Associations of Sex on Economic Burden in Patients with Symptomatic Obstructive Hypertrophic Cardiomyopathy: Results from Medical and Pharmacy Claims Data

Michael Butzner ^1* Sanika Amonkar ² Meiling Chen ² Eros Papademetriou ³ Ravi Potluri ³ David Rotter ³ Theodore Abraham ²

• ¹ Cytokinetics (United States), South San Francisco, United States
• ² School of Medicine, University of California San Francisco, San Francisco, California, United States
• ³ Putnam Associates, New York, New York, United States

Background: Previous studies of patients with symptomatic obstructive hypertrophic cardiomyopathy (oHCM) have reported worse clinical burden for female patients; whether this translates to an increase in healthcare resource use (HRU) and cost is unknown. Therefore, we evaluated the impact of sex on economic burden in symptomatic oHCM.Methods: Medical and pharmacy claims data were assessed from 2016-2021 to identify (ICD-10 code) adult patients with symptomatic oHCM in the United States. Generalized linear models were used to estimate HCM-related cost and generalized estimating equations for HRU (both reported as mean per-person-per-year (PPPY)) for healthcare categories: inpatient, outpatient, emergency room (ER), urgent care, and pharmacy. Cox proportional hazard regressions were used to compare differences in male and female patients with symptomatic HCM.Results: Among 9,490 patients with symptomatic oHCM, 5,309 (55.9%) were female. Female patients were older (64±13 vs 59±14), with a higher Charlson Comorbidity Index (1.9 vs 1.7) compared to males, respectively. After adjusting for patient characteristics, female patients had significantly greater number of HCM-related hospitalizations (0.24 vs 0.20 PPPY, p=0.0014), LOS (5.08 vs 4.30 PPPY; p=0.0235), number of outpatient visits (4.98 vs 4.59 PPPY; p=0.0387), and number of distinct drugs (0.59 vs 0.55 PPPY; p=0.0010), compared with males, respectively. In adjusted models, only HCM-related pharmacy costs were significant, with female patients having slightly higher costs compared to males ($70 vs $61 PPPY; p= 0.0465). There were no significant differences in all-cause costs of care between male and female patients with oHCM.Conclusions: Female patients with symptomatic oHCM experience greater rates of HCM-related and all-cause hospitalizations and number of prescriptions, and HCM-related length of stay, outpatient visits, and pharmacy costs compared to male patients.