OBJECTIVE: The goals of this study were 1) to determine the extent of
substance abuse in patients with treatment-resistant schizophrenia and 2)
to assess the relevance of such abuse to subsequent response to treatment
with clozapine. METHOD: The subjects were 118 treatment- resistant patients
with DSM-III-R diagnoses of schizophrenia or schizoaffective disorder who
underwent detailed demographic, clinical, and psychopathological
evaluations before commencing treatment with clozapine. Lifetime and
current histories of substance abuse were also systematically evaluated and
characterized according to the Research Diagnostic Criteria and DSM-III-R.
Response to clozapine treatment at 6 months was determined with measures of
psychopathology and psychosocial function. RESULTS: An antecedent or
current history of substance abuse was determined for 29 patients. Although
predominantly male, the abusers did not differ from the nonabusers on other
demographic features. The substance abusers actually showed less
psychopathology (negative and disorganization symptoms) and better
psychosocial functioning at baseline; however, both groups attained similar
improvements on these measures after 6 months of clozapine therapy.
CONCLUSIONS: A modest extent of previous or current substance abuse was
observed among neuroleptic-resistant schizophrenic patients who
subsequently received treatment with clozapine. This antecedent history of
substance abuse did not appear to negatively influence subsequent response
to clozapine treatment.