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

BACKGROUND AND IMPORTANCE: The Canadian Association of Emergency Physicians atrial fibrillation (AF) checklist advises that emergency physicians initiate anticoagulation therapy for patients with AF or flutter who are CHADS65 positive. OBJECTIVES: The aim was to compare anticoagulation initiation rates between patients treated with and without an anticoagulation assessment pathway (the SAFE pathway). DESIGN: This was a retrospective cohort study. SETTINGS AND PARTICIPANTS: All emergency department patients were discharged home with a diagnosis of AF between June 2018 and May 2020 at two Canadian emergency departments. INTERVENTION: The SAFE pathway is a hard copy form which allows emergency physicians to document contraindications to anticoagulation, the positive components of the CHADS65 score, and details how to prescribe anticoagulation. OUTCOME MEASURES AND ANALYSIS: Trained researchers abstracted data on the use of the SAFE pathway by the presence or absence of the completed, scanned pathway in the electronic medical chart. The exposure of interest was use of this pathway. Patients were followed forward in time for 90 days by electronic medical record review to document stroke, transient ischemic attack, arterial embolism and major bleeding events. All events were independently adjudicated. Adjusted odds ratios were calculated to compare outcomes between those managed with and without the SAFE pathway. RESULTS: In total, 766 patients were included, of whom 264 were already taking anticoagulation, 166 were CHADS65 negative and 65 had a contraindication to anticoagulation, leaving 271 patients eligible for anticoagulation prescription. Among the 271 eligible patients, 137/166 managed with the SAFE pathway were initiated on anticoagulation and 24/105 managed without the SAFE pathway started anticoagulation (adjusted odds ratio 25.9; 13.1-51.2). There was no statistically significant difference in the 90-day rate of stroke or bleeding. CONCLUSION: Use of the SAFE pathway was associated with a higher rate of anticoagulation prescription.