Omega-3 polyunsaturated fatty acid supplementation in the prevention of cardiovascular disease

Introduction: Omega-3 polyunsaturated fatty acids (PUFAs) have purported protective cardiovascular (CV) effects. We sought to assess the evidence available for the use of omega-3 PUFAs for the prevention of cardiovascular disease (CVD). Methods: A systematic literature search was conducted using MEDLINE and EMBASE from 1999 to 2015. Placebo-controlled, randomized controlled trials (RCTs) that enrolled over 1000 patients with follow-up greater than 1 year and meta-analyses of RCTs were included. Results: Eight RCTs and 2 meta-analyses were included. In patients with preexisting CVD, only 1 of 5 included RCTs demonstrated a reduction in CV events with omega-3 PUFAs; however, the effect size was minimal, and the study was limited by an open-label design and lack of placebo control. Two meta-analyses concluded omega-3 PUFAs do not reduce CV events in addition to standard, evidence-based therapy in patients after myocardial infarction. Of the 3 predominantly primary prevention RCTs, only 1 demonstrated a minor reduction in major coronary events; however, it was also an open-label study. Furthermore, the safety of omega-3 PUFAs should be considered. While data from RCTs have not demonstrated serious safety concerns, omega-3 PUFAs can increase the risk of bleeding and may interact with other medications that affect hemostasis, such as antiplatelet agents and warfarin. Discussion and Conclusion: There is currently a lack of evidence to support the routine use of omega-3 PUFAs in the primary and secondary prevention of CVD. Pharmacists are ideally situated to engage patients in the discussion of the lack of benefit and possible risk of omega-3 PUFA supplements.