Trends in Uptake and Adherence to Oral Anticoagulation for Patients With Incident Atrial Fibrillation at High Stroke Risk Across Health Care Settings

Abstract

Background Oral anticoagulation (OAC) therapy prevents morbidity and mortality in nonvalvular atrial fibrillation; whether location of diagnosis influences OAC uptake or adherence is unknown. Methods and Results Retrospective cohort study (2008–2019), identifying adults with incident nonvalvular atrial fibrillation across health care settings (emergency department, hospital, outpatient) at high risk of stroke. OAC uptake and adherence via proportion of days covered for direct OACs and time in therapeutic range for warfarin were measured. Proportion of days covered was categorized as low (0–39%), intermediate (40–79%), and high (80–100%). Warfarin control was defined as time in therapeutic range ≥65%. All‐cause mortality was examined at a 3‐year landmark. Among 75 389 patients with nonvalvular atrial fibrillation (47.0% women, mean 77.4 years), 19.7% were diagnosed in the emergency department, 59.1% in the hospital, and 21.2% in the outpatient setting. Ninety‐day OAC uptake was 51.6% in the emergency department, 50.9% in the hospital, and 67.9% in the outpatient setting ( P <0.0001). High direct OAC adherence increased from 64.9% to 80.3% in the emergency department, 64.3% to 81.7% in the hospital, and 70.9% to 88.6% in the outpatient setting over time ( P values for trend <0.0001). Warfarin control was 40.3% overall and remained unchanged. In multivariable analysis, outpatient diagnosis compared with the hospital was associated with greater OAC uptake (odds ratio [OR], 1.79; [95% CI, 1.72–1.87]) and direct OAC (OR, 1.42; [95% CI, 1.27–1.59]) and warfarin (OR, 1.49; [95% CI, 1.36–1.63]) adherence. Varying or persistently low adherence was associated with a poor prognosis, especially for warfarin. Conclusions Locale of nonvalvular atrial fibrillation diagnosis is associated with varying OAC uptake and adherence. Interventions specific to health care settings are needed to improve stroke prevention.

Trends in Use of Oral Anticoagulants in Older Adults With Newly Diagnosed Atrial Fibrillation, 2010-2020

“… 27 In Alberta, Canada, 90-day initiation of OAC after incident AF in adults aged 18 years or older with CHA 2 DS 2 -VASc score greater than 2 in men and greater than 3 in women increased from 44% in 2008 to 67% in 2019. 28 The rate of OAC initiation in our study was comparatively lower, which likely reflects differences in health care utilization across widely different health care systems.…”

“…The professional guidelines have recommended all DOACs on an equal footing since their regulatory approval, 23 , 39 but apixaban has been clearly preferred by prescribers in both North America and Europe 12 , 28 , 40 for several reasons. 41 Dabigatran was the first DOAC to be approved for AF, but concerns regarding its bleeding risks limited its uptake, even after the US Food and Drug Administration approval of idaricuzimab in 2015.…”

Review article: diagnosis, pathophysiology and management of atrial fibrillation in cirrhosis and portal hypertension

“…This is the likely reason for low anticoagulation prescription rates in patients with AF and cirrhosis, ranging between 9.6% and 28.1% in registries. 5,64,75,76 A positive trend was noted by Han et al 5 with increasing anticoagulation prescription rates of 2.7% in 2003 to 13.6% in 2014. However, patients with cirrhosis are also at an increased risk of clotting with a 1.5-fold higher risk of stroke and a 1.7-fold higher risk of venous thromboembolisms.…”

“…Therefore, the increased bleeding complications in cirrhosis are not due to defective haemostasis but structural lesions with increased bleeding tendency, such as varices and portal hypertensive gastropathy. This is the likely reason for low anticoagulation prescription rates in patients with AF and cirrhosis, ranging between 9.6% and 28.1% in registries 5,64,75,76 . A positive trend was noted by Han et al 5 with increasing anticoagulation prescription rates of 2.7% in 2003 to 13.6% in 2014.…”

Anticoagulation prescription among atrial fibrillation patients managed with and without an anticoagulant initiation pathway: a cohort study

“…The CAEP atrial fibrillation checklist uses CHADS65 [the presence of heart failure, hypertension, age 65 or more, diabetes or prior stroke/transient ischemic attack (TIA)] to determine the need for anticoagulation, in line with the Canadian Cardiovascular guidelines [6]. We reviewed local practice, finding only 17% of new-onset AF patients eligible for anticoagulation were offered anticoagulation [7], much lower than the anticoagulation rates reported across our province of Ontario [1,8]. From there, we developed and implemented a standardized pathway for initiating anticoagulation in AF patients in the ED (called Safe Anticoagulation for Atrial Fibrillation in the Emergency: the SAFE pathway) [9].…”