Validation of Renal Risk Score Models for Coronary Artery Bypass Surgery in Diabetic Patients

Abstract

Coronary artery bypass grafting is applicable with very low mortality and morbidity rates around the world. However, exposure to even one of the risk factors increases mortality and morbidity significantly. There are three acute kidney injury definitions, and classification methods are applicable (Kidney Disease: Improving Global Outcomes (KDIGO); Risk, Injury, Failure, Loss of kidney function and End-stage kidney disease (RIFLE);" (for accuracy) and Acute Kidney Injury Network (AKIN)), for understanding and grading of renal impairment. With these definitions, it became possible to take measures at an early stage and start the management process. Methods for assessing renal impairment after coronary artery bypass grafting (CABG) specifically in patients with diabetes mellitus require further investigation. We compared these three acute kidney injury definitions for prediction of outcomes in diabetic patients undergoing coronary artery bypass grafting procedure. Between January 2010 and December 2013, a total of 617 consecutive patients with diabetes mellitus undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass in our institution were included in the study. We considered 617 CABG operations on diabetes mellitus patients for this study from January 2010 to December 2013. The three scores provided good discriminative capacity in the global patient sample, with the area under the ROC curve (AUC) being higher, RIFLE (0.803, 95% CI: 0.724-0.882). The goodness of fit was good for all scales. Especially in on-pump CABG patients with diabetes mellitus, we can use AKIN, RIFLE, and KDIGO scoring systems to predict early diagnosis for acute kidney injury (AKI). In our analysis, the KDIGO criterion was superior to AKIN and RIFLE with regard its prognostic power.