Log in to MyACC
Ischemic Stroke in Women With Atrial Fibrillation
Quick Takes
- Female sex is traditionally considered an additive risk factor for ischemic stroke and systemic embolism for patients with AF.
- In a Finnish nationwide cohort study, the risk of ischemic stroke declined over an 11-year period.
- By 2018, there was no difference in the risk of ischemic stroke between women and men with AF, suggesting that sex may no longer be a relevant stroke risk factor.
Study Questions:
What are the temporal trends in ischemic stroke risk associated with female sex for patients with atrial fibrillation (AF)?
Methods:
The authors used the registry-linked FinACAF (Finnish AntiCoagulation in Atrial Fibrillation) study of all patients with AF in Finland between 2007 and 2018 to explore the rates of ischemic stroke. They compared rates between men and women over time and between various risk groups.
Results:
The study included 229,565 patients with new-onset AF, of whom 50.0% were women (mean age 72.7 years). The crude incidence of ischemic stroke was higher in women than in men across the entire study period (21.1 vs. 14.9 events/1,000 patient-years, p < 0.001). The incidence of ischemic stroke declined for both women and men during the study period, decreasing from a 20-30% increased risk for women in 2007-2008 to a nonsignificant risk difference by 2018. The decline in overall stroke risk difference between women and men was driven by a decline in stroke risk for women with ≥1 non-sex stroke risk factor (i.e., CHA2DS2-VASc score ≥2).
Conclusions:
The authors conclude that the association between female sex and ischemic stroke risk has decreased and become nonsignificant between 2007 and 2018. The authors conclude that female sex could be omitted as a stroke risk factor when determining the need for oral anticoagulant use in AF.
Perspective:
Since the introduction of the CHA2DS2-VASc stroke risk score in 2010, female sex has been considered an additive risk factor for patients with AF. However, this sex-based risk was defined on decades-old data from patients with AF and may no longer apply for patients in the current era with a different risk profile. This study of all AF patients in Finland suggests that sex is no longer a significant stroke risk factor, having lost its predictive ability in 2011-2012. While this finding needs to be confirmed in other populations, especially those with different socioeconomic, demographic, and comorbidity profiles, further research is needed to better understand why this change has occurred over the past 11 years. It is plausible that the changing use of tobacco, obesity, diabetes, and other risk factors in both men and women could be “leveling the playing field” in AF-related stroke risk between men and women. While clinicians should continue to use female sex as an additive AF-related stroke risk factor in the CHA2DS2-VASc score for now, future replication of these results may change the way in which we approach risk stratification in the coming years.
Clinical Topics: Arrhythmias and Clinical EP, Atrial Fibrillation/Supraventricular Arrhythmias, Anticoagulation Management and Atrial Fibrillation, Vascular Medicine
Keywords: Atrial Fibrillation, Ischemic Stroke
< Back to Listings
