Warfarin Versus Non-Vitamin K Inhibitors Medications and Cognitive Disease Progression in Atrial Fibrillation

Atrial fibrillation (AF) is associated with cognitive decline. Use of oral anticoagulant (OAC) medications offers a lower risk of dementia, but it is unclear whether differences exist between types of OAC agents.

This was a secondary analysis to explore whether the progression from normal cognition to mild cognitive impairment to dementia differs between adults with AF on warfarin versus non-vitamin K inhibitor medications (NOACs) using data extracted from the National Alzheimer's Coordinating Center clinical case series.

Subjects with AF on OACs, having normal cognition and no stroke at baseline, and at least 1 follow-up visit were included. OAC usage was calculated based on follow-up time and reported previous OAC use. Continuation ratio models (with subject-specific random intercepts) were used to examine the association between OAC type and cognitive diagnosis controlling for cognitive diagnosis from previous visit.

Among 1475 eligible participants, 478 reported taking warfarin (n = 396) or NOACs (n = 82) at baseline (mean age of 79 years, 51% females, 84% non-Hispanic White). The median follow-up time was 4 years (interquartile range, 2-7). About 63% continued using either warfarin or NOACs, 44% switched from warfarin to NOACs, and 2% switched from NOACs to warfarin. After adjusting for age, sex, education, race, and cardiovascular clinical comorbidities, no significant association was found between OAC type and cognitive decline ( P = .14).

We found similar risks of cognitive decline between those on NOACs or warfarin. Future studies should consider effects of age, length of time from AF diagnosis, and OAC adherence on this risk.