Association of Gender With Clinical Outcomes in a Contemporary Cohort of Patients With Atrial Fibrillation Receiving Oral Anticoagulants

Abstract

Background and objectives: In patients with atrial fibrillation (AF), females taking vitamin K antagonist are at higher risk of stroke or systemic embolism (SSE), bleeding and all-cause death than males. This study investigated the relationship between sex and adverse clinical events in a contemporary AF patient cohort taking anticoagulation.

Methods: This prospective multicenter AF registry study comprised 6,067 patients with AF (mean age, 70±9 years; men, 59%) with intermediate to high risk of stroke (CHA₂DS₂-VAscore ≥1) and receiving oral anticoagulation therapy. Adverse clinical outcomes, including SSE, bleeding, death were evaluated in patients stratified by sex and anticoagulation patterns.

Results: Women were older and used more direct oral anticoagulants (85% vs. 78%, p<0.001) than men. During a median (25^th and 75^th percentiles) follow-up of 30 (24, 38) months, the incidence rate and risk of SSE (0.7 in women vs. 0.7 in men per 100 person-years) and major bleeding (0.1 in women vs. 0.1 in men per 100 person-years) were not different between the sexes. However, women had a lower all-cause death rate (0.4 in women vs. 0.6 in men per 100 person-years, hazard ratio: 0.48, 95% confidence interval: 0.25-0.91, p=0.025) than men.

Conclusions: In contemporary anticoagulation for AF, SSE and major bleeding risks did not differ between sexes. However, women showed a lower risk of all-cause death rate than men, indicating that the use of oral anticoagulants for treating AF in females does not appear to be a risk factor for adverse clinical events.

Trial registration: ClinicalTrials.gov Identifier: NCT02786095.

Keywords: Anticoagulants; Atrial fibrillation; Female.

Figure 1. Cumulative incidence of stroke or systemic embolism (A), major bleeding (B), and all-cause death (C).

Figure 2. Forest plot representation of clinical factors including anticoagulation associated with the primary endpoint (stroke or systemic embolism).

CI = confidence interval; DOAC = direct oral anticoagulant; HR = hazard ratio; HTN = hypertension; MI = myocardial infarction; TIA = transient ischemic attack; VKA = vitamin K antagonist.