
of
chromosomal aberrations with and without gaps and sperm abnormalities.
Statistical analyses indicated the protection efficacy of calcium with
the high
dose rather than the other in both types of mouse cells.The observation
from the
laboratory tests, dealing that lead acetate can be considered as an
environmental genotoxic material. We recommended that it must be administered
of
calcium (as calcium chloride) as a protective agent to reduce the genotoxic
effect of lead in the somatic and germ cells.
PMID 11943604
19: Am J Clin Nutr. 2002 Apr;75(4):7739.
Calcium intake influences the association of protein intake with rates
of bone
loss in elderly men and women.
DawsonHughes B, Harris SS.
BACKGROUND: There is currently no consensus on the effect of dietary
protein
intake on the skeleton, but there is some indication that low calcium
intakes
adversely influence the effect of dietary protein on fracture risk. OBJECTIVE:
The objective of the present study was to determine whether supplemental
calcium
citrate malate and vitamin D influence any associations between protein
intake
and change in bone mineral density (BMD). DESIGN: Associations between
protein
intake and change in BMD were examined in 342 healthy men and women (aged
> or =
65 y) who had completed a 3y, randomized, placebocontrolled trial of calcium
and vitamin D supplementation. Protein intake was assessed at the midpoint
of
the study with the use of a foodfrequency questionnaire and BMD was assessed
every 6 mo by dualenergy Xray absorptiometry. RESULTS: The mean (+/SD)
protein intake of all subjects was 79.1 +/ 25.6 g/d and the mean total
calcium
intakes of the supplemented and placebo groups were 1346 +/ 358 and 871
+/ 413
mg/d, respectively. Higher protein intake was significantly associated
with a
favorable 3y change in totalbody BMD in the supplemented group (in a model
containing terms for age, sex, weight, total energy intake, and dietary
calcium
intake) but not in the placebo group. The pattern of change in femoral
neck BMD
with increasing protein intake in the supplemented group was similar to
that for
the total body. CONCLUSION: Increasing protein intake may have a favorable
effect on change in BMD in elderly subjects supplemented with calcium
citrate
malate and vitamin D.
20: Cancer Causes Control. 2002 Apr;13(3):21320.
Calcium, vitamin D, and risk of adenoma recurrence (United States).
Martinez ME, Marshall JR, Sampliner R, Wilkinson J, Alberts DS.
OBJECTIVE: Few data exist regarding the association between calcium intake
and
adenoma recurrence, and no data exist for vitamin D. We investigated the
role of
dietary and supplemental sources of calcium and vitamin D in the etiology
of
adenoma recurrence. METHODS: Analyses were conducted among 1304 male and
female
participants in the Wheat Bran Fiber (WBF) trial of adenoma recurrence.
Multiple
logistic regression was used to calculate odds ratios (ORs) and 95% confidence
intervals (CIs). RESULTS: In the fully adjusted multivariate model, the
OR for
participants with dietary calcium intake above 1,068 versus those with
intake
below 698 mg/day was 0.56 (95% CI = 0.390.80; ptrend = 0.007). Calcium
supplementation at doses above 200 mg/day did not affect risk of recurrence.
Although a borderline inverse association between dietary vitamin D and
recurrence was observed after adjustment for age and gender, the association
weakened in the fully adjusted model (OR = 0.78 for individuals in the
upper
compared to the lower quartile; 95% CI = 0.541.13). No association was
shown
for supplemental sources of vitamin D. CONCLUSIONS: Results of this study
indicate that a higher intake of calcium decreases the risk of adenoma
recurrence by approximately 45%, whereas vitamin D has no significant
effect on
recurrence rates.
PMID 12020102
21: J Surg Res. 2002 Apr;103(2):24351.
Ischemic preconditioning improves mitochondrial tolerance to experimental
calcium overload.
Crestanello JA, Doliba NM, Babsky AM, Doliba NM, Niibori K, Whitman GJ,
Osbakken
MD.
BACKGROUND: Ca(2+) overload leads to mitochondrial uncoupling, decreased
ATP
synthesis, and myocardial dysfunction. Pharmacologically opening of
mitochondrial K(ATP) channels decreases mitochondrial Ca(2+) uptake, improving
mitochondrial function during Ca(2+) overload. Ischemic preconditioning
(IPC),
by activating mitochondrial K(ATP) channels, may attenuate mitochondrial
Ca(2+)
overload and improve mitochondrial function during reperfusion. The purpose
of
these experiments was to study the effect of IPC (1) on mitochondrial
function
and (2) on mitochondrial tolerance to experimental Ca(2+) overload. METHODS:
Rat
hearts (n = 6/group) were subjected to (a) 30 min of equilibration, 25
min of
ischemia, and 30 min of reperfusion (Control) or (b) two 5min episodes
of
ischemic preconditioning, 25 min of ischemia, and 30 min of reperfusion
(IPC).
Developed pressure (DP) was measured. Heart mitochondria were isolated
at
endEquilibration (endEQ) and at endReperfusion (endRP). Mitochondrial
respiratory function (state 2, oxygen consumption with substrate only;
state 3,
oxygen consumption stimulated by ADP; state 4, oxygen consumption after
cessation of ADP phosphorylation; respiratory control index (RCI, state
3/state
4); rate of oxidative phosphorylation (ADP/Deltat), and ADP:O ratio) was
measured with polarography using alphaketoglutarate as a substrate in
the
presence of different Ca(2+) concentrations (0 to 5 x 10(7) M) to simulate
Ca(2+) overload. RESULTS: IPC improved DP at endRP. IPC did not improve
preischemic mitochondrial respiratory function or preischemic mitochondrial
response to Ca(2+) loading. IPC improved state 3, ADP/Deltat, and RCI
during RP.
Low Ca(2+) levels (0.5 and 1 x 10(7) M) stimulated mitochondrial function
in
both groups predominantly in IPC. The Control group showed evidence of
mitochondrial uncoupling at lower Ca(2+) concentrations (1 x 10(7) M).
IPC
preserved state 3 at high Ca(2+) concentrations. CONCLUSIONS: The
cardioprotective effect of IPC results, in part, from preserving mitochondrial
function during reperfusion and increasing mitochondrial tolerance to
Ca(2+)
loading at endRP. Activation of mitochondrial K(ATP) channels by IPC and
their
improvement in Ca(2+) homeostasis during RP may be the mechanism underlying
this
protection.
PMID 11922741
22: Urology. 2002 Apr;59(4 Suppl 1):3440.
Complementary therapies for reducing the risk of osteoporosis in patients
receiving luteinizing hormonereleasing hormone treatment/orchiectomy for
prostate cancer: a review and assessment of the need for more research.
Moyad MA.
Osteoporosis in women has received a substantial amount of attention,
but its
impact in men is also significant and noteworthy. Those men who benefit
from
treatment for prostate cancer with androgen deprivation therapy (ADT)
may also
be at a higher risk for osteoporosis. Pharmacologic approaches to reduce
this
risk have received some attention. For example, agents such as bisphosphonates,
estrogen receptorbinding drugs (diethylstilbestrol, tamoxifen, and raloxifene),
calcitonin, and fluoride are some of the more promising interventions
that have
been previously outlined. In addition, statin drugs, or hepatic
3hydroxy3methylglutaryl coenzyme A reductase inhibitors, have recently
been
hypothesized to lower osteoporosis risk. However, complementary therapies,
which
may also have an impact on reducing osteoporosis risk, have not received
attention. Dietary and supplemental calcium and vitamin D have been shown,
in
some preliminary investigations, to maintain bone density in women and
men.
Numerous healthy and affordable dietary sources of this mineral and vitamin
exist, and large intakes can be realistically achieved through proper
education.
Similarly, the supplemental dosages required to impact risk have been
moderate,
appear to be safe, are of low cost, and thus may provide an additional
route for
reducing risk, especially if these interventions are initiated at the
start of
medical treatment. More studies in men receiving ADT are needed because
the
existing work has mostly focused on men without castrate levels of male
hormone.
Additionally, many studies with conventional and nonconventional agents
have
only focused on individuals with baseline osteoporosis, rather than normal
bone
mineral densities or osteopenia. Other promising complementary therapies,
such
as weightbearing exercise and abstaining from smoking, may also be of
benefit.
Newer estrogenictype supplements (eg, ipriflavone) appear interesting
and have
some preliminary data, but more research is desperately required to determine
their actual impact and potential for adverse effects (such as lymphocytopenia
from a recent trial). Simple, inexpensive, and potentially effective dietary
and
supplemental approaches to reduce the risk of osteoporosis in men exist,
and
they should be discussed with patients. Whether these approaches effectively
reduce the risk of osteoporosis in men receiving androgen ablation remains
to be
determined. The possibility is intriguing, and future research is needed.
In the
meantime, it is important to keep in mind that these complementary approaches
are, at the very least, an integral part of the conventional options used
today
to the reduce the risk of osteoporosis in men and women.
23: J Natl Cancer Inst. 2002 Mar 20;94(6):43746.
Calcium intake and risk of colon cancer in women and men.
Wu K, Willett WC, Fuchs CS, Colditz GA, Giovannucci EL.
BACKGROUND: Calcium has been hypothesized to reduce the risk of colon
cancer,
and in a recent randomized trial, calcium supplementation was associated
with
reduction in the risk of recurrent colorectal adenomas. We examined the
association between calcium intake and colon cancer risk in two prospective
cohorts, the Nurses' Health Study (NHS) and the Health Professionals Followup
Study (HPFS). METHODS: Our study population included 87 998 women in NHS
and 47 344 men in HPFS who, at baseline (1980 for NHS and 1986 for HPFS),
completed a
food frequency questionnaire and provided information on medical history
and
lifestyle factors. Dietary information was updated at least every 4 years.
During the followup period (1980 to May 31, 1996 for the NHS cohort; 1986
to
January 31, 1996 for the HPFS cohort), 626 and 399 colon cancer cases
were
identified in women and men, respectively. Pooled logistic regression
was used
to estimate relative risks (RRs), and all statistical tests were twosided.
RESULTS: In women and men considered together, we found an inverse association
between higher total calcium intake (>1250 mg/day versus < or =500
mg/day) and
distal colon cancer (women: multivariate RR = 0.73, 95% confidence interval
[CI]
= 0.41 to 1.27; men: RR = 0.58, 95% CI = 0.32 to 1.05; pooled RR = 0.65,
95% CI
= 0.43 to 0.98). No such association was found for proximal colon cancer
(women:
RR = 1.28, 95% CI = 0.75 to 2.16; men: RR = 0.92, 95% CI = 0.45 to 1.87;
pooled
RR = 1.14, 95% CI = 0.72 to 1.81). The incremental benefit of additional
calcium
intake beyond approximately 700 mg/day appeared to be minimal. CONCLUSIONS:
Higher calcium intake is associated with a reduced risk of distal colon
cancer.
The observed risk pattern was consistent with a threshold effect, suggesting
that calcium intake beyond moderate levels may not be associated with
a further
risk reduction. Future investigations on this association should concentrate
on
specific cancer subsites and on the doseresponse relationship.
24: Osteoporos Int. 2002 Mar;13(3):25764.
Combined calcium and vitamin D3 supplementation in elderly women: confirmation
of reversal of secondary hyperparathyroidism and hip fracture risk: the
Decalyos
II study.
Chapuy MC, Pamphile R, Paris E, Kempf C, Schlichting M, Arnaud S, Garnero
P,
Meunier PJ.
Vitamin D insufficiency and low calcium intake contribute to increase
parathyroid function and bone fragility in elderly people. Calcium and
vitamin D
supplements can reverse secondary hyperparathyroidism thus preventing
hip
fractures, as proved by Decalyos I. Decalyos II is a 2year, multicenter,
randomized, doublemasked, placebocontrolled confirmatory study. The
intentiontotreat population consisted of 583 ambulatory institutionalized
women (mean age 85.2 years, SD = 7.1) randomized to the calciumvitamin
D3 fixed
combination group (n = 199); the calcium plus vitamin D3 separate combination
group (n = 190) and the placebo group (n = 194). Fixed and separate combination
groups received the same daily amount of calcium (1200 mg) and vitamin
D3 (800
IU), which had similar pharmacodynamic effects. Both types of calciumvitamin
D3
regimens increased serum 25hydroxyvitamin D and decreased serum intact
parathyroid hormone to a similar extent, with levels returning within
the normal
range after 6 months. In a subgroup of 114 patients, femoral neck bone
mineral
density (BMD) decreased in the placebo group (mean = 2.36% per year, SD
=
4.92), while remaining unchanged in women treated with calciumvitamin
D3 (mean
= 0.29% per year, SD = 8.63). The difference between the two groups was
2.65%
(95% CI = 0.44, 5.75%) with a trend in favor of the active treatment group.
No
significant difference between groups was found for changes in distal
radius BMD
and quantitative ultrasonic parameters at the os calcis. The relative
risk (RR)
of HF in the placebo group compared with the active treatment group was
1.69
(95% CI = 0.96, 3.0), which is similar to that found in Decalyos I (RR
= 1.7;
95% CI = 1.0, 2.8). Thus, these data are in agreement with those of Decalyos
I
and indicate that calcium and vitamin D3 in combination reverse senile
secondary
hyperparathyroidism and reduce both hip bone loss and the risk of hip
fracture
in elderly institutionalized women.
25: Osteoporos Int. 2002 Mar;13(3):2117.
Association of physical activity and calcium intake with the maintenance
of bone
mass in premenopausal women.
UusiRasi K, Sievanen H, Pasanen M, Oja P, Vuori I.
Altogether 92 initially 25 to 30yearold women of 132 original subjects
participated in this 4year followup study, which evaluated the influence
of
physical activity and calcium intake on the bone mineral content (BMC)
of
premenopausal women. The subjects were originally selected for a crosssectional
study according to their level of physical activity (high PA+ and low
PA) and
calcium intake (high Ca+ and low Ca), and the original groups were maintained
in this followup study. The mean loss of BMC (95% CI) in the pooled data
was
1.5% (0.7% to 2.4%) at the femoral neck, 0.6% (0.8% to 1.9%) at the trochanter
and 6.0% (4.5% to 7.4%) at the distal radius during the 4year followup.
According to repeated measures analyses of covariance neither physical
activity
nor physical fitness at baseline was associated with the rate of bone
loss from
the proximal femur. High calcium intake and the maintenance of body weight
were
both associated with a lower rate of bone loss from the proximal femur
and
distal radius. In addition, a long duration of breast feeding was associated
with a higher rate of bone loss from the distal radius.
PMID 11991440
26: Acta Neurol Scand. 2002 Feb;105(2):12831.
Reversible peripheral neuropathy in idiopathic hypoparathyroidism.
Goswami R, Bhatia M, Goyal R, Kochupillai N.
We describe a 40yearold male with idiopathic hypoparathyroidism presenting
with tetany, proximal weakness, signs of hypocalcaemia including Chvostek
and
Trousseau's and diminished tendon reflexes in the upper and lower limbs.
Electrophysiological studies revealed a sensorymotor neuropathy, predominantly
axonal as evidenced by decreased CMAP amplitudes, with normal distal
latenciesvelocites, except for median nerve where a prolonged distal latency
was observed. Serial nerve conduction studies were performed at repeated
intervals for 2 years, while he received treatment for hypoparathyroidism
(calcium and vitamin D supplementation). A progressive improvement in
neuropathy
both clinical and on electrophysiological studies was observed. Occurrence
of
peripheral neuropathy in hypocalcaemic states such as hypoparathyroidism
and its
reversibility after normalization of calcium homeostasis lend proof to
the role
of critical Ca2+ ion concentration in the normal functioning of the peripheral
axons.
PMID 11903124
27: Eur J Endocrinol. 2002 Feb;146(2):21522.
Wellbeing, mood and calcium homeostasis in patients with hypoparathyroidism
receiving standard treatment with calcium and vitamin D.
Arlt W, Fremerey C, Callies F, Reincke M, Schneider P, Timmermann W, Allolio
B.
OBJECTIVE: Standard treatment in hypoparathyroidism consists of calcium
and
vitamin D (or vitamin D analogs) but does not employ replacement of the
actual
missing hormone. Only few studies have evaluated the efficacy of calcium/vitamin
D treatment in hypoparathyroidism; the impact of chronic hypoparathyroid
disease
on wellbeing has not been investigated previously. DESIGN: Crosssectional,
controlled study in 25 unselected women with postsurgical hypoparathyroidism
since 6.4plus minus8.0 years (s.d.) on stable treatment with calcium and
vitamin
D (or analogs) and in 25 controls with a history of thyroid surgery but
intact
parathyroid function, who were matched for sex, age and time since surgery.
METHODS: Assessment of wellbeing and mood using validated questionnaires
(the
revised version Symptom Checklist 90 (SCL90R); the Giessen Complaint List
(GBB24); and the von Zerssen Symptom List (BL Zerssen)), serum and urinary
calcium/phosphorus homeostasis, and in the hypoparathyroid patients also
screening for secondary disease by kidney ultrasound, ophthalmological
split
lamp examination, and measurement of bone mineral density. RESULTS: Serum
calcium was in the accepted therapeutic range in the majority of hypoparathyroid
patients. However, calcium/phosphorus homeostasis as a whole was clearly
nonphysiological. Nephrolithiasis was detected in 2 and cataracts in 11
of 25
hypoparathyroid patients. As compared with controls, hypoparathyroid patients
had significantly higher global complaint scores in GBB24 (P=0.036), BL
Zerssen (P=0.002) and SCL90R (P=0.020) with predominant increases in the
subscale scores for anxiety, phobic anxiety and their physical equivalents.
CONCLUSIONS: Current standard treatment in hypoparathyroidism is not only
associated with an altered calcium/phosphorus homeostasis but also fails
to
restore wellbeing in these patients. Future studies need to address the
impact
of more physiological treatment options like parathyroid hormone(134)
or
parathyroid transplantation on wellbeing and mood in these patients.
PMID 11834431
28: Int J Technol Assess Health Care. 2002 Fall;18(4):791807.
The health economics of calcium and vitamin D3 for the prevention of
osteoporotic hip fractures in Sweden.
Willis MS.
OBJECTIVE: The objective of this study was to examine the economics of
administering calcium and vitamin D3 to postmenopausal women in Sweden.
We
focus primarily on the costeffectiveness of treating older women for whom
clear
evidence of efficacy is available. We supplement this information, however,
with
estimates of the costeffectiveness of treating certain highrisk groups
of
younger women, while acknowledging the greater uncertainty involved. METHODS:
We
developed a Markov model for analyzing the occurrence and timing of hip
fractures, based almost entirely on peerreviewed data from Sweden. In
a 3year
randomized clinical trial, the combination of calcium and vitamin D3 was
shown
to reduce the risk of hip fractures by 27%. Costs for treating hip fractures
were based on 1,080 women who were hospitalized in Stockholm. RESULTS:
Treatment
of 70yearold women was cost saving at efficacy as low as twothirds that
seen
in the clinical trials, and upwards. Even at modest rates of efficacy,
treatment
of the highrisk 50 and 60yearold cohorts was generally costeffective and
in
some cases even cost saving. Particularly costeffective was treatment
of women
with identified osteoporosis or a maternal family history of hip fracture.
CONCLUSION: Simulation results suggest a role for lifetime treatment of
older
women with calcium and vitamin D3 in Sweden. While there is more uncertainty
underlying the treatment of younger women, our simulation results suggest
that
treatment may also be cost saving or at least costeffective for many cohorts
of
highrisk 50 and particularly 60yearold women, in particular those with
osteoporosis or a maternal family history of hip fracture.
PMID 12602080
29: Med Clin (Barc). 2001 Nov 17;117(16):6114.
[Prevalence of hypovitaminosis D in elderly institutionalized residents:
influence of a substitutive treatment]
Larrosa M, Gratacos J, Vaqueiro M, Prat M, Campos F, Roque M.
BACKGROUND: Osteoporosis in the elderly is a common and severe disease,
vitamin
D deficiency being an important causative factor. Hypovitaminosis D is
frequent
in old people, particularly those living in nursing homes. SUBJECTS AND
METHOD:
We performed a crosssectional study of 100 randomly recruited elderly
institutionalized subjects. The prevalence of hypovitaminosis D and its
possible
repercussion on the phosphocalcium metabolism were assessed. The degree
of sun
exposure and the existence of comorbidity were also recorded. Individuals
with
hypovitaminosis D were included in a longitudinal study (6 months' duration)
aimed at assess the efficacy of treatment with calcium and two different
therapeutic regimens with calcidiol (16,000 IU/week or 16,000 IU every
3 weeks).
RESULTS: 87% of individuals had hypovitaminosis D; 21.8% of them had secondary
hyperparathyroidism. The study population had a low degree of sun exposure
and a
high level of comorbidity. The two doses of calcidiol led to a normalization
of
25OHD3 levels, increased calciuria and compensated secondary
hyperparathyroidism, yet higher 25OHD3 levels were achieved with the weekly
therapeutic scheme. CONCLUSIONS: Hypovitaminosis D prevalence appears
to be very
high In the elderly institutionalized population. Calcium and calcidiol
supplementation normalized 25OHD3, improved calcium absorption and compensated
secondary hyperparathyroidism. Calcium and vitamin D supplementation should
be
employed routinely in the elderly institutionalized population.
30: Ann Oncol. 2001 Nov;12(11):158993.
Micronutrients and ovarian cancer: a casecontrol study in Italy.
Bidoli E, La Vecchia C, Talamini R, Negri E, Parpinel M, Conti E, Montella
M,
Carbone MA, Franceschi S.
BACKGROUND: The role of selected micronutrients, vitamins and minerals
in the
aetiology of epithelial ovarian cancer was investigated using data from
a
casecontrol study conducted between 1992 and 1999 in five Italian areas.
PATIENTS AND METHODS: Cases were 1,031 patients with histologically confirmed
incident epithelial ovarian cancer. Controls were 2,411 subjects admitted
for
acute, nonneoplastic diseases to major hospitals in the same catchment
areas.
Dietary habits were elicited using a validated food frequency questionnaire
including 78 food groups and recipes. Odds ratios (OR) and 95% confidence
intervals (95% CI) were computed by quintiles of intake of nutrients.
RESULTS:
Inverse associations emerged for vitamin E (OR = 0.6; 95% CI: 0.50.8),
betacarotene (OR = 0.8; 95% CI: 0.61.0), lutein/zeaxanthin (OR = 0.6;
95% CI:
0.50.8 for the highest vs. the lowest quintile of intake), and calcium
intake
(OR = 0.7; 95% CI: 0.61.0). When the combined effect of calcium and vitamin
E
was considered, the OR reached 0.4 (95% CI: 0.30.7) for subjects in the
highest
compared to those in the lowest intake tertile of both micronutrients.
Results
were consistent across strata of menopausal status, parity and family
history of
ovarian or breast cancer. CONCLUSIONS: The intake of selected micronutrients,
which were positively correlated to a diet rich in vegetables and fruits,
was
inversely associated with ovarian cancer.
PMID 11822759
31: Calcif Tissue Int. 2001 Jun;68(6):3527. Epub 2001 May 21.
Acute effects in healthy women of oral calcium on the calciumparathyroid
axis
and bone resorption as assessed by serum betaCrossLaps.
Zikan V, Haas T, Stepan JJ.
The purpose of this investigation was to test the hypothesis that the
decrease
in bone resorption after the calcium (Ca) load can be assessed by serum
type 1
collagen crosslinked Ctelopeptide (Elecsys betaCrossLaps, Roche) (SCTX).
