Is Female Gender Associated with Mortality in Coronary Artery Bypass Grafting?

Background: Women undergoing coronary artery bypass grafting (CABG) tend to have worse in-hospital outcomes, but it is unclear whether these differences are due to gender or to clinical factors. Objective: To compare in-hospital outcomes between women and men undergoing CABG. Methods: This was a single-center, retrospective observational study analyzing data from 9,845 patients who underwent CABG between 1995 and 2022, of whom 1,947 (19.8%) were women. To evaluate female gender as a prognostic factor for in-hospital mortality, we used descriptive statistics, univariate and multivariate logistic regression, and propensity score matching. The significance level was set at 5%. Results: Women were older (66.7 vs 62.19 years, p<0.001), had lower body mass index (26.91 vs 27.64, p<0.001), and had a higher prevalence of diabetes mellitus (34.0% vs 31.6%, p=0.045). They also had longer hospital stays (14.84 vs 13.13 days, p<0.001) and higher operative mortality (4.8% vs 2.4%, p<0.001). In logistic regression, female gender was associated with higher mortality (OR=1.51; 95% CI: 1.15-1.99; p=0.003). After matching, there was no significant difference in mortality (OR=1.20; 95% CI: 0.88-1.64; p=0.241), but length of hospital stay remained longer in women. Conclusion: When clinical factors were matched between men and women, the mortality difference disappeared. This suggests that targeted interventions to reduce disparities may help improve mortality outcomes in women undergoing CABG.