A simple preprocedural score for risk of contrast-induced acute kidney injury after percutaneous coronary intervention

Objective To develop a simple scoring system based on preprocedural clinical features that is capable of predicting contrast‐induced acute kidney injury (CI‐AKI) before percutaneous coronary intervention (PCI). Background CI‐AKI is associated with increased in‐hospital morbidity and mortality, prolonged hospitalization, and long‐term renal impairment. Although several scoring methods have been developed to determine risk of CI‐AKI, no simple scoring method based on PCI preprocedural clinical features yet exists for Chinese patients. Methods A total of 2,500 Chinese patients were randomly and retrospectively assigned in a 3:2 manner to create a training and validation dataset, respectively. CI‐AKI was defined as an increase of ≥25% or ≥0.5 mg/dL serum creatinine within 5 days after PCI. Preprocedural clinical variables showing independent correlation to CI‐AKI were used to derive the risk score from the training dataset and then subsequently tested in the validation dataset. The odds ratios from multivariate logistic regression were used to assign a weighted integer to age ≥70 years = 4, history of myocardial infarction = 5, diabetes mellitus = 4, hypotension = 6, left ventricular ejection fraction ≤45% = 4, anemia = 3, creatinine clearance rate