Six
young healthy women (2327 years of age) and six healthy late postmenopausal
women (6369 years of age) with normal bone mineral density (BMD) received,
after overnight fasting, 1 g of elemental Ca (in the form of calcium carbonate)
dissolved in 250 ml of water or only plain water (fasting period). In
addition,
the late postmenopausal women were tested with an additional dose of 0.2
g of
elemental Ca in 250 ml of water. Serum ionized Ca (SiCa), SCTX, plasma
immunoreactive intact parathormone (PPTH) were measured before and during
the 5
hours after the oral intake of Ca. Urine was collected at regular intervals,
and
urinary Ca and creatinine were analyzed. In both the young and late
postmenopausal subjects, the load with Ca resulted in a significant increase
in
SiCa and urine Ca/creatinine ratio as well and a significant decrease
of PPTH
and SCTX compared with the fasting period. The comparison of the effects
of 1 g
Ca load between young and late postmenopausal women did not show any statistical
significance in any measured parameters. In the late postmenopausal women,
a
significantly greater increase in SiCa concentrations and a significantly
greater decrease in PPTH after 1 g were observed compared with those after
a
0.2 g dose of Ca. During the first 3 hours, the load of both 1 g and 0.2
g of Ca
induced a similar decrease in SCTX. After 5 hours, however, SCTX were
significantly more suppressed after a 1 g dose than after a 0.2 g dose
of Ca. In
conclusion, a single oral morning dose of 1 g Ca suppresses bone resorption,
as
assessed by SCTX, to a similar degree in both young and late postmenopausal
women with normal Ca absorption. In healthy late postmenopausal women
the load
of 0.2 g of Ca carbonate significantly suppresses bone resorption.
PMID 11685423
32: J Clin Endocrinol Metab. 2001 Apr;86(4):16337.
Effects of a shortterm vitamin D(3) and calcium supplementation on blood
pressure and parathyroid hormone levels in elderly women.
Pfeifer M, Begerow B, Minne HW, Nachtigall D, Hansen C.
Calcium supplementation is effective in reducing blood pressure in various
states of hypertension, including pregnancyinduced hypertension and
preeclampsia. In addition, calcitropic hormones are associated with blood
pressure. The hypothesis is that shortterm therapy with calcium and vitamin
D(3) may improve blood pressure as well as secondary hyperparathyroidism
more
effectively than calcium monotherapy. The effects of 8 weeks of supplementation
with vitamin D(3) (cholecalciferol) and calcium on blood pressure and
biochemical measures of bone metabolism were studied. The sample consisted
of
148 women (mean +/ SD age, 74 +/ 1 yr) with a 25hydroxycholecalciferol
(25OHD(3)) level below 50 nmol/L. They received either 1200 mg calcium
plus 800
IU vitamin D(3) or 1200 mg calcium/day. We measured intact PTH, 25OHD(3),
1,25dihydroxyvitamin D(3), blood pressure, and heart rate before and after
treatment. Compared with calcium, supplementation with vitamin D(3) and
calcium
resulted in an increase in serum 25OHD(3) of 72% (P < 0.01), a decrease
in serum
PTH of 17% (P = 0.04), a decrease in systolic blood pressure (SBP) of
9.3% (P =
0.02), and a decrease in heart rate of 5.4% (P = 0.02). Sixty subjects
(81%) in
the vitamin D(3) and calcium group compared with 35 (47%) subjects in
the
calcium group showed a decrease in SBP of 5 mm Hg or more (P = 0.04).
No
statistically significant difference was observed in the diastolic blood
pressures of the calciumtreated and calcium plus vitamin D(3)treated groups
(P = 0.10). Pearson coefficients of correlation between the change in
PTH and
the change in SBP were 0.49 (P < 0.01) for the vitamin D(3) plus calcium
group
and 0.23 (P < 0.01) for the calcium group. A shortterm supplementation
with
vitamin D(3) and calcium is more effective in reducing SBP than calcium
alone.
Inadequate vitamin D(3) and calcium intake could play a contributory role
in the
pathogenesis and progression of hypertension and cardiovascular disease
in
elderly women.
33: Public Health Nutr. 2001 Apr;4(2B):54759.
Calcium and vitamin D nutrition and bone disease of the elderly.
Gennari C.
Osteoporosis, a systemic skeletal disease characterized by a low bone
mass, is a
major public health problem in EC member states because of the high incidence
of
fragility fractures, especially hip and vertebral fracture. In EC member
states
the high incidence of osteoporotic fractures leads to considerable mortality,
morbidity, reduced mobility and decreased quality of life. In 1995 the
number of
hip fractures in 15 countries of EC has been 382,000 and the estimated
total
care cost of about 9 billion of ECUs. Given the magnitude of the problem
public
health measures are important for preventive intervention. Skeletal bone
mass is
determined by a combination of endogenous (genetic, hormonal) and exogenous
(nutritional, physical activity) factors. Nutrition plays an important
role in
bone health. The two nutrients essential for bone health are calcium and
vitamin
D. Reduced supplies of calcium are associated with a reduced bone mass
and
osteoporosis, whereas a chronic and severe vitamin D deficiency leads
to
osteomalacia, a metabolic bone disease characterized by a decreased
mineralization of bone. Vitamin D insufficiency, the preclinical phase
of
vitamin D deficiency, is most commonly found in the elderly. The major
causes of
vitamin D deficiency and insufficiency are decreased renal hydroxylation
of
vitamin D, poor nutrition, scarce exposition to sunlight and a decline
in the
synthesis of vitamin D in the skin. The daily average calcium intake in
Europe
has been evaluated in the SENECA study concerning the diet of elderly
people
from 19 towns of 10 European countries. In about one third of subjects
the
dietary calcium intake results were very low, between 300 and 600 mg/day
in
women, and 350 and 700 mg/day in men. Calcium supplements reduce the rate
of
bone loss in osteoporotic patients. Some recent studies have reported
a
significant positive effect of calcium treatment not only on bone mass
but also
on fracture incidence. The SENECA study, has also shown that vitamin D
insufficiency is frequent in elderly populations in Europe. There are
a number
of studies on the effects of vitamin D supplementation on bone loss in
the
elderly, showing that supplementations with daily doses of 400800 IU of
vitamin
D, given alone or in combination with calcium, are able to reverse vitamin
D
insufficiency, to prevent bone loss and to improve bone density in the
elderly.
In recent years, there has been much uncertainty about the intake of calcium
for
various ages and physiological states. In 1998, the expert committee of
the
European Community in the Report on OsteoporosisAction on prevention,
has given
the recommended daily dietary allowances (RDA) for calcium at all stage
of life.
For the elderly population, above age 65 the RDA is 700800 mg/day. The
main
source of calcium in the diet are dairy products (milk, yoghurts and cheese)
fish (sardines with bones), few vegetables and fruits. The optimal way
to
achieve adequate calcium intake is through the diet. However, when dietary
sources are scarce or not well tolerated, calcium supplementation may
be used.
Calcium is generally well tolerated and reports of significant sideeffects
are
rare. Adequate sunlight exposure may prevent and cure vitamin D insufficiency.
However, the sunlight exposure or the ultraviolet irradiation are limited
by
concern about skin cancer and skin disease. The most rational approach
to
reducing vitamin D insufficiency is supplementation. In Europe, the RDA
is
400800 IU (1020 microg) daily for people aged 65 years or over. This dose
is
safe and free of side effects. In conclusion, in Europe a low calcium
intake and
a suboptimal vitamin D status are very common in the elderly. Evidence
supports
routine supplementation for these people at risk of osteoporosis, by providing
a
daily intake of 700800 mg of calcium and 400800 IU of vitamin D. This
is an
effective, safe and cheap means of preventing osteoporotic fractures.
Publication Types:
Review
Review, Tutorial
34: Rheum Dis Clin North Am. 2001 Feb;27(1):10130.
Calcium and vitamin D in osteoporosis.
Morgan SL.
Calcium and vitamin D are useful adjunctive therapies in the prevention
and
treatment of osteoporosis. Peak BMD is optimally achieved with sustained
optimal
calcium and vitamin D intakes. Calcium and vitamin D intakes continue
to be
important after the third decade and into senescence. Although calcium
and
vitamin D are not therapies to be used alone to prevent early postmenopausal
bone loss, they assume more prominent roles in late menopause and in the
elderly
to preserve bone health with advancing age. Calcium and vitamin D
supplementation is an important adjunctive therapy to use together with
antiresorptive therapies.
35: Calcif Tissue Int. 2000 Dec;67(6):4402.
Inhibition of bone resorption by divideddose calcium supplementation in
early
postmenopausal women.
Scopacasa F, Need AG, Horowitz M, Wishart JM, Morris HA, Nordin BE.
We have previously shown that a calcium (Ca) supplement of 1000 mg given
in the
evening reduces the overnight and early morning, but not the daytime,
excretion
of bone resorption markers in postmenopausal women within five years of
the
menopause. In the present study, we have looked at the effect of splitting
the
Ca into two doses of 500 mg each given in the morning and evening. We
studied 19
healthy women (median age 53 years) who were all within 5 years of the
menopause. On the 2 study days, urine was collected from 9 a.m. to 9 p.m.
(day
collection), and from 9 p.m. to 9 a.m. (night collection); a further fasting
(spot) urine sample was obtained at 9 a.m. at the end of the night collection.
The first day was a control day; on the second day the subjects ingested
500 mg
Ca as the carbonate at 9 a.m. and 9 p.m. We measured pyridinoline crosslinks
excretion in all the samples, as well as hydroxyproline in the fasting
urine.
The Ca supplements lowered urinary excretion of the markers during the
day (P <
0.01), had only a marginal effect during the night, but reduced excretion
significantly in the fasting urine (P < 0.001). In the whole 24hour
period, the
falls in resorption markers were small but comparable to those seen after
the
ingestion of 1 g of Ca in the evening. We conclude that the acute administration
of 0.5 g Ca in the morning and evening reduced the markers of bone resorption
in
early postmenopausal women during the day but not during the following
night,
whereas the single 1 g supplement had the reverse effect. Over the 24hour
period, there was nothing to choose between the two regimes. Women at
this stage
in their life cycle probably require a larger Ca supplement if they are
not
taking estrogen.
36: Med Wieku Rozwoj. 2000 OctDec;4(4):42330.
[Current views on requirements for vitamin D, calcium and phosphorus,
particularly in formula fed infants]
Ksiazyk J.
Calcium (Ca) and phosphorus (P) absorption depends on vitamin D. Vitamin
deficiency in children results in rickets and osteoporosis in adults.
Prematurely born infants are at risk of osteopenia and rickets. Skin synthesis
of vitamin D can obtain the level of 10 000 IU (250 ug) when the whole
body is
exposed to the sun. Recent opinion on vitamin D requirement establishes
the
level of more than 80 nmol/L of 25(OH)D. There are no recommendations
for
children but it seems that due to the risk of skin cancer, exposure to
the sun
in children will be limited and as a result higher dose of vitamin D will
be
needed. Calcium and phosphorus are the most common minerals of the human
body.
Calcium concentration in human milk is not related to the intake. Calcium
intake
of calcium in premature infants is 70140 mg/100 kcal. Phosphorus content
in
breast milk, even as low as 15 mg%, can maintain the optimal Ca/P ratio
of 2/1.
Prolonged breast feeding without additional Ca and P, may result in reduced
bone
mineralisation. Higher content of calcium in infant formula in comparison
to
human milk is due to the fact that Ca absorption from breast milk is 60%
in
comparison to 40% absorption from the formula.
37: Med Clin (Barc). 2000 Jun 10;115(2):4651.
[Treatment of osteoporosis with calcium and vitamin D. Systematic review]
Vallecillo G, Diez A, Carbonell J, Gonzalez Macias J.
BACKGROUND: Systematic review of the efficacy of calcium and vitamin
D for the
treatment of osteoporosis. MATERIAL AND METHOD: Review of the database
MEDLINE
between 1996 and may 1998, by the key words: osteoporosis, calcium, vitamin
D
(and related terms) and randomized clinical trial. Review of the electronic
versions of Best Evidence, The Cochrane Library, congress abstracts and
references from two main textbooks. Ascending review of the literature.
All the
reviews were performed independently by two of the authors. Design parameters
and main results of the primary publications of the identified trials
were
tabulated. Two independent observers carried out methodological scoring
of the
studies. Results were tabulated and a judgement made for the results.
RESULTS:
Eleven studies on calcium, 8 of vitamin D and 12 about calcitriol and
other
hormone derivatives were included. Studies with calcium were mainly performed
on
nonclinical populations and in three antifracture efficacy was analyzed.
Results were positive in population with low baseline intake and substantial
supplementation. Trials on vitamin D were done in nonclinical and on
institutionalized populations. Trials with calcitriol were developed mainly
in
osteoporotic fracture populations and reached poorer methodological validity
scores. Heterogeneity of the studies precluded a metaanalysis of the different
treatments. Studies on calcium showed clinical efficacy in a more consistent
way. Interobserver score was good (kappa = 0.81) and there were no significant
correlations between sample size and effect in the different studies.
CONCLUSIONS: Calcium treatment is efficacious in populations with low
intake
receiving substantial supplementation. Vitamin D is efficacious associated
with
calcium mainly in deficient populations. Efficacy of calcitriol and other
derivatives is more controversial.
38: Dev Med Child Neurol. 2000 Jun;42(6):4035.
Effect of vitamin D and calcium on bone mineral density in children with
CP and
epilepsy in fulltime care.
JekovecVrhovsek M, Kocijancic A, Prezelj J.
Atraumatic fractures are often seen in children and adolescents with
cerebral
palsy (CP) and epilepsy in fulltime care. Increased bone fragility was
postulated to be due to osteopenia resulting from a combination of factors
including immobilization and antiepileptic treatment. The aim of this
study was
to determine the effect of vitamin D and calcium substitution on bone
mineral
density (BMD) in a group of children with CP in fulltime care. Twenty
children
with the most severe form of CP (spastic quadriplegia) who had been treated
with
antiepileptic drugs for a relatively long period of time were included
in the
study. Physical examination and laboratory analyses excluded other possible
causes of osteopenia. BMD was measured by dual Xray absorptiometry. Thirteen
patients were treated for 9 months with 1,25dihydroxycholecalciferol vitamin
D
(0.25 mcg daily) and with calcium (500 mg daily). Seven control children
were
used for observation only. BMD greatly increased in the treated group,
while
children with CP in fulltime care who did not receive vitamin D and calcium
substitution continued to lose their bone mass. It can be concluded that
the
addition of vitamin D and calcium increases BMD in children with the most
severe
form of CP, who are receiving antiepileptic drugs.
39: Nephrol Dial Transplant. 2000 Jun;15(6):87782.
Changes in bone turnover after parathyroidectomy in dialysis patients:
role of
calcitriol administration.
Mazzaferro S, Chicca S, Pasquali M, Zaraca F, Ballanti P, Taggi F, Coen
G,
Cinotti GA, Carboni M.
BACKGROUND: Available data on changes in serum levels of bone markers
after
parathyroidectomy (PTx) in dialysis patients are not uniform. Changes
are
thought to be due to either a reduction in PTH activity per se or to a
direct
effect of vitamin D therapy on bone cells. We aimed to verify whether
treatment
with vitamin D modifies serum levels of markers of bone synthesis (alkaline
phosphatase (AP), osteocalcin (BGP), procollagen type I Cterminal peptide
(PICP)) and resorption (collagen type I Cterminal peptide (ICTP)) within
a
period of 15 days in haemodialysis patients with severe secondary
hyperparathyroidism following PTx. METHODS: We randomized two groups (A,
treatment and B, placebo, 10 patients each) with comparable basal PTH
values and
measured bone markers 3, 7 and 15 days after surgery. All patients were
treated
with calcium supplements (i.v. and p.o.), and group A also received calcitriol
(2.4+/1.0 microg/day, p.o.). RESULTS: In both groups, PTx induced significant
changes in all the markers evaluated, except for BGP in group B. Compared
to
basal values, ICTP decreased from 481+/152 ng/ml in group A and 277+/126
ng/ml
in group B to 267+/94 and 185+/71 ng/ml (M+/SD) respectively, and PICP
increased from 307+/139 ng/ml in group A and 309+/200 ng/ml in group B
to
1129+/725 and 1231+/1267 ng/ml (M+/SD) respectively, within 3 days of
surgery. AP values increased after 15 days from 1115+/734 mU/ml in group
A and
1419+/1225 mU/ml in group B to 1917+/1225 and 1867+/1295 mU/ml (M+/SD)
respectively. On the contrary, mean values of BGP were never different
from
basal levels after PTx in either group. In the two groups, the pattern
of
changes of all the bone markers after PTx was almost identical. Group
A patients
predictably required lower doses of oral calcium supplements to correct
hypocalcaemia (16. 9+/5.7 vs 22.1+/5.0 g/10 days; M+/SD, P<0.04).
CONCLUSIONS: The opposite behaviour of serum PICP and ICTP after PTx,
in both
the treated and untreated groups suggests that quantitative uncoupling
between
bone synthesis and resorption is responsible for hypocalcaemia. This phenomenon,
as reflected by the evaluated bone markers, is unaffected by calcitriol.
Based
on our data we conclude that immediately after parathyroid surgery, vitamin
D
therapy does not influence bone cell activity, but improves hypocalcaemia
mainly
through its known effect on intestinal calcium absorption.
40: Psychopharmacology (Berl). 2000 Jun;150(2):2205.
The effects of an oral multivitamin combination with calcium, magnesium,
and
zinc on psychological wellbeing in healthy young male volunteers: a
doubleblind placebocontrolled trial.
Carroll D, Ring C, Suter M, Willemsen G.
RATIONALE: Vitamin and mineral supplements may be associated with improved
psychological status. OBJECTIVE: The present study tested the effects
of a
multivitamin and mineral supplement (Berocca) on psychological wellbeing.
METHODS: In a doubleblind randomisedcontrol trial, 80 healthy male volunteers
were assigned to either Berocca or placebo. Questionnaires measuring
psychological state were completed and a blood sample taken to determine
plasma
zinc concentration on day 1 (pretreatment) and again on day 28
(posttreatment), following 28 days of treatments, which were administered
at a
dosage of one tablet daily. At the end of the study, the acceptability
of the
treatment and participants' awareness of treatment condition were assessed,
as
was habitual dietary behaviour. RESULTS: Relative to placebo, treatment
with
Berocca was associated with consistent and statistically significant reductions
in anxiety and perceived stress. Participants in the Berocca group also
tended
to rate themselves as less tired and better able to concentrate following
treatment. In addition, participants registered more somatic symptoms
following
placebo than following Berocca. These effects cannot be attributed to
differences in the acceptability of the two treatments or to participants
guessing what treatment they received. CONCLUSION: These findings demonstrate
that Berocca significantly reduces anxiety and perceived stress.
41: Ned Tijdschr Geneeskd. 2000 May 6;144(19):9003.
[Hypocalcemia as a cause of reversible heart failure]
Bolk J, Ruiter JH, van Geelen JA.
A 72yearold woman with therapy resistant congestive heart failure presented
with severe hypocalcaemia due to hypoparathyroidism after strumectomy
more than
25 years before. After suppletion of calcium her complaints resolved and
there
was considerable improvement in left ventricular function. Our case report
suggests that hypocalcaemia induced cardiomyopathy should be considered
in the
differential diagnosis of therapy resistant heart failure and that myocardial
impairment is reversible after administration of calcium.
42: Proc Nutr Soc. 2000 May;59(2):295301.
Changing eating and physical activity patterns of US children.
Johnson RK.
The number of US children who are overweight has more than doubled over
the last
decade. This change has broadened the focus of dietary guidance for children
to
address nutrient overconsumption and physical activity patterns. Total
fat
consumption expressed as a percentage of energy intake has decreased among
US
children. However, this decrease is largely the result of increased total
energy
intake in the form of carbohydrates and not necessarily due to decreased
fat
consumption. The majority of children aged 517 years are not meeting
recommendations for Ca intakes. Much of this deficit is attributed to
changing
beverage consumption patterns, characterized by declining milk intakes
and
substantial increases in softdrink consumption. On average, US children
are not
eating the recommended amounts of fruits and vegetables. US adolescents
become
less active as they get older, and onequarter of all US children watch
> or = 4
h television each day, which is positively associated with increased BMI
and
skinfold thickness. There is an urgent need in the USA for effective prevention
strategies aimed at helping children grow up with healthful eating and
physical
activity habits to achieve optimal health.
43: Jpn J Physiol. 2000 Apr;50(2):20713.
Involvement of Ca(2+) in antiarrhythmic effect of ischemic preconditioning
in
isolated rat heart.
Hong K, Kusano KF, Morita H, Fujimoto Y, Nakamura K, Yamanari H, Ohe T.
We investigated the relationship between the effects of ischemic preconditioning
(IPC) and Ca(2+) preconditioning (CPC) on reperfusioninduced arrhythmias.
In
the control group (noPC), Langendorffperfused rat hearts were subjected
to
5min zeroflow global ischemia (I) followed by 15min reperfusion (I/R).
In
ischemic preconditioning groups (IPC), the hearts were subjected to three
cycles
of 3min global ischemia and 5min reperfusion. In the CPC group, the hearts
were exposed to three cycles of 3min perfusion of higher Ca(2+) (2.3 mmol/l
Ca(2+)) followed by 5min perfusion of normal 1.3 mmol/l Ca(2+), and the
hearts
were then subjected to I/R. Verapamil was administered in several hearts
of the
IPC group (VR+IPC). Ventricular arrhythmias upon reperfusion were less
frequently seen in the IPC and CPC groups than in the noPC and VR+IPC
groups.
IPC and CPC could attenuate conduction delay and enhance shortening of
the
monophasic action potential duration during ischemia. The ventricular
fibrillation threshold measured at 1min reperfusion was significantly
higher in
the IPC and CPC groups than in the noPC and VR+IPC groups. Verapamil completely
abolished the salutary effects of IPC. These results demonstrate that
Ca(2+)
plays an important role in the antiarrhythmic effect of IPC during reperfusion.
PMID 10880877
44: Ann Intern Med. 2000 Mar 7;132(5):34553.
Low fractional calcium absorption increases the risk for hip fracture
in women
with low calcium intake. Study of Osteoporotic Fractures Research Group.
Ensrud KE, Duong T, Cauley JA, Heaney RP, Wolf RL, Harris E, Cummings
SR.
BACKGROUND: Decreased ability to absorb calcium with age limits adaptation
to
low calcium intake and is thought to lead to secondary hyperparathyroidism
and
increased risk for hip and other fractures. However, the associations
between
fractional calcium absorption, dietary calcium intake, and risk for fracture
have never been studied. OBJECTIVE: To determine whether low fractional
calcium
absorption in women with low calcium intake increases the risk for subsequent
hip and other nonspine fractures. DESIGN: Prospective cohort study. SETTING:
Four clinical centers in Baltimore County, Maryland; Portland, Oregon;
Minneapolis, Minnesota; and the Monongahela Valley, Pennsylvania. PARTICIPANTS:
5452 nonblack women 69 years of age or older participating in the fourth
examination of the Study of Osteoporotic Fractures. MEASUREMENTS: Fractional
calcium absorption was measured by using a 3hour single isotope (45Ca)
technique. Incident fractures were identified prospectively and were confirmed
by radiographic report. RESULTS: During an average of 4.8 years, 729 women
(13%)
experienced at least one nonspine fracture; 153 of these women had hip
fractures. After adjustment for age, women with lower fractional calcium
absorption were at increased risk for hip fracture (relative risk per
1SD
[7.7%] decrease in fractional calcium absorption, 1.24 [95% CI, 1.05 to
1.48]).
