MA Fuller, Cleveland VAMC; KM Shermock, The Cleveland Clinic Foundation; M Secic, The Cleveland Clinic Foundation; JS Laich, Cleveland VAMC; MB Durkin, Janssen Pharmaceutica

Objectives: To determine the change in health care utilization and costs from one year prior to starting risperidone or olanzapine treatment (pre-period) to one year after starting treatment (post-period) in schizophrenic patients in a Veterans Administration (VA) population.

Methods: Schizophrenic patients, identified by a claim for services with a diagnosis of schizophrenia (ICD-9 CM code 295) in the pre-period, who had an initial prescription for risperidone or olanzapine dispensed between 3/97 and 3/99 were assigned to the risperidone (R) or olanzapine (O) group, respectively. Patients who received any atypical antipsychotic in the pre-period were excluded from analysis. Comparisons of average change in utilization and cost from the pre period to the post period were made between the groups for four dependent (outcome) variables: inpatient hospitalizations, outpatient clinic visits, medications, and total healthcare cost (sum of the costs for the previous three variables). Inpatient health care utilization data was collected from the Patient Treatment File (PTF). Outpatient and medication utilization data was collected from the Veterans Integrated Health Systems Technology and Architecture (VISTA). To calculate costs, units of utilization were multiplied by year and ward/clinic-specific costs from the Cost Distribution Report (CDR). Medication costs were obtained from the VA Drug File. Analysis of covariance (ANCOVA) was used to analyze the data using age, gender, and race as covariates.

Results: A total of 304 patients in the olanzapine (O) group and 344 patients in the risperidone (R) group met the inclusion criteria. The O group had significantly more inpatient admissions per patient (O:0.09 vs. R:-0.24, p=0.026), longer inpatient lengths of stay (O: 4.3 days vs. R:-4.2 days, p=0.004), and higher cost of inpatient admissions (O: $2735 vs. R: -$3226, p=0.003) as compared to the R group. There was a significantly lower cost of antipsychotic for the R group as compared to the O group (R: $650 vs. O: $1660, p<0.001). The mean daily dose for the R group was 3.4 mg and 12 mg for the O group. The olanzaapine group also had significantly higher change in cost for all drugs (R: $683 vs. O $1492, p<0.001) and change in all costs (inpatient, outpatient, and medication) compared with the R group

(R:-$1,167 vs. O: $5665, p<0.001)

Conclusions: These data indicate that in atypical-naive schizophrenic patients started on either risperidone or olanzapine, the change in total health care cost for risperidone treated patients is significantly lower compared with olanzapine treated patients. Better inpatient outcomes (number and length of stay of inpatient admissions) and lower cost of medications were the main contributors to the lower total health care costs on risperidone.

Impact: Atypical antipsychotics are high cost budget items for pharmacy departments. Preferential use of one antipsychotic affects not only pharmacy drug budgets but also total health care costs. These data support that using risperidone over olanzapine may significantly decrease total health care costs in atypical antipsychotic naive schizophrenic patients.