Journal article

Motivational Intervention to Reduce Cannabis Use in Young People with Psychosis: A Randomized Controlled Trial

Charles Bonsack, Silvia Gibellini Manetti, Jerome Favrod, Yves Montagrin, Jacques Besson, Pierre Bovet, Philippe Conus



BACKGROUND: Cannabis use has a negative impact on psychosis. Studies are needed to explore the efficacy of psychological interventions to reduce cannabis use in psychosis. Our aim is to study the efficacy of a specific motivational intervention on young cannabis users suffering from psychosis. METHODS: Participants (aged less than 35 years) were randomly assigned to treatment as usual (TAU) alone, or treatment as usual plus motivational intervention (MI + TAU). TAU was comprehensive and included case management, early intervention and mobile team when needed. Assessments were completed at baseline and at 3, 6 and 12 months follow-up. RESULTS: Sixty-two participants (32 TAU and 30 MI + TAU) w..

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Awarded by Swiss Research National Fund (FNS)

Funding Acknowledgements

Support for the study was provided by the Swiss Research National Fund (FNS), grant No. 3200BO-108454 to Dr. Charles Bonsack. Dr. Philippe Conus received support form the Leenaards Foundation in Lausanne, Switzerland. We thank clinicians and patients for their participation in the study. We thank the collaborators of the CEPIC (Clinical Epidemiology Center, Lausanne) and Gregoire Zimmermann for their statistical advice and Dr. Craig Macneil for his review of the paper.