Risk Stratification and Treatment Selection in Patients With Asymptomatic Abdominal Aortic Aneurysms

IMPORTANCE: Open surgical repair (OSR) should be prioritized for patients with asymptomatic abdominal aortic aneurysm (AAA) and long life expectancy, whereas endovascular repair (EVAR) is preferred for patients with suitable anatomy and life expectancy less than 2 to 3 years. However, life expectancy estimation and risk stratification are not well established.

OBJECTIVE: To evaluate risk-stratified survival differences between OSR and EVAR following elective AAA treatment.

DESIGN, SETTING, AND PARTICIPANTS: This cohort study used data from Danish national health registries. Patients older than 60 years undergoing elective AAA repair between 2004 and 2023 were categorized into 4 risk groups according to age, estimated glomerular filtration rate, and chronic obstructive pulmonary disease. Follow-up was until March 31, 2024.

EXPOSURE: OSR or EVAR for AAA.

MAIN OUTCOMES AND MEASURES: The primary outcome was overall survival. Secondary outcomes were incidence of AAA rupture and new cancer diagnosis. Comorbidities were balanced using inverse probability weighting. Kaplan-Meier estimators were generated for both treatments and the 4 risk score groups.

RESULTS: Of 6891 identified patients, 5757 (83.4%) were men. Women were older (median [IQR] age, 75.4 [70.9-79.3] vs 74.5 [70.5-78.5] years), more often had chronic obstructive pulmonary disease (156 women [13.6%] vs 512 men [8.9%]), and had lower estimated glomerular filtration rate (median [IQR], 68.4 [54.2-80.4] vs 70.4 [56.5-82.4] mL/min/1.73 m2) compared with men. The median follow-up was 8.28 years (95% CI, 8.10-8.50 years). OSR was associated with higher perioperative mortality in all risk groups. In low-risk patients, OSR was associated with a 10-month (95% CI, 2.2-18.3 months; P = .02) longer mean survival time restricted at 15 years compared with EVAR. In moderate-to-high-risk patients, OSR was associated with a 9-month (95% CI, 1.9-16.9 months; P = .008) shorter mean survival time restricted after 12.5 years compared with EVAR. No difference in mean survival time was seen in low-to-moderate-risk and high-risk patients at the study end. No differences in 10-year incidence of secondary AAA ruptures (OSR, 2.6% [95% CI, 1.9%-3.4%] vs EVAR, 2.2% [95% CI, 1.7%-2.7%]; P = .34) or solid malignant tumor (OSR, 18.6% [95% CI, 16.7%-20.5%] vs EVAR, 20.5% [95% CI, 18.9%-22.1%]; P = .35) were detected.

CONCLUSIONS AND RELEVANCE: In this cohort study of 6891 patients with AAA, OSR was associated with higher perioperative mortality in all risk groups, but with longer mean survival only in low-risk patients. Conversely, EVAR was associated with longer mean survival in moderate-to-high-risk patients. These findings highlight the potential benefits of risk stratification when planning AAA treatment.