An Evaluation of the Clinical and Economic Burden Among Older Adult Medicare-Covered Beneficiaries With Treatment-Resistant Depression

Abstract

Objective: To compare the clinical and economic burden of treatment-resistant depression (TRD) among older adult patients with major depressive disorder (MDD) to non-TRD MDD and non-MDD patients.

Methods: Retrospective cohort study using 5% Medicare data (January 1, 2012-December 31, 2015) for MDD patients aged ≥65 years who were defined as TRD if they received ≥2 antidepressant treatments in the current episode. MDD patients not meeting TRD criteria were deemed non-TRD MDD; those without an MDD diagnosis were categorized as non-MDD. All were required to have continuous health plan enrollment for ≥6 months pre- and ≥12 months postindex date (index: first antidepressant claim/random [non-MDD]). Three cohorts were matched, and generalized linear and Cox proportional hazards models were used to compare medication use, healthcare resource utilization, costs, and risks of initial hospitalization and readmission ≤30 days postdischarge from initial hospitalization.

Results: After matching, 178 patients from each cohort were analyzed. During 12 months of follow-up, TRD patients had higher use of different antidepressants and antipsychotics, higher inpatient and emergency room visits, longer inpatient stays, and higher total healthcare costs ($24,543 versus $16,059, $8,058) than non-TRD MDD and non-MDD cohorts, respectively (all p <0.05). Risk of initial hospitalization was higher in the TRD (hazard ratio [HR] = 3.60, 95% confidence interval [CI] = 2.08-6.23) and non-TRD MDD cohorts (HR = 1.82, 95% CI = 1.02-3.25) than the non-MDD cohort.

Conclusions: The burden of MDD among older adult Medicare beneficiaries is substantial, and even greater among those with TRD compared to non-TRD MDD, demonstrating the need for more effective treatments than those currently available.

Keywords: Antidepressants; major depressive disorder; older patients; treatment-resistant depression.