Women with low fractional calcium absorption and low calcium intake were
at
greatest risk for subsequent hip fracture; among women whose dietary calcium
intake was less than 400 mg/d, those who had fractional calcium absorption
at or
below the median value of 32.3% had a 2.5fold (CI, 1.29fold to 4.69fold)
increase in risk for hip fracture compared with those who had greater
absorption
efficiency. Fractional calcium absorption was not related to risk for
other
nonspine fractures (relative risk per 1SD [7.7%] decrease in fractional
calcium
absorption, 1.05 [CI, 0.96 to 1.14]). CONCLUSIONS: In elderly women, low
fractional calcium absorption in the setting of low calcium intake increases
the
risk for hip fracture. Our findings support the hypothesis of type II
osteoporosis, which postulates that decreased calcium absorption is an
important
risk factor for hip fracture in older persons.
45: Med Hypotheses. 2000 Mar;54(3):4323.
How calcium from calcium carbonate and milk benefit peptic ulcer patients.
Wang X.
Calcium from calcium containing antacids and milk enhance the integrity
of
gastrointestinal mucosa and mucus, as it is the natural linker agent of
these
structures, which strengthens their defense function. Copyright 2000 Harcourt
Publishers Ltd.
PMID 10783482
46: Cochrane Database Syst Rev. 2000;(2):CD000952.
Calcium and vitamin D for corticosteroidinduced osteoporosis.
Homik J, SuarezAlmazor ME, Shea B, Cranney A, Wells G, Tugwell P.
OBJECTIVES: To assess the effects of calcium and vitamin D compared to
calcium
alone or placebo in the prevention of bone loss in patients taking systemic
corticosteroids. SEARCH STRATEGY: We searched the Cochrane Musculoskeletal
trials register, Cochrane Controlled Trials Register, EMBASE and Medline
up to
1996. We also conducted a hand search of abstracts from various scientific
meetings and reference lists of selected trials. SELECTION CRITERIA: All
randomized trials comparing calcium and vitamin D to calcium alone or
placebo in
patients taking systemic corticosteroids. DATA COLLECTION AND ANALYSIS:
Data was abstracted from trials by two investigators. Methodological quality
was assessed
in a similar manner. Analysis was performed using fixed effects models.
MAIN
RESULTS: Five trials were included, with 274 patients. The analysis was
performed at two years after starting calcium and vitamin D. There was
a
significant weighted mean difference (WMD) between treatment and control
groups
in lumbar (WMD 2.6 (95% CI 0.7, 4.5), and radial bone mineral density
(WMD 2.5
(95% CI 0.6, 4.4). The other outcome measures (femoral neck bone mass,
fracture
incidence, biochemical markers of bone resorption) were not significantly
different. REVIEWER'S CONCLUSIONS: This metaanalysis demonstrated a clinically
and statistically significant prevention of bone loss at the lumbar spine
and
forearm with vitamin D and calcium in corticosteroid treated patients.
Because
of low toxicity and cost all patients being started on corticosteroids
should
receive prophylactic therapy with calcium and vitamin D.
47: Kurume Med J. 2000;47(4):27983.
Effectiveness of an educational trial to encourage sufficient calcium
intake in
women college students.
Sueta K.
An educational trial to encourage sufficient calcium (Ca) intake was
conducted
on women college students who entered the college for dietitian either
in 1993
or in 1994. The trial's effectiveness was assessed by a prospective cohort
study. Two hundred and fifteen 18 or 19yearold students were assigned
into
two cohorts, i.e., a control cohort (CC) and an educated cohort (EC).
Both
groups received 3 surveys, i.e., at baseline, 1 week after, and 1 year
after the
Ca education, which was given only to the EC at baseline to encourage
sufficient
Ca intake. The amount of Ca taken by the CC did not significantly change
in the
3 surveys. The EC took a significantly larger amount of Ca 1 week after
and
maintained relatively larger amount of Ca 1 year after the Ca education.
These
results suggest some effectiveness of Ca education on the women college
students.
PMID 11197149
48: Ann Pharmacother. 1999 Dec;33(12):13568.
Calcium treatment for premenstrual syndrome.
Ward MW, Holimon TD.
OBJECTIVE: To evaluate the use of calcium supplementation in the treatment
of
premenstrual syndrome. DATA SOURCES: Clinical literature accessed through
MEDLINE (from January 1967 to September 1999). Key search terms included
calcium, PMS, and premenstrual. DATA SYNTHESIS: Up to 50% of women experience
some form of premenstrual syndrome. An evaluation of studies focusing
on calcium
in the management of premenstrual symptoms was conducted. CONCLUSIONS:
Calcium supplementation of 12001600 mg/d, unless contraindicated, should
be considered a sound treatment option in women who experience premenstrual
syndrome. The supplemental dose of calcium can be adjusted downward in
the few patients who
routinely consume large quantities of calcium in their diet.
49: J Endocrinol Invest. 1999 Dec;22(11):8526.
Importance of bioavailable calcium drinking water for the maintenance
of bone
mass in postmenopausal women.
Costi D, Calcaterra PG, Iori N, Vourna S, Nappi G, Passeri M.
The aim of this research was to establish the importance of calcium intake
through mineral water on vertebral bone density in women. To this purpose,
we
examined 255 women divided into two groups: those regularly drinking a
high
calcium content mineral water (group A; no.=175) and those using different
type
of water with a lower calcium content (group B; no.=80). Their dietary
daily
calcium intake was determined by means of a validated questionnaire (N.I.H.
Consensus statement) and vertebral bone density was measured by DualEnergy
Xray absorptiometry (Unigammaplus ACN densitometer). Women in group A
ingested
a significantly higher quantity of calcium in water than women in group
B (mean
difference 258 mg; 95% confidence limits: 147370 mg). The average bone
density
values were slightly but significantly higher in group A as compared to
group B
(mean+/SD: 1.044+0,15 vs 1.002+0,14; p=0.03). In addition to age, BMI
and
menopausal status, calcium intake was a significant predictor of spinal
BMD.
These 4 variables explained about 35% of the spinal BMD variance. When
the
analysis was repeated separately for pre and postmenopausal subjects,
calcium
remained a significant predictor in postmenopausal women (t=2.28; p=0.02),
but
not in premenopausal women. These results underline the importance of
a lifelong
daily calcium intake, resulting by the regular drinking of high bioavailable
calcium water, in order to maintain bone mass after the menopause, in
comparison
to the use of a lower content calcium water.
PMID 10710273
50: J Intern Med. 1999 Oct;246(4):35761.
The effect of various hormonal preparations and calcium supplementation
on bone
mass in early menopause. Is there a predictive value for the initial bone
density and body weight?
Pines A, Katchman H, Villa Y, Mijatovic V, Dotan I, Levo Y, Ayalon D.
OBJECTIVES: To compare the effect of various oestrogen and oestrogen/progestin
preparations on bone density over a 2year followup period in early
postmenopausal women. SETTING: A retrospective study on 315 women followed
in a
menopause clinic. DESIGN: Anteroposterior lumbar spine bone densitometry
was
performed at baseline and between 18 and 24 months (mean 22 months) after
initiation of hormone therapy. Participants were divided into six groups:
women
taking conjugated equine oestrogen (CEE) (n = 30); CEE plus sequential
monthly
medroxyprogesterone acetate (MPA) (n = 52); CEE plus sequential bimonthly
MPA (n
= 51); oral estradiol plus sequential monthly norethisterone acetate (n
= 52);
transdermal estradiol plus sequential monthly MPA (n = 30). A control
group (n =
100) was composed of nonusers of hormones. RESULTS: Hormone users, as
a whole (n
= 215), increased their bone mineral density (BMD) by 2.9% (4.8) as compared
to
the controls who lost 3.5% (3.4; P < 0. 001). There were similar gains
in BMD
amongst the five study groups. Calcium supplementation was associated
with
better results in all women: users of hormones and calcium had a gain
in BMD of
4.5% (4.8) compared to only 1.5% (4.5) in those on hormones but without
calcium
(P < 0.001); amongst the controls, women using calcium lost 1.4% (2.
4), whilst
nonusers of calcium lost 3.7% (2.4; P < 0.001). A doseresponse curve
was found
between basal BMD and the effect of hormone therapy: women with osteoporosis
(Tscore <75%) demonstrated the largest increase in BMD 6.3% (4.6),
osteopenia
(Tscore 7585%) was associated with a gain of 3.2% (5.6), lowborderline
values
(Tscore 86100%) gave a modest increase of 1.3% (4.3), and those with more
than
average BMD values (Tscore >100%) actually lost bone despite hormone
treatment
[2.1% (4.1)]. CONCLUSIONS: All hormone regimens had a similar bone conserving
effect. Basal BMD value may serve as a predictor for the success of treatment.
Calcium supplementation should be recommended in all postmenopausal women.
PMID 10583706
51: J Assoc Physicians India. 1999 Sep;47(9):86973.
Effect of protein and phosphate restricted and calcium and alphacalcidol
supplemented diet on renal and parathyroid functions and protein status
in
chronic renal failure patients.
Nand N, Aggarwal HK, Anupam, Sharma M.
OBJECTIVE: To assess the effect of low protein (0.6 g/kg/day), low phosphate
(510 mg/kg/day) diet with calcium (600 mg/day) and alphaD3 (0.5 microgram/day)
supplementation on renal and parathyroid functions in patients with chronic
renal failure (CRF). METHODS: The study included 20 adult patients of
CRF,
maintained on diet therapy alone. The patients were followed up for renal
and
parathyroid functions and protein status for 6 months at monthly interval.
RESULTS: There was symptomatic improvement in 88% patients. Blood urea
and serum
creatinine decreased significantly (p < 0.001 and < 0.01, respectively)
and the
slope of inverse serum creatinine against time changed to static or an
upslope.
Glomerular filtration rate (GFR) improved from a basal value of 29.35
+/ 18.2
ml/min to 39.25 +/ 27 ml/min after 6 months. Serum parathyroid hormone
(PTH)
level of 197.65 +/ 133.7 pg/ml and post treatment level of 254.55 +/ 217.19
after 6 months were not different (p > 0.05). Serum calcium remained
stationary
with a slight increase in serum phosphorus. Phosphorus had a negative
correlation with calcium and GFR, whereas calcium had a negative correlation
with PTH and phosphorus. PTH had a positive correlation with phosphorus
and
negative with GFR and calcium. CONCLUSION: There was an improvement in
renal
functions without any deleterious effect on the protein status of the
patients
of CRF. Also, there was halting of parathyroid dysfunction especially
in those
patients where there was no evidence of preexisting hyperparathyroidism.
Hence,
dietry management should be strictly enforced in CRF patients early in
the
course of disease.
52: Stroke. 1999 Sep;30(9):17729.
Prospective study of calcium, potassium, and magnesium intake and risk
of stroke
in women.
Iso H, Stampfer MJ, Manson JE, Rexrode K, Hennekens CH, Colditz GA, Speizer
FE,
Willett WC.
BACKGROUND AND PURPOSE: High intakes of calcium, potassium, and magnesium
have been hypothesized to reduce risks of cardiovascular disease, but
only a few
prospective studies have examined intakes of these cations in relation
to risk
of stroke. METHODS: In 1980, 85 764 women in the Nurses' Health Study
cohort,
aged 34 to 59 years and free of diagnosed cardiovascular disease and cancer,
completed dietary questionnaires from which we calculated intakes of calcium,
potassium, and magnesium. By 1994, after 1.16 million personyears of followup,
690 incident strokes (129 subarachnoid hemorrhages, 74 intraparenchymal
hemorrhages, 386 ischemic strokes, and 101 strokes of undetermined type)
had
been documented. RESULTS: Intakes of calcium, potassium, and magnesium
were each
inversely associated with age and smokingadjusted relative risks of ischemic
stroke, excluding embolic infarction of nonatherogenic origin (n=347).
Adjustment for other cardiovascular risk factors, including history of
hypertension, attenuated these associations, particularly for magnesium
intake.
In a multivariate analysis, women in the highest quintile of calcium intake
had
an adjusted relative risk of ischemic stroke of 0.69 (95% CI, 0.50 to
0.95; P
for trend=0.03) compared with those in the lowest quintile; for potassium
intake
the corresponding relative risk was 0.72 (95% CI, 0.51 to 1.01; P for
trend=0.10). Further simultaneous adjustment for calcium and potassium
intake
suggested an independent association for calcium intake. The association
of risk
with calcium intake did not appear to be log linear; the increase in risk
was
limited to the lowest quintile of intake, and intakes > approximately
600 mg/d
did not appear to reduce risk of stroke further. The inverse association
with
calcium intake was stronger for dairy than for nondairy calcium intake.
Intakes
of calcium, potassium, and magnesium were not related to risk of other
stroke
subtypes. CONCLUSIONS: Low calcium intake, and perhaps low potassium intake,
may
contribute to increased risk of ischemic stroke in middleaged American
women.
It remains possible that women in the lowest quintile of calcium intake
had
unknown characteristics that made them susceptible to ischemic stroke.
PMID 10471422
53: N Engl J Med. 1999 Aug 19;341(8):5638.
A comparison of calcium, vitamin D, or both for nutritional rickets in
Nigerian
children.
Thacher TD, Fischer PR, Pettifor JM, Lawson JO, Isichei CO, Reading JC,
Chan GM.
BACKGROUND: Nutritional rickets remains prevalent in many tropical countries
despite the fact that such countries have ample sunlight. Some postulate
that a
deficiency of dietary calcium, rather than vitamin D, is often responsible
for
rickets after infancy. METHODS: We enrolled 123 Nigerian children (median
age,
46 months) with rickets in a randomized, doubleblind, controlled trial
of 24
weeks of treatment with vitamin D (600,000 U intramuscularly at enrollment
and
at 12 weeks), calcium (1000 mg daily), or a combination of vitamin D and
calcium. We compared the calcium intake of the children at enrollment
with that
of control children without rickets who were matched for sex, age, and
weight.
We measured serum calcium and alkaline phosphatase and used a 10point
radiographic score to assess the response to treatment at 24 weeks. RESULTS:
The
daily dietary calcium intake was low in the children with rickets and
the
control children (median, 203 mg and 196 mg, respectively; P=0.64). Treatment
produced a smaller increase in the mean (+/SD) serum calcium concentration
in
the vitamin D group (from 7.8+/0.8 mg per deciliter [2.0+/0.2 mmol per
liter]
at base line to 8.3+/0.7 mg per deciliter [2.1+/0.2 mmol per liter] at
24
weeks) than in the calcium group (from 7.5+/0.8 [1.9+/0.2 mmol per liter]
to
9.0+/0.6 mg per deciliter [2.2+/0.2 mmol per liter], P<0.001) or the
combinationtherapy group (from 7.7+/1.0 [1.9+/0.25 mmol per liter] to
9.1+/0.6 mg per deciliter [2.3+/0.2 mmol per liter], P<0.001). A greater
proportion of children in the calcium and combinationtherapy groups than
in the
vitamin D group reached the combined end point of a serum alkaline phosphatase
concentration of 350 U per liter or less and radiographic evidence of
nearly
complete healing of rickets (61 percent, 58 percent, and 19 percent,
respectively; P<0.001). CONCLUSIONS: Nigerian children with rickets
have a low
intake of calcium and have a better response to treatment with calcium
alone or
in combination with vitamin D than to treatment with vitamin D alone.
PMID 10451461
54: Gen Pharmacol. 1999 Aug;33(2):13741.
Taurine and calcium interaction in protection of myocardium exposed to
ischemic
reperfusion injury.
Oz E, Erbas D, Gelir E, Aricioglu A.
Department of Physiology, Faculty of Medicine, Gazi University, Ankara,
Turkey.
We aimed to investigate the cardioprotective role of taurine with low
calcium
level against reperfusion damage by adding taurine to extracellular fluid.
Guineapig hearts were mounted on Langendorf perfusion apparatus and different
compositions of perfusion solutions were prepared for each experimental
group.
After 20 min of normothermic ischemia the hearts were reperfused. Preischemic,
postischemic and postreperfusion percentage changes of heart rate and
contractile force were compared. Postreperfusion tissue weight, malondialdehyde
(MDA) and prostaglandin Elike activity (PGElike activity) were assessed.
Taurineadded lowcalcium perfusion solution significantly decreased the
postischemic myocardial injury.
PMID 10461851
55: Adv Nurse Pract. 1999 Jul;7(7):2631, 80.
An expanding landscape. Osteoporosis. Treatment options today.
Meiner SE.
Choices for osteoporosis therapy have expanded within the past 5 years.
This
article provides an overview of currently available therapy options. Exogenous
estrogen can prevent and treat osteoporosis and is available in several
delivery
routes. Calcitonin is also designed to reduce bone loss in osteoporosis.
Bisphosphonates such as alendronate prevent bone resorption by inhibiting
osteoclasts and causing increased osteoclast cell death. Raloxifene is
a
selective estrogen receptor modulator and is the newest osteoporosis medication
on the market. It may also have beneficial effects on breast cancer risk.
All
postmenopausal women should obtain 1,000 mg to 1,500 mg of calcium and
400 IU to
800 IU of vitamin D every dayregardless of any prescription therapy regimen
for osteoporosis. They should also perform weightbearing exercise, such
as
walking, for 20 to 30 minutes every day or for 1 hour three times a week.
56: Clin Ther. 1999 Jun;21(6):105872.
Supplemental calcium for the prevention of hip fracture: potential
healtheconomic benefits.
Bendich A, Leader S, Muhuri P.
We assessed the costeffectiveness of daily calcium supplementation for
the
prevention of primary osteoporotic hip fractures. The assessment was based
on
our metaanalysis of the published relativerisk estimates from 3 doublemasked,
placebocontrolled, clinical trials and our analysis of raw data from the
National Health and Nutrition Examination Survey 19881994 on the daily
intake
of calcium supplements by adults in the United States. These data were
then used
to estimate the preventable proportion of hip fractures. The 1995 National
Hospital Discharge Survey database provided the number and demographic
characteristics of patients discharged with a primary diagnosis of hip
fracture,
as well as their discharge destination. The 1990 itemized costs of hip
fractures, as estimated by the US Congress Office of Technology Assessment,
were
inflated to 1995 dollars using the medical care component of the Consumer
Price
Index. Using these inflated itemized costs, we then estimated the weighted
average expenditures, reflecting both the types of services associated
with
specific hospitaldischarge destinations and the demographic characteristics
of
discharged patients. The cost of supplements containing 1200 mg/d of elemental
calcium for the mean duration (34 months) of the 3 clinical trials was
calculated on the basis of 1998 unitprice and marketshare data for 6
representative products. For 1995, the data indicate that 290,327 patients
aged
> or =50 years were discharged from US hospitals with a primary diagnosis
of hip
fracture, at our estimated direct cost of $5.6 billion. Based on the risk
reductions seen in the 3 trials, we estimated that 134,764 hip fractures
and
$2.6 billion in direct medical costs could have been avoided if individuals
aged
> or =50 years consumed approximately 1200 mg/d of supplemental calcium.
Additional savings could be expected, because this intervention is also
associated with significant reductions in the risk for all nonvertebral
fractures. Comparing the cost of calcium with the expected medical savings
from
hip fractures avoided, it is costeffective to give 34 months of calcium
supplementation to women aged > or =75 years in the United States.
If, as the
published studies suggest, shorter periods of supplementation result in
an
equivalent reduction in the risk of hip fractures, calcium supplementation
becomes costeffective for all adults aged > or =65 years in the United
States.
The data support encouraging older adults to increase their intake of
dietary
calcium and to consider taking a daily calcium supplement. Even small
increases
in the usage rate of supplementation are predicted to yield significant
savings
and to reduce the morbidity and mortality associated with hip fracture
at an
advanced age.
PMID 10440627
57: J Am Diet Assoc. 1999 May;99(5):5913.
Calcium supplementation and exercise increase appendicular bone density
in
anorexia: a case study.
Brooks ER, Howat PM, Cavalier DS.
PMID 10333781
58: Scand J Clin Lab Invest. 1999 Apr;59(2):837.
Short and longterm uses of calcium acetate do not change hair and serum
zinc
concentrations in hemodialysis patients.
Hwang SJ, Chang JM, Lee SC, Tsai JH, Lai YH.
Calcium acetate (CaAc) acutely decreases absorption of concomitantly
administered zinc gluconate (Hwang et al., AJKD 1992), but its longterm
effect
on zinc metabolism has not been studied. This study is intended to elucidate
whether use of CaAc as phosphate binder on a daily basis affects zinc
status in
hemodialysis (HD) patients. Effects of CaAc on serum zinc were studied
in 44 HD
patients for 8 weeks (shortterm). In 10 of these patients, the changes
of serum
and hair zinc were followed for 8 months (longterm). The daily dose of
CaAc
contained 25.35 mmol elemental calcium. Serum and hair zinc concentrations
were
measured by atomic absorptiometry. Our results were as follows: (i) in
the
shortterm study, serum zinc concentrations did not show a significant
difference compared to the baseline; (ii) in the longterm study, serum
zinc
concentrations showed no significant difference between different time
points
(11.0+/0.5 in the beginning, 11.9+/0.4 after 2 months, 11.4+/0.4 after
4
months and 11.3+/0.5 micromol/L after 8 months, n=10). However, these
values
were all significantly lower than in the normal controls (15.7+/0.5 micromol/L,
n=16); (iii) hair zinc content was not significantly different from the
baseline
level (2.7+/0.1 in the beginning, 2.4+/0.1 after 2 months, 2.6+/0.2 after
4
months, 3.1+/0.1 micromol/g hair, and from that of normal controls, 2.7+/0.2
micromol/g hair). In conclusion, daily application of CaAc does not
significantly interfere with zinc absorption and storage in HD patients.
However, the comparable hair zinc content in the presence of decreased
serum
zinc concentrations indicates that the metabolic processing of zinc in
HD
patients is different from that of normal individuals.
PMID 10353320
59: J Nutr. 1999 Mar;129(3):70711.
Calcium does not inhibit iron absorption or alter iron status in infant
piglets
adapted to a high calcium diet.
Wauben IP, Atkinson SA.
The purpose of this study was to investigate whether a dietary calcium:iron
ratio similar to that often consumed by premature human infants inhibits
iron
absorption in infant piglets adapted to a high calcium diet. Male Yorkshire
piglets were randomized at 3 to 4 d of age to a high calcium diet (4.67
g/L =
HC) or a normal calcium diet (2.0 g/L = NC) and fed for 2 to 2.5 wk. An
iron
dextran injection was administered in amounts to achieve a marginal state
of
iron repletion to simulate iron status of premature infants. In vivo iron
absorption from the diet was determined using the radiotracers 55Fe and
59Fe and
whole body counting. Calcium:iron interactions at absorption sites in
piglets
fed HC and NC were investigated by measurements of timedependent 59Fe
uptake in
response to different calcium:iron ratios in vitro in brush border membrane
vesicles (BBMV). In vivo iron absorption from the diet did not differ
between NC
and HC diet groups [57 +/ 8% versus 55 +/ 17% (mean +/ SD), respectively].
Iron status and iron contencentrations in spleen, liver, intestine, kidney
and
heart did not differ between diet groups. Iron uptake in BBMV was significantly
reduced by calcium in both HC and NC (P < 0.001); but there were no
significant
differences in iron uptake in response to different calcium:iron ratios
between
HC and NC. With feeding a HC diet for 2 wk there may be an adaptive response
to
counteract the inhibitory effects of calcium on iron absorption, thus
resulting
in similar in vivo iron absorption and iron status irrespective of the
1.3fold
difference in dietary calcium:iron ratio between piglet groups. However,
future
studies are needed to determine the specific sites of calcium:iron interactions
and adaptation mechanisms. Since the calcium:iron ratios used in this
study
reflect the usual calcium:iron ratios in diets for premature infants,
it is
unlikely that interactive effects of calcium with iron will compromise
iron
status in this infant population when diets are supplemented with calcium.
60: Nutr Rev. 1999 Mar;57(3):848.
