Psychological interventions showed minimal benefit for people with both schizophrenia and substance use disorders
A JAMA Psychiatry meta-analysis of 35 trials found that current psychological and psychosocial interventions provided limited benefit for reducing symptoms and no effect on reducing substance use in people with co-occurring schizophrenia and substance use disorders, except for a small effect on nicotine use.
Quick Facts
What This Study Found
A very small effect favoring interventions was observed for overall symptoms (SMD -0.11, 95% CI -0.27 to 0.05, low confidence), mainly driven by nicotine studies. No difference was found for all types of substance use combined (SMD -0.01, 95% CI -0.21 to 0.18, moderate confidence). Alcohol, cannabis, amphetamines, and other stimulants separately showed no effect. Only nicotine showed a small treatment effect.
Key Numbers
35 RCTs, 4,136 participants (25.4% female, mean age 37.2 years). Overall symptoms: SMD -0.11 (low confidence). Substance use reduction: SMD -0.01 (moderate confidence). Alcohol, cannabis, amphetamines, stimulants: no significant effects. Only nicotine showed a small positive effect.
How They Did This
Systematic review and random-effect pairwise meta-analysis of 35 RCTs (4,136 participants). Cochrane Schizophrenia Group registry searched to January 2025. GRADE confidence ratings applied. No restrictions on substance type. Published in JAMA Psychiatry.
Why This Research Matters
About 42% of people with schizophrenia have co-occurring substance use disorders, yet they are frequently excluded from clinical trials. This comprehensive meta-analysis reveals that current evidence-based psychological treatments are essentially ineffective for this doubly burdened population, highlighting an urgent unmet treatment need.
The Bigger Picture
Published in JAMA Psychiatry, this meta-analysis carries considerable weight and effectively calls for a paradigm shift in how we treat this population. If standard psychological interventions do not work, new approaches, whether pharmacological, digital, integrated care models, or novel psychotherapies, are urgently needed.
What This Study Doesn't Tell Us
Meta-analysis is limited by the quality of included studies. Heterogeneity across intervention types, substances, and populations may mask effects in subgroups. The null finding for cannabis specifically may reflect limited studies targeting cannabis use in schizophrenia.
Questions This Raises
- ?What novel interventions might work for this population?
- ?Would integrated pharmacological and psychological approaches be more effective?
- ?Are there specific subgroups (by substance, symptom severity, or intervention type) where effects might emerge?
Trust & Context
- Key Stat:
- Current psychological interventions showed no effect on cannabis, alcohol, or stimulant use in people with schizophrenia
- Evidence Grade:
- Comprehensive meta-analysis published in JAMA Psychiatry with GRADE confidence ratings, representing the highest available evidence synthesis.
- Study Age:
- Published in 2026, with searches through January 2025.
- Original Title:
- Psychological and Psychosocial Interventions for People With Schizophrenia and Co-Occurring Substance Use Disorders: A Systematic Review and Meta-Analysis.
- Published In:
- JAMA psychiatry (2026)
- Authors:
- Salahuddin, Nurul Husna, Herlitzius, Emilia, Schütz, Alexandra, Siafis, Spyridon, Priller, Josef, Leucht, Stefan, Bighelli, Irene
- Database ID:
- RTHC-08598
Evidence Hierarchy
Combines results from multiple studies to find an overall pattern.
What do these levels mean? →Frequently Asked Questions
Do current treatments work for people with schizophrenia who also use substances?
This meta-analysis found that current psychological and psychosocial interventions had essentially no effect on substance use reduction in this population. Only nicotine use showed a small treatment response.
Why is this population so difficult to treat?
People with both schizophrenia and substance use disorders face compounding challenges: cognitive deficits that limit therapy engagement, self-medication patterns, social isolation, and treatments designed for either condition alone but not both together.
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Cite This Study
https://rethinkthc.com/research/RTHC-08598APA
Salahuddin, Nurul Husna; Herlitzius, Emilia; Schütz, Alexandra; Siafis, Spyridon; Priller, Josef; Leucht, Stefan; Bighelli, Irene. (2026). Psychological and Psychosocial Interventions for People With Schizophrenia and Co-Occurring Substance Use Disorders: A Systematic Review and Meta-Analysis.. JAMA psychiatry. https://doi.org/10.1001/jamapsychiatry.2025.4390
MLA
Salahuddin, Nurul Husna, et al. "Psychological and Psychosocial Interventions for People With Schizophrenia and Co-Occurring Substance Use Disorders: A Systematic Review and Meta-Analysis.." JAMA psychiatry, 2026. https://doi.org/10.1001/jamapsychiatry.2025.4390
RethinkTHC
RethinkTHC Research Database. "Psychological and Psychosocial Interventions for People With..." RTHC-08598. Retrieved from https://rethinkthc.com/research/salahuddin-2026-psychological-and-psychosocial-interventions
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.