Persistent cannabis use predicted worse outcomes in young adults with first-episode psychosis

Of 938 first-episode psychosis patients in Coordinated Specialty Care, 38.8% used cannabis at admission and 32.8% had persistent use at 1 year. Persistent users were more likely male, had worse baseline symptoms, more suicidality, violent ideation, and legal trouble. At 1 year, persistent users maintained worse symptoms than non-users, while those who reduced use showed significant symptom improvement.

Longitudinal analysis of 938 first-episode psychosis patients enrolled in US Coordinated Specialty Care programs for at least 1 year, categorized into no use, reduced use, and persistent cannabis use groups.

One-third of first-episode psychosis patients continued using cannabis despite receiving specialized early intervention services. The finding that reducing use improved symptoms provides concrete motivation for cannabis-focused interventions in this population.

This study from real-world US clinical settings shows that even evidence-based early psychosis programs have limited impact on cannabis use. The clear symptom improvements in those who did reduce suggest that cannabis interventions should be a core component of early psychosis care.

Observational (cannot prove cannabis caused worse outcomes); selection effects (those able to reduce may differ in other ways); cannabis use self-reported; limited to US CSC programs.