The effects of potassium, magnesium, calcium, and fiber on risk of stroke.
Suter PM.
Stroke mortality represents the third leading cause of death worldwide,
after
coronary artery disease and cancer. High blood pressure is a major risk
factor
for stroke. A recent study has identified potassium, magnesium, and fiber
as
significant modulators of stroke risk in men. The protective effects were
particularly pronounced in hypertensive subjects. The observed protection
may be
due to direct and indirect effects of these nutrients on blood pressure
and
regulatory functions, such as endothelial function. A high intake of these
nutrients, singularly or in combination, is associated with a more healthful
overall lifestyle. The best strategy to achieve a high intake of these
nutrients
is a diet rich in fruits and vegetables.
61: Dis Colon Rectum. 1999 Feb;42(2):2127.
Vitamin and calcium supplement use is associated with decreased adenoma
recurrence in patients with a previous history of neoplasia.
Whelan RL, Horvath KD, Gleason NR, Forde KA, Treat MD, Teitelbaum SL,
Bertram A,
Neugut AI.
INTRODUCTION: Although some have suggested that certain vitamins or calcium
supplements may reduce adenoma recurrence, our own prior retrospective
study
found no such effects. The purpose of this casecontrol study was to further
investigate whether regular vitamin or calcium supplement intake influenced
the
incidence of recurrent adenomatous polyps in patients with previous neoplasia
who were undergoing followup colonoscopy. METHODS: This study enrolled
1,162
patients who underwent colonoscopy by one of three surgeons at
ColumbiaPresbyterian Medical Center in New York City between March 1993
and
February 1997. Of these patients 448 (250 males) had a previous diagnosis
of
colorectal neoplasia (cancer, adenomas, or dysplasia). Of these, 183 (40.8
percent) had an adenoma at the index colonoscopy. Information was collected
on
personal and family history of colonic diseases, cigarette smoking, medication,
and vitamin and micronutrient supplement usage on a questionnaire that
was
completed by the patients before the colonoscopy. Odds ratios were obtained
by
unconditional logistic regression analysis, adjusting for age and gender,
and
used adenoma recurrence at index colonoscopy as the outcome. RESULTS:
The mean
interval between colonoscopic examinations was 37 months for the recurrent
adenoma group and 38 months for the nonrecurrent group of patients (P
= not
significant). In this casecontrol study we found a protective effect for
the
use of vitamin supplements in general (any vitamin) on the recurrence
of
adenomas (odds ratio, 0.41; 95 percent confidence interval, 0.270.61).
Specifically, this protective effect was observed for the use of multivitamins
(odds ratio, 0.47; 95 percent confidence interval, 0.310.72), vitamin
E (odds
ratio, 0.62; 95 percent confidence interval, 0.390.98), and for calcium
supplementation (odds ratio, 0.51; 95 percent confidence interval, 0.270.96).
Nonsignificant protective effects were noted for carotene/vitamin A, vitamin
D,
and vitamin C. CONCLUSIONS: The use of multivitamins, vitamin E, and calcium
supplements were found to be associated with a lower incidence of recurrent
adenomas in a population of patients with history of previous colonic
neoplasia.
Prospective, randomized trials are needed to better assess the impact
of these
agents and to determine whether the use of these supplements is associated
with
a protective effect against recurrent adenomas.
PMID 10211498
62: J Gynecol Obstet Biol Reprod (Paris). 1999 Feb;28(1):735.
[Exanthematic pustulosis of pregnancy: favorable evolution using calcium
and
vitamin D2]
Michel JL, Perrot JL, Varlet MN, Fond L, Seffert P, Cambazard F.
A 26yearold pregnant woman was hospitalized in an emergency setting for
a skin
eruption. She had developed pustules distributed on round patchlike areas
of
rash localized at the umbilicus and the larger skin folds. She was given
calcitriol and calcium with good results. Systemic steroids are usually
given
for exanthematic pustulosis of pregnancy but with variable efficacy. Few
cases
of successful treatment with calcium and vitamin D have been reported.
We
suggest this alternative treatment could be useful in other cases.
63: Ann N Y Acad Sci. 1999;889:1207.
Preclinical and early human studies of calcium and colon cancer prevention.
Lipkin M.
Colorectal cancer continues to be a major cause of tumor mortality in
the United
States and other countries; despite attempts to improve the screening
of
highrisk populations, the incidence of this disease is still very high.
Therefore, chemoprevention continues to be an important goal for the primary
prevention of colorectal cancer. Among recent chemopreventive approaches,
the
administration of calcium and vitamin D continue to be evaluated in both
preclinical and clinical studies. Many experimental findings described
below
have indicated associations between high calcium and vitamin D intake
and
decreased risk for colorectal cancer.
64: Ann N Y Acad Sci. 1999;889:13845.
Calcium supplements and colorectal adenomas. Polyp Prevention Study Group.
Baron JA, Beach M, Mandel JS, van Stolk RU, Haile RW, Sandler RS, Rothstein
R,
Summers RW, Snover DC, Beck GJ, Frankl H, Pearson L, Bond JH, Greenberg
ER.
Experimental and observational findings suggest that calcium intake may
protect
against colorectal neoplasia. To investigate this hypothesis, we conducted
a
randomized, doubleblind trial of colorectal adenoma recurrence. Nine hundred
thirty patients with a recent history of colorectal adenomas were randomly
given
calcium carbonate (3 gm daily; 1200 mg elemental calcium) or placebo,
with
followup colonoscopies one and four years after the qualifying examination.
The
main analysis focused on new adenomas found after the first followup endoscopy,
up to (and including) the second followup examination. Risk ratios of
at least
one recurrent adenoma and ratios of the average numbers of adenomas were
calculated as measures of calcium effect. There was a lower risk of recurrent
adenomas in subjects assigned calcium. Eight hundred thirtytwo patients
had two
followup examinations and were included in the main analysis; the adjusted
risk
ratio of one or more adenomas was 0.81 (95% CI 0.67 to 0.99); the adjusted
ratio
of the average numbers of adenomas was 0.76 (95% CI 0.60 to 0.96). Among
subjects who had at least one followup colonoscopy, the adjusted risk
ratio of
one or more recurrent adenomas was 0.85 (95% CI 0.74 to 0.98). The effect
of
calcium seemed independent of initial dietary fat and calcium intake.
No
toxicity was associated with supplementation. These findings indicate
that
calcium supplementation has a modest protective effect against colorectal
adenomas, precursors of most colorectal cancers.
65: Am J Clin Nutr. 1998 Dec;68(6 Suppl):1394S1399S.
Prevention of precancerous colonic lesions in rats by soy flakes, soy
flour,
genistein, and calcium.
Thiagarajan DG, Bennink MR, Bourquin LD, Kavas FA.
The main purpose of this research was to determine whether diets containing
soy
products would inhibit the early stages of azoxymethaneinduced colon cancer
in
F344 rats. Additional objectives were to determine whether feeding starch
instead of sucrose, feeding additional calcium (0.5% compared with 0.1%),
or
feeding a lowfiber powdered enteral formula would influence early colon
carcinogenesis. Colon cancer was initiated with 2 injections of azoxymethane
(15
mg/kg body wt) and a 12wk dietary treatment period was started 1 wk after
the
second injection. Precancerous colon lesions were assessed as foci with
aberrant
crypts (FAC). The mean numbers of FAC were 133 [soy concentrate (low
concentration of phytochemicals)], 111 (starch substituted for sucrose),
98
[fullfat soy flakes (whole soybeans)], 87 (defatted soy flour), 77 (0.015%
genistein), and 70 (0.5% Ca). The soy flour and fullfat soy flake diets
contained 0.049% genistein derivatives (primarily glycosides), but were
less
effective in inhibiting the formation of FAC than the diet containing
0.015%
genistein (as the aglycone). Eating soybeans and soy flour may reduce
the early
stages of colon cancer.
PMID 9848506
66: J Clin Endocrinol Metab. 1998 Nov;83(11):381725.
Calcium supplementation prevents seasonal bone loss and changes in biochemical
markers of bone turnover in elderly New England women: a randomized
placebocontrolled trial.
Storm D, Eslin R, Porter ES, Musgrave K, Vereault D, Patton C, Kessenich
C,
Mohan S, Chen T, Holick MF, Rosen CJ.
Elderly women are at increased risk for bone loss and fractures. In previous
crosssectional and longitudinal studies of women residing in northern
latitudes, bone loss was most pronounced during winter months and in those
consuming less than 1 g calcium per day. In this study we sought to test
the
hypothesis that calcium supplementation by either calcium carbonate or
dietary
means would prevent seasonal bone loss and preserve bone mass. Sixty older
postmenopausal women without osteoporosis were randomized to one of three
treatment arms: Dietary milk supplementation (D4 glasses of milk/day),
Calcium
carbonate (CaCO31000 mg/day in two divided doses), or placebo (P). After
2 yr,
placebotreated women consumed a mean of 683 mg/day of calcium and lost
3.0% of
their greater trochanteric (GT) bone mineral density (BMD) (P < 0.03
vs.
baseline); Dietary supplemented women averaged a calcium intake of 1028
mg/day
and sustained minimal loss from the GT (1.5%; P = 0.30), whereas CaCO3treated
women (total Ca intake, 1633 mg/day) suffered no bone loss from the GT
and
showed a significant increase in spinal and femoral neck BMD (P < 0.05).
Femoral
bone loss occurred exclusively during the two winters of the study (i.e.
total
loss, 3.2%; P < 0.02 in placebotreated women) with virtually no change
in GT
BMD during summer. Serum 25OH vitamin D declined by more than 20% (P <
0.001)
in all groups during the winter months but returned to baseline in summer;
PTH
levels rose approximately 20% (P < 0.001) during winter but did not
return to
baseline during the summers. Urine Ntelopeptide and osteocalcin levels
increased significantly but only in the Ptreated women and only during
winter.
Serum insulin growth factor binding protein 4, an inhibitory insulin growth
factor binding protein, rose 15% (P < 0.03) from summer to winter,
but this
increase was significant only in those women consuming <1000 mg/day
of calcium.
By multivariate analysis, total calcium intake was the strongest predictor
of
bone loss from the hip. Urinary Ntelopeptide also closely correlated with
GT
BMD but only during winter (P = 0.003). We conclude that calcium supplementation
prevents bone loss in elderly women by suppressing bone turnover during
the
winter when serum 25OH vitamin D declines and serum PTH increases. The
precise
amount of calcium necessary to preserve BMD in elderly women requires
further
studies, although in this study, at least 1000 mg/day of supplemental
calcium
was adequate prophylaxis against femoral bone loss.
67: Aging (Milano). 1998 Oct;10(5):38594.
Calcium, gammalinolenic acid and eicosapentaenoic acid supplementation
in
senile osteoporosis.
Kruger MC, Coetzer H, de Winter R, Gericke G, van Papendorp DH.
Recent animal work suggests that gammalinolenic acid (GLA) and eicosapentaenoic
acid (EPA) enhance calcium absorption, reduce excretion and increase calcium
deposition in bone. A pilot study was set up to test the interactions
between
calcium and GLA + EPA in humans. Sixtyfive women (mean age 79.5), taking
a
background diet low in calcium, were randomly assigned to GLA + EPA or
coconut
oil placebo capsules; in addition, all received 600 mg/day calcium as
the
carbonate. Markers of bone formation/degradation and bone mineral density
(BMD)
were measured at baseline, 6, 12 and 18 months. Twentyone patients were
continued on treatment for a second period of 18 months, after which BMD
(36
months) was measured. At 18 months, osteocalcin and deoxypyridinoline
levels
fell significantly in both groups, indicating a decrease in bone turnover,
whereas bone specific alkaline phosphatase rose indicating beneficial
effects of
calcium given to all the patients. Lumbar and femoral BMD, in contrast,
showed
different effects in the two groups. Over the first 18 months, lumbar
spine
density remained the same in the treatment group, but decreased 3.2% in
the
placebo group. Femoral bone density increased 1.3% in the treatment group,
but
decreased 2.1% in the placebo group. During the second period of 18 months
with
all patients now on active treatment, lumbar spine density increased 3.1%
in
patients who remained on active treatment, and 2.3% in patients who switched
from placebo to active treatment; femoral BMD in the latter group showed
an
increase of 4.7%. This pilot controlled study suggests that GLA and EPA
have
beneficial effects on bone in this group of elderly patients, and that
they are
safe to administer for prolonged periods of time.
68: Am J Vet Res. 1998 Aug;59(8):105562.
Effect of intravenous calcium administration on gentamicininduced
nephrotoxicosis in ponies.
Brashier MK, Geor RJ, Ames TR, O'Leary TP.
OBJECTIVE: To determine whether supplemental i.v. calcium administration
would
attenuate or prevent gentamicininduced acute renal failure, defined as
an
increase in serum creatinine concentration > or = 50% above baseline.
ANIMALS:
10 healthy pony mares. PROCEDURE: Pony mares were randomly assigned to
receive
calcium at a dosage of 20 mg/kg of body weight or saline solution i.v.,
twice
daily for 14 days. All pony mares received gentamicin at a dosage of 20
mg/kg
i.v. every 8 hours for 14 days. Gentamicin pharmacokinetic, serum biochemical,
and urinalysis data were measured every other day for the 14day study
period.
Renal histologic examination was performed, and results were scored at
the end
of the 14day period. RESULTS: 4 of 5 mares not receiving calcium
supplementation developed acute renal failure. Only 1 of the 5 mares receiving
calcium supplementation developed acute renal failure. Over the course
of the
study, pony mares receiving calcium supplementation had significantly
fewer
changes in urinalysis variables, and significantly less microscopic renal
damage. CONCLUSION: Daily i.v. administration of calcium attenuated
gentamicininduced acute renal failure. CLINICAL RELEVANCE: Calcium
supplementation may help diminish the risk of acute renal failure associated
with aminoglycoside antibiotics.
69: Endocrinol Metab Clin North Am. 1998 Jun;27(2):38998.
The roles of calcium and vitamin D in the prevention of osteoporosis.
Reid IR.
Calcium supplementation produces small beneficial effects on bone mass
throughout postmenopausal life and may reduce fracture rates by more than
this
change would predictpossibly by as much as 50%. There is little reason
to use
vitamin D in young populations that are replete in this compound, but
in the
elderly at risk of vitamin D deficiency, there is now evidence of significant
reductions in nonvertebral fracture rates from physiologic replacement
regimens.
Some of the most substantial reductions in fracture rates have been found
with
combined therapy with calcium and vitamin D, and in these protocols it
is not
clear which is the principal active agent or whether, in fact, the combination
is necessary for optimal antifracture efficacy.
70: Jpn Heart J. 1998 May;39(3):34753.
Acute antihypertensive effects of calcium channel blockers are not affected
by
calcium supplementation in patients with essential hypertension.
Sato K, Dohi Y, Miyagawa K, Kojima M.
The study was designed to investigate whether the acute antihypertensive
effects
of calcium channel blockers are affected by calcium supplementation in
patients
with essential hypertension. The antihypertensive effects of calcium channel
blockers (oral manidipine or intravenous nicardipine) were studied before
and
during calcium supplementation (1200 mg/day for 8 weeks) in 30 hospitalized
patients with essential hypertension. The averages of systolic and diastolic
blood pressure during a 24hour period were not decreased by calcium
supplementation. The acute antihypertensive effects of the calcium channel
blockers nicardipine (0.25, 0.5, 1.5, 2.0 micrograms/kg/min, intravenous
infusion) or manidipine (20 mg, once a day, orally) were not enhanced
by calcium
supplementation. Thus, calcium channel blockers can be safely combined
with
calcium supplementation in terms of blood pressure.
PMID 9711186
71: Ann Thorac Surg. 1998 Apr;65(4):106570.
Calcium preconditioning in human myocardium.
Cain BS, Meldrum DR, Meng X, Shames BD, Banerjee A, Harken AH.
BACKGROUND: Ischemic stress and other protein kinase C (PKC)linked receptor
stimuli can induce rapid cardiac protection against ischemiareperfusion
injury.
We and others have demonstrated that exogenous calcium (Ca2+) pretreatment
confers PKCmediated cardiac functional and infarct protection in animal
models,
but it remains unknown whether Ca2+ preconditioning confers similar postischemic
functional protection in human myocardium, and, if so, whether the mechanism
is
mediated by PKC. We postulated that Ca2+ preconditioning confers ischemic
tolerance to human myocardium by a PKCdependent mechanism. METHODS: Human
atrial trabeculae were suspended in organ baths and paced at 1 Hz, and
force
development was recorded. After 90 minutes of equilibration, all trabeculae
were
subjected to ischemia (45 minutes) and reperfusion (120 minutes). Exogenous
CaCl2 (3.0 mmol/L for 5 minutes) or vehicle (saline solution) was administered
before simulated ischemia, with or without concurrent PKC inhibition
(bisindolylmaleimide I, 150 nmol/L). RESULTS: Ischemiareperfusion resulted
in
decreased postischemic developed force, Ca2+ preconditioning protected
human
myocardium against ischemiareperfusion injury (p < 0.05 versus control
ischemiareperfusion), and concurrent PKC inhibition abolished the salutary
effect of Ca2+ preconditioning in human myocardium (p < 0.05 versus
Ca2+
preconditioning). CONCLUSIONS: Preconditioning with Ca2+ represents a
potent
means of accessing PKCmediated protection of the human myocardium against
ischemiareperfusion injury.
PMID 9564929
72: Cancer Epidemiol Biomarkers Prev. 1998 Apr;7(4):2915.
Dietary and supplemental calcium and the recurrence of colorectal adenomas.
Hyman J, Baron JA, Dain BJ, Sandler RS, Haile RW, Mandel JS, Mott LA,
Greenberg ER.
The association between calcium intake and the risk of colorectal neoplasia
remains controversial. This analysis prospectively investigated the association
between dietary and supplemental calcium intake and recurrent colorectal
adenomas. Participants were part of a multicenter, randomized clinical
trial of
antioxidant vitamins. The study endpoints were adenomas detected between
surveillance colonoscopies conducted at approximately 1 year and 4 years
after
study entry. Baseline intake of energyadjusted calcium derived from a
food
frequency questionnaire was used as the main exposure of interest. Calcium
supplement use was assessed by semiannual questionnaires. Logistic regression
was used to compute odds ratios and 95% confidence limits, and Poisson
regression was used to estimate rate ratios. Subjects in the fifth quintile
of
dietary calcium had an adjusted odds ratio of 0.72 (95% confidence interval,
0.431.22) compared to those in the lowest quintile. Investigation of the
numbers of adenomas yielded stronger findings: the rate ratio for the
fifth
quintile versus the first was 0.63 (95% confidence interval, 0.391.02).
Dietary
calcium seemed to have a greater effect among individuals with a highfat
diet
than among those with a lowfat diet; however, the interaction was not
statistically significant. Use of calcium supplements was not related
to adenoma
recurrence. These results suggest that a high calcium intake may be associated
with a reduction in risk of recurrent adenomas, especially among individuals
on
a highfat diet.
73: Obstet Gynecol. 1998 Apr;91(4):58590.
Prevention of preeclampsia by linoleic acid and calcium supplementation:
a
randomized controlled trial.
Herrera JA, ArevaloHerrera M, Herrera S.
OBJECTIVE: To determine the effect of low doses of linoleic acid and
calcium on
prostaglandin (PG) levels and the efficacy of this treatment in the prevention
of preeclampsia. METHODS: In a randomized, doubleblind, placebocontrolled
study we treated 86 primigravidas with risk factors for preeclampsia (high
biopsychosocial risk [above 3 points], positive rollover test, and high
mean
blood pressure [above 85 mmHg)] with daily doses of either 450 mg linoleic
acid
and 600 mg calcium (n=43) or 450 mg starch and 600 mg lactose placebo
(n=43)
during the third trimester of pregnancy. RESULTS: Four women in the experimental
group (9.3%) developed preeclampsia compared with 16 (37.2%) controls
(relative
risk 0.25, 95% confidence interval 0.09, 0.69, P < .001). The median
serum
levels of PGE2 after 4 weeks of treatment increased by 106% in the experimental
group (P=.03) and decreased by 33% in the control group (P=.02). The median
ratio between thromboxane B2 and PGE2 decreased by 40% in the experimental
group
(P=.02) and increased by 18% in the control group (P=.14). No significant
differences were observed in the median ratio between thromboxane B2 and
6keto
PGF1alpha in either group. No serious maternal or neonatal side effects
of
treatment occurred in either group. CONCLUSION: The administration of
low daily
doses of linoleic acid and calcium during the third trimester of pregnancy
reduced the incidence of preeclampsia significantly in women at high risk,
possibly by correcting the PGE2 levels.
74: J Nutr. 1998 Mar;128(3):6405.
Dietary restriction of energy and calcium alters bone turnover and density
in
younger and older female rats.
Talbott SM, Rothkopf MM, Shapses SA.
To determine the influence of weight loss with or without adequate calcium
intake on bone turnover and density, we examined the influence of dietary
restriction of calcium or energy on body weight (BW), bone mineral density
(BMD)
and bone turnover in both younger (3 mo) and older (10 mo) female rats
(n = 66).
Diets were designed to allow feeding at two levels of calcium intake (normal
=
78 mg/d and low = 15 mg/d) and two levels of energy intake (normal and
40%
restriction) while keeping the intake of protein, fat, fiber, vitamins
and other
minerals equal between groups. Thus rats received either a control diet
(CNTL),
a diet restricted in calcium, energy or both for 9 wk. Energy restriction
reduced BW 521% (P < 0.01) and elevated bone formation 1020% (P <
0.05) in
both age groups. Bone resorption was 2040% above CNTL values (P < 0.05),
in
rats fed all three restricted diets. In younger rats, BMD increased over
time in
all groups (P < 0.05), but final BMD was lower in calcium restricted
groups
compared with CNTL (P < 0.01). In older rats, CNTL had a significantly
greater
final BMD (P < 0.05) than dietrestricted groups. These data indicate
that, in
both younger and older rats, dietary restriction of calcium or energy
results in
an elevated rate of bone turnover. BMD is compromised by calcium restriction
in
both younger and older rats, whereas only older rats were negatively influenced
by dietary energy restriction. Thus the present study indicates a detrimental
effect of lowenergy diets, as well as inadequate calcium intake, on bone
density in mature rats.
PMID 9482775
75: J Nutr Sci Vitaminol (Tokyo). 1996 Aug;42(4):31323.
Effects of calcium gluconate on the utilization of magnesium and the
nephrocalcinosis in rats fed excess dietary phosphorus and calcium.
Chonan O, Takahashi R, Kado S, Nagata Y, Kimura H, Uchida K, Watanuki
M.
The effects of calcium gluconate on the utilization of magnesium and
nephrocalcinosis in male Wistar rats made magnesiumdeficient by adding
excess
dietary phosphorus (1.195 g of phosphorus/100 g of diet) and calcium (1.04
g of
calcium/100 g of diet) were compared with the effects of calcium carbonate.
The
effects of dietary magnesium concentration on the magnesium status and
nephrocalcinosis were also examined. Adding excess dietary phosphorus
and
calcium decreased the apparent magnesium absorption ratios and the
concentrations of magnesium in the serum and femur and increased the deposition
of calcium in the kidney, and the low magnesium condition (0.024 g of
magnesium/100 g of diet) aggravated the deposition of calcium and the
low
magnesium status. The apparent magnesium absorption ratios and femur magnesium
concentration in the rats fed a calcium gluconate diet (an equimolar mixture
of
calcium gluconate and calcium carbonate was used as a source of calcium)
were
significantly higher than in the rats fed a calcium carbonate diet (only
calcium
carbonate was used as a source of calcium), irrespective of dietary magnesium
concentration. Dietary calcium gluconate lessened the accumulation of
calcium in
the kidney and increased the serum magnesium concentration compared with
dietary
calcium carbonate, when the rats were fed the normal magnesium diet (0.049
g of
magnesium/100 g of diet) but not the low magnesium diet. We speculate
that the
increased utilization of magnesium by feeding the calcium gluconate diet
to a
limited extent prevented the low magnesium status and the severity of
nephrocalcinosis caused by adding excess dietary phosphorus and calcium.
