Meta-analysis results indicate protective effect for omega-3 against heart attack and sudden death
Tuesday, August 27, 2013. The results of a meta-analysis reported in the August 2013 issue of the journal Atherosclerosis Supplements add evidence to the benefit of omega-3 polyunsaturated fatty acid supplementation for the prevention of cardiac death, sudden death and heart attack in cardiovascular disease patients.
For their analysis, researchers in Milan selected 11 randomized, double-blinded trials involving a total of 15,348 men and women with a history of cardiovascular disease. Participants received a placebo or at least one gram omega-3 fatty acids per day. Eight hundred twenty-five patients died over the course of the trials, which ranged in length from one to five years.
The risks of cardiac death and sudden death were significantly reduced by 32% and 33% among subjects who received the supplements in comparison with the placebo group. Furthermore, the risk of heart attack was reduced by 25% among those who received omega-3, and there was an 11% lower risk of all-cause mortality (although the latter did not reach statistical significance).
Omega-3 fatty acid supplements may provide several cardiovascular benefits, including protection against arrhythmia, reduction of blood clots, stabilization of plaque, vasodilation, and lipid reduction. The authors suggest that the lack of effect observed in some trials could be due to the concurrent use of statin drugs or other medications by the participants.
"We chose to include randomized, double-blind, placebo controlled trials investigating the effect of omega-3 fatty acid administration to patients with existing cardiovascular disease (the group most likely to benefit from their use), through administration of sufficiently high doses, and for time windows sufficiently long to manifest their cardiovascular preventive action," Manuela Casula and her associates write.
"Our results supply evidence that long-term effect of high dose omega-3 fatty acid supplementation may be beneficial for the onset of cardiac death, sudden death and myocardial infarction among patients with a history of cardiovascular disease," they conclude.