Obesity is associated with incident atrial fibrillation independent of gender: A meta-analysis

Background: The prevalence of obesity is increasing among the general population. Obesity is associated with increased risk of several cardiovascular conditions, which in turn may increase the risk for atrial fibrillation (AF). We performed a meta-analysis of cohort studies that examined the effect of obesity on the incidence of AF. In addition, we examined the effect of obesity on the incidence of AF stratified by gender. Methods and results: We searched the MEDLINE and EMBASE databases for studies evaluating the effect of obesity on AF. Pooled risk ratios (RR) with 95% confidence intervals (CI) were calculated using a random effects model. Sixteen trials involving 587,372 subjects were included in the analysis. Obesity was defined as body mass index >30 kg/m(2). AF during follow-up developed in 5,751 of 91,031(6.3%) obese subjects and in 15,346 of 496,341(3.1%) nonobese subjects (RR = 1.51, 95% CI 1.35 to 1.68; P < 0.00001). Based on the pooled estimate across the studies, the effect of obesity on incident AF was similar in men (RR = 141, 95% 1.24 to 1.62; P < 0.00001) and women (RR =153, 95% CI 1.19 to 197; P < 0.00001). Conclusion: Obesity is associated with an increased risk of new-onset AF in susceptible individuals. This effect appears to be consistent in both genders. Further studies are warranted to examine the impact of weight loss interventions on the risk of developing AF.