[Cost effectiveness analysis of olanzapine versus haloperidol in the treatment of schizophrenia++ in Spain].

Background: Cost-effectiveness of olanzapine in comparison with haloperidol, in Spanish schizophrenic patients, was analysed using a clinical decision model.

Methods: The model represents a simulation of the different clinical and therapeutic possibilities that an hypothetical cohort of patients could experienced in a 5-years period of treatment. Efficacy was measured as months with partial-complete remission. Most information was obtained from the HGAJ randomised clinical trial. Other information was estimated through literature reviews and the opinion of an expert panel.

Results: Average cost-effectiveness for olanzapine was lower (116,476 pesetas per month with partial-complete remission) than for haloperidol (134,762 pesetas per month with partial-complete remission). Olanzapine produced more than half year (6.7 months) with partial complete remission, in comparison with haloperidol, with antincrementar cost-effectiveness of 32,516 pesetas per month with partial-complete remission, in comparison with haloperidol. The results were not sensitive to changes in the values of the main variables used in the analysis.

Conclusions: According to this analysis, olanzapine presents a good cost-effectiveness relationship in comparison with baloperidol, in Spanish schizophrenic patients. The analysis will be completed when new studies comparing olanzapine with other antipsychotics are available.