Predictive value of the uric acid-to-albumin ratio for contrast-induced nephropathy after percutaneous coronary intervention and construction of a clinical prediction model in patients with coronary artery disease.

Background: Percutaneous coronary intervention (PCI) has become the cornerstone of coronary revascularization, and contrast-induced nephropathy (CIN) is one of the most frequent serious complications of PCI and is associated with prolonged hospitalization and higher mortality. We hypothesized that the uric acid-to-albumin ratio (UAR), a readily obtainable inflammatory-metabolic index, could enhance pre-procedural risk stratification for CIN. Methods: A consecutive cohort of 788 Chinese patients with coronary artery disease scheduled for elective PCI was enrolled. CIN was defined as an absolute serum creatinine rise ≥ 44.2 µmol/L or a ≥25% increase from baseline within 72 h of contrast exposure. Independent predictors were identified by multivariable logistic regression, and a base model was compared with a UAR-augmented model using the area under the ROC curve, net reclassification index, and integrated discrimination improvement. A nomogram was constructed, and a decision-curve analysis was performed. Results: CIN occurred in 76 patients (9.6%). UAR was the strongest single discriminator (AUC: 0.790) and remained independently associated with CIN (OR = 1.64; 95% CI: 1.42-1.90). Adding UAR to the base model increased the AUC from 0.850 to 0.921 ( Conclusion: UAR is a novel predictor of CIN after elective PCI. Its incorporation into a simple five-item nomogram significantly improves pre-procedural risk estimation and clinical decision-making. External validation is warranted before widespread implementation.