Background The magnitude of increased risk of stroke in women with atrial fibrillation (AF) remains uncertain. Hypothesis We investigated the risk of ischemic stroke and death in women and men with AF, and the risk associated with individual non‐sex CHA2DS2‐VASc risk factors. Methods Retrospective cohort study of 231 077 (48.1% women) nonselected patients with AF not receiving oral anticoagulation from 2006 to 2014. Data from cross‐linked national Swedish registers. The outcome was the first occurrence of ischemic stroke or death. Median age was 82 and 75 years in women and men, respectively. Mean follow‐up was 2.5 years. Results Hazard ratios, adjusted for non‐sex CHA2DS2‐VASc risk factors, for women vs men were 1.53, 95% CI: 1.49‐1.58 for ischemic stroke and 1.24, 95% CI: 1.22‐1.26 for death, respectively. When divided into age groups the differences in ischemic stroke rates between women and men were attenuated. In patients with only one non‐sex CHA2DS2‐VASc risk factor allotted 1 point, ischemic stroke rates per 100 person‐years were 1.22 in women (n = 9838) and 1.02 in men (n = 15 609), respectively, P < .006. In both women and men, age of 65 to 74 years was associated with higher ischemic stroke risk compared to other non‐sex CHA2DS2‐VASc risk factors allotted 1 point. Conclusions The risk of ischemic stroke was 1.5‐fold higher in women compared to men but this association appears to be the result of confounding by age. In the low risk end, the CHA2DS2‐VASc risk score underestimates the ischemic stroke risk conferred by age 65 to 74 years, while it overestimates the risk conferred by female sex.

No abstract

No abstract

No abstract

Background: NT-proBNP is elevated in patients with a diagnosis of atrial fibrillation (AF) and associated with risk of stroke and other outcomes. The associations have mainly been studied in patients on oral anticoagulation and not considering if samples were obtained during AF or sinus rhythm. We investigated the association of NT-proBNP with heart rhythm and cardiovascular (CV) events in patients with AF without oral anticoagulation. Methods: Plasma samples were obtained at baseline in 3184 patients with diagnosis of AF (2142 in AF rhythm at blood sampling) receiving aspirin in two multicenter randomized clinical trials with median follow-up 1.2 years (AVERROES) and 3.8 years (ACTIVE A), respectively. NT-proBNP was analyzed using Elecsys electrochemiluminescence immunoassay. Association of NT-proBNP with clinical variables was assessed with multivariable linear regression models. Association with outcomes were estimated with Cox-regression models adjusting for clinical variables. Results: Median age was 71 years, 57.8% were men, and median NT-proBNP 713 ng/L (25 th -75 th percentiles, 282-1388 ng/L). Variables contributing to NT-proBNP level were, in reducing order: AF rhythm (ratio of geometric means 2.9), age, creatinine, and prior heart failure. Levels of NT-proBNP were significantly associated with ischemic stroke (HR 3 rd vs 1 st quartile 2.1, 95%CI 1.5-3.0), heart failure hospitalizations (HR 2.2, 95%CI 1.6-2.9), and CV death (HR 2.4, 95% CI 1.8-3.3), all p<0.001, without significant interaction with AF rhythm. Figure depicts NT-proBNP distribution by rhythm and association with ischemic stroke. Conclusion: In patients with a diagnosis AF, plasma levels of NT-proBNP are three times higher during AF rhythm compared with sinus rhythm. Higher levels of NT-proBNP are independently associated with ischemic stroke, heart failure hospitalizations, and CV death in AF patients without oral anticoagulation treatment, irrespective of heart rhythm.