Sleep quality and its associated factors among community-dwelling patients with severe mental disorders in Minhang District, Shanghai: A cross-sectional study.

Background

Sleep disturbances are common in severe mental disorders (SMD), but community-based epidemiological data in China are scarce. This study examined the prevalence and correlates of poor sleep quality and tested the indirect pathways of psychological distress in the association between social support and sleep.

Methods

Using 2022 baseline data from a community survey in Shanghai, we included 3797 SMD patients (mean age 54.9 years; 51.6% female; 64.1% schizophrenia-spectrum). Sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI; poor defined as >5), social support with PSSS, anxiety with GAD-7, and depression with PHQ-9. Hierarchical multivariable regression, bootstrap mediation (5000 resamples), and K-means clustering were applied.

Results

Mean PSQI was 5.14, and 39.3% had poor sleep. The full model explained 27.8% of variance. PHQ-9 was the strongest independent correlate of poor sleep. Comorbidity (OR = 1.48, 95% CI 1.23-1.77) and lower household income increased risk, whereas no hospitalization history was associated with lower odds of poor sleep. The indirect effect via depression accounted for 81.4% of the total association between social support and sleep, while that via anxiety accounted for 57.8%; the PSSS×PHQ-9 interaction was significant. Three sleep phenotypes were identified: mild (36.1%, mean PSQI 2.7), moderate (43.4%, mean 4.8), and severe (20.5%, mean 10.2), with PHQ-9 as the strongest discriminator.

Conclusions

Poor sleep is highly prevalent in community SMD patients. Depression appears central in the indirect pathway from social support to sleep. Integrating depression management, social support enhancement, and phenotype-based stratification warrants further investigation to improve sleep.