Introduction:
Osteoprotegerin has been shown to play a role in vascular calcification, atherosclerosis and the pathogenesis of cardiovascular diseases. We aimed to evaluate whether excess fat mass affects serum osteoprotegerin concentrations and to evaluate its associations with chosen cardiometabolic risk factors in overweight and obese children.

Material and methods:
We enrolled 105 children ranging from 7.0 to 17.8 years of age. Among them 70 individuals were overweight and obese, and 35 were healthy with normal physical parameters. In all patients, anthropometric measurements and laboratory tests were performed. Atherogenic and insulin resistance indices were calculated.

Results:
We did not find any differences in serum osteoprotegerin concentrations between overweight and obese children and their lean peers. In all studied patients, together with elevated quartiles of osteoprotegerin concentration, insulin resistance status decreased, and low-density lipoprotein cholesterol concentration increased. In the group of overweight and obese children osteoprotegerin was associated with low-density lipoprotein cholesterol, total cholesterol, and non high-density lipoprotein cholesterol. In the multiple linear regression analysis osteoprotegerin correlated only with low-density lipoprotein cholesterol (β = 0.140, p = 0.005).

Conclusions:
Insulin resistance and lipid profile seem to influence circulating osteoprotegerin levels, but most likely needs more time to change its concentration in overweight and obese patients. The association of osteoprotegerin with low-density lipoprotein cholesterol may suggest its link with atherogenesis.