Objective: To investigate the patterns and predictors of substance use disorders (SUD) and daily tobacco use in first-episode psychosis (FEP).
Method: In this study, consecutive admissions of 126 patients with an initial presentation for FEP were recruited from three psychiatric services. Each patient was assessed with a comprehensive assessment package in order to collect demographic information, to diagnose psychotic disorders and SUD, to estimate the duration of untreated psychosis and to assess premorbid functioning and the severity of psychiatric symptoms.
Results: The rates of lifetime SUD and daily tobacco use were 71% and 77%, respectively. The onset of SUD pre-dated the onset of positive psychotic symptoms in 91% of relevant cases. In multivariate analyses, male gender, younger age, Australian birth and unemployed status were the most consistent demographic predictors of SUD and daily tobacco use. There were no associations found between SUD and symptom severity, premorbid adjustment, psychotic disorder diagnosis or hospitalization.
Conclusions: Male gender and younger age are reliable predictors of SUD in FEP. Patients with and without SUD appear to have similar clinical characteristics at initial presentation.