ObjectiveTo construct a predictive model for acute kidney injury (AKI) after coronary artery bypass grafting (CABG) based on uromodulin (UMOD) and tumor necrosis factor receptor-associated factor 6 (TRAF6). MethodsPatients undergoing CABG treatment at Tianjin Chest Hospital from 2022 to 2024 were prospectively enrolled. Based on whether they developed AKI post-surgery, patients were divided into the an AKI group and a non-AKI group. Differences in UMOD, TRAF6, blood urea nitrogen (BUN), serum creatinine (SCr), β-N-acetylglucosaminidase (NAG), and SCr clearance rate at different time points were compared between the two groups. Predictive models for AKI after CABG were constructed at various time points, and the predictive efficacy of the models for AKI was analyzed. ResultsA total of 70 patients were included, with 22 in the AKI group [13 males and 9 females, aged 55-72 (67.91±4.91) years] and 48 in the non-AKI group [32 males and 16 females, aged 56-72 (68.07±4.67) years]. The UMOD levels in the AKI group were lower than those in the non-AKI group at various time points including before surgery (t=34.283, P<0.001), postoperative 2 h (t=29.590, P<0.001), 4 h (t=30.705, P<0.001), 8 h (t=26.620, P<0.001), 12 h (t=29.671, P<0.001), and 24 h (t=31.397, P<0.001). The TRAF6 levels in the AKI group were higher than those in the non-AKI group at all these time points (P<0.001). Multivariate analysis showed that higher levels of TRAF6, BUN, SCr, NAG, and lower levels of UMOD and SCr clearance rate were risk factors for AKI after CABG (P<0.05). The receiver operating characteristic curve analysis showed that the area under the curve of the predictive model at postoperative 12 h was significantly higher than that of the remaining models. The risk of AKI after CABG was: log (Y)=12.333−1.582×UMOD+1.270×TRAF6+1.356×BUN+1.356×SCr+1.355×NAG−1.254×SCr clearance rate. ConclusionIn the occurrence process of AKI after CABG, TRAF6 exacerbates renal injury by activating inflammatory signals and promoting cell apoptosis, while UMOD alleviates renal injury by regulating renal tubular function and protecting renal tubular epithelial cells. Through the simulation analysis of the two biomarkers combined with renal injury indicators at postoperative 12 h, the occurrence of AKI after CABG can be effectively predicted.