Effect of Omega-3 Dosage on Cardiovascular Outcomes : An Updated Meta-Analysis and Meta-Regression of Interventional Trials

Objectives:To quantify the effect of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids oncardiovascular disease (CVD) prevention and the effect of dosage. Methods:This study is designed as a random effects meta-analysis and meta-regression of ran-domized control trials with EPA/DHA supplementation. This is an update and expanded analysis ofa previously published meta-analysis which covers all randomized control trials with EPA/DHAinterventions and cardiovascular outcomes published before August 2019. The outcomes includedare myocardial infarction (MI), coronary heart disease (CHD) events, CVDevents (a composite ofMI, angina, stroke, heart failure, peripheral arterial disease, sudden death, and non-scheduledcardiovascular surgical interventions), CHD mortality and fatal MI. The strength of evidence wasassessed using the Grading of Recommendations Assessment, Development, and Evaluationframework. Results:A total of 40 studies with a combined 135,267 participants were included. Supplementationwas associated with reduced risk of MI (relative risk [RR], 0.87; 95% CI, 0.80 to 0.96), high certaintynumber needed to treat (NNT) of 272; CHD events (RR, 0.90; 95% CI, 0.84 to 0.97), high certaintyNNT of 192; fatal MI (RR, 0.65; 95% CI, 0.46 to 0.91]), moderate certainty NNT¼128; and CHDmortality (RR, 0.91; 95% CI, 0.85 to 0.98), low certainty NNT¼431, but not CVD events (RR, 0.95;95% CI, 0.90 to 1.00). The effect is dose dependent for CVD events and MI. Conclusion:Cardiovascular disease remains the leading cause of death worldwide. Supplementationwith EPA and DHA is an effective lifestyle strategy for CVD prevention, and the protective effectprobably increases with dosage.