While sleep quality and duration have been related to cardiovascular endpoints, little is known about the association between sleep duration and incident atrial fibrillation (AF). Hence, we prospectively examined the association between sleep duration and incident AF in a cohort of 18,755 US male physicians. Self-reported sleep duration was ascertained during 2002 annual follow-up questionnaire. Incident AF was ascertained through yearly follow-up questionnaires. Cox regression was used to estimate relative risks of AF. The average age at baseline was 67.7 (+8.6) years. During a mean follow up of 6.9 (±2.1) years, 1,468 cases of AF occurred. Using 7 hours of sleep as the reference group, multivariable adjusted hazard ratios (95% CI) for AF were 1.06 (0.92–1.22), 1.0 (ref), and 1.13 (1.00–1.27) from the lowest to the highest category of sleep duration (p for trend 0.26), respectively. In a secondary analysis, there was no evidence of effect modification by adiposity (p interaction =0.69); however, prevalent sleep apnea modified the relation of sleep duration with AF (p interaction =0.01): from the highest to the lowest category of sleep duration, multivariable adjusted hazard ratios (95% CI) for AF were 2.26 (1.26–4.05), 1.0 (ref), and 1.34 (0.73–2.46) for those with prevalent sleep apnea and 1.01 (0.87–1.16), 1.0 (ref), and 1.12 (0.99–1.27) for those without sleep apnea, respectively. Our data showed a modestly elevated risk of AF with long sleep duration among US male physicians. Furthermore, shorter sleep duration was associated with a higher risk of AF in people with prevalent sleep apnea.

Background-Although previous studies have suggested that competitive athletes have a higher risk of atrial fibrillation than the general population, limited and inconsistent data are available on the association between regular physical activity and the risk of atrial fibrillation. Methods and Results-A systematic, comprehensive literature search was performed using MEDLINE, EMBASE, and COCHRANE until 2011. Extracted data from the eligible studies were meta-analyzed using fixed effects model. Four studies, which included 95 526 subjects, were eligible for meta-analysis. For all of the studies included, the extreme groups (ie, maximum versus minimal amount of physical activity) were used for the current analyses. The total number of participants belonging to the extreme groups was 43 672. The pooled odds ratio (95% confidence interval) for atrial fibrillation among regular exercisers was 1.08 (0.97-1.21). Conclusions-Our data do not support a statistically significant association between regular physical activity and increased incidence of atrial fibrillation. (Circ Arrhythm Electrophysiol. 2013;6:252-256.)