The Cost Consequences of Treatment-Resistant Depression

Objective: To describe health care costs of patients with treatment-resistant depression as their illness progresses, in terms of pharmaceutical and medical expenditures, and to identify factors associated with increasing degrees of treatment resistance.

Data Sources: The MEDSTAT MarketScan Private Pay Fee for Service (FFS) Database, a medical and prescription claims database covering over 3.5 million enrollees, from 1995-2000.

Design and Study Subjects: 7737 patients with depression (ICD-9) who had 2 or more unsuccessful trials of antidepressant medication at an adequate dose for at least 4 weeks from 1995-2000 were defined as treatment-resistant in this study. Demographic and clinical characteristics were assessed for these patients with treatment-resistant depression. The number of changes in depression medication treatment regimens was used as a proxy for increasing degrees of treatment resistance and its severity.

Major Outcome Measure: Differences in health care expenditures associated with increasing degrees of treatment-resistant depression.

Results: Total depression-related and general medical health care expenditures increased significantly as treatment-resistant depression increased in severity. Multivariate analyses of patient demographic characteristics were not associated with ongoing treatment resistance. Disease severity, type of antidepressant at index, comorbid mental health disorders, and membership in a managed health care plan were associated with increasing degrees of treatment resistance.

Conclusions: Depression and general medical health care expenditures increase with the degree of treatment-resistant depression. Disease management interventions for treatment-resistant depression that result in sustained remission early in the course of illness are most likely to be cost effective.