Effects of omega-3 fatty acid on major cardiovascular outcomes: A systematic review and meta-analysis

BACKGROUND: The effects of omega-3 fatty acid on cardiovascular health obtained inconsistent results. A systematic review and meta-analysis were therefore conducted to assess the effects of omega-3 fatty acid supplementation for primary and secondary prevention strategies of major cardiovascular outcomes. METHODS: The databases of PubMed, Embase, and the Cochrane library were systematically searched from their inception until September 2020. Relative risks (RRs) with 95% confidence intervals were used to assess effect estimates by using the random-effects model. RESULTS: Twenty-eight randomized controlled trials involving 136,965 individuals were selected for the final meta-analysis. Omega-3 fatty acid was noted to be associated with a lower risk of major cardiovascular events (RR, 0.94; 95% CI, 0.89–1.00; P = .049) and cardiac death (RR, 0.92; 95% CI, 0.85–0.99; P = .022). However, no significant differences was noted between omega-3 fatty acid and the control for the risks of all-cause mortality (RR, 0.97; 95% CI, 0.92–1.03; P = .301), myocardial infarction (RR, 0.90; 95% CI, 0.80–1.01; P = .077), and stroke (RR, 1.02; 95% CI, 0.94–1.11; P = .694). CONCLUSIONS: Major cardiovascular events and cardiac death risks could be avoided with the use of omega-3 fatty acid. However, it has no significant effects on the risk of all-cause mortality, myocardial infarction, and stroke.