Real-world treatment and health care utilization among patients with Duchenne muscular dystrophy by race and ethnicity in a Medicaid population

Abstract

Background: Duchenne muscular dystrophy (DMD) is a rare neuromuscular disorder, and data on the impact of patients' race on treatment outcomes and health care resource utilization are lacking.

Objective: To describe the real-world treatment and health care utilization among patients with DMD, by race, in a Medicaid population.

Methods: This was a retrospective cohort study of patients with DMD in the Merative Multi-State Medicaid Database between January 2017 and June 2021. Patients with DMD were identified using a validated algorithm and included male patients with at least 2 DMD diagnoses (earliest DMD diagnosis date = index date), aged 40 years or younger, with at least 12 months of continuous enrollment prior to index date, and with at least 12 months (or evidence of death) following the index date were selected. Demographics, clinical characteristics, treatment utilization, and health care utilization and costs were reported by race and ethnicity in the 12-month baseline and 12-month follow-up periods.

Results: A total of 561 patients were included in the study, of which 360 (64.2%) were White, 50 (8.9%) were Black, 33 (5.9%) were Hispanic, and 118 (21.0%) were of other/unknown race and ethnicity. The median age on the index date was 16, 13, 14, and 15 years among the race and ethnicity categories, respectively. In the follow-up, period clinical characteristics were similar across cohorts. Corticosteroids were the most commonly received treatment, with the highest use among Hispanic patients (73%) and lowest use among Black patients (52%). A third of patients treated with corticosteroids received deflazacort, with similar utilization across groups. Exon-skipping therapy use was rare, with 3% utilization overall, and highest use among White patients (4.2%). In both the baseline and follow-up periods, differences in health care costs were not statistically significant. White patients had the highest total costs in the follow-up period (mean [SD] = $108,895 [$346,934]) compared with $59,501 [$85,758] in the Black cohort, $61,199 [$67,021] in the Hispanic cohort, and $65,247 [$119,733] in the unknown/other cohort. Differences in total health care costs were driven by outpatient pharmacy costs, likely because of the larger proportion of White patients having a prescription for an exon-skipping therapy.

Conclusions: Differences were seen across race and ethnicities in select clinical characteristics, DMD treatments, and health care utilization and costs in a Medicaid population.

FIGURE 1

Mean All-Cause Health Care Costs in the Baseline and Follow-Up Periods