OBJECTIVES: Atrial fibrillation (AF) is common among patients with symptomatic obstructive hypertrophic cardiomyopathy (soHCM), but the burden of AF on HCM-related healthcare resource use (HCRU) and cost is unknown. Therefore, we sought to assess the economic impact of AF on patients with soHCM.

METHODS: Symphony medical and pharmacy claims data were assessed for the years 2016–2021 to identify (ICD-10 code) adult patients with treatment-naïve soHCM in the United States. We defined symptomatic as evidence of either fatigue, chest pain, syncope, dyspnea, heart failure, or palpitations within 3 months of index date and comorbid AF as AF within 3 months of index date. Unadjusted HCM-related HCRU and charges (per-person per-year [PPPY], in USD) were reported for the following categories: hospitalizations (number and length of stay); outpatient, emergency-room, or urgent-care visits; or pharmacy use.

RESULTS: Of 9490 patients with soHCM, 2681 (28.3%) had AF. Patients with AF were older (median 68 vs 63 years; p<0.0001) and more were male (48.0% vs 42.5%; p<0.0001). Among all patients, the majority were on Medicare (39%) and Commercial (19%) insurance. Patients with vs without AF averaged significantly more HCRU across all categories assessed (all p<0.05). Total HCM-related charges were greater for patients with AF vs without (mean $26,607 vs $17,202 PPPY; p<0.0001). Across all categories, HCM-related charges were greater in patients with comorbid AF, with the majority of HCM-related total charges resulting from outpatient visits ($19,863 vs $13,416; p<0.0001) and hospitalizations ($4117 vs $2027; p<0.0001).

CONCLUSIONS: In this US-based cohort of patients with soHCM, those with comorbid AF incurred significantly more HCM-related HCRU and higher costs PPPY. This suggests that comorbid AF in soHCM is associated with a greater economic burden. In patients with soHCM, better management, including novel treatments, could reduce the additional economic burden in those with comorbid AF.