Malnutrition-Inflammation Liaison in Predicting AKI following OPCABG in Diabetics: Role of a Novel Monocyte/High-Density Lipoprotein × Albumin Ratio

Background Monocyte/high-density lipoprotein ratio (MHR) has been recently proposed as a parsimonious inflammatory marker. Akin to MHR, hypoalbuminemia (a malnutrition marker) has a considerable proinflammatory potential and confers an accentuated risk of postcardiac surgery complications, like acute kidney injury (AKI). The present study evaluated the AKI-predictive value of the preoperative monocyte/high-density lipoprotein × albumin ratio (MHAR) in diabetic patients undergoing off-pump coronary artery bypass grafting (OPCABG). Methods The retrospective study conducted at our tertiary cardiac care center included 687 diabetic OPCABG patients. Forty-eight hours postoperative data was evaluated for the occurrence of AKI, as defined by the Acute Kidney Injury Network criteria. The perioperative attributes of the AKI and non-AKI groups were compared to evaluate the predictors of AKI, by employing a regression analysis. Results A total of 109 patients (15.87%) developed AKI postoperatively. On univariate analysis: age, EuroSCORE II, preoperative congestive heart failure, systemic hypertension, serum albumin, MHR, MHAR, intraoperative packed red blood cell transfusion, postoperative low cardiac output syndrome, and vasoactive-inotropic score (VIS) predicted AKI. AKI subsequent to multivariate analysis, age (odds ratio [OR]: 1.029), EuroSCORE II (OR: 1.264), MHAR (OR: 1.403), and VIS (OR: 1.07) were the independent predictors (p-values: 0.020, < 0.001, 0.013, 0.002, respectively). The AKI predictive cutoffs of albumin, MHR, and MHAR were ≤ 2.95, ≥ 15.25, and ≥ 4.08 (area under the curve:sensitivity:specificity of 0.761:84.86%:89.62%; 0.754:93.12%:86.68%; 0.798:89.63%:88.34%, respectively). MHAR ≥ 4.08 was also associated with a higher incidence of postoperative atrial fibrillation and major adverse cardiac events. Conclusion Preoperative elevated MHAR independently predicts AKI following OPCABG in diabetics, implying a malnutrition-inflammation liaison at heart of the matter.