Sociodemographic and clinical characteristics of patients presenting with first-episode psychosis and concurrent substance misuse

Aims: To determine the incidence of concurrent substance misuse among individuals entering first-episode psychosis treatment, and examine whether patients with concurrent substance misuse differ on variables relevant to service planning. Methods: Consecutive patients (n = 376) were assessed using standardized instruments. Results: Twenty-two per cent met abuse or dependence criteria for a single substance, and 8% met criteria for two substances. Most met criteria for marijuana or marijuana and alcohol. The majority of patients with a concurrent disorder were male, and on average they were 3.5 years younger at psychosis onset. Patients with a concurrent disorder experienced worse 'positive' and anxiety symptoms in the month before treatment. Premorbidly they had better social functioning, but worse academic functioning. Conclusions: There are important differences between patients entering first-episode psychosis treatment with and without a concurrent substance misuse. Early intervention efforts might be informed by our accumulating knowledge about the characteristics of patients who have both disorders.