Association between plasma osteoprotegerin concentrations and urinary albumin excretion in Type 2 diabetes.

AIMS: Osteoprotegerin (OPG) is a recently identified inhibitor of bone resorption. Recent studies indicate that OPG is also associated with endothelial dysfunction in Type 2 diabetes. The aim was to investigate the relationship between plasma OPG levels and urinary albumin excretion (UAE) in Type 2 diabetic patients. METHODS: This study included 154 newly diagnosed Type 2 diabetic patients and 46 healthy subjects. Plasma OPG and 24-h UAE were measured. High-resolution ultrasound was used to measure flow-mediated (endothelium-dependent arterial) dilation (FMD). RESULTS: Compared with the normoalbuminuric subgroup, OPG levels in the microalbuminuric subgroup were significantly higher, and OPG levels in macroalbuminuria subgroup were significantly higher than those in the normoalbuminuria and albuminuria subgroups. Multiple regression analysis showed that only FMD (r = -0.26), C-reactive protein (r = 0.23), fasting blood glucose (r = 0.25), 2-h blood glucose (r = 0.21), HbA(1c) (r = 0.28), UAE (r = 0.27) and retinopathy (r = 0.27) were significant factors associated with OPG. Pearson's correlation analyses showed a positive correlation between OPG and logUAE (r = 0.440) and negative correlations between OPG and FMD (r = -0.284), and between FMD and logUAE (r = -0.602). CONCLUSIONS: Plasma OPG levels are significantly associated with UAE in Type 2 diabetic patients.