Impact of Anaemia on Management and Outcomes in Patients With Atrial Fibrillation: Insights From European and Asian Cohorts.

BACKGROUND

Anaemia is a common comorbidity in patients with atrial fibrillation (AF) receiving oral anticoagulants (OACs). While its relationship with bleeding is well established, the prothrombotic role and ethnic variations remain unclear.

METHODS

We analysed two large prospective AF registries from Europe (EORP-AF) and East Asia (APHRS-AF). Patients were classified by anaemia status at enrolment. Logistic regression assessed clinical correlates and treatment patterns, while multivariable Cox models and propensity score matching (PSM) evaluated outcomes. Restricted cubic spline analyses explored the haemoglobin-risk relationship across ethnic groups. The primary outcome was a composite of all-cause death and major adverse cardiovascular events (MACE); secondary outcomes included individual components and major bleeding (MB).

RESULTS

Among 10,857 patients with AF (mean age 69 ± 11 years, 40.0% women), 3372 (31.0%) had anaemia, which clustered with multimorbidity and frailty. Anaemic patients were less likely to receive OACs (OR 0.67, 95% CI 0.58-0.78) and rhythm-control (OR 0.91, 95% CI 0.81-1.02). Anaemia was independently associated with higher risk of the composite outcome (HR 1.54, 95% CI 1.34-1.78), all-cause death (HR 1.81, 95% CI 1.51-2.15), MACE (HR 1.39, 95% CI 1.16-1.66), CV death (HR 1.90, 95% CI 1.43-2.54) and MB (HR 1.79, 95% CI 1.31-2.46) consistent also after PSM. Risk increased progressively with anaemia severity, particularly below 10 g/dL. Associations were consistent across Asian and European cohorts.

CONCLUSION

Anaemia identifies a vulnerable AF phenotype associated with excess mortality, adverse cardiovascular outcomes and increased bleeding risk, which remains frequently undertreated. Risk rises with anaemia severity, and although biological effects appear consistent across ethnicities, treatment disparities persist. Anaemia should refine, not restrict, therapy within integrated AF care.