Abstract MP24: Women Experience Higher Rates of Surgical Repair and Mortality for Abdominal Aortic Aneurysm

Abstract

Background: It is unknown how gender disparities in the clinical presentation of abdominal aortic aneurysm (AAA) affects AAA repair type and long-term survival. We assessed the hypothesis that compared to men, women face a higher risk of death after AAA repair due to differences in demographics, disease severity, and repair type. Methods: We analyzed all endovascular (EVAR) and open surgical (OPEN) AAA repairs from 2003-2015 in the Vascular Quality Initiative-Medicare linked registry. Using inverse probability weighting, we balanced patient demographics, comorbidities, and disease severity among men and women. Then, we evaluated the effect of gender on AAA treatment and subsequent survival using Poisson and Cox regression, respectively. Results: In this cohort (n=16,085), patients undergoing EVAR (79%) or OPEN (21%) had up to 12 years of follow-up. Women comprised 22% of the cohort and were older (mean age 77 ±6.6 vs. 75 ±6.5 years, p<0.001), less likely to smoke (28% vs. 33%, p<0.001), and had smaller aneurysms (58.7 ±18.5 mm vs 56.5 ±12 mm) than men (Figure). After balancing key risk factors, women were 1.6 times more likely to receive OPEN vs. EVAR (RR: 1.59, 95% CI: 1.46-1.72). The 12-year mortality rate after AAA repair was 74% in men vs 84% in women. After adjustment, women faced a 12% increased risk of death (HR: 1.12, 95% CI: 1.04-1.21). Sub-analysis by repair type revealed a gender discrepancy among EVAR patients, where women experienced poorer survival (HR: 1.18, 95% CI: 1.09-1.29), while men and women faced an equal risk of death after OPEN (HR: 1.00, 95% CI: 0.90-1.12). Conclusion: In conclusion, women were 1.6 times more likely to undergo OPEN repair than men, despite balancing key baseline AAA risk factors associated between men and women. After EVAR, women were 12% more likely to die than men, though no gender-based morality difference exists following OPEN repair. The differential treatment benefit of EVAR in women is concerning given the trend toward an endovascular-first treatment approach to AAA.