Annual costs among patients with major depressive disorder and the impact of key clinical events

BACKGROUND: The economic burden of major depressive disorder (MDD) is substantial and increasing; however, the impact of key clinical events (eg, hospitalization, suicide attempt/ ideation, and treatment changes) on health care resource use and costs are less established. OBJECTIVE: To evaluate the health care utilization and costs among patients with MDD, particularly for those with key clinical events. METHODS: In this retrospective analysis, administrative health care claims from the IBM MarketScan Commercial Claims and Encounters Database were used to identify adults with a new diagnosis of MDD (January 1, 2009, to December 31, 2017). Patients with 12 months or more of continuous health care coverage before and after the initial medical claim with an MDD diagnosis (index date) and 1 or more pharmacy claims for an antidepressant within 60 days of any qualifying medical claim were included. The effect of post-index date key clinical events (eg, treatment changes, moderate to severe MDD, MDD-related emergency department [ED] visits, MDD-related hospitalizations, suicide attempt/ideation, severe mental health disorder, use of brain stimulation therapies) on all-cause total costs was assessed. Actual allcause costs were summarized descriptively and reported per patient per year (PPPY). Multivariable analyses compared differences in all-cause costs during follow-up, depending on whether patients experienced a key clinical event. RESULTS: A total of 455,082 patients met eligibility criteria. The average age was 41 years and 64% of patients were female. Mean (SD) all-cause PPPY costs during the followup period were $10,074 ($ 25,694). The most common key clinical events were treatment changes, moderate to severe MDD diagnosis, and MDD-related ED visits. The majority of patients (90.1%) experienced at least 1 treatment change, which was most commonly treatment discontinuation. Generally, mean costs for up to 90 days following an event were higher than those preceding the event. In multivariable analyses, patients with any key clinical events had 51% higher PPPY allcause health care costs compared with those who did not have any key clinical events. Compared with patients without key clinical events, follow-up costs were more than 2 times higher among patients with severe mental health disorder, MDD-related hospitalization, and suicide attempt/ideation. The most impactful key clinical event was treatment with electroconvulsive therapy, vagal nerve stimulation, or transcranial magnetic stimulation, in which patients incurred 4.3 times higher follow-up costs than those who did not receive one of these treatments. CONCLUSIONS: Key clinical events exacerbate health care resource use and costs among patients with MDD. Effective therapeutic regimens initiated optimally in the course of treatment may mitigate costly clinical events associated with MDD.