Explaining alcohol use and suicide risk: a moderated mediation model involving insomnia symptoms and gender.

STUDY OBJECTIVES The purpose of the study was to examine whether insomnia symptoms and nightmares mediated the relation between alcohol use and suicide risk. Further, we examined whether this mediation was moderated by gender. DESIGN The study consisted of questionnaires administered online examining insomnia symptoms, nightmares, alcohol use, and suicide risk. SETTING University. PATIENTS OR PARTICIPANTS 375 undergraduate students at a large, public university in the southeastern United States. INTERVENTIONS N/A. MEASUREMENTS AND RESULTS Results indicated that insomnia symptoms significantly mediated the relation between alcohol use and suicide risk; however, this mediation was moderated by gender. For women, there was both a direct effect of alcohol use on suicide risk as well as an indirect effect of alcohol use through insomnia symptoms increasing suicide risk. For men, there was no direct effect of alcohol use on suicide risk, but there was a significant indirect effect of alcohol use increasing suicide risk through insomnia symptoms. Nightmares were not related to alcohol use, and the association between nightmares and suicide risk was found to be independent of alcohol use. CONCLUSIONS Insomnia symptoms are an important factor in explaining the mechanism by which alcohol use increases suicide risk.