Fig. 1

Receiver operating characteristic (ROC) curves for differentiating CKD based on serum brain-derived neurotrophic factor (BDNF) levels at fasting (fasting BDNF), 30 min (BDNF at 30 min), and 120 min (BDNF at 120 min), and for calculating the area under the curve (AUC) of BDNF during the oral glucose tolerance test (OGTT)