Clinical outcomes of Asian patients with newly diagnosed atrial fibrillation and previously diagnosed atrial fibrillation: Insights from the CODE-AF registry

Heart Rhythm. 2024 Oct 24:S1547-5271(24)03507-0. doi: 10.1016/j.hrthm.2024.10.046. Online ahead of print.

Abstract

Background: Atrial fibrillation (AF) may have different clinical features in its early phase.

Objective: This study compared the characteristics and clinical outcomes of early-phase AF with later-phase AF using a large multicenter prospective registry (COmparison study of Drugs for symptom control and complication prEvention of Atrial Fibrillation [CODE-AF]).

Methods: Patients enrolled between June 2016 and March 2021 were divided into two groups based on AF duration: (1) newly diagnosed (AF duration ≤90 days) and (2) previously diagnosed (AF duration >90 days). The baseline characteristics and clinical outcomes were compared.

Results: Among the 10,001 study participants (mean age 67.0±14.5 years, and 64% men), 22% were defined as newly diagnosed and 78% as previously diagnosed. Newly diagnosed patients had fewer comorbidities and more unhealthy social behaviors. Despite lower prescription rates of oral anticoagulant, direct oral anticoagulants were more frequently used. The newly diagnosed group also had a higher composite clinical outcome risk within 90 days (adjusted HR 1.81, 95% CI 1.30-2.53, P<0.001) and revealed a higher risk of all bleeding and heart failure admission within 90 days. No significant differences remained between the groups over a 36-month follow-up.

Conclusions: Patients with early-stage AF were younger and had fewer comorbidities. While there was a higher risk of heart failure admissions and minor bleeding, the risk of death, stroke, and major bleeding was not significantly increased. Structured monitoring and management during the initial months are essential to address these risks.

Keywords: atrial fibrillation; bleeding; death; heart failure; stroke.