Prospective bidirectional associations of multidimensional sleep patterns with depressive symptoms: Findings from a...

Sleep health is multidimensional, yet existing research has largely examined isolated sleep characteristics, specific population groups, or only one direction of the sleep-depressive symptom relationship. As a result, the bidirectional associations between multidimensional sleep patterns and depressive symptoms remain insufficiently understood.

The study recruited 75,445 adults between July 2021 and December 2024 through the smart health management digital platform for primary cancer prevention (SmartHMDP-PCP) with 34,344 participants completed the follow-up survey. Sleep was assessed across eight dimensions-sleep midpoint, duration, pre-sleep activities, insomnia, sleep problems, daytime symptoms, medication use, and subjective quality-to construct a composite sleep score (healthy vs. unhealthy). Depressive symptoms were measured using the Self-Rating Depression Scale. Multivariate logistic regression estimated odds ratios (ORs) and 95% confidence intervals (CIs).

Healthy sleep was associated with reduced odds of incident depressive symptoms (OR, 95%CI: 0.62, 0.58-0.67) and increased likelihood of symptom remission (1.55, 1.41-1.69). Maintaining healthy sleep conferred the strongest protection against incident depressive symptoms (0.38, 0.35-0.42) and the greatest likelihood of remission (2.72, 2.42-3.06). In bidirectional analyses, absence of baseline depressive symptoms (0.60, 0.56-0.66), particularly when sustained over time (0.41, 0.37-0.46), was also negatively associated with subsequent deteriorations in sleep patterns, with effect sizes numerically comparable to those observed in the reverse direction.

Multidimensional sleep and depressive symptoms exhibit bidirectional associations of numerically similar magnitude. These findings underscore the importance of integrating sleep health promotion into mental health strategies and highlight the need for interventional and long-term longitudinal research to clarify causal pathways.