Plasma osteoprotegerin levels are associated with glycaemic status, systolic blood pressure, kidney function and cardiovascular morbidity in type 1 diabetic patients.
OBJECTIVE
The bone-related peptide osteoprotegerin (OPG) has recently been found in increased amounts in the vasculature in diabetes. It is produced by vascular smooth muscle and endothelial cells, and may be implicated in the development of vascular calcifications. OPG is present in the circulation, where increased amounts have been observed in patients with diabetes. In this study, we examined whether plasma OPG is associated with the glycaemic and vascular status of patients with type 1 diabetes.


METHODS
Two gender-, age- and duration-comparable groups of type 1 diabetic patients either with (n = 199) or without (n = 192) signs of diabetic nephropathy were studied. Plasma OPG was determined by an ELISA.


RESULTS
The plasma OPG concentration was significantly higher in patients with nephropathy than those without (3.11 (2.49-3.99) vs 2.57 (2.19-3.21) (median (interquartiles), ng/ml), P < 0.001). Plasma OPG correlated with haemoglobin A1c (HbA1c), systolic blood pressure and age in both groups and, in addition, with kidney function in the nephropathic group. These correlations remained significant in multivariate models. In addition, we found that plasma OPG concentrations were increased among patients with cardiovascular diseases (CVD), both in the normoalbuminuric and the nephropathic groups. The differences between nephropathic and normoalbuminuric, as well as subgroups with and without CVD, could largely be ascribed to changes in HbA1c, age, systolic blood pressure and creatinine.


CONCLUSIONS
OPG is associated with glycaemic control and CVD in patients with type 1 diabetes, compatible with the hypothesis that OPG is associated with the development of diabetic vascular complications.
Rasmussen
Lars Melholt
LM
Department of Clinical Biochemistry, University Hospital of Aarhus, Aarhus Amtssygehus, T. Hansengade 2, DK-8000 Aarhus C, Denmark. lmr@dadlnet.dk
Tarnow
Lise
L
Hansen
Troels Krarup
TK
Parving
Hans-Henrik
HH
Flyvbjerg
Allan
A
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000209:etiology*; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000150:complications; D003928:Diabetic Nephropathies / Q000097:blood*; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D008297:Male; D053244:Osteoprotegerin; D018160:Receptors, Cytoplasmic and Nuclear / Q000097:blood*; D018124:Receptors, Tumor Necrosis Factor / Q000097:blood*
D001786:Blood Glucose; D006442:Glycated Hemoglobin; D006023:Glycoproteins; D053244:Osteoprotegerin; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C506030:TNFRSF11B protein, human