A Spearman correlation analysis showed that serum sclerostin was negatively correlated with eGFR (r =  − 0.214, p = 0.011), and a higher level was observed in patients with stage 5 as compared to stage 3 CKD (42.53 vs 52.64 ng/ml, median, p = 0.048), although the levels were comparable between stages 3 and 4 (42.53 vs 44.11 ng/ml, p = 0.741) and between stages 4 and 5 (44.11 vs 52.64 ng/ml, p = 0.115) (Fig. 1). This evidence concerns the gene SOST and chronic kidney disease.