Interplay Between Serum Osteocalcin and Insulin Sensitivity in Primary Hyperparathyroidism

Osteocalcin (OC) has been proposed as a regulator of insulin sensitivity in both humans and other animals. Primary hyperparathyroidism (PHPT) is characterized by high OC levels and insulin resistance. The aim of this study was to evaluate whether in PHPT the link between OC levels and blood markers of insulin resistance was maintained. In a consecutive series of 219 adult PHPT patients, serum OC as well as fasting insulin and glucose levels were measured. Insulin sensitivity was estimated by homeostatic model assessment (HOMA2-S%). The same parameters were evaluated in a subgroup of 45 patients after parathyroidectomy (PTX). PHPT patients were characterized by markedly high OC levels. After subdividing them according to glucose tolerance, it was found that OC was similar in subjects with normal glucose tolerance (NGT) and impaired glucose tolerance (IGT), while diabetic subjects had lower serum OC than those with NGT ( P