Do omega-3 fatty acids increase risk of atrial fibrillation?

To summarize the findings from recent observational follow-up studies and randomized trials of plant- and marine omega-3 fatty acids on the risk of atrial fibrillation (AF).

Recent randomized cardiovascular outcome trials have indicated that supplements with marine omega-3 fatty acids may be associated with a higher risk of AF, and a meta-analysis has suggested that marine omega-3 fatty acid supplements were associated with a 25% higher relative risk of AF. Also, a recent large observational study reported a modest higher risk of AF in habitual users of marine omega-3 fatty acid supplements. However, recent observational biomarker studies of circulating and adipose tissue content of marine omega-3 fatty acids have in contrast reported a lower risk of AF. Very limited knowledge exists on the role of plant-derived omega-3 fatty acids and AF.

Marine omega-3 fatty acid supplements may increase the risk of AF, whereas biomarkers reflecting consumption of marine omega-3 fatty acids have been linked to a lower risk of AF. Clinicians should inform patients that marine omega-3 fatty acid supplement may increase AF risk, and this should be taking into account when discussing pros and cons of taking supplements with marine omega-3 fatty acids.