Effectiveness and clinical predictors of a virtual based combined cognitive behavioral and motivational enhancement group therapy for adults with cannabis use disorder.

BACKGROUND

Cannabis use has increased in recent years, while perceptions of harm have declined. Cognitive behavioural therapy (CBT), motivational enhancement therapy (MET), and their combinations (CBT-MET) are evidence-based interventions for CUD, though their effectiveness when delivered virtually is underexplored. This study evaluated the clinical efficacy of a virtual 12-week group-based CBT-MET program in individuals with CUD and examined baseline predictors of treatment response.

METHODS

A retrospective analysis was conducted on 116 adults enrolled in a virtual group-based CBT-MET program between 2020 and 2023. Participants completed weekly self-report assessments of cannabis use and biweekly assessments of depression (PHQ-9) and anxiety (GAD-7). Cannabis craving (MCQ) and a measure of problematic cannabis use (CUDIT) were assessed at baseline and post-treatment. Wilcoxon signed-rank tests evaluated changes among completers (≥ 75 % attendance), and linear mixed models identified baseline predictors of change over time.

RESULTS

Of the 116 participants, 79 (68 %) completed the program, indicating high retention. Among completers, significant reductions were observed in cannabis use frequency (p < 0.01), quantity (p < 0.01), craving (p < 0.01), depression (p < 0.01), and anxiety (p = 0.02). Higher baseline cannabis use predicted greater reductions in cannabis frequency and quantity, while higher self-efficacy predicted lower cannabis use frequency across treatment. Individuals with co-occurring substance use disorders other than tobacco demonstrated smaller reductions in cannabis quantity.

CONCLUSION

Virtual CBT-MET was feasible and led to significant reductions in cannabis use and psychiatric symptoms among individuals with CUD. Baseline cannabis use patterns and self-efficacy were key predictors of reduction in cannabis use, highlighting the need for personalized approaches in future interventions.