The Characterization of Atrial Fibrillation and Prognostic Value of a Modified 4S-AF Scheme: A Report from the REGUEIFA Community Health Area Registry (Galician Intercentric Registry of Atrial Fibrillation)

<b>Background:</b> The REGUEIFA registry aims to assess the contemporary treatment of patients with atrial fibrillation (AF) in the community health area of Galicia. Due to the prognostic relevance of anticoagulation status, we used it to differentiate patients by adding a category to the stroke domain of the 4S-AF score. <b>Methods:</b> A Cox proportional hazards analysis was used to identify the prognostic value of the modified 4S-AF score regarding mortality, cardiovascular mortality, and thromboembolic events. For bleeding events, we used a Poisson regression model to account for recurrent events. <b>Results:</b> When considering the stroke risk domain as a categorical variable, the risk stratification for all-cause mortality improved by more than 2 times (stroke risk: 2 vs. 1; hazard ratio (HR): 2.17; 95% confidence interval (CI): 1.03-4.55), <i>p =</i> 0.04). According to the Poisson regression model, the stroke risk domain was also an independent factor for hemorrhagic events (HR: 2.83; 95% CI 1.69-4.74, <i>p <</i> 0.001). For patients with permanent AF, the mortality rate was more than 2 times higher than that of patients with paroxysmal AF or their first episode of AF (HR: 2.53; 95% CI; 1.53-4.18); <i>p</i> < 0.001. Anticoagulation therapy was the only independent domain treatment associated with a reduction in all-cause mortality (HR: 0.41; 95% CI 0.19-0.89 <i>p <</i> 0.0023). <b>Conclusions:</b> The modification of the stroke risk score to reflect anticoagulation status may improve the characterization and stratification of overall mortality risk, as demonstrated in the contemporary AF cohort from the REGUEIFA study. The permanent form of AF was associated with a higher risk of overall mortality and cardiovascular mortality.