Oral Anticoagulant Initiation in Patients With Kidney Failure on Hemodialysis Newly Diagnosed With Atrial Fibrillation (2007-2020): An Observational Study of Trends and Disparities

Rationale & Objective: Atrial fibrillation (AF) is common in patients with kidney failure on hemodialysis (HD), but few patients receive oral anticoagulant (OAC) treatment. Availability of direct-target OACs starting in 2010 may have induced greater OAC initiation, but this has not been systematically studied. Study Design: Retrospective cohort study. Setting & Participants: Using Medicare fee-for-service billing claims (2006-2020), we identified previously OAC-naïve HD patients newly-diagnosed with AF between January 1, 2007, and October 1, 2020. Exposures: Calendar year; race/ethnicity. Outcomes: OAC initiation within 90 days from AF diagnosis (any; specific agent). Analytical Approach: We estimated initiation risk ratios for each calendar year compared with the referent cohort, 2007, using unadjusted and multivariable-adjusted modified Poisson regression. We also determined differences by racial/ethnic group in OAC initiation, as well as any changes in these disparities over time. Limitations: Lack of clinical detail to firmly establish contraindications to OAC initiation. Conclusions: While rates of OAC initiation among patients on HD with newly-diagnosed AF increased in recent years, predominantly driven by increased use of apixaban, OAC initiation rates remained low, at 34% of patients in 2020. Compared with non-Hispanic White patients, OAC initiation remained consistently lower in patients of other race and ethnic groups.