A systematic review including 10 studies with a total of 14727 subjects was abstracted in DARE. Daily intake of omega-3 fatty acids for a mean duration of 37 months decreased all cause mortality by 16% (RR 0.84, 95% CI 0.76 to 0.94, 6 studies) and the risk of death due to MI by 24% (RR 0.76, 95%CI 0.66 to 0.88, 4 studies). There were no statistically significant differences between the fish oil and placebo groups for any of the other outcomes: nonfatal MI (RR 1.03, 95% CI 0.87 to 1.19, 7 studies), nonfatal stroke (RR 1.36, 95% CI 0.87 to 2.29, 3 studies), and angina pectoris (RR 1.03, 95% CI 0.85 to 1.20, 7 studies). There is absence of data in patients receiving statins.
Comment: The quality of evidence downgraded by indirectness (absence of data in patients receiving statins).