Introduction:
Patients who self-report short sleep duration are thought to have a higher risk of atrial fibrillation (AF), but objective data are lacking and it is not clear if this association is independent of sleep apnea. In this cross-sectional investigation, we evaluated the association between objectively measured sleep duration and AF in patients undergoing diagnostic sleep study.
Methods:
We evaluated all 30,572 patients who underwent in-laboratory diagnostic sleep study at one of six centers within the University of Pittsburgh Medical Center system from March 1999 to December 2015. Total sleep time (TST), apnea hypopnea index (AHI), percent sleep with oxygen saturation < 90% (Per90), and cardiac rhythm on overnight EKG were extracted from sleep study reports using automated algorithms. Multivariable linear regression was used to model TST as a function of rhythm accounting for age, sex, body mass index (BMI) and sleep apnea severity using both AHI and Per90. We also performed a sensitivity analysis using patients whose AF status was confirmed by an inpatient or outpatient ICD-9 code at any point up to one day prior to the date of the sleep study.
Results:
The cohort was 52.0% female, aged 50.8±14.6 years (mean ± std dev), had a BMI of 33.7 ± 8.7 kg/m
2
, and an AHI of 17.4 ± 22.6 events/hr. Of the 30,572 patients, 369 (1.2%) had AF, 60 had a paced rhythm, 28,844 were in sinus, and 1299 had unclear rhythm. After adjusting for age and sex, TST was lower by 34 minutes (95% confidence interval, 26-42) in patients in AF compared to those in sinus rhythm. After further adjustment for BMI, AHI and Per90, TST was 28 minutes (18-38) lower for those in AF. The TST difference between patients in AF and sinus was primarily related to reduction in stage 2 non-REM sleep; AF patients had 32 minutes (22-41) less stage 2 sleep after adjustment. In a sensitivity analysis limited to 268 AF subjects with at least one AF diagnostic code and 26,239 sinus rhythm subjects without an AF diagnostic code, TST was 29 minutes (17-41) shorter in AF patients after adjustment.
Conclusion:
After accounting for differences in demographics and sleep apnea severity, patients with AF sleep about half an hour less on objective assessment. Our findings support an association between short sleep and AF. Future prospective studies are needed to determine if short sleep may be a novel mechanism for the development of AF.
Associations of allostatic load with sleep apnea, insomnia, short sleep duration, and other sleep disturbances: findings from the National Health and Nutrition Examination Survey 2005 to 2008
