A simple risk score for prediction of contrast-induced nephropathy after percutaneous coronary intervention: Development and initial validation

Objectives We sought to develop a simple risk score of contrast-induced nephropathy (CIN) after percutaneous coronary intervention (PCI). Background Although several risk factors for CIN have been identified, the cumulative risk rendered by their combination is unknown. Methods A total of 8,357 patients were randomly assigned to a development and a validation dataset. The baseline clinical and procedural characteristics of the 5,571 patients in the development dataset were considered as candidate univariate predictors of CIN (increase ≥25% and/or ≥0.5 mg/dl in serum creatinine at 48 h after PCI vs. baseline). Multivariate logistic regression was then used to identify independent predictors of CIN with a p value 75 years, anemia, and volume of contrast) were assigned a weighted integer; the sum of the integers was a total risk score for each patient. Results The overall occurrence of CIN in the development set was 13.1% (range 7.5% to 57.3% for a low [≤5] and high [≥16] risk score, respectively); the rate of CIN increased exponentially with increasing risk score (Cochran Armitage chi-square, p c statistic = 0.67); the increasing risk score was again strongly associated with CIN (range 8.4% to 55.9% for a low and high risk score, respectively). Conclusions The risk of CIN after PCI can be simply assessed using readily available information. This risk score can be used for both clinical and investigational purposes.