The impact of substance use at psychosis onset on First Episode Psychosis course: results from a 1 year follow-up study in Bologna.

Objectives: Substance abuse is a well established risk factor for First-Episode Psychosis (FEP), but its influence on FEP course is less clear. Starting from our baseline observation that substance users were younger than non-users at the psychosis onset, we hypothesized that substance use at baseline could be an independent risk factor for a worse clinical course.

Methods: An incidence cohort of patients with FEP collected in an 8year period (2002-2009) at the Bologna West Community Mental Health Centers (CMHCs) was assessed at baseline and at 12month follow-up. Drop-out, hospitalizations and service utilization were used as clinical outcomes.

Results: Most of the patients were still in contact with CMHC at 12month follow up. Substance users had a significantly higher rate of hospitalizations during the follow-up after adjusting for age, gender and other potential confounders (OR 5.84, 95% CI 2.44-13.97, p≤0.001).

Conclusions: This study adds to previous evidence showing the independent effect of substance use on FEP course. The identification of a "potentially modifiable" environmental predictor of the course of the illness such as substance use at psychosis onset allows us to envisage the possibility of ameliorating the course of the illness by managing this factor.