Posttraumatic stress symptoms and substance use among college students: Exploring interactions with sleep quality and...

Substance use is widely recognized as a negative outcome following traumatic events and is tied to symptoms of posttraumatic stress (PTS). Sleep quality may influence the PTS and substance use association, particularly among college students who are at risk for poor sleep. The purpose of the present study was to examine the moderating effect of sleep quality on the relationship between PTS and substance use in a cohort of college students, with an exploratory aim of examining potential differences by assigned sex. A screening survey was completed by 2,767 students enrolled in a larger RCT examining various brief college student alcohol reduction strategies. Results found a significant two-way interaction between PTS symptoms and subjective sleep quality on weekly number of drinks and peak drinking occasion, where the significant positive association between PTS symptoms to weekly drinks and peak drinking occasion was only found for those who reported poor sleep quality. A similar pattern emerged for the significant two-way interaction between PTS symptoms and subjective sleep quality on cannabis use frequency. A significant three-way interaction (i.e., PTS Symptoms × Poor Subjective Sleep Quality × Assigned Sex) indicated the two-way interaction between PTS symptoms and sleep quality for both weekly drinks and cannabis use frequency was stronger among male compared to female participants. Study findings suggest sleep quality is an important factor contributing to the relation between PTS symptom severity and substance use among college students. Strategies for assessing and improving sleep quality and PTS symptoms can be incorporated into prevention and intervention efforts targeting substance use related harm for college students.