Written by

 

 

Paul D Thompson MD

In 2012, the American Heart Association’s (AHA) Scientific Statement on “Fish Consumption, Fish Oil, Omega-3 Fatty Acids, and Cardiovascular Disease” recommended that patients with established coronary heart disease (CHD) consume 1 g of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) per day, preferably from fatty fish. This recommendation was based on two large randomized controlled clinical trials (RCTs) in patients with established CHD. Multiple additional studies on fish fat or “marine-based polyunsaturated fatty acids” (PUFA) supplementation have been published over the past 15 years prompting an updated AHA Science Advisory.1 

The advisory panel reaffirmed that use of PUFA supplementation in patients with a recent CHD event such as an acute myocardial infarction again at a dose of one g of EPA/DHA per day. The panel also recommended treatment at the same dose in patients with heart failure and low ejection fraction (HFrEF), because this treatment reduces both SCD and readmissions in HRrEF patients. The panel did not recommend routine treatment with marine PUFAs in patients with diabetes or prediabetes and was divided on whether to recommend treatment for patients at high CHD risk. The panel did not find sufficient evidence to recommend marine PUFA supplementation to prevent new or recurrent stroke or atrial fibrillation. The estimated risk reduction in CHD patients approximated 10%. 

Marine PUFA supplementation appears very safe so there are few safety barriers to its use. Marine PUFAs appear to reduce the risk of sudden cardiac death (SCD) in both CHD and HFrEF patients, but may not alter the atherosclerotic process or reduce other CHD events such as acute MI. The update evaluated only omega-3 PUFA supplementation and not dietary intake of PUFAs since only supplements were evaluated in RCTs. The update did not evaluate plant-based omega-3 PUFA treatments because few RCT trials used plant-based PUFAs.  

These recommendations are extremely useful because patients often ask about fish oil supplements. Clinicians should remember that most over-the-counter (OTC) fish oil preparations contain 1 g of fish oil but only 300 mg of EPA/DHA. Consequently, 3 OTC capsules are required to deliver the recommended dose to CHD and HFrEF patients. Alternatively, clinicians can recommend prescription fish oil capsules, which generally contain 1 g of DHA and/or EPA. The advisory does not address the use of marine PUFA to reduce triglycerides, but marine PUFAs do reduce triglycerides in an increasing dose-dependent manner with a plateau of effect at 4 g daily of EPA/DHA.

References

1. 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. Circulation. 2017 Mar 13. doi: 10.1161/CIR.0000000000000482. [Epub ahead of print] http://circ.ahajournals.org/content/early/2017/03/13/CIR.0000000000000482.long