Elevated Serum Osteoprotegerin is Associated with Reduced Risks of Albuminuria and CKD Progression in Patients with Type 2 Diabetes

OBJECTIVE: To analyze the correlation between serum osteoprotegerin (OPG) level and chronic kidney disease (CKD) at different CKD stages in patients with type 2 diabetes. METHODS: All subjects were hospitalized patients with type 2 diabetes. Medical history collection, physical examinations, and blood and urine samples testing were performed. Stages of CKD (G1–5) were defined by eGFR, groups of persistent albuminuria (normal, microalbuminuria and massive albuminuria) were divided by UACR, and categories of CKD progression risks (low, moderate and high or very high risk) were recommended by the Kidney Disease: Improving Global Outcomes (KDIGO). Serum OPG level was determined by enzyme-linked immunosorbent assay in the central laboratory. RESULTS: Four hundred and eighty-four patients were included in the study. The average level of OPG of all subjects was 941.30 (547.53–1332.62) pg/mL. The levels of OPG decreased gradually with the aggravation of albuminuria (P = 0.007, P (for trend)=0.003) and CKD progression (P = 0.001, P (for trend)=0.001). No differences were found between OPG levels and stages of CKD (P = 0.31). After the adjustment, each 100 pg/mL increase in OPG levels could reduce the risk of massive albuminuria (OR 0.92, 95% CI 0.86–0.99, P = 0.02) and the high or very high risk of CKD progression (OR 0.94, 95% CI 0.89–0.99, P = 0.04) by multivariate logistic regression analysis. No correlations were found between OPG and stages of CKD. CONCLUSION: In patients with type 2 diabetes, elevated serum osteoprotegerin is associated with albuminuria and the risk of CKD progression, and may delay the progression of CKD.