THE CLINICAL PROFILE OF RUPTURE: A 19-YEAR CASE-CONTROL STUDY OF ABDOMINAL AORTIC ANEURYSMS

To identify factors associated with ruptured infrarenal abdominal aortic aneurysm (AAA) presentation and quantify ruptures below current sex-specific elective repair thresholds.

This retrospective case-control study compared patients presenting with ruptured infrarenal AAA with a contemporaneous comparison group undergoing elective infrarenal AAA repair. Multivariable logistic regression assessed associations with ruptured presentation. The primary model included maximum aneurysm diameter, age, female sex, and calendar year; the extended model additionally included hypertension, diabetes mellitus, and dyslipidemia. Discrimination was evaluated using optimism-corrected area under the curve (AUC).

Among 394 patients with infrarenal AAA, 194 presented with rupture and 200 underwent elective repair. Median diameter was 80.0 versus 53.0 mm (P < .001), and women comprised 10.9% versus 3.0% (P = .002), respectively. Diameter per 10-mm increase (odds ratio [OR], 2.19; 95% confidence interval [CI], 1.84-2.61) and female sex (OR, 4.72; 95% CI, 1.49-14.94) were independently associated with ruptured presentation. Optimism-corrected AUCs were 0.836 for diameter alone, 0.832 for the primary model (diameter, age, female sex, and calendar year), and 0.840 for the extended model (primary model plus hypertension, diabetes mellitus, and dyslipidemia). Sixteen of 160 ruptures (10.0%) occurred below sex-specific thresholds.

Diameter was the dominant factor associated with ruptured presentation, but female sex remained independently associated. These findings support diameter-based practice while highlighting the need for prospective, sex-aware, multiparametric risk assessment.