Prospective Service Use and Health Care Costs of Medicaid Beneficiaries with Treatment-Resistant Depression

BACKGROUND: Although the clinical and health economic characteristics of commercially insured adults with treatment-resistant depression (TRD) have been well characterized, little is known about TRD in the Medicaid population. OBJECTIVE: To describe clinical and health economic characteristics of adult Medicaid beneficiaries with TRD. METHODS: Retrospective longitudinal cohort analyses were performed with Truven Health MarketScan Medicaid Database (2008-2014), focusing on adults with major depressive disorder (MDD) following an index antidepressant prescription. TRD was operationally defined as starting a third treatment regimen after 2 adequate regimens of antidepressants or augmentation therapy within 12 months of an index antidepressant prescription. Among patients with and without TRD, percentages with inpatient admissions, emergency department visits, and outpatient visits (all cause, mental health related, and depression related) were determined. Logistic regression models were used to examine associations between TRD status and use of inpatient, outpatient, and emergency services. Separate analyses were performed for the first and second year after the index antidepressant prescription. RESULTS: Approximately one quarter (25.9%) of pharmacologically treated adults with MDD met criteria for TRD. In relation to MDD patients without TRD, patients with TRD were proportionately more likely to be older, male, and white. Compared with MDD patients without TRD, patients with TRD were also significantly more likely to receive inpatient care for any cause (31.0% vs. 21.6%; P < 0.001), a mental health-related reason (12.7% vs. 7.6%; P < 0.001), or depression (10.1% vs. 6.1%; P < 0.001) during the first year following their index antidepressant prescription. Over the second follow-up year, patients with TRD continued to be more likely than patients without TRD to receive inpatient care for any reason (26.7% vs. 19.5%; P < 0.001), a mental health-related reason (5.6% vs. 2.7%; P < 0.001), and depression (3.7% vs. 1.7%; P < 0.001). The mean health care costs of patients with TRD were also significantly higher than the costs of patients without TRD during the first year ($18,982 [SD ± $35,276] vs. $11,642 [SD ± $29,203]) and second year ($17,997 [SD ± $34,146] vs. $10,325 [SD ± $28,224]) following the index antidepressant prescription. CONCLUSIONS: In the U.S. Medicaid program, adults with TRD have substantially and persistently higher health care costs than their counterparts who do not meet criteria for TRD. The service use and health care cost patterns of patients with TRD in the Medicaid program highlight challenges of developing interventions and care coordination strategies to meet their complex clinical needs.