PMH13: PRE-TREATMENT PATIENT DIFFERENCES: CHOICE OF DRUG THERAPY WITHIN SCHIZOPHRENIA

Abstract

OBJECTIVE: To examine pre-treatment differences in characteristics of patients with schizophrenia treated with olanzapine and risperidone, as reported in epidemiologic studies. METHOD: All 15 non-randomized studies with olanzapine and risperidone cited in Medline or presented at major conferences (APA, ECNP, WPA, ISPOR) through 1999 were included. The direction, magnitude, and statistical significance from all comparisons of pre-treatment characteristics for schizophrenia patients initiating therapy on olanzapine or risperidone are summarized. RESULTS: Several studies found olanzapine patients were more likely to be younger and male. One of six studies found younger mean age at onset, though prior duration of illness results had no consistent direction. Other specific comparisons were included in only one or two studies. History of hospital admission results were mixed, though olanzapine patients had significantly higher prior hospitalization costs in the one study with that measure. Patients initiated on olanzapine were more likely to have prior use of clozapine, depot antipsychotics, and/or antidepressants, whereas patients initiated on risperidone were more likely to have anticholinergic use at therapy start. In one study, patients initiated on olanzapine had mean CGI scores and/or GAF scores indicative of greater severity. CONCLUSIONS: When evaluated, significant pre-treatment patient differences were often found. Physicians may be choosing olanzapine therapy for more complicated schizophrenic patients, indicated by prior hospitalization cost, medication use, and clinical assessment scores.