UC San Diego

OBJECTIVE: The purpose of this study was to determine whether sleep characteristics are associated with incidence of treated diabetes in postmenopausal individuals. METHODS: Postmenopausal participants ages 50-79 years reported sleep duration, sleep-disordered breathing, or insomnia at baseline and again in a subsample 3 years later. The primary outcome was self-reported new diagnosis of diabetes treated with oral drugs or insulin at any time after baseline. Multivariable Cox proportional hazards models were used. RESULTS: In 135,964 participants followed for 18.1 (± 6.3) years, there was a nonlinear association between sleep duration and risk of treated diabetes. Participants sleeping ≤5 hours at baseline had a 21% increased risk of diabetes compared with those sleeping 7 hours (adjusted hazard ratio [aHR] 1.21; 95% confidence interval [CI], 1.00-1.47). Those who slept for ≥9 hours had a nonsignificant 6% increased risk of diabetes compared with those sleeping 7 hours (aHR 1.06; 95% CI, 0.97-1.16). Participants whose sleep duration had decreased at 3 years had a 9% (aHR 1.09; 95% CI, 1.02-1.16) higher risk of diabetes than participants with unchanged sleep duration. Participants who reported increased sleep duration at 3 years had a risk of diabetes (HR 1.01; 95% CI, 0.95-1.08) similar to those with no sleep duration change. Participants at high risk of sleep-disordered breathing at baseline had a 31% higher risk of diabetes than those without (aHR 1.31; 95% CI, 1.26-1.37). No association was found between self-reported insomnia score and diabetes risk. CONCLUSIONS: Sleep-disordered breathing and short or long sleep duration were associated with higher diabetes risk in a postmenopausal population.