Impact of persistent substance misuse on 1-year outcome in first-episode psychosis

Background Substance misuse is a common comorbid problem in people presenting with first-episode psychosis and is associated with a poor short-term outcome. Aims The aim of this study is to examine differences in baseline characteristics and 1-year outcome between individuals with first-episode psychosis who have never misused substances, those who stop misusing substances after initial presentation and those who persistently misuse substances over the 1-year assessment period. Method Patients were recruited to the Northern Ireland First Episode Psychosis Study (n=272). Clinical assessments were performed at baseline and at 1 year (n=194) and data were collected from the case notes. Results Individuals with persistent substance misuse had more severe depression, more positive symptoms, poorer functional outcome and greater rates of relapse at 1 year than those who stopped and those who had never misused substances. There were no differences in outcome between people who had never misused substances and those who stopped misusing after presentation. Conclusions These results support assertive intervention targeted at comorbid substance misuse in individuals with first-episode psychosis.