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Published on: February 26, 2013
Factors Influencing Oral Anticoagulation Prescription for Patients Presenting to Emergency Departments With Atrial
Robert J H Miller1, Derek S Chew1, Saman Rezazadeh1
1Libin Cardiovascular Institute of Alberta, Department of Cardiac Sciences, University of Calgary, Calgary, Alberta, Canada.
Insights
Oral anticoagulation (OAC) is underutilized in patients with atrial fibrillation/atrial flutter (AF/AFL) presenting to emergency departments. Hospitalization and AF/AFL as a primary diagnosis significantly increased OAC initiation rates.
Area of Science:
- Cardiology
- Emergency Medicine
- Pharmacology
Background:
- Atrial fibrillation/atrial flutter (AF/AFL) significantly elevates stroke and systemic embolism risk.
- Guideline-recommended oral anticoagulation (OAC) is often underprescribed in eligible AF/AFL patients.
- Emergency departments are critical points for initiating OAC in at-risk populations.
Purpose of the Study:
- To identify factors associated with oral anticoagulation (OAC) initiation in eligible patients presenting to emergency departments with electrocardiogram (ECG)-documented atrial fibrillation/atrial flutter (AF/AFL).
- To evaluate OAC prescription rates within 90 days of emergency department (ED) presentation for guideline-eligible patients not previously on OAC.
Main Methods:
- Retrospective cohort study of 4948 patients with ECG-documented AF/AFL across 4 urban EDs in 2015.
- Chart review to determine presenting diagnoses, admission status, and comorbidities (CHADS-65 score).
- Analysis of OAC prescription within 90 days of ED presentation for 2059 eligible patients.
Main Results:
- Only 32.2% of eligible patients received OAC within 90 days of ED presentation.
- Hospitalization (OR 1.31), AF/AFL as the primary diagnosis (OR 4.56), and higher CHADS-65 scores (OR 1.14 per point) were associated with increased OAC initiation.
- No association was found with individual CHADS-65 score components.
Conclusions:
- Guideline-directed OAC is infrequently initiated in eligible AF/AFL patients post-emergency department visit.
- Hospitalization and AF/AFL being the primary diagnosis are key drivers for OAC initiation.
- Novel interventions are necessary to improve appropriate OAC prescribing for AF/AFL patients.
Abstract:
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.
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