International Omega-3 Learning and Education Consortium for Health and Medicine

The long-chain omega-3 fatty acid EPA (eicosapentaenoic acid 20:5n-3) has recently been investigated for its effects on cardiovascular health. Specifically, the effects of EPA on major coronary events were investigated in a large Japanese study known as the JELIS trial (Japan EPA Lipid Intervention Study). Conducted over a 5-year period, the JELIS trial was designed to test the hypothesis that long-term supplementation with 1800 mg/day EPA would prevent major coronary events in hypercholesterolemic patients in Japan ¹. This large trial included over 18,000 individuals ² (15,000 without existing coronary artery disease, and 3,645 with existing coronary artery disease), all between the ages of 40 and 75. Study participants were all placed on statin therapy and then randomized in an open-label, endpoint-blinded manner to either the EPA 1800 mg/day group or the control group. The primary endpoint was any major cardiovascular event (sudden death, fatal or non-fatal myocardial infarction, unstable angina, angioplasty, or coronary artery bypass surgery).

After a mean follow-up of 4.6 years, major cardiovascular events occurred in 262 (2.8%) individuals in the EPA group, versus 324 individuals (3.5%) in the control group - a 19% relative reduction in major coronary events ¹. The incremental effects of EPA on cardiovascular events were also analyzed ². In patients with a history of prior coronary heart disease, events were reduced 19% by EPA versus no treatment (event rates of 8.7% versus 10.7%). In 1,050 subjects with a history of prior myocardial infarction, the risk of subsequent coronary events was reduced in the EPA group by 27%. These results indicate that 1800 mg/day EPA supplementation achieved both primary prevention and secondary prevention of coronary events in Japanese hypercholesterolemic patients. The greatest risk reduction was noted in those individuals with triglyceride levels > 150 mg/dl and high density lipoprotein (HDL) cholesterol levels < 40 mg/dl ³. In this sub-group, EPA supplementation reduced cardiovascular events by 53%.

It should be noted that the JELIS trial population was exclusively Japanese, and this population exhibits a high background consumption of fish. The results of the JELIS trial are consistent with those from observational studies in Japanese populations which indicate a lower risk of non-fatal coronary events with high intake of fish ⁴. The JELIS trial was the first to examine the particular effects of EPA on coronary events. These results should inspire future studies to investigate the effects of EPA on major coronary events in other populations.

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