Risk Score for Predicting Acute Kidney Injury from Contrast-Enhanced Computed Tomography (Pre-Computed Tomography Acute Kidney Injury Score)

Abstract

Key Points There is a well-established score for predicting contrast-associated AKI (CA-AKI) after coronary angiography, but there remains a paucity of data regarding its prediction after contrast-enhanced computed tomography (CT). CA-AKI after contrast-enhanced CT risk factors are male sex, admission setting, hemoglobin <10 g/dl, and eGFR. Pre-CT AKI score, using these factors, predicts CA-AKI risk with an area under the receiver operating characteristic curve of 0.715 and 0.706 for external validation. Background The lack of a recognized risk evaluation for contrast-associated AKI (CA-AKI) after contrast-enhanced computed tomography (CECT) makes it challenging to counsel patients before the procedure. This study aims to identify the incidence of CA-AKI after CECT, assess the associated risk factors, and develop and validate a predictive score. Methods All adult patients who underwent CECT in 2018–2022 were included in the training cohort, whereas those in 2023 formed the external validation cohort. Exclusions applied to patients with CKD stage 5, recent dialysis, or incomplete data. Multiple logistic regression was used to identify risk factors. The area under the receiver operating characteristic curve was used to evaluate both internal and external validation. Results From 21,878 enrolled patients, 6042 and 2463 met the inclusion criteria for the training and validation cohorts with a mean eGFR of 86.0 (26.4) and 81.4 (27.6) ml/min per 1.73 m 2 , respectively. In the training cohort, 492 patients (8.1%) developed CA-AKI, and 49 (0.8%) required dialysis. Independent risk factors of CA-AKI included male sex, clinical setting, hemoglobin levels of <10 g/dl, and baseline eGFR <90 ml/min per 1.73 m 2 . The model, using a weighted integer score derived from these factors, exhibited an area under the receiver operating characteristic curve of 0.715 (95% confidence interval, 0.692 to 0.743) in the training cohort and 0.706 (95% confidence interval, 0.663 to 0.748) in the validation cohort. Conclusions CECT can lead to CA-AKI in specific populations. The pre-computed tomography AKI risk score for CA-AKI after CECT demonstrated good discriminative power and can be easily applied in clinical practice.