1132 FEAR OF SLEEP MODERATES THE RELATION BETWEEN INSOMNIA AND CANNABIS USE FREQUENCY AMONG VETERANS

Abstract Introduction: Insomnia has emerged as condition for which individuals are particularly apt to use cannabis. This has been demonstrated among medical cannabis users as well as recreational users with psychological conditions (e.g., anxiety). However, the reasons why certain individuals with insomnia are driven to use cannabis remain unknown. Given the extensive anecdotal and empirical literature pointing to the anxiolytic properties of some cannabis formulations, it is possible that individuals with insomnia use cannabis specifically to manage fear-related sleep processes. To examine this hypothesis, the present study aimed to determine whether fear of sleep serves to moderate the relation between insomnia severity and cannabis use frequency. Methods: Participants included 51 veterans (M = 46.63, SD = 16.35) with a cannabis use disorder (CUD), insomnia, and co-occurring psychopathology. Insomnia severity was measured with the Insomnia Severity Index (ISI), fear of sleep with the Fear of Sleep Index (FoSI), and cannabis, alcohol, and nicotine use frequency with the Timeline Followback Interview (TLFB). Results: Fear of sleep was examined as a moderator of the relation between insomnia severity and cannabis use frequency. Covariates included frequency of alcohol and nicotine use. An interaction between fear of sleep and insomnia severity was observed (β = 0.4, p = .01). Conditional effects indicated that insomnia severity was associated with greater cannabis use frequency among those with an elevated fear of sleep (β = 1.30, p = .01), but not those with less fear of sleep (β = -0.24, p = .61). Conclusion: Veterans with co-occurring insomnia and CUD appear to be at greatest risk for frequent cannabis use if their insomnia is rooted in a fear of sleeping. Findings highlight the importance of addressing (through exposure-based techniques) underlying sleep anxiety and fear as a means of curbing excessive cannabis use among individuals suffering from insomnia. Support (If Any): This project was funded by a VA Clinical Science Research & Development (CSR&D) Career Development Award-2 (CDA-2; CX001023) award to Dr. Babson.