Objective:

To understand how patient characteristics (race/ethnicity, income, and U.S. region of residence) influence disease severity at diagnosis, treatment rates, and time to treatment with ATTR-specific drugs of Medicare fee-for-service (FFS) patients with hereditary transthyretin amyloid-polyneuropathy (ATTRv-PN). 

Background:

ATTRv-PN is characterized by the deposition of amyloid throughout the body, including the nerves and heart. Timely diagnosis is important to maximize patients’ benefit from early access to novel disease-modifying therapies.  

Design/Methods:

This study used 2016-2023 Medicare FFS data from CMS 100% Research Identifiable Files to identify and characterize patients newly diagnosed with ATTRv-PN in 2018-2020, using ATTR-specific drugs and ICD-10-CM diagnosis codes. Enrollment information, claim types, and diagnosis, revenue, HCPCS, and NDC codes identified patient characteristics, including dual-eligibility for Medicare and Medicaid.   

Results:

Most patients had both peripheral nervous system and cardiac (mixed) involvement (mixed-90%; PN only-10%). Dual-eligible patients were diagnosed at a more severe stage (end-stage: dual-38%; non-dual-21%). ATTR-specific drug treatment rates varied by income and race/ethnicity. A higher proportion of non-dual-eligible and Black patients who were candidates for treatment received ATTR-specific drugs (dual-<16%; non-dual-43%; Black-51%; Non-Hispanic-White-35%; other-<28%), relatively evenly split between silencers and stabilizers. Time to treatment varied by income, with dual-eligible patients starting ATTR-specific drugs sooner (median months from diagnosis to treatment: dual-3.3; non-dual-3.7). Mean time to treatment was more than twice the median time in aggregate (months: mean-7.64; median-3.68), suggesting that some patients experience long delays. No notable differences in metrics were observed by geographic region.   

Conclusions:

Disease severity at diagnosis, ATTR-specific drug treatment rates, and time to treatment varied by race/ethnicity and income in patients with ATTRv-PN and treatment rates overall were low. Potential contributors for these findings include patient cost sharing, social determinants of health, and provider awareness. Further research is needed to understand the impact of these different factors on diagnosis and treatment to inform strategies to improve outcomes.