PMID 8906632
76: Am J Clin Nutr. 1996 Jul;64(1):717.
A followup study on the effects of calciumsupplement withdrawal and puberty
on
bone acquisition of children.
Lee WT, Leung SS, Leung DM, Cheng JC.
Recent calcium supplementation trials in children have confirmed a positive
but
moderate effect of calcium intake on bone mineral accretion. However,
the
lasting effect of a higher bone mineral mass after calciumsupplement withdrawal
is not known. This is an 18mo followup study conducted after an 18mo
controlled calcium supplementation trial to study the persistent effect
of
higher bone mineral mass in children. Radial bone mineral mass was determined
by
singlephoton absorptiometry; lumbar spine and femoral neck bone mineral
mass
were evaluated by dualenergy Xray absorptiometry in 84 healthy Hong Kong
children at age 8.5 y and these evaluations were repeated at age 10 y.
Pubertal
status was determined by Tanner staging. At the end of the followup, the
differences in percentage gains in lumbar spine bone mineral content (12.1
+/
8.2% compared with 14.9 +/ 10.05%, P = 0.24) and lumbar spine area (8.6
+/
5.1% compared with 9.4 +/ 5.5%, P = 0.47) between the study and control
groups
disappeared. Dietary calcium intakes during followup were similar for
the two
groups (555 and 640 mg/d, P = 0.23). In multipleregression analyses, pubertal
status was the strongest correlate of bone acquisition and linear growth
in the
study period. In conclusion, higher percentage gains in bone mineral mass
in
childhood by calcium supplementation for 18 mo were reversible. Our study
showed
that the benefits of calcium supplementation disappear after treatment
is
withdrawn. Longerterm calcium trials are necessary to determine whether
peak
bone mass can be modified through sustained supplementation so that appropriate
calcium intakes can be determined.
PMID 8669418
77: J Rheumatol. 1996 Jun;23(6):9951000.
Vitamin D and calcium in the prevention of corticosteroid induced osteoporosis:
a
3 year followup.
Adachi JD, Bensen WG, Bianchi F, Cividino A, Pillersdorf S, Sebaldt RJ,
Tugwell
P, Gordon M, Steele M, Webber C, Goldsmith CH.
OBJECTIVE: To determine the efficacy and safety of vitamin D 50,000 units/week
and calcium 1,000 mg/day in the prevention of corticosteroid induced
osteoporosis. METHODS: A minimized double blind, placebo controlled trial
in
corticosteroid treated subjects in a tertiary care university affiliated
hospital. The sample was 62 subjects with polymyalgia rheumatica, temporal
arteritis, asthma, vasculitis, or systemic lupus erythematosus. The primary
outcome measure was the percentage change in bone mineral density (BMD)
of the
lumbar spine in the 2 treatment groups from baseline to 36 mo followup.
RESULTS:
BMD of the lumbar spine in the vitamin D and calcium treated group decreased
by
a mean (SD) of 2.6% (4.1%) at 12 mo, 3.7% (4.5%) at 24 mo, and 2.2% (5.8%)
at 36
mo. In the placebo group there was a decrease of 4.1% (4.1%) at 12 mo,
3.8%
(5.6%) at 24 mo, and 1.5% (8.8%) at 36 mo. The observed differences between
groups were not statistically significant. The difference at 36 mo was0.693%
(95% CI 5.34, 3.95). CONCLUSION: Vitamin D and calcium may help prevent
the
early loss of bone seen in the lumbar spine as measured by densitometry
of the
lumbar spine. Longterm vitamin D and calcium in those undergoing extended
therapy with corticosteroids does not appear to be beneficial.
78: J Clin Endocrinol Metab. 1996 May;81(5):1699703.
Role of calcium intake in modulating agerelated increases in parathyroid
function and bone resorption.
McKane WR, Khosla S, Egan KS, Robins SP, Burritt MF, Riggs BL.
Serum parathyroid hormone (PTH) and bone resorption increase in elderly
women
and contribute to agerelated bone loss. Whether these abnormalities are
caused
by calcium deficiency resulting from agerelated decreases in absorption
and
renal conservation is unclear. We studied 28 normal elderly women (mean
+/ SD,
age 69.3 +/ 2.7 yr) who were maintained for 3 yr on usual calcium intake
levels
(20.4 +/ 7.2 mmol/day [815 +/ 289 mg/day]; n = 15) (known as the usual
calcium
group) or high calcium intake levels (60.4 +/ 6.5 mmol/day [2414+/260
mg/day];
n = 13) (known as the high calcium group) and a reference group of 12
normal
young adult women (age 30.1 +/ 4.4 yr), whose calcium intake was 23.0
+/ 4.8
mmol/day (918 +/ 193 mg/day) (known as the young group). Serum PTH was
measured
every 2 h, and urinary excretion of deoxypyridinoline (Dpd), a new marker
for
bone resorption, was measured in 4 h collections. Parathyroid gland secretory
capacity was assessed during induced hypocalcemia. The mean 24 h serum
PTH was
40% lower (P < 0.001), and the mean 24 h urinary Dpd was 35% lower
(P < 0.005)
in the high than in the usual calcium group. Mean parathyroid gland secretory
capacity also was 47% lower (P < 0.005) in the high calcium group than
in the
usual calcium group. However, the usual calcium group had a mean 24 h
serum PTH
level that was 70% higher (P < 0.001) and a mean 24 h urinary Dpd level
that was
30% higher (P < 0.005) than the young group, whereas the high calcium
group was
indistinguishable from the young group. Thus, failure of elderly women
to
increase their calcium intake to offset agerelated increases in calcium
requirement contributes substantially to their development of increased
parathyroid activity and increased bone resorption, whereas a high calcium
intake can reverse both abnormalities.
79: Maturitas. 1996 Apr;23(3):32732.
Prophylaxis of osteoporosis with calcium, estrogens and/or eelcatonin:
comparative longitudinal study of bone mass.
PerezJaraiz MD, Revilla M, Alvarez de los Heros JI, Villa LF, Rico H.
OBJECTIVE: To evaluate three different therapeutic regimens for the prevention
of osteoporosis in natural and surgical postmenopausal women who had been
found
to have rapid bone loss in analytical studies. METHODS: A total of 104
naturally
or surgically postmenopausal women were studied, and subsequently followedup
during 1 year for avoidance of the influence of seasonal variation on
bone mass,
a factor overlooked in several studies. They were randomized into four
groups of
26 patients each: the untreated control group (mean age 50 +/ 5 years);
the
hormonal replacement treatment (HRT) group (mean age 48 +/ 6 years), which
was
treated for 24 days each month with transdermal 17 betaestradiol, 50 mg/day,
together with medroxiprogesterone, 10 mg during 12 days; the calcium group
(mean
age 50 +/ 4 years), which was treated with elemental calcium, 1 g/day;
and the
calcitonin group (mean age 50 +/ 5 years), which was treated for 10 days
each
month with eel calcitonin, 40 IU/day and with elemental calcium, 500 mg/day.
Fullbody bone densitometry, for measuring total body bone mineral content
(TBBMC), was carried out in all the women at baseline and 1 year. TBBMC
was
corrected for body weight by dividing its value by body weight (TBBMC/W).
RESULTS: After 1 year TBBMC/W was lower in every group: 2.14% (P <
0.001) in
the control group; 0.14% (P = NS) in the HRT group (P < 0.05 vs. controls);
0.18% (P = NS) in the calcium group (P < 0.05 vs. controls); and 0.06%
(P =
NS) in the calcitonin group (P < 0.01 vs. controls; P < 0.05 vs.
calcium and
HRT). CONCLUSIONS: These findings show that all three treatments are effective
in the prevention of postmenopausal loss of bone mass.
80: Am J Clin Nutr. 1996 Mar;63(3):3547.
Bioavailability of calcium supplements and the effect of Vitamin D: comparisons
between milk, calcium carbonate, and calcium carbonate plus vitamin D.
Mortensen L, Charles P.
Our aim was to examine a regimen for calcium supplementation because
various
factors seem to be important for its bioavailability, and to examine the
effect
of adding vitamin D to the supplement. The participants were 20 healthy
women
aged 2859 y (chi: 38 y). During the 3d periods and 1 d before, the
participants were consuming a calcium and energybalanced diet as similar
to
their usual daily diet as possible. The study was designed as a randomized,
placebocontrolled, partly blinded crossover study divided into four periods
of
3 d each: 1) three tablets containing 1000 mg CaCO3/d, 2) three tablets
containing 1000 mg CaCO3 plus 5 micrograms (200 IU) vitamin D/d, 3)1 L
more milk
than in the usual daily diet, and 4) three placebo tablets daily.
Bioavailability of the different calciumsupplement regimens were evaluated
by
changes in 24h urinary excretion of calcium, phosphate, and magnesium.
A
significant increase in urinary calcium excretion was found during all
periods
of supplementation compared with the placebo period (P<0.01). Excretion
of
calcium in the calcium carbonate period was not significantly higher that
that
in the milk period, but calcium carbonate plus vitamin D resulted in
significantly higher calcium excretion compared with that in the milk
period. We
conclude that the examined calcium carbonate regimen is at least as good
a
calcium supplement as milk, and that addition of 600 IU vitamin D/d promptly
resulted in an increase in urinary calcium excretion after an increase
in
calcium absorption, even in healthy women.
81: Hepatogastroenterology. 1996 JanFeb;43(7):1524.
Calcium chemoprevention in colorectal cancer.
Duris I, Hruby D, Pekarkova B, Huorka M, Cernakova E, Bezayova T, Ondrejka
P.
BACKGROUND/AIMS: There are genetic, endoengenous, and exogenous factors
responsible for colorectal cancer. Calcium may play a chemopreventive
role in
high risk groups. Binding fatty and biliary acids and their reduced absorbtion,
with a consequent decrease of proliferative stimulation and reduction
of
secondary carcinogenic compounds, may explain this role. MATERIAL AND
METHODS: 175 patients with adenomatous polyps after polypectomy and with
calcium
chemoprevention were evaluated for polyps recurrence. Another three groups
of
patients with colorectal cancer without chemoprevention (A,B) and with
chemoprevention (group C) were followed concerning survival after surgery.
RESULTS: The cumulative survival rate of patients after surgery due to
colorectal carcinoma is significantly higher in a calcium chemopreventive
group.
Adenomatous polyps recurrences after polypectomy are lower (12.9%) in
the
chemoprevention group than in the group without prevention (55%) with
a mean
time of followup 3.1 yrs. CONCLUSIONS: Calcium is an important chemopreventive
agent in adenomatous polyps after polypectomy and after colorectal surgery
for
colorectal cancer.
82: Osteoporos Int. 1996;6(4):3149.
The effect of a short course of calcium and vitamin D on bone turnover
in older
women.
Prestwood KM, Pannullo AM, Kenny AM, Pilbeam CC, Raisz LG.
Calcium and vitamin D (1200 mg/day + 800 IU) has been shown to reduce
hip
fracture incidence in older women living in longterm care facilities who
had
borderline low vitamin D levels. We examined the effect of a short course
of
calcium and vitamin D on biochemical markers of bone turnover in older
communityliving women. Twelve communityliving women (mean age 75 years)
in
good general health, without diseases or on medications known to affect
bone,
were entered into the study. All women were treated with calcium citrate
(1500
mg/day of elemental calcium) and vitamin D3 (1000 IU/day) (Ca + D) for
6 weeks.
Biochemical markers of bone turnover were measured in serum and urine
collected
at baseline (two samples), 5 and 6 weeks on Ca + D, and 5 and 6 weeks
after
termination of Ca + D. Markers of bone formation were osteocalcin, bone
alkaline
phosphatase and type I procollagen peptide. Markers of bone resorption
were
urinary hydroxyproline, free pyridinoline and deoxypyridinoline crosslinks,
and
Ntelopeptides of type I collagen. Parathyroid hormone (PTH) and
25hydroxyvitamin D were also measured at baseline, 6 weeks on treatment
and 6
weeks after termination of treatment. All markers of bone resorption decreased
on Ca + D and returned to baseline after termination of Ca + D (p <
0.05).
Markers of bone formation did not change with Ca + D treatment. PTH decreased
on
Ca + D and returned to baseline after treatment, and 25hydroxyvitamin
D
increased with treatment and remained elevated 6 weeks after the end of
treatment. We conclude that Ca + D reduces bone resorption in older women,
possibly by suppressing PTH levels.
83: Scand J Rheumatol Suppl. 1996;103:758; discussion 7980.
Prevention of hip fractures by correcting calcium and vitamin D insufficiencies
in elderly people.
Meunier P.
For a 50year old caucasian woman today, the risk of a hip fracture over
her
remaining lifetime is about 17%. Tomorrow the situation will clearly be
worse
because the continual increase in life expectancy will cause a 3fold rise
in
worldwide fracture incidence over the next 60 years, particularly in women,
but
also in men. In addition, a secular increase in the incidence of hip fractures
in individuals of the same age has been noted in both sexes by several
investigators, and the cost of hip fractures is expected to dramatically
increase in the next decades. Consequently, preventive strategies are
urgently
required. A great deal has been learned in recent years about the risk
factors
for hip fracture, the pathophysiology of this fracture, and the prediction
of
fracture risk, particularly through bone mass measurements on the hip
and
biochemical evaluations of parathyroid and vitamin D status. The two main
determinants of hip fractures are falls and bone loss leading to an intrinsic
femoral fragility. A substantial femoral bone loss continues throughout
the old
age, with a continuous and exponential increase in the risk of hip fracture,
and
any reduction or arrest of this loss will induce an important reduction
in the
incidence of hip fractures. A preventive effect on the risk of hip fracture
may
be partly achieved by using long term estrogen replacement therapy after
menopause, but also by using vitamin D and calcium supplements for a late
prevention in elderly people. Vitamin D insufficiency and deficit in calcium
intake are very common in elderly people living either in institutions
or at
home, particularly in Europe where dairy products are not fortified with
vitamin
D. The cumulative response to this deficit in calcium intake and low vitamin
D
status is a negative calcium balance which stimulates parathyroid hormone
secretion. In 300 residents of nursing homes, we recently found a significant
negative correlation between serum 25 OHD and log serum PTH after
ageadjustment. In addition, in 446 elderly women living at home in 5 French
cities and selected from the voting lists, we also found an ageadjusted
relationship between serum 25 OHD and PTH concentrations. This senile
secondary
hyperparathyroidism is one of the determinants of femoral bone loss and
can be
reversed by calcium and vitamin D supplements. We have shown in a 3year
controlled prospective study that the daily use of these supplements (1.2
g of
calcium and 800 IU of vitamin D3) given in a large population of 3270
elderly
ambulatory women living in nursing homes reduced of 23% (intentiontotreat
analysis) the number of hip fractures and other non vertebral fractures.
In
parallel, serum perathyroid hormone concentration was reduced of 28% and
low
serum 25hydroxyvitamin D concentration returned to normal values. After
18
months of treatment the bone density of the total proximal femoral region
had
increased 2.7% the vitamin D3calcium group and decreased 4.6% in the placebo
group (p < 0.001). This prevention is safe and can be recommended in
people
living in institutions. It could be also useful in other elderly subjects
particularly at risk because of a low calcium intake, an absence of solar
exposure and a previous history of falls. From the data of our study we
assessed
the economic consequences in terms of medical cost of this prevention.
In case
of treatment of all women living in nursing homes in France, this would
saved FF
150000000 per year, the economic balance of prevention becoming positive
as soon
as the age of the beginning of the prevention reaches 73.5 years. It is
now
possible to partly stop bone loss in elderly people and it is never too
late to
prevent hip fractures with calcium and vitamin D supplements.
84: Nutrition. 1995 SepOct;11(5):40917.
Optimal calcium intake. Sponsored by National Institutes of Health Continuing
Medical Education.
[No authors listed]
The National Institutes of Health Consensus Development Conference on
Optimal
Calcium Intake brought together experts from many different fields including
osteoporosis and bone and dental health, nursing, dietetics, epidemiology,
endocrinology, gastroenterology, nephrology, rheumatology, oncology,
hypertension, nutrition and public education, and biostatistics, as well
as the
public, to address the following questions: 1) What is the optimal amount
of
calcium intake? 2) What are the important cofactors for achieving optimal
calcium intake? 3) What are the risks associated with increased levels
of
calcium intake? 4) What are the best ways to attain optimal calcium intake?
5)
What public health strategies are available and needed to implement optimal
calcium intake recommendations? and 6) What are the recommendations for
future
research on calcium intake? The consensus panel concluded that: A large
percentage of Americans fail to meet currently recommended guidelines
for
optimal calcium intake. On the basis of the most current information available,
optimal calcium intake is estimated to be 400 mg/day (birth6 months) to
600
mg/day (612 months) in infants; 800 mg/day in young children (15 years)
and
8001,200 mg/day for older children (610 years); 1,2001,500 mg/day for
adolescents and young adults (1124 years); 1,000 mg/day for women between
25
and 50 years; 1,2001,500 mg/day for pregnant or lactating women; and 1,000
mg/day for postmenopausal women on estrogen replacement therapy and 1,500
mg/day
for postmenopausal women not on estrogen therapy. Recommended daily intake
for
men is 1,000 mg/day (2565 years). For all women and men over 65, daily
intake
is recommended to be 1,500 mg/day, although further research is needed
for this
age group. These guidelines are based on calcium from the diet plus any
calcium
taken in supplemental form. Adequate vitamin D is essential for optimal
calcium
absorption. Dietary constituents, hormones, drugs, age, and genetic factors
influence the amount of calcium required for optimal skeletal health.
Calcium
intake, up to a total intake of 2,000 mg/day, appears to be safe in most
individuals. The preferred source of calcium is through calciumrich foods
such
as dairy products. Calciumfortified foods and calcium supplements are
other
means by which optimal calcium intake can be reached in those who cannot
meet
this need by ingesting conventional foods. A unified public health strategy
is
needed to ensure optimal calcium intake in the American population.
PMID 8748190
85: Med Hypotheses. 1995 Jul;45(1):6872.
Calcium supplementation prevents pregnancyinduced hypertension by increasing
the production of vascular nitric oxide.
LopezJaramillo P, Teran E, Moncada S.
Pregnancyinduced hypertension (PIH) remains a common cause of maternal
and
fetal morbidity and mortality. During the past 7 years, some progress
has been
made in the prevention of PIH. Specifically, clinical studies have shown
that
supplementation with calcium can significantly reduce the frequency of
PIH,
specially in populations with a low calcium intake. We have suggested
that, in
such a population, calcium supplementation is a safe and effective measure
for
reducing the frequency of PIH. Thus, the purpose of this article is to
advance a
hypothesis about the mechanism by which calcium supplementation reduces
the risk
of PIH. We propose that dietary calcium supplementation reduces the frequency
of
PIH by maintaining the serum ionized calcium level which is crucial for
the
production of endothelial nitric oxide, the increased generation of which
maintains the vasodilatation that is characteristic of normal pregnancy.
86: Am J Med. 1995 Apr;98(4):3315.
Longterm effects of calcium supplementation on bone loss and fractures
in
postmenopausal women: a randomized controlled trial.
Reid IR, Ames RW, Evans MC, Gamble GD, Sharpe SJ.
PURPOSE: To determine the longterm effects of calcium supplements or
placebo on
bone density in healthy women at least 3 years postmenopause. PATIENTS
AND
METHODS: Eightysix women from our previously reported 2year study agreed
to
continue on their doubleblind treatment allocation (1 g elemental calcium
or
placebo) for a further 2 years, with 78 women (40 on placebo) reaching
the
4year end point. Median (interquartile range) dietary calcium intakes
for the
whole group were 700 mg (range 540 to 910) per day at baseline, 670 mg
(range
480 to 890) per day at 2 years, and 640 mg (range 460 to 880) per day
at 4
years. The bone mineral density (BMD) of the total body, lumbar spine,
and
proximal femur was measured every 6 months by dualenergy, xray absorptiometry.
RESULTS: There was a sustained reduction in the rate of loss of total
body BMD
in the calcium group throughout the 4year study period (P = 0.002), and
bone
loss was significantly less in the calciumtreated subjects in years 2
through 4
also (difference between groups 0.25% +/ 0.11% per year, P = 0.02). In
the
lumbar spine, bone loss was reduced in the calcium group in year 1 (P
= 0.004),
but not subsequently. There was, however, a significant treatment effect
at this
site over the whole 4year period (P = 0.03). In the proximal femur, the
benefit
from calcium treatment also tended to be greater in the first year and
was
significant over the 4year study period in the femoral neck (P = 0.03)
and the
trochanter (P = 0.01). Nine symptomatic fractures occurred in 7 subjects
in the
placebo group and 2 fractures in 2 subjects receiving calcium (P = 0.037).
CONCLUSIONS: Calcium supplementation produces a sustained reduction in
the rate
of loss of total body BMD in healthy postmenopausal women.
87: J Pediatr. 1995 Apr;126(4):5516.
Effects of dairy products on bone and body composition in pubertal girls.
Chan GM, Hoffman K, McMurry M.
OBJECTIVE: To study the effect of calcium supplementation with dairy
products on
the bone and body composition of pubertal girls. DESIGN: Randomized control
study with 12month followup. SETTING: General community. SUBJECTS: Fortyeight
white girls whose mean age was 11 years and sexual development at Tanner
stage
2. INTERVENTION: One group's diet was supplemented with dairy products
to the
recommended dietary allowance of 1200 mg calcium daily. The other group
ate
their usual diet. MAIN OUTCOME MEASURES: Bone mineral content and density
were measured at the radius, femoral neck, lumbar spine, and total body
bone mineral
by singlephoton and dualenergy xray absorptiometry at the start of the
study
and after 3, 6, 9, and 12 months. Body composition (lean body mass and
body fat)
was measured by dualenergy xray absorptiometry at the same intervals.
Serum
calcium, phosphate, 25hydroxyvitamin D, 1,25dihydroxyvitamin D, alkaline
phosphatase, magnesium, and albumin concentrations were determined at
the start
and end of the study. The urinary calcium/creatinine ratio and hydroxyproline
concentration were also determined. RESULTS: The dairy group had higher
intakes
of calcium, phosphate, vitamin D, and protein than control subjects. The
dairy
group had significantly greater increases during the 1year study in bone
mineral density at the lumbar spine bones (22.8% +/ 6.9% vs 12.9% +/ 8.3%)
and
in total body bone mineral (14.2% +/ 7.0% vs 7.6% +/ 6.0%) than control
subjects. Dietary calcium, phosphate, vitamin D, and protein intakes were
associated with the lumbar bone density and total body bone calcium. There
were
no differences in serum or urinary biochemical values between the two
groups at
the start or end of the study. CONCLUSIONS: Young girls whose dietary
calcium
intake was provided primarily by dairy products at or above the recommended
dietary allowances had an increased rate of bone mineralization. Increased
intake of dairy foods did not increase overall total or saturated fat
intake and
was not associated with excessive weight gain or increased body fat.
88: Chin Med J (Engl). 1995 Jan;108(1):579.
Calcium supplementation during pregnancy for reducing pregnancy induced
hypertension.
Cong K, Chi S, Liu G.
