Carbohydrate and lipid metabolism disorders in women with primary hyperparathyroidism: results of cross-sectional study

Abstract

Background: Patients with primary hyperparathyroidism (PHPT) have increased mortality risk predominantly attributed to cardiovascular disease. Taking the risk factors for cardiovascular disease into account, such as overweight, atherogenic dyslipidaemia, carbohydrate metabolism disorders and insulin resistance (IR), investigation on the the study of the state of carbohydrate and lipid metabolism in patients with PHPT will help to shed light on the pathogenic mechanisms of the disease and, perhaps, to complement the algorithm for selecting treatment strategies for patients with PHPT.
 Aims: To study the prevalence of carbohydrate and lipid metabolism disorders among patients with PHPT and to identify the relationship between these two disorders with the indicators of mineral metabolism.
 Materials and methods: A case-control study of a total of age-matched 256 female patients, 220 patients with PHPT and 36 healthy individuals. The group patients with PHPT were sub-divided into two groups, symptomatic and mild form of PHPT. To verify the form of PHPT, ultrasound examinations of the parathyroid glands and kidneys, two-energy x-ray absorptiometry, biochemical studies (concentration of total and ionised calcium, serum phosphorus and the activity of alkaline phosphatase) and assessment of parathyroid hormone concentration were performed. The relationship between form of PHPT and body weight were evaluated retrospectively according to the survey. Among the 109 participants with PHPT (symptomatic PHPT: 82 patients; mild PHPT: 27 patients) and healthy individuals, the biochemical and hormonal parameters of fat (lipid spectrum of blood) and carbohydrate metabolism (content of immunoreactive insulin, HOMA index, presence of fasting glycemia disorder, glucose tolerance disorders and type 2 diabetes mellitus) were evaluated.
 Results: The symptomatic PHPT was associated with low body mass index (BMI) while the mild PHPT with high BMI. During an oral glucose tolerance test, the postprandial glycemia in symptomatic PHPT was significantly higher than that in mild PHPT (p = 0.036). The content of immunoreactive insulin in the symptomatic PHPT was not correlated with the concentration of parathyroid hormone, but positively correlated with the concentration of ionised calcium in the blood (r = 0.31; p = 0.006). Patients with PHPT showed a direct positive correlation between BMI and IR index (r = 0.67; p 0.001). It is shown that patients with PHPT have increased LDL content in the blood, and the actual blood lipid concentration is associated with the state of kidney function.
 Conclusions: The obtained data confirm the relationship between phosphoruscalcium metabolism disorders in PHPT and carbohydrate and lipid metabolism disorders. Prospective, controlled studies are warranted to better elucidate the causal relationships of mineral, carbohydrate and fat metabolism disorders in PHPT.