MONDAY, May 24, 2021 (HealthDay News) -- High levels of eicosapentaenoic acid (EPA), an omega-3 (ω-3) fatty acid, are no benefit to patients at high risk for cardiovascular events, according to a study published online May 16 in JAMA Cardiology to coincide with the annual meeting of the American College of Cardiology, held virtually from May 15 to 17.
Steven E. Nissen, M.D., from the Cleveland Clinic, and colleagues randomly assigned 13,078 patients at high cardiovascular risk with elevated triglyceride levels and low levels of high-density lipoprotein cholesterol to receive 4 g daily of ω-3 carboxylic acid or an inert comparator, corn oil. Plasma levels of EPA or docosahexaenoic acid (DHA) were assessed at baseline and after 12 months.
The researchers found that the median plasma levels at 12 months in ω-3 carboxylic acid patients were 89 μg/mL for EPA and 91 μg/mL for DHA, with top tertile levels of 151 and 118 μg/mL, respectively. The adjusted hazard ratios for cardiovascular events with the highest tertile of achieved plasma levels were 0.98 (95 percent confidence interval, 0.83 to 1.16; P = 0.81) for EPA and 1.02 (95 percent confidence interval, 0.86 to 1.20; P = 0.85) for DHA compared with corn oil. Results were similar in sensitivity analyses based on changes in plasma and red blood cell levels of EPA and DHA as well as for primary and secondary prevention subgroups.
"Our analysis shows no evidence that a high EPA level produces cardiovascular benefit," Nissen said in a statement. "Previous studies have found that for those with very high triglycerides, fish oil supplements or icosapent ethyl help in lowering them. However, based on the current evidence, there is no reduction in overall cardiovascular risk for patients."
Several authors disclosed financial ties to pharmaceutical companies, including AstraZeneca, which sponsored the study.