Differences in Comorbidities Between Women and Men Treated with Elective Repair for Abdominal Aortic Aneurysms: A Systematic Review and Meta-Analysis.

OBJECTIVES: Elective abdominal aortic aneurysm (AAA) repair is performed to prevent rupture. For reasons as yet unknown, the 30-day mortality risk after elective AAA repair is higher in women than in men. We hypothesised that this higher risk might be related to differences in comorbidity. METHODS: Systematic review (PROSPERO CRD42019133314) according to PRISMA guidelines. A search in the EMBASE/MEDLINE/CENTRAL databases identified 1870 studies that included patients who underwent elective AAA repair (final search February 17th, 2021). Ultimately, 28 studies were included and all reported comorbidities were categorised into 17 comorbidity groups. Additionally, 15 groups of clearly defined comorbidities were used for sensitivity analysis. For both groups, meta-analyses of each comorbidity were performed to estimate the difference in pooled prevalence between women and men with a random effects model. RESULTS: When analysing data of all reported comorbidities (17 groups), smoking [risk difference (RD) 11%, 95% confidence interval (CI) 4-18], diabetes (RD 3%, 95% CI 2-4), ischaemic heart disease (RD 12%, 95% CI 8-16), arrhythmia (RD 3%, 95% CI 0.4-5), liver disease (RD 0.1%, 95% CI 0.01-0.2), and cancer (RD 3%, 95% CI 2-4)) were less prevalent in women, whereas, hypertension (RD 4%, 95% CI 3-6) and pulmonary disease (RD 4%, 95% CI 3-5) were more prevalent in women. At the time of surgery women were significantly older than men (74.9 years versus 72.4; mean difference 2.4 years (95% CI 2.1-2.7)). In the sensitivity analysis of 15 comorbidity groups, the same comorbidities remained significantly different between women and men, except smoking and arrhythmia. Women had a higher mortality risk than men (RD 1%, 95% CI 1-2). CONCLUSIONS: Although women undergoing elective AAA repair have fewer baseline comorbidities than men, their 30-day mortality risk is higher. In-depth studies on the cause of death in women after elective AAA repair are needed to explain this discrepancy in mortality.