A POPULATION-BASED COST-EFFECTIVENESS ANALYSIS OF OLANZAPINE AND RISPERIDONE AMONG AMBULATORY PATIENTS WITH SCHIZOPHRENIA

Dan Cooper; Jocelyne Moisan; Belkacem Abdous; Jean-Pierre Grégoire

Dan Cooper

Research Centre, CHU Sainte-Justine, Montreal, Quebec, Canada

Jocelyne Moisan

Faculty of Pharmacy, Université Laval, Québec, Canada; hospitalier affilié universitaire de Québec, Québec, Canada

Belkacem Abdous

hospitalier affilié universitaire de Québec, Québec, Canada, 3 Department of Social and Preventive Medicine, Université Laval, Québec, Canada

Jean-Pierre Grégoire

Faculty of Pharmacy, Université Laval, Québec, Canada; Department of Social and Preventive Medicine, Université Laval, Québec, Canada

Keywords

Drugs, antipsychotic, schizophrenia, cost effectiveness, database

Abstract

Background

Olanzapine and risperidone are atypical antipsychotics exhibiting different pharmacological properties

that are likely to translate into differences in outcomes, tolerability and safety. As well, their acquisition cost differs. These differences may impact their cost-effectiveness.

Objective

To estimate the incremental cost-effectiveness ratio (ICER) of olanzapine and risperidone in an outpatient population.

Methods

We carried out a cost-effectiveness analysis based on resource utilization data gathered from Quebec’s provincial health insurance board databases. Patients previously diagnosed with schizophrenia who

received a first prescription of olanzapine or risperidone between 1 January 1997 and 31 August 1999 were followed for 365 days. Absence of hospitalization for mental illness served as the clinical indicator of effectiveness. Direct health care costs for mental illness were considered. Adjusted ICERs were calculated, and their 95% confidence intervals (CI) were assessed using a non-parametric bootstrap.

Results

A total of 6,334 patients were included in the analysis. The ICER for olanzapine was (CA$) 86,918

(95%CI, 27,709 to 237,040) per additional effective treatment per year, among patien ts hospitalized prior to their treatment. Among those who were not hospitalized prior to their treatment, olanzapine was dominated (95%CI, CA$1.7M to dominated).

Conclusion

Results suggest that, in this population, direct mental health care costs could be minimized by using

risperidone instead of olanzapine as the initial treatment.

Abstract 166 | PDF Downloads 169

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Published

Dec 8, 2018

How to Cite

Cooper, D., Moisan, J., Abdous, B., & Grégoire, J.-P. (2018). A POPULATION-BASED COST-EFFECTIVENESS ANALYSIS OF OLANZAPINE AND RISPERIDONE AMONG AMBULATORY PATIENTS WITH SCHIZOPHRENIA. Journal of Population Therapeutics and Clinical Pharmacology, 15(3). Retrieved from https://jptcp.com/index.php/jptcp/article/view/229