Cost-Benefit & Cost-Effectiveness Analysis of the Rapid Onset of Selective Serotonin Reuptake Inhibitors by Augmentation

Objective: This article describes a method for evaluating the value of the increased cost of pharmacologic augmentation of an antidepressant. Method: Data to illustrate the method and interpretation of results were derived from a randomized, placebo controlled double blind trial. Eighty outpatients meeting ICD-10 criteria for depressive disorder and scoring > 18 on the Montgomery-Asberg Depression Rating Scale (MADRS) were recruited from a primary care population. All patients received SSRI antidepressant and either augmenting agent or placebo. The trial period was six weeks, during which the patients were monitored for changes in depressive symptoms using the MADRS. The economic analysis is based only on direct costs of treatment. The analytic approach includes decision analysis, cost-effectiveness and cost-benefit techniques, and a sensitivity analysis. Results: The economic analysis was performed on both the intention-to-treat population and the per-protocol population. Intention-to-treat and per-protocol results show that the direct cost of six weeks' treatment with the combination of augmenting agent and SSRI antidepressant, if the acceleration effect is taken into account, was more cost effective than the SSRI antidepressant and placebo. Conclusion: The direct costs of treatment are higher than those of previous pharmacoeconomic studies, but the rate of onset of antidepressant action must be taken into account. The application of the evaluative model appears valid and useful. The model is pragmatic and should be expanded for generalizability.