Abdominal Arterial Calcification Score-Association With Patient Survival Post Kidney Transplant

Abstract

Background: Abdominal arterial calcification (AAC) is a common comorbidity in patients with end-stage kidney disease (ESKD) and a predictor of cardiovascular events post-kidney transplant. However, prior studies lacked a standardized approach to evaluate AAC and its impact on post-transplant outcomes. This study aimed to correlate AAC score values with post-kidney transplant outcomes using a modified scoring system traditionally applied to coronary artery calcification. Methods: This retrospective study included 14 339 adult patients listed for kidney transplant between 2002 and 2023 at three transplant centers. Among them, 3683 patients met the criteria of undergoing a kidney transplant and an abdominal computed tomography (CT) scan pre-transplant. We modified the coronary calcium score software by adjusting intake data points to quantify calcification in the abdominal aorta, common iliac, external iliac, and internal iliac arteries. Outcomes focused on post-transplant mortality. Results: In 3683 kidney transplant recipients, higher AAC scores were significantly associated with increased mortality. Each 1000-unit increase in AAC score elevated hazard ratios (HRs) across arterial regions, including 1.116 for the aorta and 1.389 for the internal iliac (all p < 0.001). Adjusted analyses confirmed AAC as an independent risk factor for mortality. Kaplan-Meier curves demonstrated lower survival with increasing AAC quartiles. Conclusions: AAC, measured by a standardized score, is a significant mortality risk factor in kidney transplant recipients. Integrating AAC scores into pre-transplant evaluations could enhance risk stratification and improve outcomes. Prospective studies are needed to validate these findings and explore interventions to reduce AAC and improve survival.