Characteristics And Healthcare Resource Utilization Among Patients With Major Depressive Disorder Continuing, Switching, Or Discontinuing Therapy In A Real-World Setting

Many patients with major depressive disorder (MDD) switch or prematurely discontinue antidepressant therapy. This study aims to describe patient characteristics, healthcare resource utilization, and antidepressant persistence for patients continuing (≤45-day gap in refills following index fill), discontinuing, or switching therapies. This retrospective cohort study used US claims data from the HealthCore Integrated Research Database between 01/2014–02/2019 (index date=earliest antidepressant fill between 01/2015–02/2019). Patients were aged 18–64 years with ≥2 MDD diagnoses (including a diagnosis between 12 months prior and 1 month after index date) and continuous enrollment for 12 months before and after the index date. Pre-index and 1-year post-index patient characteristics and healthcare resource utilization are presented using descriptive statistics. Of 134,237 patients meeting study criteria, 39,121 (29.1%) were continuing, 34,457 (25.7%) switching, and 60,659 (45.2%) discontinuing therapies. Selective serotonin reuptake inhibitors were the most commonly prescribed (62%–68%) index antidepressant, followed by bupropion and mirtazapine (12%–15%). Mean age was 39.2, 42.9, and 40.0 years for patients switching, continuing, and discontinuing, respectively. The pre-index prevalence of co-morbid anxiety (using predefined ICD-9-CM and ICD-10-CM codes) was higher with switching than continuing/discontinuing (37% vs 30%–31%) and increased after post-index (66% vs 48%–52%). Pre-index office visits were highest among patients switching, which increased further post-index. Patients continuing and discontinuing had stable or reduced MDD-related inpatient/emergency room utilization post-index, while switchers showed an increase (inpatient, 5.6%–7.7%; emergency room, 3.9%–6.0%). Mean pre-index overall healthcare costs (medical+pharmacy) were higher with switching ($14,842) vs continuing ($13,474) and discontinuing ($12,612), and further increased with switching post-index ($17,731) vs continuing ($14,181) and discontinuing ($12,534). Patients who switch antidepressant therapy are younger, with comorbid anxiety disorders. Switching therapies is associated with higher overall healthcare costs and utilization. Future analyses will assess reasons for switching and/or discontinuation.