Abstract 17095: Change in Oral Anticoagulant Use for Atrial Fibrillation From 2013 to 2018 Among US Veterans and the Impact of Frailty

Introduction: Direct oral anticoagulants (DOACs) are superior to warfarin in both efficacy and safety regardless of frailty status. Data on prescribing patterns of different oral anticoagulants (OACs) in frail older adults are limited.

Methods: We utilized the Veterans Health Administration clinical data, to identify those aged 65 and older with a diagnosis of non-valvular atrial fibrillation (AF) who initiated anticoagulation in 2013 and 2018. Frailty was assessed using the 31-item VA Frailty Index (VA-FI). Patients were stratified into 3 categories. VA-FI: frail (frailty index >0.2), pre-frail (frailty index 0.11-0.2), and non-frail (frailty index 0-0.1). Baseline data on prior stroke, CHA ₂ DS ₂ -VASc score, and bleeding were extracted. Descriptive statistics and logistic regression were used to examine association of frailty with choice of OAC.

Results: Among 39,647 Veterans included from 2013 and 2018, mean age was between 71 to 76. 99% were male and 88% white race. From 2013 to 2018, DOACs use increased from 21% to 88%, while warfarin use decreased accordingly. Among the OACs, dabigatran was dominant (65%) in 2013 but apixaban was dominant (66%) in 2018. Increasing frailty was associated with reduced use of DOACs (p<0.001 in 2013 and 2018). Regardless of the choice of drug, the prior bleeding and prior stroke/transient ischemic attack were mostly seen in the frail population ranging between 54-60% and 20-21% respectively. CHA ₂ DS ₂ -VASc score averaged 3 for non-frail, and 4 for prefrail and frail patients regardless of the year. (Figure)

Conclusion: Prior bleeding and stroke episodes were more common among the frail population. There was significant reduction in use of DOACs in both years with increasing frailty. Studying the impact of anticoagulant choice on clinical outcomes among frail older adults with non-valvular AF are needed.