The purpose of the study was to evaluate the effect of levothyroxine supplementation on vascular endothelium status and markers of chronic systemic inflammation in patients with combined course of arterial hypertension, type 2 diabetes mellitus, and subclinical hypothyroidism. Material and methods. The study included 32 patients (mean age 59.3±3.5 years) with arterial hypertension stage II in combination with type 2 diabetes mellitus and subclinical hypothyroidism. The inclusion criterion was the presence of a TSH level of more than 6.0 mIU / L in the screening period. The control group consisted of 30 representatives by age and gender, without cardiovascular disease and endocrinopathies. Levothyroxine was administered in individually selected doses of 12.5 to 50 mg/day with gradual dose titration (21 day titration step) until euthyroidism was reached. The period of observation was 1 year, 28 (87.5 %) patients completed the study. Plasma levels of vasculoendothelial growth factor (VEGF–A), C–reactive protein, tumor necrosis factor–α (TNF–α) were checked by ELISA. The number of desquamating circulating endothelial cells in the blood was determined by the method of Hladovec J. in the modification of Rajec J. et al. using phase contrast microscopy. Statistical processing of data was performed with the computer program SPSS 21.0. Results and discussion. A comparative analysis revealed signs of chronic systemic inflammation, endothelial dysfunction on the background of decreased thyroid function in patients with arterial hypertension, type 2 diabetes mellitus and subclinical hypothyroidism compared with the control group. Correlation analysis revealed a positive correlation between VEGF–A and TSH levels (r=0.421, p=0.001). Improvement of the thyroid function on the background of treatment with levothyroxine was accompanied by a significant decrease in the level of VEGF–A (before treatment 585,67±35,08 pg / ml, after treatment – 462,58±32,18 pg / ml, p<0,001, respectively), not a significant decrease in the desquamating circulating endothelial cells count (before treatment it was 10.28±0.61 (cell./100 μl), after treatment it was 10.16±0.59 (cell./100 μl), p = 0.083, respectively), a slight but significant decrease of C–reactive protein (p<0.001) and TNF–α (p <0.001). Post–treatment correlation analysis revealed a positive relationship between free T3 and VEGF–A levels (r = 0.481, p = 0.015), and a negative relationship between desquamating circulating endothelial cells and free T4 levels (r = 0.457, p = 0.022). Conclusion. The use of levothyroxine in the complex treatment of patients with combined course of arterial hypertension, type 2 diabetes mellitus and subclinical hypothyroidism was accompanied by an improvement in the functional state of the endothelium, which together with decreased markers of chronic systemic inflammation improved the prognosis for this cohort of patients.
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