Clinical and economic burden of obstructive hypertrophic cardiomyopathy in the United States.

Aims: Obstructive hypertrophic cardiomyopathy (oHCM) is a disease of the cardiomyocyte in which dynamic left ventricular outflow track obstruction may lead to heart failure, valvular disease, and sudden death. Little is known about healthcare resource utilization (HRU) and costs associated with oHCM. This study investigated the clinical and economic burden of oHCM in patients with or without symptoms associated with oHCM.

Methods: We used the US IBM MarketScan Commercial and Medicare Supplemental database to identify patients with oHCM (January 2009-March 2019). Control patients without cardiomyopathy were matched to each patient with oHCM based on age, sex, region, and index year (3:1 ratio). One-year HRU and cost data were compared between all oHCM, symptomatic oHCM, and asymptomatic oHCM subgroups, and their respective controls.

Results: Among 11,401 eligible patients with oHCM (mean age 57 years, 42% female), 5,667 (50%) were symptomatic (23% chest pain, 57% dyspnea, 29% fatigue, 17% syncope). oHCM was associated with significant increases in all-cause hospitalizations, hospital days, outpatient visits, and total healthcare costs (mean ± standard deviation: $26,929 ± 77,720 vs. $6,808 ± 25,712, <.001) compared with matched controls. These differences were driven mainly by the clinical and economic burden of symptomatic oHCM, which was associated with significant increases in 1-year hospitalization rates (38.0 vs. 6.9%), hospital days (3.7 ± 9.9 vs. 0.4 ± 3.0), and total healthcare costs ($43,586 ± 103,756 vs. $6,768 ± 27,618; all <.001). Adjustment for comorbidities had minimal impact on these differences.

Limitations: The use of claims data relies on International Classification of Diseases (ICD-9 and ICD-10) diagnosis codes, which might be inaccurate. Only commercially insured patients were included.

Conclusion: In a real-world population, oHCM was associated with substantial increases in HRU and incremental costs of ∼$20,000/year when compared with matched controls-a difference that increased to ∼$35,000/year among symptomatic patients. Further studies are warranted to understand the potential impact of specific therapies on HRU and the economic burden of oHCM.