The association between sleep onset time and depression among U.S. adults: a cross-sectional study from NHANES...

The link between sleep onset time and depression is not well understood. We aimed to investigate the association of sleep onset time with depression.

Data from the 2015 to March 2020 National Health and Nutrition Examination Survey were analyzed. Sleep onset time was categorized into five intervals: [22:00-23:00), [23:00-00:00), [00:00-01:00), [01:00-20:00), and [20:00-22:00). Depression was assessed using the Patient Health Questionnaire. Multivariate logistic regression and generalized linear regression analyses were conducted to evaluate the association of sleep onset time with depression.

The study sample consisted of 6991 adults (weighted mean age 45.6 years [SE, 0.5]; 49.5% female). Depression prevalence varied by sleep onset time intervals: 4.12% for [00:00-01:00), 5.94% for [01:00-20:00), 3.89% for [20:00-22:00), 1.98% for [22:00-23:00), and 3.26% for [23:00-00:00). After adjusting for sleep duration and other covariates, the odds ratios (ORs) for depressive symptoms were significantly greater at sleep onset time during [01:00-20:00) (OR, 2.39; 95% CI 1.20-4.74) and marginally higher at [20:00-22:00) (OR, 1.78; 95% CI 0.99-3.20) compared to the sleep onset time during [22:00-23:00). Higher PHQ-9 scores were associated with sleep onset time outside [22:00-23:00).

Sleep onset time between [22:00-23:00) was associated with the lowest odds of depression. This suggests new directions for depression research and interventions, emphasizing the importance of considering sleep onset time in mental health strategies.