Abstract P364: Gender Differences in Long-Term Survival Following Isolated Coronary Artery Bypass Graft Surgery

Background: The current aging of the United States population and of the Western World is expected to increase the number of women undergoing isolated coronary artery bypass grafting (CABG). The literature consistently reports higher in-hospital mortality and morbidity in women undergoing isolated CABG. However, little has been done to determine the effect of gender on post-CABG long-term survival. Methods and Results: Survival was assessed in a cohort of 8,071 consecutive patients (28% were women) who underwent isolated CABG at Baylor University Medical Center, Dallas, TX between 1/1/1997-12/31/2008. Ten-year unadjusted survival was 55.6% [52.8%, 58.4%] in women and 64.3% [62.6%, 65.9%] in men. The unadjusted Hazard Ratio (HR) was 1.33 (95% Confidence Intervals [95%CI]: 1.22, 1.46) indicating a significantly higher risk of death in women. A propensity-adjusted model controlling for pre-operative risk factors identified by the Society of Thoracic Surgeons and other pre-operative clinical/non-clinical details was used to investigate the adjusted association between gender and post-CABG long-term mortality. After adjustment, the risk of death was not significantly higher in women than men (HR = 1.09; 95%CI: 0.97, 1.23) (see Figure). Conclusions: This study provides evidence that after controlling for pre-operative severity of disease and other possible confounders, risk of long-term mortality in women is not significantly higher than in men. Accordingly, women undergoing isolated CABG seem to be more likely to have important pre-operative comorbid conditions compared to men.