Clinical Complexity Domains, Anticoagulation, and Outcomes in Patients with Atrial Fibrillation: A Report from the GLORIA-AF Registry Phase II and III

Background: Clinical complexity is common in atrial fibrillation (AF) patients. We assessed the impact of clinical complexity on oral anticoagulant (OAC) treatment patterns and major adverse outcomes in a contemporary cohort of AF patients. Methods: The GLORIA-AF Phase II and III Registry enrolled newly diagnosed AF patients with at least one stroke risk factor. Among patients with CHA2DS2-VASc score ≥2, we defined four domains of perceived clinical complexity: frail elderly (age ≥75 years and body mass index <23 kg/m2), chronic kidney disease (CKD, creatinine clearance <60 mL/min), history of bleeding, and those with ≥2 of the above conditions. We evaluated the associations between clinical complexity domains and antithrombotic treatment prescription, risk of OAC discontinuation, and major adverse outcomes. Results: Among the 29,625 patients included (mean age 69.6 ± 10.7 years, 44.2% females), 9,504 (32.1%) presented with at least one complexity criterion. Clinical complexity was associated with lower OAC prescription, with stronger associations in frail elderly (odds ratio [OR]: 0.47, 95% confidence interval [CI]: 0.36-0.62) and those with ≥2 complexity domains (OR: 0.50, 95% CI: 0.44-0.57). Risk of OAC discontinuation was higher among frail elderly (hazard ratio [HR]: 1.30, 95% CI: 1.00-1.69), CKD (HR: 1.10, 95% CI: 1.02-1.20), and those with ≥2 complexity domains (HR: 1.39, 95% CI: 1.23-1.57). Clinical complexity was associated with higher risk of the primary outcome of all-cause death, thromboembolism, and major bleeding, with the highest magnitude in those with ≥2 criteria (HR: 1.63, 95% CI: 1.43-1.86). Conclusion: In AF patients, clinical complexity influences OAC treatment management, and increases the risk of poor clinical outcomes. These patients require additional efforts, such as integrated care approach, to improve their management and prognosis.