Stroke and Bleeding Risks in Atrial Fibrillation Are Not Static but Dynamic: A Dynamic Assessment of CHA2DS2-VASc and HAS-BLED Scores in the Iranian Registry of Atrial Fibrillation (IRAF)

Abstract

Background and Objectives: Proper stroke and bleeding risk assessment is an essential part of clinical decision-making in patients with atrial fibrillation (AF). This study aims to determine whether the dynamic assessment of CHA2DS2-VASc and HAS-BLED scores over time enhances stroke and bleeding risk prediction. Methods: In this prospective longitudinal study—based on data from the Iranian Atrial Fibrillation Registry (IRAF)—patients with available CHA₂DS₂-VASc and HAS-BLED scores at baseline, first follow-up (after 6 months), and second follow-up (after 12 months) were included. Univariable and multivariable logistic regression analyses were performed to evaluate the association of CHA₂DS₂-VASc and HAS-BLED scores (i.e., scores at baseline, first follow-up, and their difference defined as delta) with stroke and bleeding risk, respectively. Results: A total of 529 patients (mean age 61.2 ± 14.3 years; 59.7% male) were included. CHA₂DS₂-VASc and HAS-BLED scores increased significantly after 6 and 12 months from recruitment. delta CHA₂DS₂-VASc score (AUC 0.69; 95% CI: 0.54–0.84) and First follow-up CHA₂DS₂-VASc score (AUC 0.70; 95% CI: 0.51–0.88) achieved higher AUCs compared to baseline CHA₂DS₂-VASc score (AUC 0.63; 95% CI: 0.44–0.82). delta HAS-BLED score had the highest AUC (AUC 0.73; 95% CI: 0.55–0.91) compared to baseline (AUC 0.58; 95% CI: 0.43–0.74) and first follow-up HAS-BLED (AUC 0.60; 95% CI: 0.44–0.80) scores. Conclusions: Regular reassessment of CHA₂DS₂-VASc and HAS-BLED scores is essential in AF patients, as stroke and bleeding risks change over time, emphasizing the need for dynamic risk stratification.