Evolving Mechanisms on Mortality in Atrial Fibrillation: A 25‐Year National Death‐Certificate Analysis

ABSTRACT Background Atrial fibrillation (AF) prevalence has risen alongside an aging US population and wider adoption of contemporary therapies, yet population‐level changes in mechanisms of death among people with AF remain incompletely characterized. We used National Death Certificate Trends in AF Mortality data to assess 25‐year trends in AF‐related mortality and the contribution of heart failure (HF), stroke, myocardial infarction (MI), and dementia. Methods We conducted a retrospective analysis of CDC WONDER records for US decedents aged ≥ 35 years with AF listed as a contributing cause of death from 1999 to 2023, coinciding with the implementation of ICD‐10 coding in the CDC database. We quantified all‐cause and cause‐specific mortality rates per 100 000 and stratified trends by age, sex, and race. The analytic cohort included decedents with AF and at least one of four cardiovascular conditions (stroke, dementia, HF, or MI) listed as a primary or contributing cause of death. Confidence intervals were obtained from CDC WONDER outputs or calculated per CDC guidance. Results Among 3 273 015 decedents with AF noted on the death certificate, 461 321 had HF, dementia, stroke, or MI listed as a contributing cause. HF emerged as the leading cause/contributor with a steep rise beginning in approximately 2008. Stroke rates were stable or declining, MI‐related mortality remained low and stable, while dementia, particularly stroke‐free dementia, increased significantly in adults ≥ 85 (outpacing stroke among the oldest White decedents since early 2000s). Non‐White groups exhibited higher stroke and HF mortality trends; women ≥ 85 had higher stroke‐related mortality than men. Conclusions Over 25 years, AF‐associated mortality patterns shifted toward HF and stroke‐free dementia while ischemic stroke and MI declined or stabilized. Findings highlight the need to expand AF care beyond stroke prevention to prioritize HF prevention/management, cognitive health, equitable AF‐care pathways to ensure broad access to therapies, and additional studies of targeted interventions to mitigate disease risks.