Pregnancy induced hypertension (PIH) is a common complication in pregnancy
and
prenatal stage. Because the direct and indirect relationship between low
calcium
intake and many diseases, such as rachitis, young age myopia and hypertension,
calcium supplementation has been a hot topic among nutritionists. Randomized
trials of calcium supplementation during pregnancy were conducted in 212
healthy
primipara. They were divided into 4 groups and gave 120mg, 240mg, 1g or
2g of
calcium daily from 20 to 28 wks of gestation up to delivery respectively.
As a
result, the incidence of PIH was 8.9%, 7.5%, 8% and 4% respectively in
these
groups. The control group (106 pregnant women) who did not receive calcium
gave
an incidence of 18%. Supplementation of 2g of calcium daily showed significant
results in lowering the incidence of PIH (P < 0.05) without any adverse
effects.
In 1992 calcium supplementation was widely used in antenatalclinic. 200
cases
with intake of 2g calcium were compared with corresponding noncalcium
supplementation cases, and the incidence of PIH was 7.5% and 16.5% (P
< 0.005)
respectively. Mediating parathyroid hormone and renin activity are thought
to be
the effect of calcium on decreasing the incidence of PIH.
89: J Cell Biochem Suppl. 1995;22:6573.
Calcium and the prevention of colon cancer.
Lipkin M, Newmark H.
Chemoprevention studies utilizing calcium have now progressed from basic
measurements to clinical trials. Calcium's effects on epithelial cells
have
demonstrated decreased proliferation and induced cell differentiation
with
increasing levels of calcium in vitro, similar in vivo effects in rodent
and
human colon, and decreased carcinogeninduced colonic tumor formation in
rodents. Current studies are attempting to inhibit colonic adenoma formation
in
human subjects. Most but not all epidemiologic studies also link increased
dietary calcium with a decreased risk of colon cancer. In animal models,
supplemental dietary calcium has decreased mammary epithelial cell hyperplasia
and hyperproliferation and colonic cell hyperproliferation when the latter
was
induced by bile acids, fatty acids, and partial resection of the small
intestine. Supplemental dietary calcium also decreased carcinogeninduced
colonic tumors in several rodent models. In normal mice, and in mice carrying
a
targeted apc gene mutation, we recently increased colonic polypoid hyperplasias
by a Westernstyle diet containing low calcium and vitamin D. In human
subjects
at increased risk for colon cancer, oral calcium supplementation significantly
reduced colonic epithelial cell proliferation in most of the studies,
including
four randomized clinical trials. These studies have now progressed to
shortterm
human clinical trials, including trials that measure the regrowth of transformed
adenoma cells. Shortterm adenomaregrowth clinical trials, however, are
limited
in their ability to measure whether chemopreventive agents inhibit early
genotoxic events, abnormal cellular metabolic activities involved in tumor
promotion over many years, or the progression of adenoma cells to carcinoma.
90: Miner Electrolyte Metab. 1995;21(13):23641.
Calcium, why and how much?
Palmieri GM.
Although calcium (Ca) is pivotal for the prevention of osteoporosis,
its role in
the prevention of other unrelated diseases such as arterial hypertension,
cancer
of the colon and nephrolithiasis is perplexing. No unitarian hypothesis
explaining these unrelated effects of Ca has been postulated. Cytosolic
Ca
concentration is 10,000fold lower than in the extracellular space, and
this
gradient is tightly maintained. Abnormal elevation of cytosolic Ca causes
cell
damage and death. Parathyroid hormone is a Ca agonist and the suppression
of its
secretion by Ca could explain the beneficial role of Ca intake in multiple
diseases. Thus, parathyroid ablation improves hypertension in rats and
cardiomyopathy in hamsters. Since anthropologic data suggests a higher
Ca
intake, of approximately 1,600 1,600 mg/day, in preneolithic than in modern
diets, it is likely that our levels of PTH on genetically predisposed
subjects
with a loose cellular Ca control may aggravate frequent modern diseases
and the
process of aging. A higher Ca intake in both sexes should be one of the
goals of
preventive medicine of our time.
91: Headache. 1994 NovDec;34(10):5902.
Alleviation of migraines with therapeutic vitamin D and calcium.
ThysJacobs S.
Two postmenopausal migraineurs who developed frequent and excruciating
migraine
headaches (one following estrogen replacement therapy and the other following
a
stroke) were treated with combination vitamin D and calcium. Therapeutic
replacement with vitamin D and calcium resulted in a dramatic reduction
in the
frequency and duration of their migraine headaches.
PMID 7843955
92: Int J Gynaecol Obstet. 1994 Nov;47(2):11520.
Prevention of preeclampsia with calcium supplementation and vitamin D3
in an
antenatal protocol.
Ito M, Koyama H, Ohshige A, Maeda T, Yoshimura T, Okamura H.
OBJECTIVES: Using an angiotensin sensitivity test we carried out a prospective
study in an attempt to predict the possible onset of preeclampsia and
to prevent
it by calcium supplementation (elemental calcium 156 or 312 mg/day per
os) and
treatment with vitamin D3 (0.5 micrograms/3 day per os). METHOD: We used
a study
design in which 666 singleton pregnant women were managed with conventional
antenatal care and 210 singleton pregnant women were managed with a protocol,
together with conventional antenatal care. RESULT: Of the 666 women managed
conventionally, 113 (16.9%) developed preeclampsia. However, the incidence
of
preeclampsia in the 210 women managed on the protocol was lower, at 10.9%.
CONCLUSION: Our findings indicate that this protocol for the prediction
and
prevention of preeclampsia is useful for pregnant women at high risk of
developing preeclampsia.
93: Headache. 1994 Oct;34(9):5446.
Vitamin D and calcium in menstrual migraine.
ThysJacobs S.
Two premenopausal women with a history of menstruallyrelated migraines
and
premenstrual syndrome were treated with a combination of vitamin D and
elemental
calcium for late luteal phase symptoms. Both cited a major reduction in
their
headache attacks as well as premenstrual symptomatology within 2 months
of
therapy. These observations suggest that vitamin D and calcium therapy
should be
considered in the treatment of migraine headaches.
PMID 8002332
94: J Paediatr Child Health. 1994 Oct;30(5):4446.
Oral calcium treatment in vitamin Ddependent rickets type II.
Wong GW, Leung SS, Law WY, Cheung NK, Oppenheimer SJ.
Vitamin Ddependent rickets type II is a rare hereditary disease that
results
from target organ resistance to the action of 1,25dihydroxyvitamin D3.
There is
a great heterogeneity in the clinical presentation of this condition.
The
affected patients usually present early in childhood with clinical and
biochemical evidence of rickets. Physiological replacement dosage of
1,25dihydroxyvitamin D3 has no therapeutic effect. Responses to pharmacological
doses of vitamin D metabolites or longterm calcium infusion have been
variable.
A case is reported here of an 8 year old girl, of consanguineous parents
with
vitamin Ddependent rickets, type II, in whom treatment with high dose
oral
calcium resulted in marked biochemical and radiological improvement. It
is
concluded that high dose oral calcium treatment is an effective treatment
option
for patients with vitamin Ddependent rickets type II.
PMID 7833085
95: J Clin Endocrinol Metab. 1994 Sep;79(3):7305.
The effect of calcium supplementation on the circadian rhythm of bone
resorption.
Blumsohn A, Herrington K, Hannon RA, Shao P, Eyre DR, Eastell R.
Bone resorption shows a circadian rhythm in human subjects, but the
physiological mechanisms underlying this rhythm are unknown. We compared
the
circadian rhythm of bone collagen degradation in 18 premenopausal women
before
and after oral calcium supplementation (1000 mg calcium for 14 days).
Subjects
were randomized to receive calcium at either 0800 h or 2300 h. Continuous
48h
urine collections and 1 day of 4h urine collections were obtained before
and
after the 14day supplementation period. We measured urinary deoxypyridinoline
(Dpd) and the crosslinked Ntelopeptide of type I collagen (NTx) as biochemical
markers of bone resorption. There was a significant effect of time of
day on
excretion of Dpd and NTx (analysis of variance, P < 0.001) with peak
excretion
between 03000700 h and a nadir between 15001900 h. The mean amplitude
(peak to
trough) was similar for Dpd and NTx (70.3% and 63.3%, respectively). Evening
calcium supplementation resulted in marked suppression of the nocturnal
increase
in Dpd and NTx and reversed the usual nocturnal increase in the level
of
parathyroid hormone. In contrast, morning calcium supplementation had
no
significant effect on the circadian rhythm of Dpd or NTx. Evening calcium
supplementation suppressed overall daily excretion of Dpd by 20.1% (P
= 0.03)
and NTx by 18.1% (P = 0.03). Morning calcium supplementation had no significant
effect on overall daily excretion of either Dpd or NTx. We conclude that
evening
calcium supplementation suppresses the circadian rhythm of bone resorption.
The
daily rhythm of PTH secretion or calcium intake is likely to be an important
determinant of this rhythm. Experimental protocols designed to investigate
the
effect of calcium supplementation on bone mineral density should take
the timing
of supplementation into account.
96: Obstet Gynecol. 1994 Sep;84(3):34953.
Prevention of pregnancyinduced hypertension by calcium supplementation
in
angiotensin IIsensitive patients.
SanchezRamos L, Briones DK, Kaunitz AM, Delvalle GO, Gaudier FL, Walker
CD.
OBJECTIVE: To evaluate the efficacy of oral supplemental calcium in reducing
the
incidence of pregnancyinduced hypertension (gestational hypertension or
preeclampsia) in angiotensinsensitive nulliparas. METHODS: Sensitivity
to
intravenously infused angiotensin was determined at 2428 weeks' gestation
in
281 nulliparous women who had positive rollover tests. Angiotensinsensitive
women were given 2 g/day of oral elemental calcium or placebo in a randomized,
doubleblind clinical trial. The tablets were dispensed by the hospital
pharmacy
in serially numbered computerized pill bottles so as to assess compliance.
Repeat angiotensin sensitivity test was performed at 3436 weeks' gestation.
RESULTS: Sixtythree of 67 angiotensinsensitive nulliparas were evaluable;
29
received calcium and 34 received placebo tablets. Four of 29 calciumtreated
subjects (13.8%, 95% confidence interval [CI] 432%) developed preeclampsia,
compared to 15 of 34 (44.1%, 95% CI 2762%) in the placebo group (relative
risk
[RR] 0.37, 95% CI 0.150.92; P = .01). The incidence of any type of hypertension
was nine of 29 (31%, 95% CI 1551%) with calcium treatment, compared to
22 of 34
(64.7%, 95% CI 4680%) with placebo (RR 0.46, 95% CI 0.250.86; P = .01).
CONCLUSION: Calcium supplementation given in pregnancy to highrisk nulliparas
reduces the incidence of pregnancyinduced hypertension.
97: Osteoporos Int. 1994 Sep;4(5):24552.
Effects of calcium supplements on femoral bone mineral density and vertebral
fracture rate in vitaminDreplete elderly patients.
Chevalley T, Rizzoli R, Nydegger V, Slosman D, Rapin CH, Michel JP, Vasey
H,
Bonjour JP.
The efficacy of calcium (Ca) in reducing bone loss is debated. In a randomized
placebocontrolled doublemasked study, we investigated the effects of oral
Ca
supplements on femoral shaft (FS), femoral neck (FN) and lumbar spine
(LS) bone
mineral density (BMD), and on the incidence of vertebral fracture in
vitaminDreplete elderly. Ninetythree healthy subjects (72.1 +/ 0.6 years)
were randomly allocated to three groups receiving 800 mg/day Ca in two
different
forms or a placebo for 18 months. Sixtythree patients (78.4 +/ 1.0 years)
with
a recent hip fracture were allocated to two groups receiving the two forms
of Ca
without placebo. FS BMD changes in Casupplemented nonfractured women were
significantly different from those in the placebo group (+0.6 +/ 0.5%
v 1.2
+/ 0.7%, p < 0.05). There was no difference in effect between the two
forms of
Ca. The changes of +0.7 +/ 0.8% v 1.7 +/ 1.6% in FN BMD of Casupplemented
women and the placebo group did not reach statistical significance. In
fractured
patients, FS, FN and LS BMD changes were 1.3 +/ 0.8, +0.3 +/ 1.6 and +3.1
+/
1.2% (p < 0.05 for the last). The rate of new vertebral fractures was
74.3 and
106.2 fractures per 1000 patientyears in Casupplemented nonfractured subjects
and in the placebo group, respectively, and 144.0 in Casupplemented fractured
patients. Thus, oral Ca supplements prevented a femoral BMD decrease and
lowered
vertebral fracture rate in the elderly.
98: Am J Respir Crit Care Med. 1994 Aug;150(2):3947.
Therapy of steroidinduced bone loss in adult asthmatics with calcium,
vitamin
D, and a diphosphonate.
Worth H, Stammen D, Keck E.
In a prospective, controlled, and randomized clinical trial, we examined
the
effects of treatment with vitamin D (1,000 IU/d), calcium (1 g/d), and
ethane1hydroxy1,1diphosphonate (EHDP; 7.5 mg/kg body weight) on vertebral
bone mass in fourteen asthmatics undergoing longterm treatment with
systemically applied corticosteroids. The extent of steroidinduced bone
loss
was judged by vertebral bone density of the lumbar spine measured by dualphoton
absorptiometry as well as by vertebral crush fracture incidence examined
by
conventional Xray. Results of the measurements before treatment and after
six
mo were compared with those of an untreated control group of nineteen
asthmatics. Bone density increased during the observation period by 5%
in the
treated group, compared with a decrease of 4.3% in the untreated control
group
(p < 0.01). Moreover, in the treated group no radiologically visible
new
fractures occurred; in the control group new fractures were observed in
four
patients. There were no serious side effects of the applied drugs during
the
6mo period. Therefore, the combination of EHDP, calcium, and vitamin D
appears
to be a useful regimen for the management of steroidinduced bone loss
in adult
asthmatics.
99: J Dairy Sci. 1994 May;77(5):115560.
ADSA Foundation Lecture. Low calcium intake: the culprit in many chronic
diseases.
Heaney RP, BargerLux MJ.
Calcium is the fifth most abundant element in the earth's crust and is
necessary
for both plant and animal life today. Moreover, the natural diets of all
mammals
are rich in calcium. The diet of Stone Age human adults is estimated to
have
contained from 50 to 75 mmol of calcium (2000 to 3000 mg)/d, three to
five times
the median calcium intake of presentday US adults. Human physiology has
adapted
to this environmental abundance with an intestinal absorptive barrier
and
inefficient renal conservation of calcium. Although mammalian physiology
contains mechanisms by which organisms can adjust to temporary environmental
shortages, chronic calcium retention has a number of health consequences,
most
notably bone fragility, high blood pressure, and colon cancer. Evidence
indicates that improvement in calcium intake (or in vitamin D status)
prevents
some portion of each of these multifactorial problems. At least 14 intervention
studies have established the skeletal benefit of increased calcium intake
during
growth and among women in the late postmenopause. Other evidence suggests
that
adequate calcium may protect against saltsensitive and pregnancyassociated
hypertension and that high intakes of both dietary calcium and vitamin
D reduce
development of precancerous changes in colonic mucosa.
100: Clin Exp Pharmacol Physiol. 1994 Mar;21(3):1738.
Augmentation of baroreceptor reflex function by oral calcium supplementation
in
essential hypertension.
Dazai Y, Iwata T, Hiwada K.
1. We studied the effect of oral calcium supplementation (1.0 g/day)
for 1 week
on baroreceptor reflex function and the lability of blood pressure in
association with the changes in autonomic nervous activity in 14 hospitalized
patients with mild to moderate essential hypertension (nine males and
five
females, mean age of 56 +/ 11.2 (s.d.) years). 2. Baroreceptor reflex
sensitivity (BRS) was determined by the change in RR intervals in response
to
the pressor response induced by phenylephrine injection. We measured coefficient
of variation of RR interval (CVRR) and urinary excretion of catecholamines
to
evaluate the mechanism of change in BRS. We also used coefficient of variation
of blood pressure (CVBP) and error of single cosinor analysis as parameters
for
lability of 24h blood pressure. 3. The means of 24h systolic and diastolic
blood pressures showed no significant changes after calcium supplementation
for
1 week. BRS and CVRR were significantly increased by calcium supplementation.
Daily excretions of norepinephrine and epinephrine corrected by creatinine
were
unchanged. Both CVBP and error of 24h systolic blood pressure showed a
significant decrease after calcium treatment. 4. These results indicate
that
oral calcium supplementation augments baroreceptor reflex function, in
part
through an enhancement of parasympathetic nervous activity, resulting
in
reduction of the lability of blood pressure in patients with mild to moderate
essential hypertension.
101: J Rheumatol. 1994 Mar;21(3):5305.
Effects of nutritional supplementation on bone mineral status of children
with
rheumatic diseases receiving corticosteroid therapy.
Warady BD, Lindsley CB, Robinson FG, Lukert BP.
OBJECTIVE. Because children with rheumatic disease receiving longterm
corticosteroids are at high risk for developing osteoporosis, we attempted
to
determine whether nutritional supplementation would improve bone status
in this
group of children. METHODS. In a crossover design study, 10 corticosteroid
treated children with rheumatic disease and osteoporosis received calcium
and
vitamin D supplementation for 6 months to determine their effect on bone
density. They were then studied for 6 months without added nutrition
supplements. The mean age was 13.1 years with a mean duration of disease
of 4.2
years. Six patients had juvenile rheumatoid arthritis, 2 had systemic
lupus
erythematosus and 2 had mixed connective tissue disease. These children
obtained
a minimum of 1 g of calcium and 400 IU of vitamin D daily from diet and
added
supplements. Dual photon absorptiometry, laboratory and dietary data were
obtained at baseline, 6 months, and one year. RESULTS. Spinal bone density
significantly improved with supplementation. Osteocalcin values remained
low
throughout the study. CONCLUSION. Our results suggest some children with
rheumatic disease receiving corticosteroids would benefit from calcium
and
vitamin D supplementation.
PMID 8006898
102: Am J Hypertens. 1993 Nov;6(11 Pt 1):9337.
Augmentation of the renal tubular dopaminergic activity by oral calcium
supplementation in patients with essential hypertension.
Dazai Y, Iwata T, Hiwada K.
We studied the effect of oral calcium supplementation on renal tubular
dopaminergic activity in patients with mild to moderate essential hypertension.
Fifteen patients aged 45 to 68 years (nine men and six women, mean age
59 +/ 7
[SD]) participated in the study. We orally administered calcium (1.0 g
per day
for 1 week) during hospitalization. The change in 24h blood pressure (BP),
measured by ambulatory BP monitoring, and excretions of electrolytes and
catecholamines were investigated before and after 1 week of oral calcium
supplementation. The mean values of 24h systolic and diastolic BP showed
no
significant changes by calcium loading. Daily urinary excretion of free
dopamine, sodium clearance (CNa), fractional excretion of sodium (FENa),
and
urinary volume were significantly increased by oral calcium supplementation.
Urinary excretions of epinephrine and norepinephrine and creatinine clearance
showed no significant changes by oral calcium treatment. CNa and FENa
showed
significant correlations with urinary excretion of free dopamine. These
results
suggest that oral calcium supplementation induces natriuresis partly through
augmentation of renal tubular dopaminergic activity.
PMID 8305167
103: Calcif Tissue Int. 1993 Nov;53(5):3046.
Comparison of the suppressive effect of two doses (500 mg vs 1500 mg)
of oral
calcium on parathyroid hormone secretion and on urinary cyclic AMP.
Guillemant J, Guillemant S.
The respective effects of the ingestion of two different doses of calcium
(500
and 1500 mg) on serum ionized calcium, intact parathyroid hormone (PTH
184),
and the urinary excretion of 3',5'cyclic adenosine monophosphate (cyclic
AMP)
were evaluated in 15 young male adults. Ionized serum calcium and PTH
184 were
measured before and 1 hour, 2 hours and 3 hours (P1, P2, and P3) after
the oral
intake of calcium. Cyclic AMP was measured in 2hour urine samples collected
before and during 4 hours after the ingestion of calcium. Similar increments
in
serum ionized calcium (delta Ca2+) were observed except at P3 where the
delta
Ca2+ was significantly (P < 0.02) higher after 1500 mg (0.088 mmol/liter)
than
after 500 mg of (0.062 mmol/liter). In the same way, the comparison of
the PTH
184 concentrations showed no statistical difference except at P3 (P <
0.002).
When expressed as a percentage of P0, the P1 and P2 PTH 184 values were
more
suppressed after 1500 mg than after 500 mg of calcium (P1: 69% vs 59%;
P <
0.02; P2: 66% vs 50%; P < 0.02). However, the simultaneous cyclic AMP
responses (24% vs 19%) were not significantly different. The results show
that
the respective maximal effects on PTH secretion and on urinary cyclic
AMP of two
very different oral doses of calcium are only slightly different.
104: Zhonghua Fu Chan Ke Za Zhi. 1993 Nov;28(11):6579, 700.
[Calcium and pregnancy induced hypertension]
Cong KJ.
In this paper the relationship between calcium and pregnancy induced
hypertension (PIH) was prospectively studied. 150 normal pregnant women
were
divided into 3 groups: group A with supplement of calcium element 1g/day,
group
B 2g/day and group C with no calcium supplement. 8%, 4% and 18% of each
group
had developed PIH respectively. It seems that supplement of 2 gram calcium
per
day gave the best result. Furthermore the study was expanded: 200 cases
with
supplement of calcium element 2 g/day from 2028th week of pregnancy, another
200 pregnant women without calcium supplement. The occurrence of PIH was
7.5%
and 16.5% respectively. There was no adverse effect with 2 g calcium supplement.
The metabolism of calcium in normal pregnancy and PIH was discussed. Supplement
of calcium during pregnancy may benefit by reduction of PIH incidence.
105: J Thorac Cardiovasc Surg. 1993 Sep;106(3):5119.
Duration of asystolic reperfusion and reperfusate electrolyte composition
influence postcardioplegia ventricular fibrillation.
Holman WL, Spruell RD, Pacifico AD.
The conditions of postcardioplegia reperfusion that influence cardiac
electrophysiologic recovery have not yet been fully elucidated. Studies
of
postcardioplegia electrophysiologic recovery and reperfusioninduced
arrhythmias, particularly reperfusioninduced ventricular fibrillation,
are
useful for improving our understanding of reperfusion injury since
reperfusioninduced arrhythmias are sensitive indicators for reperfusion
injury.
The purpose of this study was to determine the effects of asystolic reperfusion
and reperfusate electrolyte composition on postcardioplegia electrophysiologic
recovery of the heart. The hypothesis tested is that the duration of asystolic
reperfusion produced by a hyperkalemic reperfusate is a primary determinant
for
the return of cardiac electrical activity without reperfusioninduced
ventricular fibrillation and that reperfusion with a hypocalcemichyperkalemic
solution further reduces the prevalence of reperfusioninduced ventricular
fibrillation by limiting myocyte calcium exposure during initial postischemic
recovery. Fiftysix pigs were supported by cardiopulmonary bypass and subjected
to identical conditions of hypothermic cardioplegic arrest. Reperfusion
was
initiated with unmodified pump blood, a hypocalcemicnormokalemic cardioplegic
solution, a hyperkalemicnormocalcemic cardioplegic solution, or a
hyperkalemichypocalcemic cardioplegic solution. The hyperkalemicnormocalcemic
solution was administered at a dose of 500 ml/m2 or 1500 ml/m2. The
hyperkalemichypocalcemic and hypocalcemicnormokalemic solutions were given
only at a dose of 500 ml/m2. All cardioplegic reperfusion solutions were
followed by infusion of unmodified pump blood for the remainder of the
15minute
period of controlled reperfusion. Reperfusioninduced ventricular fibrillation
was less prevalent in the highdose hyperkalemic solution group (4/12)
than in
the lowdose hyperkalemic solution (9/10) or unmodified pump blood (12/12)
groups (p < 0.05). The transmyocardial lactate gradient at the time
of initial
postreperfusion electrical activity was positive (0.21 +/ 0.04 mmol/L)
in the
highdose hyperkalemic group and negative (0.05 +/ 0.09 mmol/L) in the
lowdose hyperkalemic group (p < 0.05). Fibrillation was less prevalent
in the
hypocalcemichyperkalemic group (8/12) than in the other groups reperfused
with
cardioplegic solution at a dose of 500 ml/m2 (hypocalcemicnormokalemic,
10/10;
hyperkalemicnormocalcemic, 9/10) or in the group reperfused with unmodified
pump blood (12/12) (p < 0.05, hypocalcemichyperkalemic group versus
other
reperfusate groups). Reperfusioninduced ventricular fibrillation is an
indicator of reperfusion injury, and in this study the conditions of reperfusion
influenced the prevalence of reperfusioninduced ventricular fibrillation.
