Gencer B, Djousse L, Al-Ramady OT, et al. - An increased risk of atrial fibrillation (AF) resulted from marine omega-3 supplementation in randomized controlled trials (RCTs) examining cardiovascular outcomes. The risk seemed to be greater in trials examining >1g/d.

• RCTs of cardiovascular outcomes of marine omega-3 fatty acids were included if they mentioned results for AF, had a minimum sample size of 500 patients and a median follow-up of at least one year.

• A meta-analysis of 7 trials with 81,210 patients was performed.

• Marine omega-3 fatty acid supplementation was related to an elevated risk of AF (n=2,905; hazard ratio HR: 1.25).

• A greater HR was reported in the trials testing >1g/d (HR 1.49) relative to those testing ≤1 g/d (HR 1.12).

• Metaregression showed an increase in HR for AF per 1 gr increase of omega-3 fatty acids dosage (HR 1.11).