Dietary and Lifestyle Management of Heart Failure
Cessation of Tobacco and Excessive Alcohol Use
Intake of more than 7–8 alcoholic drinks per day for more than 5 years may increase the risk of cardiovascular dysfunction that can lead to heart failure. Patients with a history of alcohol overconsumption are encouraged to abstain from drinking (Hunt 2009). However, light-to-moderate drinking (up to 1 drink daily for women and 2 drinks daily for men) may be associated with a reduced risk of heart failure compared to those who abstain from drinking (Bryson 2006; Djousse 2008; Piano 2002).
Smoking is a major risk factor for many medical conditions, including cardiovascular diseases. Stopping smoking was shown to provide benefits for patients with congestive heart failure, which are similar to the benefits offered by primary drugs used in this condition (CDC 2010; Suskin 2001). Several other studies found that people who quit smoking have a lower risk of cardiovascular disease (Clair 2013).
Restriction of Dietary Sodium
A high dietary intake of salt increases blood pressure, and is well-known to worsen hypertension, a major cause of heart failure (He 2011). A prospective study of over 10 000 volunteers showed that for every 100 mmol sodium (about 5.8 g of sodium chloride [table salt]) consumed per day, the relative risk of heart failure increased by 26% (He 2002). The American Dietetic Association guideline for dietary sodium in heart failure patients is <2 g/day, with the intent to improve both clinical symptoms, such as tiredness and swelling, and quality of life (Tyson 2012). A sodium-restricted diet (<1.5 g/day) in patients with hypertension can help reduce blood pressure. The DASH (Dietary Approaches to Stop Hypertension) eating plan, which is rich in fruits, vegetables, and low-fat dairy products, has been shown to lower systolic blood pressure by 8-14 mmHg (Sacks 2001; Tejada 2006). The DASH diet had a beneficial impact on blood pressure at high, intermediate, and low levels of dietary sodium intake, and researchers observed that the two interventions combined had a stronger impact on lowering blood pressure than either alone (Sacks 2001). The DASH diet may be appropriate to use for the prevention and management of chronic heart failure. Diets consistent with the DASH eating pattern have been associated with lower rates of heart failure in women and lower rates of hospitalization (due to heart failure) or death in men (Tyson 2012).
Monitor Micronutrient Sufficiency
Micronutrient deficiencies play an important role in the progression of heart failure. The frequency of malnutrition increases with the degree of heart failure severity, ranging from an estimated 22% in NYHA class II patients to 63% in class III patients (Dunn 2009). Micronutrient insufficiency is of particular concern among patients on certain heart failure medications.
- Potassium and zinc. Diuretic use is associated with electrolyte depletion. Among electrolytes, the depletion of potassium is most worrisome because it is essential for maintenance of normal heart rhythm and function. Conversely, ACE inhibitors and ARBs decrease the excretion of potassium and may lead to elevated potassium levels. In addition to their effects on potassium, ACE inhibitors and ARBs have been shown to increase the urinary excretion of zinc, and thiazide diuretics also increase urinary zinc losses (Dunn 2009).
- Magnesium, calcium, and phosphate. Loop diuretics increase magnesium, phosphate, and calcium excretion from the kidney (Dunn 2009). In a study completed by 68 patients admitted to the hospital for heart failure, 38% presented with low magnesium levels at admission and 72% had excessive urinary magnesium loss (Ceremuzyński 2000).
Several clinical trials have investigated the use of magnesium in heart failure patients. In one trial, 300 mg of magnesium citrate was found to improve heart rate variability after 5 weeks of supplementation (Almoznino-Sarafian 2009). Magnesium oxide, at a dose of 800 mg daily for 3 months, improved arterial elasticity compared to placebo in individuals with chronic heart failure (Fuentes 2006). In another trial, magnesium orotate (6000 mg daily for 1 month, 3000 mg daily for 11 months) or placebo was given to patients with severe congestive heart failure. The survival rate after 1 year of supplementation was 76% for the magnesium group vs. 52% for the placebo group. The authors concluded “Magnesium orotate may be used as adjuvant therapy in patients on optimal treatment for severe congestive heart failure, increasing survival rate and improving clinical symptoms and patient’s quality of life” (Stepura 2009).
- B-vitamins. Chronic therapy with diuretics, which are administered to many patients with heart failure, may prevent the reabsorption of thiamine and increase its urinary excretion, contributing to thiamine deficiency. A study in 25 patients with heart failure found that furosemide (Lasix®) use at 80 mg or more per day was associated with a 98% prevalence of thiamine deficiency (Dunn 2009). Deficiencies of several vitamins, including riboflavin, pyridoxine, folic acid, and B12 have also been documented in heart failure patients. Riboflavin, B12, and folic acid play a role in homocysteine metabolism. Homocysteine is an amino acid that can cause damage to the inner lining of blood vessels – the endothelium. Elevated homocysteine levels have been associated with a poor prognosis in heart failure patients (Azizi-Namini 2012; Krim 2013).
Exercise training is now recognized as a valuable addition to other interventions and should be considered for all heart failure patients who are stable enough to participate (Hunt 2009). Experimentally, exercise was shown to slow the progression of heart failure. ACCF/AHA guidelines recommend that aerobic activity be performed for at least 30 minutes, 5 or more days per week. Published studies evaluating the efficacy of exercise training in heart failure patients report improvements in skeletal muscle oxygen utilization, increased exercise capacity, muscle strength and endurance, improved diastolic function, reductions in inflammatory cytokines such as TNF-α and IL-6, improvement of symptoms and quality of life measurements, reduction in NYHA functional class, and reduction in hospital stays and mortality (Downing 2011). Most of these benefits were seen when exercising at moderate-high intensity (70-80% of peak heart rate).
Maintain Healthy Blood Sugar
Diabetes and insulin resistance are major risk factors for heart failure; diabetes not only increases the risk of heart failure, but it also worsens the outcome of patients with already existing heart failure (Hunt 2009). The diabetic heart is more susceptible to ischemic (low oxygen) injury, myocardial infarction, and oxidative damage (Ansley 2013). Metformin
, a standard oral treatment option for type 2 diabetes, is typically not utilized in diabetics with heart failure given the known risk for lactate accumulation and subsequent lactic acidosis in at-risk patients with compromised cardiac function; however, accumulating evidence suggests that metformin may offer important benefits for reducing
heart failure risk in select patients. For example, recent evidence suggests that metformin may reduce heart failure risk in diabetic patients, improve 2-year survival rates in those with heart failure, and have cardioprotective properties (Papanas 2012). As additional evidence accumulates, metformin may be an appropriate option for drug therapy in the context of reduced cardiac function in diabetic patients under close supervision of a qualified healthcare provider.