SUBSTANCE-ABUSE AND ONSET OF PSYCHOTIC ILLNESS

Objective: This study examined the relationship of substance abuse his tory to psychotic diagnosis and clinical presentation in a sample of 1 88 subjects with newly diagnosed psychotic illness. Methods: Subjects were assessed using a structured diagnostic interview and clinical rat ing scales. The diagnosis and demographic and clinical characteristics of subjects with a substance abuse history were compared with those o f subjects without a substance abuse history. Data for males and femal es were considered separately in most analyses. Results: Substance abu se history was unrelated to initial diagnosis, age at onset of psychot ic symptoms, ratings of best and worst levels of functioning, or sever ity of positive symptoms. Substance abuse was significantly associated with higher anxiety and depression scores on the Brief Psychiatric Ra ting Scale. Males without substance abuse had more negative symptoms a nd were less likely to have attempted suicide than males with substanc e abuse. Conclusions: Substance abuse appears to have limited influenc e on the clinical presentation of non-substance-induced psychotic diso rders.