Background: Among patients with major depressive disorder (MDD), those with treatment-resistant depression (TRD) have a higher economic burden. However, healthcare resource utilization (HRU) and costs may vary by MDD severity in patients with TRD.
Objectives: To compare treatment patterns, HRU and costs of TRD by MDD severity.
Methods: A claims-based algorithm identified patients with TRD in a US database of privately insured employees and dependents (OptumHealth Care Solutions, Inc; 01/2010-03/2015). Patients with TRD were stratified into mild, moderate and severe cohorts based on the information in the last observed MDD ICD-9-CM code. HRU and costs of moderate and severe cohorts were compared to those of the mild control cohort using regression models adjusted for patient baseline characteristics. Treatment patterns were compared.
Results: Among 6,411 patients with TRD, 455 (7.1%) were identified as mild, 2,153 (33.6%) as moderate and 1,455 (22.7%) as severe. Pharmacotherapy use was similar across cohorts. In terms of all-cause HRU, moderate and severe patients compared to mild had 45% and 150% more inpatient admissions, 65% and 164% more inpatient days, 18% and 54% more emergency department visits and 8% and 10% more outpatient visits per-patient-per-year, respectively (all p<0.05). The magnitude of differences in mental-health and depression-related HRU among moderate and severe versus mild patients was even greater. The incremental all-cause HRU resulted in all-cause total healthcare cost differences of $3,455 in moderate and $5,150 in severe versus mild patients, respectively (per-patient-per-year; all p<0.05).
Conclusions: Increased MDD severity is associated with incremental economic burden in patients with TRD.