Factors Influencing Oral Anticoagulation Prescription for Patients Presenting to Emergency Departments With Atrial Fibrillation and Flutter

Atrial fibrillation and atrial flutter (AF/AFL) are associated with an increased risk of stroke and systemic embolism. However, many patients are not started on guideline-recommended oral anticoagulation (OAC). We determined factors associated with initiation of OAC in eligible patients presenting to emergency departments. This retrospective cohort included patients with electrocardiogram (ECG)-documented AF/AFL presenting to 4 urban emergency departments in 2015. Presenting diagnoses, admission status, and comorbidities were determined by chart review. The primary outcome was OAC prescription within 90 days of ED presentation in guideline-eligible patients not previously on OAC. Of 4948 patients presenting to emergency departments with ECG-documented AF/AFL, we identified 2059 patients with Congestive Heart failure, Age (≥65),Diabetes, and Stroke (CHADS-65) score ≥1 not previously on OAC. Of those patients, 1287 (62.5%) were admitted, and 772 (37.5%) were discharged from the emergency department. Within 90 days of discharge, 663 (32.2%) patients were initiated on OAC. On multivariable analysis, hospitalization (odds ratio [OR] 1.31; 95% confidence interval [CI] 1.05-1.63, P = 0.02), presenting diagnosis of AF/AFL (OR 4.56, 95% CI 3.60-5.79, P < 0.01), and higher CHADS-65 score (OR 1.14 per point, 95% CI 1.04-1.25, P < 0.01) were associated with increased rates of OAC initiation. However, there was no association with individual components of the CHADS-65 score. Guideline-directed OAC is infrequently initiated in eligible patients within 90 days of presenting to emergency departments. The strongest factors associated with OAC initiation rates were hospitalization or having primary presenting diagnoses in emergency departments of AF/AFL after adjusting for other important characteristics. New interventions are required to improve appropriate OAC initiation in patients with AF/AFL.