Female sex as an independent predictor of high bleeding risk among East Asian percutaneous coronary intervention patients: A sex difference analysis

Background: Sex differences in the outcomes following percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) have been identified in Western countries. However, data on the long-term outcomes for bleeding events, particularly in East Asia where the aging population is growing rapidly and consists predominantly of women, remain scarce. Methods: We analyzed 2,494 ACS survivors from a multicenter PCI registry who underwent PCI between 2009 and 2012. The primary outcome was readmission for major bleeding at 2 years. Survival curves were generated with the cumulative incidence function. The adjusted hazard ratios were evaluated for the primary outcomes by sex using (1) Fine-Gray models and (2) Cox regression models. Results: There were 548 women (22.0%) in this cohort. The women were older (73.7 ± 10.8 years vs. 65.4 ± 11.8 years, p < 0.001), had a lower body mass index (23.0 ± 3.9 vs. 24.3 ± 3.6, p < 0.001), and had more comorbidities such as renal failure (49.4% vs. 36.3%, p < 0.001) and previous heart failure (8.4% vs. 4.5%, p < 0.001). Fewer women were discharged with statins (81.9% vs. 86.5%, p = 0.025) or beta blockers (70.6% vs. 77.1%, p = 0.007). During the 2-year follow-up, the unadjusted readmission rates for bleeding were higher among women (4.9% versus 2.4% at 2 years after discharge). Multivariable competing risk analysis with the Fine-Gray model and Cox regression model further demonstrated that female sex was associated with a higher risk of bleeding. Conclusions: Among patients treated with PCI, women had a higher incidence of bleeding events requiring readmission. Sex disparities in the etiologies of readmission following PCI suggest the need for targeted treatment strategies. A strict follow-up after discharge could be beneficial for women to further reduce their risk.