CLINICAL PORTRAIT OF PATIENTS WITH STAGE II HYPERTENSION AT DIFFERENT LEVELS OF TRANSFORMING GROWTH FACTOR β1 IN BLOOD PLASMA

Abstract

The aim of the study was to determine the clinical portrait of patients with stage II hypertension at different levels of transforming growth factor β1 (TGF- β1) in blood plasma. Echocardiography, Holter electrocardiographic monitoring, stress tests and/or coronary ventriculography were performed in 120 patients (mean age 57.3±0.9 years) to verify the diagnosis of stage II hypertension and concomitant chronic coronary heart disease (CCHD) and frequent ventricular extrasystole (VE). We allocated 4 groups of patients (30 persons in each): Group 1 – stage II hypertension without concomitant CCHD and frequent VE; Group 2 – stage II hypertension with concomitant frequent VE; Group 3 – stage II hypertension with concomitant CCHD; Group 4 – stage II hypertension with concomitant CCHD and frequent VE. Using an enzyme-linked immunosorbent assay with the “Human TGF-β1 (Transforming Growth Factor Beta 1) ELISA Kit” (Elabscience Biotechnology Inc., USA), the concentration of TGF-β1 in blood serum was determined according to the manufacturer’s instructions. Microsoft Excel (2019) and Statistica 12.0 (Statsoft, USA) were then used for statistical processing of the obtained results. By the method of variation statistics, the mean plasma concentration of TGF-β1 in the examined patients (n=120) was 9238.3±97.2 pg/mL. The median value was 222.0 pg/mL, and the interquartile range (25th and 75th percentiles) was 165.5 and 303.0 pg/mL, respectively. Taking the median into account, we distinguished groups of patients with a relatively low level (≤222 pg/mL) and a relatively high level (>222 pg/mL) of TGF-β1. It was determined that in 50% of the examined patients the plasma TGF-β1 concentration was 165.5– 303.0 pg/mL, in 25% it was below 165.5 pg/mL, and in the remaining 25% it was above 303.0 pg/mL. Moreover, an increase in its concentration was observed from Group 1 to Group 4. Clinical portraits of patients with stage II hypertension and different plasma TGF-β1 levels were determined using discriminant analysis (“Discriminant analysis”). The baseline parameter for the analysis was the mediator level expressed in points, where 1 point indicated a relatively low level and 2 points indicated a relatively high level of the hormone for the studied population of patients with stage II hypertension. Before performing discriminant analysis, a preliminary “filtering” of clinical and instrumental indicators (n=76) was carried out using Spearman rank correlation to determine their associations with the plasma hormone level. Indicators that showed a statistically significant (p<0.05) rank correlation with the plasma hormone concentration were included in the subsequent discriminant analysis. It was found that in patients with stage II hypertension and plasma TGF-β1 ≥222 pg/mL the following clinical portraits should be expected: 1) the presence of concomitant obesity; 2) the presence of concomitant obesity and angina pectoris without/with frequent VE. In this case, for functional class II angina the minimum number of VE episodes per day is 5000, whereas for functional class III it is 2500 VE episodes per day; 3) the presence of concomitant frequent VE >10,000 VE episodes per day.