The American Heart Association has issued a science advisory on the effects of omega-3 polyunsaturated fatty acid (fish oil) supplementation and the prevention of clinical cardiovascular disease (CVD). The advisory reviews multiple randomized controlled trials (RCTs) and focuses on common indications for omega-3 polyunsaturated fatty acids (PUFAs) supplements related to the prevention of clinical CVD events. Prior recommendations for patients with existent coronary heart disease are updated and new recommendations made for patients with other clinical indications, including patients with diabetes mellitus and prediabetes and those with high risk for CVD, stroke, heart failure, and atrial fibrillation (AF). Among the recommendations:
- Treatment with omega-3 PUFA supplementation is reasonable for secondary prevention of CHD in patients with a recent CHD event such as a recent MI.
- Treatment with omega-3 PUFA supplements is reasonable for patients with existent heart failure without preserved left ventricular function to reduce mortality and hospitalizations.
- Treatment with omega-3 PUFA supplements is not recommended to prevent incident stroke among patients at high CVD risk and recurrent AF.
- Treatment for patients with diabetes mellitus and prediabetes to prevent CHD is not recommended, although there is a lack of consensus on the recommendation for patients at high CVD risk.
- Available evidence does not support the use of omega-3 PUFA supplements in the general population who are not at high CVD risk, including those with diabetes mellitus and prediabetes.
Siscovick DS, Barringer TA, Fretts AM, et al. Omega-3 polyunsaturated fatty acid (fish oil) supplementation and the prevention of clinical cardiovascular disease: A science advisory from the American Heart Association. [Published online ahead of print March 13, 2017]. Circulation. doi:10.1161/CIR.0000000000000482.
Observational data has demonstrated a decrease in cardiovascular events in individuals who consume fish containing omega–3 fatty acids.1 This has led to randomized trials that look at the effect of omega-3 PUFA supplements on cardiovascular outcomes. A potential mechanism by which omega-3 PUFA supplements may decrease outcomes is through stabilization of the myocardium, decreasing the likelihood of ischemia-induced ventricular fibrillation.2 This AHA statement refers to evidence-based recommendations about supplementing diet with fish oil, and it is important to recognize that it does not apply to eating fish or replacing meat with fish as a part of a healthy lifestyle. The bottom line in the AHA statement is that omega-3 PUFA may be beneficial for those with existent coronary disease and those with low-ejection fraction CHF. However, there is no evidence to support its use for primary prevention of coronary disease in either low or medium-risk individuals. Furthermore, most of the evidence suggested no effect even in high-risk individuals, though there was a lack of consensus on the panel in interpreting the data for these particular individuals. Therefore, consider its use in those with defined coronary artery disease or low ejection fraction CHF, but not for the primary prevention of coronary disease. —Neil Skolnik, MD
- Saravanan P, Davidson NC, Schmidt EB, Calder PC. Cardiovascular effects of marine omega-3 fatty acids. Lancet. 2010; 376:540-50. doi:10.1016/S0140-6736(10)60445-X.
- Mozaffarian D, Wu JH. Omega-3 fatty acids and cardiovascular disease: Effects on risk factors, molecular pathways, and clinical events. J Am Coll Cardiol. 2011;58:2047–2067. doi:10.1016/j. jacc.2011.06.063.