Gender differences in abdominal aortic aneurysms in Germany using health insurance claims data

Background: Endovascular aortic repair (EVAR) has emerged as standard of care for abdominal aortic aneurysm (AAA). Real-world evidence is limited to compare this technology to open repair (OAR). Major gaps exist related to short-term and long-term outcomes, particularly in respect of gender differences.

Materials and methods: Health insurance claims data from Germany's third largest insurance provider, DAK-Gesundheit, was used to investigate invasive in-hospital treatment of intact (iAAA) and ruptured AAA (rAAA). Patients operated between October 2008 and April 2015 were included in the study.

Results: A total of 5,509 patients (4,966 iAAA and 543 rAAA) underwent EVAR or OAR with a median follow-up of 2.44 years. Baseline demographics, comorbidities, and clinical characteristics of DAK-G patients were assessed. In total, 84.6 % of the iAAA and 79.9 % of the rAAA were male. Concerning iAAA repair, the median age (74 vs. 73 years, p < .001) compared to men was higher in females, but their EVAR-rate (66.8 % vs. 71.1 %, p = .018) was lower. Besides higher age of female patients (80 vs. 75 years, p < .001), no further statistically significant differences were seen following rAAA repair. In-hospital mortality was slightly lower in males compared to females following iAAA (2.3 % vs. 3.1 %, p = .159) and rAAA (37.3 % vs. 43.1 %, p = .273) repair. Concerning iAAA repair, a higher rate of female patients was transferred to another hospital (3.7 % vs. 2.0 %, p = 0.008) or discharged to rehabilitation (6.0 % vs. 2.7 %, p < .001) compared to male patients.

Conclusions: In this large German claims data cohort, women are generally older and more often transferred to another hospital or discharged to rehab following iAAA repair. Nonetheless, no significantly increased risk of in-hospital or late death appeared for women in multivariate analyses. Further studies are necessary to evaluate the impact of recent gender-specific treatment strategies on overall outcome under real-world settings.