The areas under the ROC curve (AUCs) of the preoperative and post-CPB syndecan-1 concentrations to predict severe AKI were 0.714 (95% CI, 0.575–0.853; p = 0.009) and 0.653 (95% CI, 0.497–0.809; p = 0.063), respectively (Figure 2). Here, SDC1 is linked to acute kidney injury.