Metabolic features of young patients with primary hyperparathyroidism

Abstract

Background: The main components of mineral metabolism can influence non-classical target organs such as adipose tissue, pancreas, vascular wall. The «metabolic» effects of parathyroid hormone (PTH) and other participants of phosphorus-calcium metabolism in the hyperfunction of parathyroid glands remain unclear. The study of disorders of carbohydrate, fat and other types of metabolism in primary hyperparathyroidism (PHPT) will help to develop effective measures for prophylaxis and treatment of the patients in order to improve the quality and life span of the population.Aim: To study the main parameters of metabolism in young patients with an active stage of PHPT before surgical treatment.Materials and methods: A one-stage comparative study of young patients with PHPT and healthy volunteers matched by sex, age and body mass index (BMI) was carried out. The participants underwent a comprehensive biochemical and hormonal examination, a hyperinsulinemic euglycemic clamp and a bioimpedance analysis of the body composition.Results: 21 patients with PHPT and 18 healthy volunteers were included in the study. Patients with PHPT have higher level of serum triglycerides (p=0.003) without statistically differences of the main carbohydrate and purine parameters comparing with the control group. Visceral obesity were revealed in 42.9% of patients, including those with a normal BMI. Insulin resistance in the PHPT group was noted in 52.4% of cases, while the M-index was statistically lower than in the control subgroup (p=0.008), despite of the comparable body composition of the participants. The M-index showed a positive correlation with blood phosphorus level (p=0.010) only in the general group. Statistically positive correlations of PTH, albumin-corrected calcium and osteocalcin with triglyceride levels, calcium with fasting glycaemia, and PTH with uric acid levels were determined.Conclusion: PHPT is associated with insulin resistance in patients that is the main risk factor for the development of serious carbohydrate and fat disorders. The positive correlation of PTH and blood calcium levels with triglycerides, as well as the tendency to hypertriglyceridemia comparing with healthy volunteers, suggest the disease effect on the development of dyslipidemia.