Daan Kromhout, MPH, PhD, of the division of human nutrition at Wageningen University in the Netherlands, and colleagues randomly assigned 1,014 patients aged 60 to 80 years with diabetes to consume one of four margarines supplemented with daily recommended doses of omega-3 fatty acids: 400 mg eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) per day; 2 g alpha-linolenic acid (ALA) per day; a combination of the recommended daily doses of EPA, DHA and ALA; or placebo for 40 months. All patients had MI within the past 10 years.
On average, patients consumed 18.6 g margarine daily, according to the researchers, leading to additional intakes of 223 mg EPA, 149 mg DHA and 1.9 g ALA per day. During a median follow-up period of 40.7 months, 29 patients developed a ventricular arrhythmia-related event and 27 died of MI.
Data indicate that supplementation with any combination of the omega-3 fatty acids decreased ventricular arrhythmia-related events compared with placebo. However, patients assigned EPA and DHA plus ALA supplementation experienced the lowest incidence, with adjusted analyses suggesting that supplementation decreased these events by 84% vs. placebo (HR=0.16; 95% CI, 0.04-0.69). Results were similar for the combined endpoint of cardiac arrest and sudden death (HR=0.13; 95% CI, 0.02-1.09).
Although the researchers found no significant reductions in fatal MI among the treatment groups, after adjustment for potential confounders, combined supplementation of EPA and DHA plus ALA appeared to reduce the combined endpoint of ventricular arrhythmia-related events and fatal MI by 72% (HR=0.28; 95% CI, 0.11-0.71), the researchers said.
Kromhout said in a press release, that, "While more research is needed to definitively determine the role of these fatty acids in protecting people from ventricular arrhythmias, they seem to provide a benefit to the heart attack patients who also had diabetes." "This is the first study that showed a significant protective effect of omega-3 fatty acids in high-risk patients with diabetes who were on state-of-the-art drug treatment for their heart attack."
Kromhout D. Diabetes Care. 2011;34:2515-2520.