Patterns of oral anticoagulation use and adherence for atrial fibrillation from 2010-2020

1. This cohort study of older adults under the Medicare Advantage insurance plan demonstrated that from 2010 to 2020, there was a 12.7% increase in OAC initiation within 12 months of new AF diagnosis and a reduction of 13.2% in OAC nonadherence.

2. Older adults with anemia, frailty, dementia or a history of pelvic or hip fractures were disproportionately less likely to be initiated on OACs for new AF.

Evidence Rating Level: 2 (Good)

Study Rundown: Atrial fibrillation (AF) is prevalent among older adults, which increases the risk of cardioembolic stroke. The emergence of direct oral anticoagulants (DOACs) was thought to increase anticoagulant initiation and use among older adults, given their ease of use compared to warfarin. Changes in anticoagulation prescription patterns and adherence have yet to be studied since 2016. This retrospective cohort study assessed trends in recent oral anticoagulation (OAC) and DOAC use for new AF and patient characteristics associated with non-adherence. Administrative claims between January 1, 2010, and December 31, 2020, were analyzed to identify patients aged 65 years or older with AF. The primary outcomes were OAC initiation within 12 months of AF diagnosis and OAC nonadherence. From 2010 to 2020, there was a 12.7% increase in the proportion of patients prescribed OAC within a year of diagnosis of AF (OR for OAC initiation per year: 1.06 [95% CI: 1.06-1.07]). In addition, DOAC use increased from 1.1% to 30.9%, and warfarin use decreased from 19.1% to 2.0%. Factors significantly associated with reduced odds of OAC initiation included older age, dementia, frailty, anemia, and a history of pelvic or hip fracture. Conversely, a higher CHA₂DS₂-VASc score was associated with increased odds of initiating OACs. From 2010 to 2020, the proportion of OAC nonadherence decreased from 52.2% to 39.0%. Notably, apixaban was the most used DOAC (64.0%), followed by rivaroxaban (28.1%) and then dabigatran (7.8%). Overall, this cohort study assessing patterns of OAC use for individuals with AF demonstrated that OAC initiation has been improving in the past decade with increasing use of DOACs and decreasing use of warfarin. However, older individuals and those with dementia, frailty, anemia, or a history of pelvic/hip fracture were disproportionately at reduced odds of OAC initiation. This study was limited by only including adults under the Medicare Advantage (MA) insurance plan, which may not apply to all older adults with new AF.

Click to read the study in JAMA

Relevant Reading: Atrial fibrillation, stroke, and anticoagulation in Medicare beneficiaries: trends by age, sex, and race, 1992-2010

Image: PD

©2022 2 Minute Medicine, Inc. All rights reserved. No works may be reproduced without expressed written consent from 2 Minute Medicine, Inc. Inquire about licensing here. No article should be construed as medical advice and is not intended as such by the authors or by 2 Minute Medicine, Inc.