Tricyclic antidepressant and selective serotonin reuptake inhibitors antidepressant selection and health care costs in the naturalistic setting: a multivariate analysis.

BACKGROUND: Providers and payers have an interest in the total health care costs following the initiation of antidepressant treatment in the real world of clinical practice. Analyses of these costs can help evaluate the economic consequences of patient management decisions associated with initial antidepressant selection.

OBJECTIVE: The purpose of this study was to assess the 1-year total direct health care costs for patients initiating therapy with one of the available tricyclic antidepressants (TCAs) or one of the three most often prescribed selective serotonin reuptake inhibitors (SSRIs) - paroxetine, sertraline, or fluoxetine.

METHOD: A two-stage multivariate econometric model and data from fee-for-service private insurance claims between 1990 and 1994 were used to estimate the total direct health care costs following initial antidepressant drug selection for 2693 patients with a 'new' episode of antidepressant treatment. After controlling for both observed and unobserved characteristics, the 1-year total direct health care costs were found to be (1) statistically significantly lower for patients initiating therapy on fluoxetine than for patients initiating therapy on a TCA; (2) statistically significantly lower for patients who initiated therapy on fluoxetine than for patients initiating therapy on sertraline.

CONCLUSIONS: Broadly considered, the findings in this study suggest that total direct health care costs differ across initial antidepressant selection after controlling for both observed and unobserved characteristics.