Abstract Body (Do not enter title and authors here): Introduction: Controversy surrounding the appropriateness of abdominal aortic aneurysm (AAA) screening for women has resulted in conflicting professional guidelines. While it is known that women have lower incidence of AAA but higher disease-specific mortality, data is limited evaluating the impact of screening on postoperative outcomes among women.

Research Question: Is ultrasound screening for women associated with reduced sex disparities in postoperative outcomes after AAA repair?

Methods: We performed a retrospective cohort study of patients undergoing AAA repair using data from 100% claims of Fee-For-Service Medicare beneficiaries between 2015 and 2020. We identified patients who underwent ultrasound screening for AAA in the 6 months prior to surgery. To evaluate the impact of screening ultrasound on outcomes for women, we compared outcomes among female patients with and without prior ultrasound screening. To evaluate whether screening impacts sex disparities, we compared outcomes between unscreened men and women as well as between screened men and women. We used multivariable regression accounting for patient and facility characteristics.

Results: We identified 60,693 patients. Female patients were older (p<0.001) and had increased comorbidity burden (p<0.001). Among women, screening ultrasound was associated with lower rates of death or major complication (15.3 vs 16.0, aOR 0.94, 95% CI 0.88-0.99, p=0.03), unplanned surgery (p<0.001), and length of stay (p<0.001). Furthermore, lower complication rates among unscreened men relative to unscreened women (21.1 vs 21.9%, aOR 0.94, 95% CI 0.89-0.98, p=0.01) were no longer present in screened populations (20.2 vs 19.9%, p=0.8).

Conclusions: Screening ultrasound for AAA is associated with improved postoperative outcomes for women. Furthermore, sex disparities in AAA outcomes are mitigated in screened populations. This suggests that broader AAA screening criteria for women may improve outcomes and reduce sex disparities.