A pilot randomized controlled trial of an integrative psychotherapy incorporating an attachment-based approach for adolescents with cannabis use disorder (TIMCA)

Background Cannabis is the most used illicit substance among adolescents. Regular cannabis use is linked to cognitive and psychosocial difficulties. As no pharmacological treatment has proven effective, psychological interventions, including motivational interviewing (MI), cognitive-behavioral therapy (CBT), and family-based approaches, remain central. However, adolescent-specific evidence remains limited. TIMCA was developed as a ten-session integrative psychotherapy combining MI, CBT, and integrated attachment therapy. While family therapy may not be indicated for all adolescents, parental involvement remains important for the adolescent–parent relationship. TIMCA therefore combines individual and parent–adolescent sessions to address cannabis use alongside attachment-related and emotion-regulation processes. Objectives This pilot randomized controlled trial evaluated the feasibility and acceptability of TIMCA and explored changes over time in cannabis use and relational, emotional, anxiety/depressive, and treatment-adherence outcomes compared with treatment as usual (TAU). Methods Thirty-nine adolescents with cannabis use disorder were randomly assigned to TIMCA ( n = 19) or TAU ( n = 20) in two outpatient addiction services in the Paris metropolitan area. Cannabis use, attachment security, emotion regulation, anxiety, and depressive symptoms were assessed at baseline, mid-treatment, post-treatment, and 1-month follow-up using self-report measures and urine toxicology. Results TIMCA was feasible and acceptable, with high treatment adherence. Exploratory analyses showed significant within-group changes, including reductions in cannabis use, emotion dysregulation, and depressive symptoms, along with improved attachment security. In TAU, within-group changes did not reach statistical significance, and no significant between-group differences were detected. Conclusion TIMCA appears feasible and acceptable, supporting further evaluation in adequately powered trials with longer follow-up.