Reductions in cannabis and other illicit substance use between treatment entry and early recovery in patients with first‐episode psychosis

Abstract

Abstract Objective: Reductions in cannabis use have been observed during the first year following treatment entry for first‐episode psychosis (FEP), but there is little indication of the pattern of cannabis and substance misuse generally in the very early course of treatment. Methods: Patterns of cannabis and other substance use (including alcohol) were examined prospectively among 130 FEP patients assessed at treatment entry and again at early follow up (median 9 weeks 4 days). Differences between cannabis users and non‐users at both time‐points were compared on descriptive features, psychopathology, social functioning and functional disability. Results: Of 72 patients using cannabis at treatment entry, 29 (40.3%)were abstinent at follow up. Notably, almost half (41%) of those cannabis users who were abstaining at follow up had been using on a daily or multiple daily basis. Among 58 individuals abstinent at treatment entry, 11 (19%) had commenced cannabis use at follow up. There were no significant differences between cannabis users and non‐users on any psychopathology measure at treatment entry, however, those using cannabis at early follow up scored significantly higher than non‐users on general psychopathology and positive symptomatology, and lower on health functioning. Conclusions: This study demonstrates significant fluctuation in cannabis use in the context of receiving specialist treatment for FEP, and suggests that a substantial proportion of young patients are contemplating changing harmful patterns of use in this critical early phase.