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Dan Cooper
Jocelyne Moisan
Belkacem Abdous
Jean-Pierre Grégoire


Drugs, antipsychotic, schizophrenia, cost effectiveness, database



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.



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



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.



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).



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

risperidone instead of olanzapine as the initial treatment.

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