Abstract 337: Gender Differences and Outcome After Isolated Coronary Artery Bypass Grafting: A Systematic Review and Meta-analysis

Abstract
Background: Coronary artery bypass grafting (CABG) is among the most common surgical procedures performed in developed nations. In spite of this, studies have reported gender differences in clinical outcome exist in outcome after CABG. As data is limited to observational studies, we performed a systematic review to compare CABG outcome between women and men. Methods: We queried databases (1 st January 2000 - 20 th January 2020) to identify original studies comparing CABG outcome between genders. Our aims were (1) to study differences in risk factors (2) to compare early mortality, stroke, wound infection, acute kidney injury rates and long-term survival. We pooled risk ratios (RR) with inverse variance weighting and a random effects model for early end-points. Long-term survival was compared using incident risk ratios (IRR). All results are presented with their 95% confidence interval. Results: We identified 24 observational studies (1,647,035 women and 3,642,057 men) from 13 countries for inclusion. At time of CABG, women were older (66 vs 64 years; p < 0.01) and had a higher incidence of diabetes mellitus (32% vs 24%; p < 0.01), congestive heart failure (12% vs 8%; p < 0.01) and emergent surgery (13% vs 9%). More men had left ventricular dysfunction (12% vs 10%; p < 0.01) and prior myocardial infarction (40% vs 37%). Women received fewer grafts (mean difference -0.22; p < 0.01) and arterial conduits (OR 0.51, CI 0.41 - 0.63; p < 0.01). Early mortality (4% vs 2.5%, OR 1.5, CI 1.4 - 1.7) and stroke rates (OR 1.9, CI 1.3 - 1.7) were higher in women. Sternal wound infection (4.7% vs 2%) was also higher in women (OR 1.8, CI 1.1 - 1.8, p = 0.001). Acute kidney injury (OR 1.1, p = 0.09) and long-term survival (IRR 0.9, CI 0.8 - 1.2, p = 0.9) are comparable. Conclusion: Our meta-analysis demonstrates that women and men have significant differences in presentation and outcome after CABG. While women have worse post-operative outcomes, long-term survival is comparable.