Substance use disorder among people with first-episode psychosis: a systematic review of course and treatment.

OBJECTIVE: People experiencing a first episode of psychosis frequently have co-occurring substance use disorders, usually involving alcohol and cannabis, which put them at risk for prolonged psychosis, psychotic relapse, and other adverse outcomes. Yet few studies of first-episode psychosis have addressed the course of substance use disorders and the response to specialized substance abuse treatments.

METHODS: The authors searched MEDLINE, PsycINFO, and other medical databases for English-language articles published between 1990 and 2009. Included studies addressed two research questions. First, do some clients become abstinent after a first episode of psychosis without specialized substance abuse treatments? Second, for clients who continue to use substances after a first episode of psychosis, does the addition of specialized substance abuse treatment enhance outcomes?

RESULTS: Nine studies without specialized substance abuse treatment and five with specialized substance abuse treatment assessed the course of substance use (primarily cannabis and alcohol) after a first episode of psychosis. Many clients (approximately half) became abstinent or significantly reduced their alcohol and drug use after a first episode of psychosis. The few available studies of specialized substance abuse treatments did not find better rates of abstinence or reduction.

CONCLUSIONS: Experience, education, treatment, or other factors led many clients to curtail their substance use disorders after a first episode of psychosis. Specialized interventions for others need to be developed and tested.