Preoperative serum ST2 level predicts acute kidney injury after adult cardiac surgery

Objective: The purpose of this study was to evaluate the relationship between preoperative levels of serum soluble ST2 (ST2) and acute kidney injury (AKI) after cardiac surgery. Previous research has shown that biomarkers facilitate the prediction of AKI and other complications after cardiac surgery. Methods: Preoperative ST2 proteins were measured in 1498 patients undergoing isolated coronary artery bypass graft surgery at 8 hospitals participating in the Northern New England Biomarker Study from 2004 to 2007. AKI severity was defined using the Acute Kidney Injury Network (AKIN) definition. Preoperative ST2 levels were measured using multiplex assays. Ordered logistic regression was used to examine the relationship between ST2 levels and levels of AKI severity. Results: Participants in this study showed a significant association between elevated preoperative ST2 levels and acute kidney risk. Before adjustment, the odds of patients developing AKIN stage 2 or 3, compared with AKIN stage 1, are 2.43 times higher (95% confidence interval, 1.86-3.16; P <.001) for patients in the highest tercile of preoperative ST2. After adjustment, patients in the highest tercile of preoperative ST2 had significantly greater odds of developing AKIN stage 2 or 3 AKI (odds ratio, 1.99; 95% confidence interval, 1.50-2.65; P <.001) compared with patients with AKIN stage 1. Conclusions: Preoperative ST2 levels are associated with postoperative AKI risk and can be used to identify patients at higher risk of developing AKI after cardiac surgery.