Inflammatory Prognostic Index May Predict the Development of Contrast-Induced Nephropathy in Patients with ST-Segment Elevation Myocardial Infarction

Contrast-induced nephropathy (CIN) remains a frequent and clinically relevant complication in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCI). This study evaluated the predictive performance of inflammation-based indices for CIN development, with a focus on the inflammatory prognostic index (IPI). STEMI patients (n = 563) were retrospectively analyzed. CIN developed in 85 patients (15.1%). Admission IPI values were significantly higher in patients who developed CIN compared with those without CIN (10.9 [7.6-16.2] vs 4.8 [3.1-7.9], P < .001). In multivariate logistic regression analysis, IPI remained independently associated with CIN (odds ratio [OR] 1.31, 95% confidence interval [CI] 1.06-1.61, P = .013), together with advanced age, higher blood urea nitrogen levels, reduced left ventricular ejection fraction, history of stroke, and the occurrence of no-reflow. Receiver operating characteristic analysis demonstrated superior discriminative performance for IPI (area under the curve [AUC] 0.826, 95% CI 0.783-0.869) compared with neutrophil-to-lymphocyte ratio (NLR; AUC 0.691), C-reactive protein-to-albumin ratio (CAR; AUC 0.712), and systemic immune inflammation index (SII; AUC 0.704). An admission IPI cutoff value of 8.35 predicted CIN with 82.4% sensitivity and 65.9% specificity. IPI demonstrates superior discriminative performance compared with CAR, NLR, and SII for predicting CIN in STEMI patients undergoing pPCI.