(35) Descriptive Analysis of ATTR-CM Patients Enrolled in Medicare Advantage.

Background: : Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive, infiltrative form of heart failure (HF) that results from misfolded transthyretin protein deposits in the myocardium. Tafamidis was the first treatment FDA approved in 2019, and therapies continue to evolve including the recent approval of acoramidis in 2024 and vutrisiran in 2025. There is a lack of real-world evidence from a US payer perspective on trends in the recognition and treatment of ATTR-CM and associated healthcare resource use and clinical outcomes among Medicare Advantage (MA) enrollees.

Objective: : The objective of this study was to describe ATTR-CM diagnosis trends, and examine ATTR-CM patient characteristics, clinical outcomes, and healthcare resource use (HRU) among MA enrollees.

Methods: : This study was conducted using the Humana Research Database. Annual trend in number of MA members diagnosed with ATTR-CM (per 100,000 enrollees) was assessed from 2019 to 2023. A longitudinal cohort of MA members aged 18-89 years and newly diagnosed with ATTR-CM (index event) from 01/01/2020 and 02/28/2024 was identified. Twelve-month pre-index and at least 6 months post-index enrollment was required. Comparisons of baseline characteristics and HRU were conducted for treated versus untreated patients.

Results: : The number of ATTR-CM patients increased each year, from 3.4/100k in 2019 to 13.7/100k MA enrollees in 2023. We identified 529 newly diagnosed ATTR-CM patients with median of 19 months follow-up. Among these patients 52.6% initiated tafamidis treatment during follow-up, and 29.1% of those discontinued tafamidis at a later point. Baseline characteristics were similar for treated and untreated. During follow-up greater proportion of treated patients had cardiologist visits (80.9% vs 72.9%; P=0.028) and fewer treated patients had emergency department (ED) visits (54.0% vs 65.3%; P=0.008). Overall, 21.9% had all-cause death during variable follow-up. Significant predictors of mortality were age (75-84 years, HR: 1.73, 95%CI: 1.02-2.95, P=0.044; >85 years, HR: 3.72, 95%CI: 1.93-7.18, P< 0.001; reference group, 65-74), evidence of fatigue (HR:1.62, 95%CI: 1.06-2.47, P=0.026) and ED visits (HR: 1.64, 95% CI: 1.07-2.52, P=0.023) prior to diagnosis, and ESRD as the original reason for Medicare enrolment (HR: 3.86, 95% CI: 1.38-10.80, P< 0.010).

Conclusions: : The number of MA enrollees with ATTR-CM diagnosis increased from 2019 to 2023. Approximately half of newly diagnosed patients received tafamidis treatment. Factors associated with greater risk of mortality were identified.

Sponsorship:: None.