Objectives:
Patient selection and risk stratification for elective repair of abdominal aortic aneurysm (AAA), either by open surgical repair (OSR) or endovascular aneurysm repair (EVAR), remains challenging. CT-derived body composition analysis (CT-BC), and systemic inflammation-based scoring systems such as the systemic inflammatory grade (SIG), appear to offer prognostic value in patients with AAA undergoing EVAR. The relationship between CT-BC, systemic inflammation, and prognosis has been explored in patients with cancer, but data in non-cancer populations are lacking. The present study aimed to examine the relationship between CT-BC, SIG, and survival in patients undergoing elective intervention for AAA.

Methods:
611 consecutive patients undergoing elective intervention for AAA at three large tertiary referral centres were retrospectively recruited for inclusion into the study. CT-BC was performed and analysed using the CT-sarcopenia score (CT-SS). Subcutaneous and visceral fat indices (SFI, VFI) were also recorded. SIG was calculated from pre-operative blood tests. The outcomes of interest were overall and 5-year mortality.

Results:
Median (IQR) follow-up was 67.0 (32) months, and there were 194 (32%) deaths during the follow-up period. There were 122 (20%) OSR cases, 558 (91%) males, and a median (IQR) age of 73.0 (11.0) years. Age (HR 1.66, 95% CI 1.28 – 2.14, p <0.001), elevated CT-SS (HR 1.58, 95% CI 1.28 – 1.94, p <0.001), and elevated SIG (HR 1.29, 95% CI 1.07 – 1.55, p <0.01) were independently associated with increased hazard of mortality. Mean (95% CI) survival in the CT-SS 0 & SIG 0 sub-group was 92.6 (84.8 – 100.4) months, compared with 44.9 (30.6 – 59.2) months in the CT-SS 2 & SIG ≥ 2 sub-group (p <0.001). Patients with CT-SS 0 & SIG 0 had 90% (SE 4%) 5-year survival, compared with 34% (SE 9%) in patients with CT-SS 2 & SIG ≥ 2 (p <0.001).

Conclusions:
Combining measures of radiological sarcopenia and the SIR offers prognostic value in patients undergoing elective intervention for AAA and may contribute to future clinical risk predication strategies.