Physical activity and incidence of atrial fibrillation: a systematic review and meta-analysis.

Whether physical activity increases or decreases the risk of atrial fibrillation (AF) remains controversial. We conducted a systematic review and meta-analysis to evaluate the relationship between AF and extent of physical activity. We searched Medline and EMBASE in June 2014 for studies that reported on the associated risk of AF according to history of physical activity. Pooled risk ratios for AF were calculated using inverse variance random effects model, and heterogeneity assessed using I(2). Subgroup analysis was performed according to the nature of the physical activity, and the quality of the studies. We identified 19 relevant studies with a total of over half a million participants (n=511,503). The pooled analysis showed no association between intensive physical activity and AF (RR 1.00 95% CI 0.82-1.22, I(2)=73%, 8 studies, 152,925 participants) with no difference considering low and moderate to high risk of bias studies. Pooled analysis of studies reporting on increasing amount of time spent on physical activities did not show a significant association with AF (RR 0.95 95% CI 0.72-1.26, I(2)=84%, 4 studies, 112,784 participants). Studies of athletes or participants with a history of sports activity which were of poor methodology quality showed a borderline significant association with AF (pooled RR 1.98 95% CI 1.00-3.94, I(2)=59%, 6 studies, 1973 participants). In conclusion, we found no significant increase in AF with a higher level of physical activity. These findings support clinical guidelines encouraging patients to exercise as there is no evidence for harm associated with increased physical activity.