Sex differences in how frailty affects treatment and outcomes in older adults with atrial fibrillation

Aims To examine the prevalence of frailty in older adults with atrial fibrillation (AF) and the association between frailty with oral anticoagulant (OAC) prescription and hospitalization, with a focus on variations by sex. Methods Adults aged ≥60 years with AF were recruited at two hospitals in Vietnam from 2022 to 2024. Frailty was defined by the Clinical Frailty Scale (CFS). Logistic regressions were conducted to examine the association between CFS with OAC prescription and cardiovascular‐related hospitalization over 6 months. Results are presented as odds ratios (ORs) and 95% confidence intervals (CIs). The women‐to‐men ratios of ORs and 95% CIs were calculated to quantify how the ORs differed between the sexes. Results There were 1210 participants (513 women, 697 men, mean age 74). The prevalence of frailty was 40.7% (46.8% in women vs . 36.3% in men, p < 0.001). With every unit increase in the CFS, the adjusted ORs for OAC prescription were 0.70 (95% CI 0.54–0.90) in women, 0.97 (95% CI 0.74–1.28) in men (women‐to‐men ratio of ORs 0.72, 95% CI 0.50–1.05). CFS score predicted cardiovascular‐related hospitalization: adjusted ORs 1.65 (95% CI 1.29–2.10) in women, 2.04 (95% CI 1.62–2.59) in men, women‐to‐men ratio of ORs 0.81 (95% CI 0.58–1.13). Conclusions Frailty was more common and was associated with reduced odds of receiving OAC in women. There was a trend of increased impact of frailty on cardiovascular‐related hospitalization in men compared to women. Further studies are needed to confirm these findings.