Cross-Sectional Associations of Insomnia, Social Dysfunction, Suicidality, and Depressive Symptoms in Rural Adults...

Insomnia, social dysfunction, suicidality, and depressive symptoms commonly co-occur in schizophrenia. Their joint cross-sectional associations and potential sex differences among rural adults with schizophrenia remain unclear.

This multicenter cross-sectional study included 931 rural adults with schizophrenia in Chaohu, China. Depressive symptoms, insomnia severity, social dysfunction, and suicidality were assessed using the Patient Health Questionnaire-9, Insomnia Severity Index, Social Disability Screening Schedule, and a composite suicidality score, respectively. Sex-stratified logistic regression and exploratory indirect-association analyses with 5,000 bootstrap resamples were conducted. A sensitivity analysis used a non-overlapping Patient Health Questionnaire-7 score excluding the sleep and suicidality items.

Of 931 participants, 457 were male and 474 were female. Female participants had higher depressive-symptom, insomnia, suicidality, and social-dysfunction scores than male participants (all P≤0.005). In both sex-stratified models, higher insomnia, suicidality, and social-dysfunction scores were associated with greater odds of at least mild depressive symptoms. In the exploratory model, insomnia severity was directly associated with depressive-symptom score (b=0.388, 95% bootstrap confidence interval [CI], 0.345-0.431). Indirect associations via social dysfunction (0.042, 95% CI, 0.028-0.057) and suicidality (0.038, 95% CI, 0.021-0.058) were supported, whereas the serial indirect association was not (0.002, 95% CI, -0.0001 to 0.005). Sex did not moderate the indirect associations.

Women reported higher symptom and social-dysfunction scores than men, but sex did not moderate the estimated indirect associations. Insomnia, social dysfunction, suicidality, and depressive symptoms formed a clinically relevant cross-sectional pattern; however, temporal ordering and causality cannot be inferred. Longitudinal studies with non-overlapping measures and broader clinical covariates are needed.