The effect of renal dysfunction on circulating sclerostin level in patients with type 2 diabetes

Objective. Sclerostin is a Wnt inhibitor produced specifically by osteocytes. However, it is not currently clear whether renal dysfunction has an effect on circulating sclerostin level in patients with type 2 diabetes. The aim of the study was to evaluate this relationship. Design and Patients. We conducted a cross-sectional observational study of 302 type 2 diabetic patients with or without chronic kidney disease. Serum sclerostin level was analyzed by ELISA, and renal function was assessed by estimated glomerular filtration rate (eGFR) using chronic kidney disease epidemiology collaboration (CKD-EPI) equation. Results. There was a strong correlation between sclerostin level with renal function presented as serum creatinine (r = 0.745, P < 0.001) and eGFR (r = -0.590, P < 0.001). Serum sclerostin level was significantly higher in patients with CKD-G3 stage than those with CKD-G1/2 stages after adjusting for age, sex, and BMI (P = 0.011). Patients with CKD-G4/5 stages had dramatically increased level of circulating sclerostin. Multiple regression analyses found that age, sex, and eGFR were independent determining factors for circulating sclerostin level. Conclusion. Our data showed that serum sclerostin levels start to increase in diabetic patients with CKD-G3 stage. Further studies are needed to establish the potential role of elevated sclerostin in diabetic patients with CKD.