Describe all-cause healthcare resource utilization (HCRU), costs, and time-to-event outcomes among newly diagnosed epilepsy patients with and without comorbid depression.

Depression is linked to increased HCRU and costs in epilepsy, but few studies have examined changes across subsequent lines of therapy (LOTs) or their relation to time-to-event outcomes.

This retrospective study utilized 100% Medicare Fee-for-Service claims and Inovalon’s MORE² database (01/01/2016–12/31/2023) to identify incident epilepsy patients (01/01/2017–12/31/2019), defined by ≥2 outpatient or ≥1 inpatient claims. Patients were stratified by the presence or absence of depression during pre-index period. The index date was initiation of the first LOT lasting ≥30 days. Continuous enrollment of ≥12 months pre-index and ≥24 months post-index was required. LOTs ended with treatment discontinuation (≥60-day gap), switch, augmentation, or partial drop. Four LOTs were captured. All-cause HCRU and costs were reported per patient per month (PPPM) for each LOT. Total costs included all medical and pharmacy spending, adjusted to 2023 U.S. dollars.

Among 90,738 patients, 21,388 (24%) had comorbid depression. Patients with depression had significantly higher HCRU vs. those without depression, including more office visits (1.14 vs. 0.97 visits PPPM), emergency department (ED) visits (0.49 vs. 0.27 visits PPPM), and longer mean length of stay (11.2 vs. 8.4 days; all p<.0001). Total healthcare costs were significantly higher at index ($6,209 vs. $4,239 PPPM, p<.0001) and remained elevated across subsequent LOTs. Median time to first hospitalization was 3.5 vs. 5.6 months; median time to first ED visit was 2.4 versus 3.9 months, respectively.

Patients with comorbid depression demonstrated significantly higher HCRU and costs compared to those without depression, persisting across subsequent LOTs. Earlier median times to hospitalization and ED visits were observed in the depression cohort. Findings underscore the clinical and economic burden of depression and the need for comprehensive management strategies addressing psychiatric comorbidities.