The Role of Cannabis Use in Anxiety and Related Disorders

Abstract

Objectives: The objective of this body of work was to begin addressing four questions about the association between cannabis use and anxiety and related disorders: 1. How is cannabis used?, 2. What are the motives for cannabis use?, 3. Is marijuana use temporally associated with anxiety symptoms?, 4. Does cannabis use impact anxiety and related disorder cognitive behavioural therapy (CBT) outcomes? Methods: Using self-report questionnaires, study 1 focused on understanding patterns of cannabis use in those seeking anxiety and related disorders services, while study 2 extended the findings from study 1 by examining motives for cannabis use in this population. Further, an experience sampling method was implemented for study 3 to explore whether clinical anxiety symptoms and marijuana use (i.e., dried cannabis material) were temporally associated. Using smartphone technology, marijuana use and anxiety data were captured over a 2-week period. Finally, study 4 investigated whether pre-treatment cannabis use impacted the change in anxiety and related disorder symptoms throughout CBT. Results: Individuals seeking anxiety and related disorder services often used cannabis, primarily via smoking joints. They used cannabis for various reasons but most commonly for coping and enhancement. Coping and expansion motives were significantly more common in frequent users compared to infrequent users. Further, earlier worry, but not anxiety or negative affect, was associated with increased likelihood of later marijuana use, however no long-term reduction in worry following marijuana use, suggesting that it is not an effective worry management strategy. Finally, frequent cannabis use was associated with dampened CBT outcomes compared to non-users, however their anxiety symptoms improved significantly from pre- to post-CBT. Conclusions: Collectively, results suggest that cannabis use plays an important role in anxiety and related disorders. The findings contribute to the understanding of the association between cannabis use and anxiety and related disorders, highlighting important clinical implications upon replication.