Cannabis use and transition to psychosis in individuals at ultra-high risk: review and meta-analysis
- 16 November 2015
- journal article
- review article
- Published by Cambridge University Press (CUP) in Psychological Medicine
- Vol. 46 (4), 673-681
- https://doi.org/10.1017/s0033291715002329
Abstract
Previous research has established the relationship between cannabis use and psychotic disorders. Whether cannabis use is related to transition to psychosis in patients at ultra-high risk (UHR) for psychosis remains unclear. The present study aimed to review the existing evidence on the association between cannabis use and transition to psychosis in UHR samples. A search of PsychInfo, Embase and Medline was conducted from 1996 to August 2015. The search yielded 5559 potentially relevant articles that were selected on title and Subsequently 36 articles were screened on full text for eligibility. Two random-effects meta-analyses were performed. First, we compared transition rates to psychosis of UHR individuals with lifetime cannabis use with non-cannabis-using UHR individuals. Second, we compared transition rates of UHR individuals with a current DSM-IV cannabis abuse or dependence diagnosis with lifetime users and non-using UHR individuals. We found seven prospective studies reporting on lifetime cannabis use in UHR subjects (n = 1171). Of these studies, five also examined current cannabis abuse or dependence. Lifetime cannabis use was not significantly associated with transition to psychosis [odds ratio (OR) 1.14, 95% confidence interval (CI) 0.856–1.524, p = 0.37]. A second meta-analysis yielded an OR of 1.75 (95% CI 1.135–2.710, p = 0.01), indicating a significant association between current cannabis abuse or dependence and transition to psychosis. Our results show that cannabis use was only predictive of transition to psychosis in those who met criteria for cannabis abuse or dependence, tentatively suggesting a dose–response relationship between current cannabis use and transition to psychosis.Keywords
This publication has 44 references indexed in Scilit:
- Early interventions to prevent psychosis: systematic review and meta-analysisBMJ, 2013
- Pathways from Cannabis to Psychosis: A Review of the EvidenceAmerican Journal of Translational Research, 2013
- Diagnostic and Statistical Manual of Mental DisordersPsychiatry Research, 2011
- Temporal association of cannabis use with symptoms in individuals at clinical high risk for psychosisSchizophrenia Research, 2008
- Chronic Stress, Drug Use, and Vulnerability to AddictionAnnals of the New York Academy of Sciences, 2008
- Prediction of Psychosis in Youth at High Clinical RiskArchives of General Psychiatry, 2008
- Cannabis abuse and risk for psychosis in a prodromal samplePsychiatry Research, 2007
- North American Prodrome Longitudinal Study: A Collaborative Multisite Approach to Prodromal Schizophrenia ResearchSchizophrenia Bulletin, 2007
- Measuring inconsistency in meta-analysesBMJ, 2003
- Cannabis Use is Not Associated With the Development of Psychosis in an ‘Ultra’ High-Risk GroupAustralian & New Zealand Journal of Psychiatry, 2002