Heterogeneity in sleep problems and suicide risk among adults with depression: a cross-sectional study.

In this paper, we investigated the relationship between different levels of sleep and the risk of suicide among depressive patients. The sample consisted of 301 adults with depression who were recruited from a hospital in Ningxia, China. The Pittsburgh Sleep Quality Index (PSQI) and the Self-Rating Depression Scale (SDS) were applied to evaluate the quality of sleep and the degree of depression. The Suicidal Risk Factor Assessment Form evaluated suicide risk. A Latent Class Analysis (LCA) has been performed with MPLUS 7.0 to investigate the most probable category of the PSQI sub-scales. Multivariate Logistic Regression was applied to analyse the relation between Sleep Quality and Suicide Hazard in Adult Depressive Patients. Classes identified were "Global sleep impairment", "Poor sleep quality", "Short sleep duration" and "Good sleep quality." Patients with poor overall sleep quality and clear daytime dysfunction had a higher risk of suicide than those with good sleep quality. The results are helpful in understanding the relationship between the variability of sleep patterns and the risk of suicide among depressed people, and it is suggested that some sleep variables may have a higher predictive value than others. The results will provide guidance on how to improve and implement therapy for depressive disorders in adults, and to lower suicidal rates.