The association between habitual sleep duration and sleep quality in older adults according to health status.

BACKGROUND research on the association between habitual sleep duration and quality in older adults is scarce and has shown conflicting results. Moreover, no previous study has assessed the influence of health status on this association. OBJECTIVES to examine the association between habitual duration and quality of sleep in older adults, and to test if this association varies with health status, as approximated by self-rated health, quality-of-life and functional limitation. DESIGN cross-sectional study with data collected by telephone interview. SETTING community-based study. SUBJECTS a total of 1,567 community-dwelling individuals aged ≥68 years in Spain. METHODS poor sleep quality was ascertained through nighttime complaints (sleeping-pill consumption, difficulty falling asleep, awakening during the night and early awakening), and daytime complaints (feeling unrested in the morning and daytime sleepiness). The analyses were adjusted for the main confounders, and were stratified by health status (self-rated health, health-related quality-of-life and functional limitation). RESULTS when compared with those sleeping 7-8 h, those who slept ≤6 h were more likely to report difficulty falling asleep [odds ratio (OR) 3.51; 95% confidence interval (CI) 2.37-5.20], frequent awakening during the night (OR 1.97; 95% CI 1.42-2.75), early awakening in the morning (OR 2.78; 95% CI 2.02-3.82) and feeling unrested in the morning (OR 1.73; 95% CI 1.18-2.54). Moreover, those who slept ≥9 h were more likely to report daytime sleepiness (OR 1.68; 95% CI 1.17-2.42). In stratified analyses, these associations generally did not vary with health status. CONCLUSIONS in older adults, short sleep is associated with nighttime sleep complaints and feeling unrested in the morning, while long sleep is associated with daytime sleepiness.