Recovery of aerobic metabolism during hyperkalemiainduced asystolic reperfusion
was associated with a lower prevalence of reperfusioninduced ventricular
fibrillation. Combining hypocalcemia with hyperkalemia decreased the prevalence
of reperfusioninduced ventricular fibrillation.
PMID 8361195
106: J Cardiovasc Pharmacol. 1993 Aug;22(2):2739.
Administration of intravenous calcium before verapamil to prevent hypotension
in
elderly patients with paroxysmal supraventricular tachycardia.
Miyagawa K, Dohi Y, Ogihara M, Sato K.
The aim of this study is to evaluate the effects on blood pressure and
heart
rate of i.v. calcium before the administration of verapamil during the
treatment
of paroxysmal supraventricular tachycardia (PSVT) in elderly patients.
Administration of i.v. verapamil with or without preceding i.v. calcium
administration was performed in elderly patients with PSVT. Verapamil
(1.0
mg/min) was administered i.v. in 10 patients (Group A) and calcium (3.75
mg/kg
for 5 min) followed by verapamil (1.0 mg/min), which was administered
i.v. in
seven patients (Group B). Blood pressure and heart rate were measured
during the
study every 5 minutes. Verapamil was effective in suppressing PSVT in
both
groups. In Group A, i.v. verapamil caused sustained decreases in blood
pressure
and heart rate over 25 min. In Group B, systolic blood pressure transiently
fell
immediately after administration of i.v. verapamil, but reversed to the
baseline
level in 5 min. The absolute and percentage decreases in blood pressure
were
significantly smaller in Group B than in Group A, whereas changes in heart
rate
were identical in both groups. Thus, i.v. calcium was effective in preventing
hypotension during the treatment of PSVT with verapamil. This regimen
was
beneficial for elderly patients, since a sufficient dose of verapamil
for
suppressing PSVT could be administered without causing hypotension.
PMID 7692169
107: N Engl J Med. 1993 Jun 17;328(24):174752.
Prevention of corticosteroid osteoporosis. A comparison of calcium, calcitriol,
and calcitonin.
Sambrook P, Birmingham J, Kelly P, Kempler S, Nguyen T, Pocock N, Eisman
J.
BACKGROUND. Prolonged corticosteroid therapy increases the risk of osteoporosis
and fracture. We studied whether corticosteroidinduced osteoporosis could
be
prevented by treatment with calcium, calcitriol (1,25dihydroxyvitamin
D3), and
calcitonin. METHODS. One hundred three patients starting longterm
corticosteroid therapy were randomly assigned to receive 1000 mg of calcium
per
day orally and either calcitriol (0.5 to 1.0 microgram per day orally)
plus
salmon calcitonin (400 IU per day intranasally), calcitriol plus a placebo
nasal
spray, or double placebo for one year. Data on treatment efficacy were
available
for 92 of these patients. Bone density was measured every four months
for two
years by photon absorptiometry. There were no significant differences
between
groups with respect to age, underlying disease, initial bone density,
or
corticosteroid dose during the first year. RESULTS. Calcitriol (mean dose,
0.6
microgram per day), with or without calcitonin, prevented more bone loss
from
the lumbar spine (mean rates of change, 0.2 and 1.3 percent per year,
respectively) than calcium alone (4.3 percent per year, P = 0.0035). Bone
loss
at the femoral neck and distal radius was not significantly affected by
any
treatment. In the second year, lumbar bone loss did not occur in the group
previously treated with calcitonin plus calcitriol (+0.7 percent per year),
but
it did occur in the group given calcium alone (2.3 percent per year).
The
calcitriol group also lost lumbar bone (3.6 percent per year) but received
more
corticosteroid in the second year than the other two groups. CONCLUSIONS.
Calcitriol and calcium, used prophylactically with or without calcitonin,
prevent corticosteroidinduced bone loss in the lumbar spine.
108: J Pediatr. 1993 May;122(5 Pt 1):7618.
Effect of parenteral calcium and phosphorus therapy on mineral retention
and
bone mineral content in very low birth weight infants.
Prestridge LL, Schanler RJ, Shulman RJ, Burns PA, Laine LL.
HYPOTHESIS: If calcium and phosphorus are administered to very low birth
weight
infants in amounts larger than those currently used in standard parenteral
nutrition solutions, apparent retention of calcium and phosphorus (intake
minus
urinary excretion) will increase and bone mineralization will improve.
DESIGN:
Randomized, controlled, doubleblind trial. SETTING: Neonatal intensive
care
unit. PATIENTS: Twentyfour very low birth weight infants (< 1.2 kg)
expected to
receive parenteral nutrition exclusively for approximately 3 weeks beginning
3
days after birth. INTERVENTIONS: Infants received parenteral nutrition
solutions, either the standard mixture containing 1.25 mmol calcium and
1.5 mmol
phosphorus per deciliter (group STAND: n = 12, birth weight 921 +/ 171
gm,
gestational age 27 +/ 2 weeks (mean +/ SD)) or 1.7 mmol calcium and 2.0
mmol
phosphorus per deciliter (group HIGH: n = 12, 857 +/ 180 gm, 27 +/ 2 weeks).
MAIN OUTCOME MEASURES: Intake, urinary excretion, and apparent retention
of
calcium, phosphorus, and magnesium every 3 days during parenteral nutrition
therapy. Serum indexes of mineral status twice during therapy. Bone mineral
content of the distal segment of the left radius at 1, 4, 8, and 26 weeks.
RESULTS: Apparent calcium retention (1.2 +/ 0.2 vs 1.6 +/ 0.2 mmol.kg1.d1)
and phosphorus retention (1.4 +/ 0.2 vs 1.8 +/ 0.4 mmol.kg1.d1) differed
significantly (p < 0.01) between groups STAND and HIGH, respectively;
neither
changed with the duration of parenteral nutrition therapy. Serum calcium,
magnesium, parathyroid hormone, 25hydroxyvitamin D, and osteocalcin
concentrations were similar in both groups. Serum phosphorus concentration
was
significantly higher in group HIGH than in group STAND (p = 0.025). The
absolute
bone mineral content and the rate of increase in bone mineral content
between 1
and 4, 1 and 8, and 1 and 26 weeks were significantly greater in group
HIGH than
in group STAND. CONCLUSIONS: Increased parenteral intakes of calcium and
phosphorus resulted in greater retention of these minerals during parenteral
nutrition therapy and in greater bone mineral content after therapy.
109: J Card Surg. 1993 Mar;8(2 Suppl):32931.
Calcium and stunned myocardium.
Mazer CD.
Calcium administration during ischemia or at the onset of reperfusion
is
generally considered to be deleterious because cytosolic calcium is elevated
at
this time. In contrast, the administration of calcium antagonists before
or
during ischemia is protective. While calcium antagonists may not be beneficial
when given after reperfusion, calcium administration during this period
has been
found to enhance the recovery of systolic and diastolic function of stunned
myocardium.
110: N Engl J Med. 1993 Feb 18;328(7):4604.
Effect of calcium supplementation on bone loss in postmenopausal women.
Reid IR, Ames RW, Evans MC, Gamble GD, Sharpe SJ.
BACKGROUND. The use of calcium supplements slows bone loss in the forearm
and
has a beneficial effect on the axial bone density of women in late menopause
whose calcium intake is less than 400 mg per day. However, the effect
of a
calcium supplement of 1000 mg per day on the axial bone density of
postmenopausal women with higher calcium intakes is not known. METHODS.
We
studied 122 normal women at least three years after they had reached menopause
who had a mean dietary calcium intake of 750 mg per day. The women were
randomly
assigned to treatment with either calcium (1000 mg per day) or placebo
for two
years. The bone mineral density of the total body, lumbar spine, and proximal
femur was measured every six months by dualenergy xray absorptiometry.
Serum
and urine indexes of calcium metabolism were measured at base line and
after 3,
12, and 24 months. RESULTS. The mean (+/ SE) rate of loss of totalbody
bone
mineral density was reduced by 43 percent in the calcium group (0.0055
+/
0.0010 g per square centimeter per year) as compared with the placebo
group
(0.0097 +/ 0.0010 g per square centimeter per year, P = 0.005). The rate
of
loss of bone mineral density was reduced by 35 percent in the legs (P
= 0.02),
and loss was eliminated in the trunk (P = 0.04). Calcium use was of significant
benefit in the lumbar spine (P = 0.04), and in Ward's triangle the rate
of loss
was reduced by 67 percent (P = 0.04). Calcium supplementation had a similar
effect whether dietary calcium intake was above or below the mean value
for the
group. Serum parathyroid hormone concentrations tended to be lower in
the
calcium group, as were urinary hydroxyproline excretion and serum alkaline
phosphatase concentrations. CONCLUSIONS. Calcium supplementation significantly
slowed axial and appendicular bone loss in normal postmenopausal women.
PMID 8421475
111: J Hum Hypertens. 1993 Feb;7(1):435.
Effect of oral calcium supplementation on blood pressure in patients with
previously untreated hypertension: a randomised, doubleblind,
placebocontrolled, crossover study.
Galloe AM, Graudal N, Moller J, Bro H, Jorgensen M, Christensen HR.
It has been claimed that calcium lowers BP. The present randomised,
doubleblind, placebocontrolled crossover study is the first to investigate
the
effect on BP of a high oral dose of calcium given for a long period to
patients
with previously untreated hypertension. Elemental calcium (2 g) was administered
for 12 weeks interchanging with a period of 12 weeks of placebo. Twenty
patients
completed the protocol. There was no significant difference in change
of BP
during the period of additional calcium intake when compared with placebo
(P =
0.33). The risk of not detecting a real BPlowering effect of calcium of
at
least 3 mmHg was < 5%. No evidence for the existence of a subgroup
of
'responders' was found. It is concluded that a high daily dose of calcium
supplementation given for 12 weeks does not decrease BP in previously
untreated
patients with mild to moderate hypertension.
112: N Engl J Med. 1992 Dec 3;327(23):163742.
Vitamin D3 and calcium to prevent hip fractures in the elderly women.
Chapuy MC, Arlot ME, Duboeuf F, Brun J, Crouzet B, Arnaud S, Delmas PD,
Meunier PJ.
BACKGROUND. Hypovitaminosis D and a low calcium intake contribute to
increased
parathyroid function in elderly persons. Calcium and vitamin D supplements
reduce this secondary hyperparathyroidism, but whether such supplements
reduce
the risk of hip fractures among elderly people is not known. METHODS.
We studied
the effects of supplementation with vitamin D3 (cholecalciferol) and calcium
on
the frequency of hip fractures and other nonvertebral fractures, identified
radiologically, in 3270 healthy ambulatory women (mean [+/ SD] age, 84
+/ 6
years). Each day for 18 months, 1634 women received tricalcium phosphate
(containing 1.2 g of elemental calcium) and 20 micrograms (800 IU) of
vitamin
D3, and 1636 women received a double placebo. We measured serial serum
parathyroid hormone and 25hydroxyvitamin D (25(OH)D) concentrations in
142
women and determined the femoral bone mineral density at base line and
after 18
months in 56 women. RESULTS. Among the women who completed the 18month
study,
the number of hip fractures was 43 percent lower (P = 0.043) and the total
number of nonvertebral fractures was 32 percent lower (P = 0.015) among
the
women treated with vitamin D3 and calcium than among those who received
placebo.
The results of analyses according to active treatment and according to
intention
to treat were similar. In the vitamin D3calcium group, the mean serum
parathyroid hormone concentration had decreased by 44 percent from the
baseline
value at 18 months (P < 0.001) and the serum 25(OH)D concentration
had increased
by 162 percent over the baseline value (P < 0.001). The bone density
of the
proximal femur increased 2.7 percent in the vitamin D3calcium group and
decreased 4.6 percent in the placebo group (P < 0.001). CONCLUSIONS.
Supplementation with vitamin D3 and calcium reduces the risk of hip fractures
and other nonvertebral fractures among elderly women.
113: Am J Clin Nutr. 1992 Dec;56(6):10458.
Calcium supplementation and plasma ferritin concentrations in premenopausal
women.
Sokoll LJ, DawsonHughes B.
The effect of calcium supplement use on iron stores was examined in a
randomized
controlled study in freeliving, healthy, premenopausal women. Of 109 women
who
completed the study, 52 were in the control group and 57 took two tablets
containing 250 mg Ca as the carbonate with each of two meals daily for
12 wk. In
all subjects at baseline, plasma ferritin concentrations were positively
correlated with hemeiron intake (r = 0.21, P = 0.04), serum iron concentration
(r = 0.19, P = 0.04), transferrin saturation (r = 0.31, P = 0.001), and
hemoglobin concentration (r = 0.22, P = 0.02), and negatively correlated
with
total ironbinding capacity (TIBC, r = 0.42, P < 0.001). No significant
differences in absolute or percent changes in plasma ferritin concentrations,
serum iron concentrations, TIBC, transferrin saturation, hemoglobin
concentrations, or hematocrit were observed between the treatment and
control
groups. Thus, over a 12wk period, use of 1000 mg Ca as the carbonate daily
with
meals does not appear to be detrimental to iron stores in healthy, freeliving,
premenopausal women.
114: CMAJ. 1987 Mar 15;136(6):58793.
Osteoporosis, calcium and physical activity.
Martin AD, Houston CS.
Sales of calcium supplements have increased dramatically since 1983,
as
middleaged women seek to prevent or treat bone loss due to osteoporosis.
However, epidemiologic studies have failed to support the hypothesis that
larger
amounts of calcium are associated with increased bone density or a decreased
incidence of fractures. The authors examine the evidence from controlled
trials
on the effects of calcium supplementation and physical activity on bone
loss and
find that weightbearing activity, if undertaken early in life and on a
regular
basis, can increase the peak bone mass of early adulthood, delay the onset
of
bone loss and reduce the rate of loss. All of these factors will delay
the onset
of fractures. Carefully planned and supervised physical activity programs
can
also provide a safe, effective therapy for people who have osteoporosis.
PMID 3545420
115: Nutr Rev. 1992 Nov;50(11):3357.
Maximizing peak bone mass: calcium supplementation increases bone mineral
density in children.
[No authors listed]
Attaining peak skeletal bone mass during childhood may reduce the incidence
of
osteoporosis in later life. A recent study in six to 14yearold identical
twins showed that calcium supplementation increased bone mineral density.
The
effects of supplementation were especially pronounced in prepubertal children.
PMID 1488160
116: Nutr Rev. 1992 Aug;50(8):2336.
Calcium supplementation prevents hypertensive disorders of pregnancy.
[No authors listed]
Preeclampsia, a hypertensive disorder of pregnancy, is a major cause
of fetal
and maternal morbidity and mortality. Epidemiologic studies have shown
an
inverse relationship between dietary calcium intake and gestational
hypertension. A recent largescale, randomized, doubleblind, placebocontrolled
clinical trial has shown that supplementation of pregnant women with 2
g calcium
per day from the twentieth week of gestation to term can significantly
lower the
incidence of hypertensive disorders of pregnancy. The beneficial effect
of
calcium supplementation was apparent as early as the twentyeighth week
of
gestation. The mechanism responsible for the effects of calcium on gestational
hypertension is unknown.
PMID 1345035
117: Zhonghua Xin Xue Guan Bing Za Zhi. 1992 Aug;20(4):2434, 261.
[Protective effects of gradual restoring of calcium on working rat hearts
with
ischemiareperfusion injury]
Xie SP.
The effects of gradually restoring calcium concentration in initiating
reperfusion on cardiac function, coronary blood flow and myocardial calcium
content during reperfusion following global ischemia have been observed
in
isolated working rat hearts. The results showed that gradually restoring
calcium
reperfusion facilitated the recovery of the contracting relaxing and pump
functions as well as coronary blood flow, and decreased the occurrence
of
arrhythmias during reperfusion and myocardial calcium content after reperfusion.
The mechanism of the protective effect of gradual calcium restoration
on the
hearts was probably due to the inhibition of calcium overload in cardiac
cells.
However high calcium reperfusion deteriorated cardiac function.
118: Gastroenterology. 1992 Jul;103(1):927.
Calcium supplementation decreases rectal epithelial cell proliferation
in
subjects with sporadic adenoma.
Wargovich MJ, Isbell G, Shabot M, Winn R, Lanza F, Hochman L, Larson E,
Lynch P,
Roubein L, Levin B.
The results of three small clinical trials examining the effect of calcium
carbonate supplementation on the proliferation cytokinetics of the rectal
epithelium in subjects with a current history of sporadic adenoma are
reported.
In six subjects, a daily administration of 1500 mg of calcium carbonate
for 90
days failed to significantly suppress thymidine labeling in normalappearing
mucosa of the rectum. However, a daily dose of 2000 mg of calcium significantly
(P = 0.008) altered mucosal proliferation in a second set of six subjects
after
a 30day trial. Finally, a placebocontrolled trial of calcium (2000 mg)
was
conducted in which 20 subjects were randomized to groups receiving a 4week
intervention with calcium (or placebo), followed by the alternative treatment
(placebo or calcium). The results of the study show a marked suppression
of
rectal proliferation during the calcium phase of the study but not during
the
placebo phase. This study adds to accumulating evidence showing that calcium
supplementation regulates the proliferative behavior of colonic epithelium
in
the individual at high risk for colon cancer. Longer term trials of calcium
supplementation will ascertain whether a continuing benefit from increasing
dietary calcium translates into inhibition of adenoma recurrence.
119: Radiology. 1992 Jul;184(1):15964.
Amelioration of cardiodepressive effects of gadopentetate dimeglumine
with
addition of ionic calcium.
Muhler A, Saeed M, Brasch RC, Higgins CB.
Doses of gadopentetate dimeglumine of 0.10.5 mmol/kg cause cardiodepressive
effects when injected as a rapid central bolus into the left jugular vein.
This
study evaluated the hemodynamic effects of this magnetic resonance imaging
contrast medium with and without calcium supplementation in a rat model.
Also,
the potential of gadopentetate dimeglumine to bind ionized serum calcium
was
investigated in vitro. Addition of calcium ions resulted in dosedependent
attenuation of the hemodynamic depression induced by gadopentetate dimeglumine
alone. The cardiodepressive response was negated for a 0.1mmol/kg dose
of the
contrast agent by addition of 6 mumol/kg of calcium, for a 0.3mmol/kg
dose by
addition of 12 mumol/kg of calcium, and for a 0.5mmol/kg dose by addition
of 18
mumol/kg of calcium. Concentrations of 2 and 4 mmol/L of gadopentetate
dimeglumine were found to bind 5.1% and 10.1% of the ionized calcium in
rat
serum under in vitro conditions, respectively.
PMID 1609076
120: Acta Physiol Scand. 1992 Jun;145(2):938.
Calcium supplementation and thyroid hormone protect against gentamicininduced
inhibition of proximal tubular Na+,K(+)ATPase activity and other renal
functional changes.
Fukuda Y, Eklof AC, Malmborg AS, Aperia A.
Gentamicin can cause proximal tubule necrosis. We have shown that inhibition
of
PT Na+,K(+)ATPase activity is rapidly induced by gentamicin. We have now
investigated whether manipulations known to attenuate the negative effects
of
gentamicin on renal excretory capacity, i.e. high calcium intake and Lthyroxine
treatment, will also attenuate gentamicininduced inhibition of Na+,K(+)ATPase
activity and ameliorated signs of proximal tubule damage. Rats were gentamicin
or vehicletreated for 7 days. Subgroups were given 4% calcium (Ca) supplements
or Lthyroxine 20 micrograms 100 g1 body weight daily. Gentamicin significantly
reduced the glomerular filtration rate and increased the urinary excretion
of
the proximal tubule lysosomal enzyme, NacetylbetaDglucosaminidase.
Gentamicin significantly reduced proximal tubule Na+,K(+)ATPase activity,
measured in single permeabilized proximal tubule segments. Sodium excretion
was
inversely correlated to proximal tubule Na+,K(+)ATPase activity. Both
calcium
and Lthyroxine alleviated all gentamicininduced sideeffects on renal function
as well as on proximal tubule Na+,K(+)ATPase activity. Calcium and Lthyroxine
had no significant effect on renal function. Lthyroxine, but not calcium,
increased proximal tubule Na+,K(+)ATPase activity in control rats. Renal
cortical tissue gentamicin concentration was not influenced by calcium
but was
significantly lowered by Lthyroxine. Two procedures which, via different
mechanisms, afford protection from gentamicininduced changes in renal
function
also give protection from gentamicininduced inhibition of Na+,K(+)ATPase
activity. This suggests that loss of integrity of the Na+,K(+)ATPase enzyme
contributes to gentamicininduced nephrotoxicity.
PMID 1322021
121: Vnitr Lek. 1992 Apr;38(4):3526.
[Diabetic osteopathy. Favorable effect of treatment of osteomalacia with
vitamin
D and calcium on high blood glucose levels]
Kocian J.
A group of 61 diabetics (incl. 35 treated by diet alone and 26 who were
treated
also by oral antidiabetics) with associated osteomalacia were treated
with
vitamin D (dosage 42,000 to 85,000 i. u. per day) and calcium (470700
mg/day).
After six weeks of this treatment the serum calcium level rose on average
by
0.15 mmol/l and the blood sugar level declined on average by 1.68 mmol/l.
A
linear negative correlation was proved between these two parameters. The
fasting
blood sugar level declined in 53 subjects (86.88%) and only in five patients
(8.19%) the blood sugar level increased, in three subjects (4.91%) it
did not
change. Possible explanations of this phenomenon include the influence
of an
increased calcium concentration on insulin secretion and release from
pancreatic
betacells on the one hand and enhanced glucose utilization in the periphery
on
the other hand.
122: N Engl J Med. 1992 Feb 6;326(6):35762.
Treatment of postmenopausal osteoporosis with calcitriol or calcium.
Tilyard MW, Spears GF, Thomson J, Dovey S.
BACKGROUND AND METHODS. Osteoporosis is a common problem whose management
is controversial. To evaluate the efficacy and safety of calcitriol
(1,25dihydroxyvitamin D3) in the treatment of postmenopausal osteoporosis,
we
conducted a threeyear prospective, multicenter, singleblind study in 622
women
who had one or more vertebral compression fractures. The women were randomly
assigned to receive treatment with calcitriol (0.25 micrograms twice a
day) or
supplemental calcium (1 g of elemental calcium daily) for three years.
New
vertebral fractures were detected by means of lateral roentgenography
of the
spine each year, and calcium absorption was measured in 392 of the women.
RESULTS. The women who received calcitriol had a significant reduction
in the
rate of new vertebral fractures during the second and third years of treatment,
as compared with the women who received calcium (second year, 9.3 vs.
