Ambulatory Blood Pressure Monitoring and Endothelial Dysfunction in Hypertensive Patients with Diabetes Mellitus Type 2

Abstract

Aim: Diabetic hypertensive patients have pronounced changes in ambulatory blood pressure profile and endothelial function. But the correlation between the parameters of ambulatory blood pressure monitoring (ABPM) and endothelial dysfunction in diabetic hypertensive patients have not been fully clarified. We studied ABP and endothelial function in a group of diabetic hypertensive patients. Methods: Patients with a glomerular filtration rate (GFR) of less than 30 mL/min per 1.73 m(2) were excluded. 120 patients were included into the research. Of these, the first (basic) group made up diabetic hypertensive patients in which there were 34 males and 26 females, the mean age was 56.1±1.3 years, the duration of arterial hypertension (AH) was 12.3±2.1 years and the duration of type 2 diabetes mellitus (DM2) was 4.4±0,7 years. The second (control) group made up 60 non-diabetic hypertensive patients in which there were 27 males and 33 females, the mean age was 55.2±1.2 year and duration of AH was 11.1±0.9 years. The patients in both groups were similar in age, duration of AH. Results:The analysis of the results of the 24-hour ABPM revealed that the number of patients with increased 24 hour systolic blood pressure (SBP) and diastolic blood pressure (DBP) variability was more among diabetic hypertensive patients than in non-diabetic hypertensive patients (76.7 % versus 21.1 and 70.0 % versus 22.5 %, respectively, p <0,05). There were not any significant changes in pulse rate, SBP and DBP. The amount of non-dipper and night-peaker patients was significantly higher in the basic group than in the control one (60.0 % versus 25.4 %, respectively, p <0,05). It was established that the number of patients with DBP daily value <10 was more significant in diabetic hypertensive patients versus non- diabetic hypertensive patients (33.3 % versus 18.2 %, respectively). We also determined nitric oxide metabolites concentration (nitrites and nitrates (NO)) and endothelin (ET-1) in serum and in 24 h-urine collection to assess endothelial function. So, the concentration of ET-1 in serum was significantly higher in diabetic hypertensive patients compared with non-diabetic hypertensive patients (2.49±0.01 pg/ml versus 1.5±0.07 pg/ml, respectively, p <0,05). NO metabolites concentration in serum and urine was significantly lower in the basic group than in the control group (12.7±1.5 uM versus 19,9±1,8 uM and 428.2±27.9 uM versus 792.1±39.4 uM, respectively, p <0,05). The direct association between SBP, DBP and ET-1 in urine were determined in diabetic hypertensive patients (r = 0.7, r = 0.99, respectively, p < 0.001). The correlation between daily index of SBP and ET-1 in urine (r = -0.58, p < 0.001), daily index of DBP and ET-1 in serum (r = -0.47, p < 0.001) were established in the basic group. Conclusion: The correlation between the parameters of ABPM and endothelial dysfunction in diabetic hypertensive patients were established in this study.