Abstract P254: Daytime Napping is Associated With Incident Stroke in Community

Abstract

Introduction: There are conflicting reports regarding whether daytime napping is a risk factor for cardiovascular events. The purpose of this study was to investigate the relationship between daytime napping and incident stroke within a community-based cohort study. Hypothesis: We assessed the hypothesis that the duration and the frequency of daytime napping may be associated with incident stroke. Methods: Participants without previous stroke were enrolled in the present prospective study from the Sleep Heart Health Study (registration number, NCT00005275). Daytime napping were assessed with a self-reported Sleep Habits Questionnaire. Duration of daytime napping was divided into the following categories: no naps, 0-30 min, 31-60 min, or >60 min. Frequency of naps were categorised as: no naps, 1-2 times/week, 3-4 times/week, 5-6 times/week, or daily. After combining nap duration and frequency, participants were further divided into groups with regular long naps (≥5 times per week and >30 min), regular short naps (≥5 times per week and ≤30 min), irregular naps or no naps. Subsequently, participants were followed up until the first stroke occurred between the date of the completed questionnaire and the final censoring date. Cox regression analysis was used to estimate the relationship between daytime napping and incident stroke. Results: The present study enrolled 4757 participants, of which 220 participants (4.6%) experienced incident stroke during an average follow-up of 10.6 years. There was a higher rate of stroke among participants taking longer and more frequent naps than others. Multivariate Cox regression analysis indicated that, when compared with participants with no naps, those with a nap duration of ≥60 min or of 31-60 min had a higher risk of stroke (HR, 2.182; 95% CI, 1.443-3.301; HR, 1.594; 95% CI, 1.003-2.531, respectively). Moreover, there was an increased risk of stroke among participants taking daily daytime naps (HR, 1.563; 95% CI, 1.059-2.307) or napping 5-6 times per week (HR, 1.548; 95% CI, 1.026-2.335) than those with no naps. And after combining nap duration and frequency, regular long naps and regular short naps were also associated with higher risk of incident stroke (HR, 1.903; 95% CI, 1.182-3.065; HR, 1.451; 95% CI, 1.010-2.084, respectively). Conclusions: In conclusion, daytime napping of long duration and high frequency may increase the risk of incident stroke in community. Modification of sleep habits may improve the life quality among those elderly community-based population.