AHA Scientific Sessions 2026 Abstract · Nov 2, 2026
Sex Differences in Stroke Following Incident Atrial Fibrillation: An ITHACA Database Study
By Coleman K, Sullivan I, Miller L et al.
Background: Female sex is incorporated into contemporary thromboembolic risk stratification schemes for atrial fibrillation (AF), yet the temporal relationship between AF diagnosis and stroke among women and men remains incompletely characterized. Objective: To evaluate the association between sex and stroke occurring after incident AF diagnosis in a large integrated healthcare system. Methods: This was a retrospective cohort study of patients with incident AF in the highly diverse population of Northwell Health, the largest healthcare system in the Northeastern United States (2015- 2025). Stroke events were classified according to their timing relative to AF diagnosis as occurring before, on the same date, or after AF diagnosis. The primary outcome was incident stroke occurring after AF diagnosis. Multivariable logistic regression was performed to evaluate the association between female sex and post-AF stroke after adjustment for age, comorbidity burden, race, and ethnicity. Predicted probabilities of post-AF stroke were estimated across the age spectrum. Results: Among 153,208 patients with available follow-up [median 3.6 years] after incident AF diagnosis, 8,077 (5.3%) experienced stroke following AF diagnosis. Women had a higher incidence of post-AF stroke compared with men (5.9% vs. 4.7%, p<0.001). Patients who experienced post-AF stroke were older at diagnosis (median age 75 [IQR 67-81] vs. 73 [64-80] years, p<0.001) and had greater comorbidity burden (Charlson Comorbidity Index 5 [IQR 3-7] vs. 2 [1-4], p<0.001). Female sex remained independently associated with post-AF stroke after adjustment for age, race, ethnicity, and comorbidity burden (adjusted OR 1.24, 95% CI 1.18-1.31, p<0.001). Among patients who developed post-AF stroke, the median time from AF diagnosis to stroke was similar between women and men (672 [199-1495] vs. 675 [203-1577] days, p=0.40). Adjusted predicted probabilities demonstrated consistently higher stroke risk among women across the age spectrum. Conclusion: In this large, diverse health-system cohort, women experienced a significantly higher risk of stroke following AF diagnosis. Female sex remained independently associated with post-AF stroke after multivariable adjustment, while the timing of stroke occurrence following AF diagnosis was similar between sexes.