DO GENES AFFECT METABOLIC AND HORMONAL PARAMETERS IN PATIENTS WITH ESSENTIAL ARTERIAL HYPERTENSION?

Abstract

Objective: The aim of the study was to analyze metabolic and hormonal parameters changes in patients with essential arterial hypertension (EAH) depending on the vitamin D receptor gene (VDR, rs2228570) polymorphism. Design and method: The study involved 100 patients suffering from EAH with target-organ damaging, moderate, high or very high cardiovascular risk. Among them were 79.0% (79) women and 21.0% (21) men, an average age was 59.87±8.02 yo. The control group involved 60 practically healthy persons, matched by age and gender distribution. All enrolled/screened patients signed the Informed Consent to participate in the research. The VDR gene (rs2228570) polymorphism was studied by a real-time polymerase chain reaction (RT-PCR) method. The intact parathyroid hormone (intact PTH) and vitamin 25 (OH) D levels in blood serum were determined by chemiluminescence immunoassay (MAGLUMI). Results: The decreased level of vitamin 25 (OH) D (<30 ng/ml) was found more often in the A-allele carriers of the VDR gene (rs2228570), than in GG-genotype carriers: in the control group - by 36.84% (x2 = 10.32; p = 0.001), in study group - by 42.42% (x2 = 39.27; p<0.001). Hypocalcemia according to the level of ionized blood calcium (Ca2+ <1.12 mmol/l) was registered only in G-allele carriers, both among practically healthy and hypertensive patients. In the control group, GG-genotype carriers had a lower ionized Ca2+ blood level with a compensatory higher concentration of the intact PTH in comparison with A-allele carriers - by 3.42%, 25.19% and 16.03% (p<0.05), respectively. Secondary hyperparathyroidism due to a compensatory increasing of the intact PTH (>65 pg/ml) was found more often in the G-allele carriers of the VDR gene (rs2228570) than in AA-genotype carriers: in control group - by 55.55% (x2 = 11.11; p<0.001), and in the group of patients with EAH - by 62.5% (x2 = 12.5; p<0.001). Conclusions: The GG-genotype of the VDR gene (rs2228570) increases the risk of hypocalcemia by more than 6 times [OR = 6.25; 95% CI: 1.05-37.37; p = 0.046], with the lowest probability in carriers of the A-allele [OR = 0.16; 95% CI: 0.03-0.96].