Drug utilization patterns and outcomes associated with in-hospital treatment with risperidone or olanzapine

This study compared the drug-utilization costs and indicators of clinical outcomes associated with the use of risperidone and olanzapine in a hospital setting. We conducted a nonrandomized, retrospective chart review of consecutive patients identified as presenting with psychotic symptoms on inpatient wards at Riverview Hospital in British Columbia and given either risperidone or olanzapine as their first new drug after reassessment (n = 30 per treatment group). Data were collected for up to 120 days. No significant differences were observed between groups in terms of sex, age, duration of illness, or diagnosis. The mean dosage of risperidone for responders was 4.89 +/- 2.56 mg/d, whereas that for olanzapine was 17.19 +/- 3.88 mg/d. The associated daily drug-acquisition costs were significantly different, at CA$4.69 for risperidone and CA$11.52 for olanzapine. Notes in patient charts indicated that a significantly greater proportion of risperidone-treated patients (60.0%) than olanzapine-treated patients (26.7%) responded to therapy, as indicated by improvement in at least one target symptom (P < 0.01). Forty percent of patients initially treated with risperidone were discharged on their original therapy, compared with 13.3% of patients treated with olanzapine (P < 0.05). These results were not substantially affected by correction for markers of illness severity or treatment resistance. Overall, no significant differences in side effects were recorded in the patient records of the two groups. Within this cohort of patients, risperidone treatment was associated with lower drug-acquisition cost and better treatment outcomes than olanzapine.