Sleep duration and risk of atrial fibrillation (from the Physicians' Health Study)

Although sleep quality and duration have been related to cardiovascular end points, 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 United States male physicians. Self-reported sleep duration was ascertained during a 2002 annual follow-up questionnaire. Incident AF was ascertained through annual follow-up questionnaires. Cox regression analysis was used to estimate the 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, the multivariate adjusted hazard ratio for AF was 1.06 (95% confidence interval 0.92 to 1.22), 1.0 (reference), and 1.13 (95% confidence interval 1.00 to 1.27) from the lowest to greatest category of sleep duration (p for trend = 0.26), respectively. In a secondary analysis, no evidence was seen of effect modification by adiposity (p for interaction = 0.69); however, prevalent sleep apnea modified the relation of sleep duration with AF (p for interaction = 0.01). From the greatest to the lowest category of sleep duration, the multivariate-adjusted hazard ratio for AF was 2.26 (95% confidence interval 1.26 to 4.05), 1.0 (reference), and 1.34 (95% confidence interval 0.73 to 2.46) for those with prevalent sleep apnea and 1.01 (95% confidence interval 0.87 to 1.16), 1.0 (reference), and 1.12 (95% confidence interval 0.99 to 1.27) for those without sleep apnea, respectively. Our data showed a modestly elevated risk of AF with long sleep duration among United States male physicians. Furthermore, a shorter sleep duration was associated with a greater risk of AF in those with prevalent sleep apnea.