- Objective. Marijuana is the most widely used illicit substance in the United States and in 2018 alone, an estimated 40.3 million adults reported using marijuana in the past year. As legalization for medical and recreational marijuana has been expanding, perceived risk of using marijuana has been steadily declining since the late 1980’s. This is concerning since growing research suggests that marijuana use is associated with adverse health and life outcomes, such as addiction, abnormal brain development, diminished life achievement, mental health issues, and cognitive impairments. Thus, determining factors that influence marijuana use and marijuana use-related problems is critical for understanding how to effectively implement prevention, intervention, and treatment efforts. Because research has proposed that difficulties in emotion regulation is a transdiagnostic risk factor for substance use and addiction, the investigation of emotion regulation capabilities in marijuana users is warranted. Furthermore, since prior studies suggest that stress may lead to greater marijuana use-related problems, additional research into how emotion regulation may affect these relationships is needed. Thus, the current study examines how emotion regulation moderates the association between stress and marijuana use in adults through an online survey.
Methods. 852 adults reporting any lifetime marijuana use completed an online survey through Qualtrics. Participants completed a brief demographic questionnaire including questions on age, biological sex, race/ethnicity, income, and education. Further, participants were asked to report their past 30-day use of marijuana, alcohol, nicotine, and illicit substances. To assess past month problematic marijuana use, participants completed the Marijuana Problem Scale (MPS). To assess difficulties in emotion regulation, participants completed the Difficulties in Emotion Regulation Scale (DERS). Participants completed the Perceived Stress Scale (PSS) and the Holmes-Rahe Life Stress Inventory (H-RLSI) to assess past month perceived stress and past year stressful life events, respectively. We investigated the association between scores on the DERS, PSS, and H-RLSI with scores on the MPS. Additionally, we conducted hierarchical multiple linear regression models to test whether emotion regulation, stress, and their interaction predicted problematic marijuana use.
Results. Our main results indicate scores on the DERS (r = .53, p < .001 ), PSS (r = .13, p < .001 ), and H-RLSI (r = .32 , p < .001) were significantly correlated with scores on the MPS. Additionally, difficulties in emotion regulation (B = .32, p < .001), stressful life events (B = .21, p <.001), and their interaction (B = .07, p = .003) were significant predictors of problematic marijuana use. Finally, difficulties in emotion regulation (B = .44, p < .001), perceived stress (B = -.18, p <.001), and their interaction (B = -.06, p = .04) were significant predictors of problematic marijuana use. Secondary analyses that reversed the predictor and outcome variables to test the opposite direction of relationships revealed that problematic marijuana use predicted more stressful life events (B = .29, p <.001) and less perceived stress (B = -.18, p <.001), but only at high levels of emotion dysregulation.
Conclusion. These findings indicate that when examined separately, greater difficulties in emotion regulation, experiencing more stressful life events in the past year, and experiencing more perceived stress in the past month are associated with greater problematic marijuana use in the past month. However, when examining the moderating role of emotion regulation, more stressful life events and less perceived stress predicted greater problematic marijuana use, and these associations were stronger at higher levels of emotion dysregulation. Finally, only among those with high levels of emotion dysregulation, greater problematic marijuana use predicted more stressful life events and less perceived stress, suggesting bidirectionality of effects. Overall, these results suggest that difficulties in emotion regulation and greater stress may be risk factors for developing problematic marijuana use, which could be possible targets for prevention, intervention, and treatment efforts. Due to possible bidirectionality of effects, future research would benefit from experimental or longitudinal designs to further elucidate the complex relationships between emotion regulation, stressful life events, perceived stress, and problematic marijuana use.