Abdominal Aortic Aneurysm in Women and Men: A Systematic Review of Sex-Specific Outcomes in the United Kingdom.

BACKGROUND: Abdominal aortic aneurysm (AAA) is less common in women than in men; however, when present, women appear to follow a more aggressive disease course, rupturing at smaller diameters and experiencing worse operative outcomes. The United Kingdom provides a unique environment in which to evaluate sex-specific outcomes, as national screening invitations are extended to men only and National Institute for Health and Care Excellence guidance applies a uniform 5.5 cm threshold for elective repair irrespective of sex.

METHODS: A systematic review was undertaken in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020. MEDLINE, EMBASE, and the Cochrane Library were searched to September 2025. Eligible studies reported sex-stratified outcomes for AAA in the United Kingdom. Gray literature was included through review of the National Vascular Registry, National Health Service AAA Screening Program reports, and National Institute for Health and Care Excellence guidance. Where sex-stratified numerators and denominators were available, crude odds ratios (ORs) were calculated and pooled using Der Simonian-Laird random-effects models. A separate adjusted-effects meta-analysis was performed using the generic inverse-variance method for studies reporting multivariable-adjusted ORs (adjORs).

RESULTS: Five peer-reviewed studies met inclusion, supported by national reports. Women had significantly higher perioperative mortality after elective endovascular repair (pooled OR 1.61, 95% confidence interval [CI] 1.31-1.97) and elective open repair (pooled OR 1.37, 95% CI 1.16-1.63). After ruptured repair, mortality was similar between sexes following endovascular aneurysm repair (EVAR) (pooled OR 1.11, 95% CI 0.89-1.39), but higher in women after open surgery (pooled OR 1.53, 95% CI 1.24-1.89), although with substantial heterogeneity. Adjusted-effects synthesis confirmed higher mortality for women after elective EVAR (summary adjOR ≈1.55, 95% CI 1.25-1.80) and open repair (adjOR 1.39, 95% CI 1.25-1.56). Women were less likely to undergo surgery following rupture, more likely to be readmitted after elective EVAR, had longer hospital stays, and higher long-term aortic-related mortality.

CONCLUSION: Women with AAA in the United Kingdom remain disadvantaged at every stage of care: they are less likely to be screened, rupture at smaller diameters, less often selected for repair, and when treated, face higher perioperative and long-term mortality. These disparities reflect a combination of anatomical and biomechanical differences, together with systemic factors. Current UK policy, based on male-only screening and a sex-neutral 5.5 cm threshold, does not reflect this reality. Sex-specific thresholds for repair, targeted female screening, and the development of devices optimized for female anatomy are needed to address inequity.