Cannabis use and trauma-focused treatment for co-occurring posttraumatic stress disorder and substance use disorders: A meta-analysis of individual patient data
Melanie L Hill 1, Alexander C Kline 2, Tanya C Saraiya 3, Jordan Gette 4, Lesia M Ruglass 5, Sonya B Norman 6, Sudie E Back 7, Lissette M Saavedra 8, Denise A Hien 4, Antonio A Morgan-López 8
- 1Department of Psychiatry, University of California San Diego, San Diego, CA, USA. Electronic address: mlhill8@asu.edu.
- 2Veterans Affairs San Diego Healthcare System, San Diego, CA, USA.
- 3Center of Alcohol & Substance Use Studies, Rutgers University, Piscataway, NJ, USA; Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA.
- 4Center of Alcohol & Substance Use Studies, Rutgers University, Piscataway, NJ, USA.
- 5Center of Alcohol & Substance Use Studies, Rutgers University, Piscataway, NJ, USA; Department of Psychology, The City College of New York, New York, NY, USA.
- 6Department of Psychiatry, University of California San Diego, San Diego, CA, USA; Veterans Affairs San Diego Healthcare System, San Diego, CA, USA; National Center for PTSD, Executive Division, White River Junction, VT, USA.
- 7Department of Psychiatry & Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA; Ralph H. Johnson Veterans Affairs Healthcare System, Charleston, SC, USA.
- 8RTI International, Research Triangle Park, NC, USA.
Affiliationer
High rates of cannabis use among people with posttraumatic stress disorder (PTSD) have raised questions about the efficacy of evidence-based PTSD treatments for individuals reporting cannabis use, particularly those with co-occurring alcohol or other substance use disorders (SUDs). Using a subset of four randomized clinical trials (RCTs) included in Project Harmony, an individual patient meta-analysis of 36 RCTs (total N = 4046) of treatments for co-occurring PTSD+SUD, we examined differences in trauma-focused (TF) and non-trauma-focused (non-TF) treatment outcomes for individuals who did and did not endorse baseline cannabis use (N = 410; 70% male; 33.2% endorsed cannabis use). Propensity score-weighted mixed effects modeling evaluated main and interactive effects of treatment assignment (TF versus non-TF) and baseline cannabis use (yes/no) on attendance rates and within-treatment changes in PTSD, alcohol, and non-cannabis drug use severity. Results revealed significant improvements across outcomes among participants in all conditions, with larger PTSD symptom reductions but lower attendance among individuals receiving TF versus non-TF treatment in both cannabis groups. Participants achieved similar reductions in alcohol and drug use across all conditions. TF outperformed non-TF treatments regardless of recent cannabis use, underscoring the importance of reducing barriers to accessing TF treatments for individuals reporting cannabis use.
Keywords: Attendance; Cannabis; Marijuana; Posttraumatic stress disorder; Substance use.