25.0
fractures per 100 patientyears; third year, 9.9 vs. 31.5 fractures per
100
patientyears; P less than 0.001). This effect was evident only in women
who had
had five or fewer vertebral fractures at base line (second year, 5.2 vs.
25.3
fractures per 100 patientyears; third year, 4.2 vs. 31.0 fractures per
100
patientyears; P less than 0.0001). The groups also differed significantly
in
the number of peripheral fractures; 11 such fractures occurred in 11 women
in
the calcitriol group, whereas 24 occurred in 22 women in the calcium group
(P
less than 0.05). There was no significant difference between the groups
in the
incidence of side effects requiring withdrawal of treatment (8.6 percent
in the
calcitriol group vs. 6.5 percent in the calcium group). CONCLUSIONS. Continuous
treatment of postmenopausal osteoporosis with calcitriol for three years
is safe
and significantly reduces the rate of new vertebral fractures in women
with this
disorder.
123: Clin Nephrol. 1992 Jan;37(1):148.
Reduction of urinary oxalate by combined calcium and citrate administration
without increase in urinary calcium oxalate stone formers.
Ito H, Suzuki F, Yamaguchi K, Nishikawa Y, Kotake T.
Oxalic acid seems to play a far greater role in the formation of calcium
oxalate
stone than calcium. Three grams of calcium lactate and 3 g of sodium potassium
citrate were administered to 46 urolithiasis patients, whose stones were
mainly
composed of calcium oxalate. Urinary oxalate level was reduced significantly
without raising urinary calcium level by the administration of the two
drugs for
two weeks. The reduction of urinary oxalic acid was particularly remarkable
in
patients without hypercalciuria. The mechanism of action of these drugs
was
discussed.
PMID 1541059
124: N Engl J Med. 1991 Nov 14;325(20):1399405.
Calcium supplementation to prevent hypertensive disorders of pregnancy.
Belizan JM, Villar J, Gonzalez L, Campodonico L, Bergel E.
BACKGROUND. Calcium supplementation has been reported to reduce blood
pressure
in pregnant and nonpregnant women. We undertook this prospective study
to
determine the effect of calcium supplementation on the incidence of hypertensive
disorders of pregnancy (gestational hypertension and preeclampsia) and
to
determine the value of urinary calcium levels as a predictor of the response.
METHODS. We studied 1194 nulliparous women who were in the 20th week of
gestation at the beginning of the study. The women were randomly assigned
to
receive 2 g per day of elemental calcium in the form of calcium carbonate
(593
women) or placebo (601 women). Urinary excretion of calcium and creatinine
was
measured before calcium supplementation was begun. The women were followed
to
the end of their pregnancies, and the incidence of hypertensive disorders
of
pregnancy was determined. RESULTS. The rates of hypertensive disorders
of
pregnancy were lower in the calcium group than in the placebo group (9.8
percent
vs. 14.8 percent; odds ratio, 0.63; 95 percent confidence interval, 0.44
to
0.90). The risk of these disorders was lower at all times during gestation,
particularly after the 28th week of gestation (P = 0.01 by lifetable analysis),
in the calcium group than in the placebo group, and the risk of both gestational
hypertension and preeclampsia was also lower in the calcium group. Among
the
women who had low ratios of urinary calcium to urinary creatinine (less
than or
equal to 0.62 mmol per millimole) during the 20th week of gestation, those
in
the calcium group had a lower risk of hypertensive disorders of pregnancy
(odds
ratio, 0.56; 95 percent confidence interval, 0.29 to 1.09) and less of
an
increase in diastolic and systolic blood pressure than the placebo group.
The
pattern of response was similar among the women who had a high ratio of
urinary
calcium to urinary creatinine during the 20th week of gestation, but the
differences were smaller. CONCLUSIONS. Pregnant women who receive calcium
supplementation after the 20th week of pregnancy have a reduced risk of
hypertensive disorders of pregnancy.
125: Am J Hypertens. 1991 Oct;4(10 Pt 1):8369.
Calcium treatment of essential hypertension in elderly patients evaluated
by 24
H monitoring.
Takagi Y, Fukase M, Takata S, Fujimi T, Fujita T.
We used 24h monitoring of blood pressure (BP) to evaluate the effect
of calcium
supplementation on mild to moderate essential hypertension in elderly
hospitalized patients for the first time in a controlled crossover study.
The
mean systolic and diastolic BP over a period of 24 h declined by 13.6
mm Hg (P
less than .005) and 5.0 mm Hg (P less than .05) respectively in patients
whose
diet was supplemented with 1 g of elemental calcium in the form of oystershell
electrolysate (AA calcium). Serum ionized calcium and urinary calcium
and sodium
excretion increased (serum Ca2+ 0.16 +/ 0.03 mEq/L, P less than .05; FECa
0.5
+/ 0.2%, P less than .05; FENa 0.4 +/ 0.1%, P less than .05) and plasma
parathyroid hormone was suppressed (12.2 +/ 2.3 pg/mL, P less than .005).
These
data suggest that supplementation of dietary calcium may contribute to
a
reduction of BP in elderly patients with essential hypertension.
126: Hinyokika Kiyo. 1991 Oct;37(10):110710.
[Combined administration of calcium and citrate reduces urinary oxalate
excretion]
Ito H.
Three grams of calcium lactate and 3 g of uralyt U were administered
to 39
calcium oxalate stone formers. Urinary oxalate level was reduced significantly
without raising urinary calcium level by the administration of the two
drugs for
two weeks. The mechanism of action of these drugs and the diet which might
produce a similar effect were discussed.
127: J Clin Endocrinol Metab. 1991 Sep;73(3):53340.
Calcium supplementation reduces vertebral bone loss in perimenopausal
women: a
controlled trial in 248 women between 46 and 55 years of age.
Elders PJ, Netelenbos JC, Lips P, van Ginkel FC, Khoe E, Leeuwenkamp OR,
Hackeng
WH, van der Stelt PF.
To study the effect of calcium supplementation on perimenopausal bone
loss, 295
women were randomized into a control group and 2 supplementation groups
receiving, respectively, 1000 and 2000 mg elemental calcium/day for a
period of
2 yr. We observed a significant decrease in lumbar bone loss in relation
to the
calcium supplementation (mean loss after 2 yr of 3.5% in the control group
vs.
1.3% and 0.7% in the 1000 and 2000 mg groups, respectively), a significant
increase in urinary calcium excretion, and a significant decrease in the
urinary
hydroxyproline/creatine ratio, serum alkaline phosphatase, osteocalcin,
and
1,25dihydroxyvitamin D. The effect of calcium supplementation on lumbar
bone
loss was significant in the first year of supplementation, but not in
the
second. However, the urinary hydroxyproline/creatinine ratio and the serum
alkaline phosphatase level remained significantly decreased in the treatment
groups at the end of the study; this was not the case for serum osteocalcin.
Calcium supplementation did not have a significant effect on metacarpal
cortical
bone loss. The difference in biochemical parameters between the 2
supplementation groups was small. No significant interaction was observed
between the menopausal status of the subjects and the effect of calcium
supplementation. We conclude that calcium supplementation retards lumbar
bone
loss in the first year of calcium supplementation by reducing bone turnover.
However, the effect on lumbar bone loss over a longer time span is still
uncertain.
128: Am J Clin Nutr. 1991 Aug;54(2):4258.
Influence of calcium intake and growth indexes on vertebral bone mineral
density
in young females.
Sentipal JM, Wardlaw GM, Mahan J, Matkovic V.
This crosssectional study examined the relationship between current calcium
intake and vertebral bone mineral density (VBMD) in 49 healthy Caucasian
adolescent females aged 818 y. The ability of current calcium intake to
account
for the variance in VBMD in this population was compared with that seen
with
weight, height, maturational age (determined by the Tanner Sexual Maturity
Rating), chronological age, and total energy expenditure. Calcium intake
was
determined from the mean of 4d, foodintake records. Average vertebral
bone
mineral density from L1L4 was measured by dual xray absorptiometry. A
multipleregression model revealed that 81% of the variance in VBMD was
described by maturational age, chronological age, and calcium intake,
with all
representing significant predictors of bone mineral density (P less than
0.0001,
0.005, 0.04, respectively). This study supports the hypothesis that better
calcium nutrition during adolescence may optimize, within genetic boundaries,
peak bone mass.
PMID 1858707
129: Bol Oficina Sanit Panam. 1991 Feb;110(2):12635.
[Use of calcium for the prevention of pregnancyinduced hypertension]
LopezJaramillo P, de Felix M.
The Andean population of Ecuador is exposed to major risk factors associated
with pregnancyinduced hypertension (PIH). The disease is very frequent,
and
perinatal and maternal death rates are high. Recently a causal relationship
has
been suggested between dietary calcium deficiency and PIH, with the proposal
that calcium supplements be given throughout pregnancy in order to prevent
the
disease. This article reviews a series of clinical tests carried out over
a
sixyear period which have demonstrated that calcium supplementation is
an
effective lowcost measure for reducing the frequency of PIH in women whose
intake of the mineral is low. It is not yet known how calcium reduces
the risk
of PIH. It is suggested that adequate intake of the mineral keeps serum
levels
of calcium within its narrow physiological limits; these are crucial for
the
synthesis of nitric oxide in the vascular endothelium, a substance that
appears
to be responsible for maintaining the vasodilatation that characterizes
normal
pregnancy. However, before the general use of calcium supplements can
be
recommended, it will be necessary to conduct epidemiological studies on
larger
numbers of women.
130: Clin Ter. 1990 Oct 31;135(2):95103.
[Calcium folinate in old age]
Baroni MC, Delsignore R, Cuzzupoli M, Candelora P, Passeri M.
The authors report the results obtained in a group of 60 elderly patients
(age
greater than or equal to 65 years) treated with a 15 mg tablet of calcium
folinate per day for 60 days. The drug was very well tolerated and it
significantly improved the blood chemistry and clinical parameters considered.
131: Am J Obstet Gynecol. 1990 Oct;163(4 Pt 1):112431.
Calcium supplementation during pregnancy may reduce preterm delivery in
highrisk populations.
Villar J, Repke JT.
Results are presented of a randomized, doubleblinded controlled clinical
trial
of calcium supplementation (2.0 gm of elemental calcium as calcium carbonate)
and a placebo. All participants were 17 years of age or less and clinically
healthy. Patients were enrolled by the twenty third week of gestation.
The mean
duration of calcium supplementation or placebo was approximately 14 weeks.
Treatment consisted of 2.8 (+/ 1.5) tablets per day in the placebo group
(N =
95) and 3.0 (+/ 1.4) tablets per day in the calcium group (N = 94). Dietary
calcium intake was similar in both groups at about 1200 mg/day. The calcium
group had a lower incidence of preterm delivery (less than 37 weeks; 7.4%
vs
21.1%; p = 0.007); spontaneous labor and preterm delivery (6.4% vs 17.9%;
p =
0.01); and low birth weight (9.6% vs 21.1%; p = 0.03). This effect was
also
present after stratified analysis by level of treatment compliance, urinary
tract infection, and chlamydial infection. Lifetable analysis demonstrated
an
overall shift to a higher gestational age in the calcium group compared
with the
placebo group (logrank test, p = 0.02). As suggested previously, the observed
effect could be mediated by a reduction in uterine smooth muscle
contractibility. If confirmed by future research, these results could
represent
an important preventive intervention for prematurity in highrisk populations.
132: N Engl J Med. 1990 Sep 27;323(13):87883.
A controlled trial of the effect of calcium supplementation on bone density
in
postmenopausal women.
DawsonHughes B, Dallal GE, Krall EA, Sadowski L, Sahyoun N, Tannenbaum
S.
Background. The effectiveness of calcium in retarding bone loss in older
postmenopausal women is unclear. Earlier work suggested that the women
who were
most likely to benefit from calcium supplementation were those with low
calcium
intakes. Methods. We undertook a doubleblind, placebocontrolled, randomized
trial to determine the effect of calcium on bone loss from the spine,
femoral
neck, and radius in 301 healthy postmenopausal women, half of whom had
a calcium
intake lower than 400 mg per day and half an intake of 400 to 650 mg per
day.
The women received placebo or either calcium carbonate or calcium citrate
malate
(500 mg of calcium per day) for two years. Results. In women who had undergone
menopause five or fewer years earlier, bone loss from the spine was rapid
and
was not affected by supplementation with calcium. Among the women who
had been
postmenopausal for six years or more and who were given placebo, bone
loss was
less rapid in the group with the higher dietary calcium intake. In those
with
the lower calcium intake, calcium citrate malate prevented bone loss during
the
two years of the study; its effect was significantly different from that
of
placebo (P less than 0.05) at the femoral neck (mean change in bone density
[+/
SE], 0.87 +/ 1.01 percent vs. 2.11 +/ 0.93 percent), radius (1.05 +/ 0.75
percent vs. 2.33 +/ 0.72 percent), and spine (0.38 +/ 0.82 percent vs.
2.85
+/ 0.77 percent). Calcium carbonate maintained bone density at the femoral
neck
(mean change in bone density, 0.08 +/ 0.98 percent) and radius (0.24 +/
0.70
percent) but not the spine (2.54 +/ 0.85 percent). Among the women who
had
been postmenopausal for six years or more and who had the higher calcium
intake,
those in all three treatment groups maintained bone density at the hip
and
radius and lost bone from the spine. Conclusions. Healthy older postmenopausal
women with a daily calcium intake of less than 400 mg can significantly
reduce
bone loss by increasing their calcium intake to 800 mg per day. At the
dose we
tested, supplementation with calcium citrate malate was more effective
than
supplementation with calcium carbonate.
133: Arzneimittelforschung. 1990 Sep;40(9):9847.
[Reduction of reactivity to allergic rhinitis with intravenous administration
of
calcium. Clinicalexperimental study on the effect of changes of local
airway
resistance after nasal allergen provocation]
Bachert C, Drechsler S, Keilmann A, Seifert E, Schmidt R, Welzel D.
The antiallergic activity of calcium was investigated in 25 patients
with
allergic rhinitis by nasal provocation with increasing doses of phleum
pratense
during a symptom free interval. Prior to that provocation, the patients
received
9 mmol calcium (CalciumSandoz) i.v. or placebo respectively (double blind
crossover design). The concentration of serum calcium increased after
calcium
injection by 0.45 +/ 0.055 mmol/l. Calcium exerted a significant protective
effect as compared to placebo: higher allergen doses, (p = 0.021) i.e.
20433
biological units/ml vs. 7494 biological units/ml, were required in order
to
induce a defined allergic reaction (50% decrease of nasal air flow). The
data
thus furnish evidence that intravenous calcium reduces the allergic response
in
type I allergy.
134: Am Heart J. 1990 Aug;120(2):3816.
Hypocalcemic myocardial dysfunction: short and longterm improvement with
calcium replacement.
Wong CK, Lau CP, Cheng CH, Leung WH, Freedman B.
The effects of short and longterm calcium replacement on myocardial function
in six asymptomatic patients (age 48 +/ 3, mean +/ SEM) with hypocalcemia
complicating surgical hypoparathyroidism were studied. Cardiac output
was
determined by ascending aortic continuous wave Doppler assessment and
was
measured as minute distance. During intravenous calcium replacement at
rest,
ascending aortic minute distance increased from 6.75 +/ 1.10 to 9.17 +/
1.29 m
as the calcium level rose from 1.76 +/ 0.08 to 2.06 +/ 0.19 mmol/L without
changes in heart rate and blood pressure (p less than 0.01). The peak
velocity
and acceleration of blood flow derived from Doppler measurement showed
a similar
rise during calcium infusion. Symptomlimited cycle ergometry was performed
before and 3 months after normalization of calcium by longterm oral therapy.
Although the resting cardiac output was unchanged, the maximum cardiac
output at
peak exercise also increased from a minute distance of 11.58 +/ 1.84 to
15.37
+/ 2.28 m (p less than 0.05), together with an increase of maximum heart
rate
from 136 to 149 beats/min (p less than 0.05). Exercise duration was also
prolonged from 11.9 +/ 2.9 to 13.0 +/ 2.8 minutes. Thus hypocalcemia impairs
cardiac performance, but this impairment is reversible with calcium replacement.
PMID 2382615
135: J Nutr. 1990 Aug;120(8):87681.
Effect of calcium citratemalate on skeletal development in young, growing
rats.
Kochanowski BA.
It has been previously demonstrated that calcium from calcium citratemalate
(CCM), a mixture of calcium, citric acid and malic acid, is betterabsorbed
than
calcium from calcium carbonate (CaCO3) in humans and in rats. It was of
interest
to determine if this differential in absorption would result in differences
in
bone development under chronic feeding conditions. The present study was
designed to compare CCM with CaCO3 for effects on bone development in
weanling
female C/D rats fed either CCM or CaCO3 at 0.3 or 0.6% dietary Ca for
4 or 12
wk. There was a nonsignificant trend for rats fed CCM to weigh more and
have
larger bones than rats fed CaCO3. Histologic evaluation of cortical and
trabecular bone revealed normal bone formation in all rats. Trabecular
bone was
significantly affected by calcium level and source. The 0.3% Ca diets
(either
source) resulted in reduced trabecular bone volumes in tibias. After 4
wk, rats
fed CCM had 2325% more trabecular bone than rats fed CaCO3. By 12 wk,
the
difference was even greater; rats fed CCM had 4447% more trabecular bone
than
rats fed CaCO3. Dietary calcium source did not affect cortical bone. It
is
concluded that because of its positive effects on bone, CCM is a more
bioavailable calcium source than CaCO3.
PMID 2380795
136: Chest. 1990 May;97(5):11069.
Shortterm control of supraventricular tachycardia with verapamil infusion
and
calcium pretreatment.
Barnett JC, Touchon RC.
Nineteen consecutive patients with atrial fibrillation/flutter or other
types of
supraventricular tachycardia were given intravenous (IV) calcium salts
(1 g)
followed by verapamil infusion at a rate of 1 mg/min. Successful treatment
was
defined as control of ventricular response to less than or equal to 100
beats
per minute (bpm) or conversion to sinus mechanism in patients with atrial
arrhythmias: 11 patients had atrial fibrillation; three had atrial flutter;
four
had reentrant supraventricular tachycardias (SVT); and one had paroxysmal
SVT.
Therapy was successful in all patients. The mean dose of verapamil required
to
achieve desired outcome was 20 mg. Heart rate showed no significant change
as a
result of calcium pretreatment (160 bpm v 151 bpm). However, heart rate
was
significantly decreased, to 95 bpm, after treatment with verapamil. Blood
pressure showed no change from baseline with either calcium or verapamil
therapy. Verapamil infusion following IV calcium successfully treats atrial
fibrillation/flutter or SVTs without depressing systemic blood pressure.
PMID 2331904
137: J Clin Endocrinol Metab. 1990 Jan;70(1):26470.
Dietary modification with dairy products for preventing vertebral bone
loss in
premenopausal women: a threeyear prospective study.
Baran D, Sorensen A, Grimes J, Lew R, Karellas A, Johnson B, Roche J.
The effect of dietary calcium on vertebral bone mass in women is controversial.
In a randomized study we have investigated the effect of dietary modification
in
the form of dairy products on vertebral bone mass in 30 to 42yrold
premenopausal women over a 3yr period. Twenty women increased their dietary
calcium intake by an average of 610 mg/day (P less than 0.03) for 3 yr,
while 17
age and weightmatched women served as controls. Calcium intake was monitored
by 3day diet histories and 24h urinary calcium excretion. The consumption
of
the dairy products did not alter serum calcium or PTH levels or the fasting
urinary calcium to creatinine ratio. Twentyfourhour urinary calcium excretion
increased by 28% (P less than 0.03) in the supplemented women. Dairy product
intake was accompanied by increased dietary fat intake, but there were
no
statistically significant changes in serum cholesterol, low density lipoprotein
cholesterol, or high density lipoprotein cholesterol levels. The vertebral
bone
density in the women consuming increased calcium did not change over the
3yr
period (0.4 +/ 0.9%). In contrast, the vertebral bone density in the control
women declined (2.9 +/ 0.8%; P less than 0.001) and was significantly
lower
than that in the supplemented group at 30 and 36 months. The study suggests
that
dietary modification in the form of dairy products retards vertebral bone
loss
in premenopausal women. Therefore, increased calcium intake in estrogenreplete
premenopausal women may prevent agerelated bone loss.
138: Zentralbl Gynakol. 1989;111(21):14414.
Zinc, magnesium and copper in serum of women given a calcium supplement.
Jendryczko A, Tomala J, Drozdz M.
Earlier investigators have demonstrated in animal studies interrelationships
between mineral elements. Serum zinc, magnesium and copper were monitored
over a
two year period in 120 women between the ages of 40 and 55 years. One
group (65
women) was supplemented with calcium, the other served as a control. We
concluded that calcium supplementation at a level of 1,500 mg Ca mainly
does not
affect serum zinc, magnesium and copper, however, serum copper concentration
is
elevated in women taking medication for hypertension.
PMID 2603586
139: Magnes Res. 1988 Dec;1(34):14753.
Consequences of low dietary magnesium and high dietary calcium on pregnancy
outcome and tissue mineralization in rats.
Pinkham CS, Kubena KS.
Weanling female SpragueDawley rats were fed purified diets to determine
the
influence of excess dietary calcium upon tissue content of magnesium and
calcium, and reproductive outcome. Two levels of calcium (5000 and 16,000
ppm)
and magnesium (200 and 1200 ppm) in a 2x2 factorial design (adequate magnesium
and calcium = C; low magnesium adequate calcium = L; high calcium adequate
magnesium = CHC; and high calcium low magnesium = LHC) were used during
the
study which included growth and breeding (10 weeks), and gestation and
lactation
(6 weeks). Depressed weight gain during growth and gestation occurred
in
response to calcium excess. Renal calcium accumulation was reduced in
LHC dams
as compared to L dams. In dams fed excess calcium, magnesium concentrations
of
bone, serum, and kidney were depressed while serum alkaline phosphatase
activity
increased. The adverse effects of high calcium seen in the dams were not
apparent in LHC pups. These pups were heavier and more viable during lactation
than pups in the L group. High dietary calcium in combination with low
dietary
magnesium during one reproductive cycle resulted in altered mineral levels
in
tissues and improved growth and viability of pups when compared to
magnesiumdeficient animals.
PMID 3275202
140: Scand J Gastroenterol. 1988 Dec;23(10):123740.
Treatment of chronic diarrhoea: loperamide versus ispaghula husk and calcium.
Qvitzau S, Matzen P, Madsen P.
Twentyfive patients with chronic diarrhoea were included in an open,
randomized
crossover trial comparing the effect of loperamide with ispaghula and
calcium.
Nineteen patients completed both treatments. Before treatment the median
number
of daily stools was 7 (range, 413), stool consistency was loose in all,
and
urgency was present in 16 out of 19 patients. Both treatments halved stool
frequency, but with regard to urgency and stool consistency ispaghula
and
calcium was significantly better. A combination of ispaghula and calcium
seems
to be a cheap and effective alternative to conventional treatment of chronic
diarrhoea. Moreover, side effects were minimized.
141: Drug Intell Clin Pharm. 1988 JulAug;22(78):5756.
Verapamil preceded by calcium in supraventricular tachycardia.
Stringer KA, Hicks P, Royal SH, Branconi JM, Sloan R.
Verapamil has been shown to be effective in the management of supraventricular
tachycardia (SVT). However, the utility of verapamil may be limited because
of
adverse effects, specifically hypotension. Several clinical observations
have
shown that the intravenous administration of calcium is effective in reversing
the myocardial depressant effects of verapamil. We report the case of
a patient
with SVT and a systolic blood pressure of 80 mm Hg in which the administration
of calcium chloride prior to that of verapamil may have negated
verapamilinduced hypotension.
PMID 3416743
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