Title : Asymmetrical dimethylarginine in uncontrolled arterial hypertension
We conducted a comparative analysis of ADMA plasma concentration in two groups of patients diagnosed with arterial hypertension (AH). Group I - patients with uncontrolled course of disease and group II- patients with controlled course of hypertension. We studied the correlation analysis of ADMA level with laboratory and instrumental data in both groups.
Methods: We included 109 patients in our study: group I – 73 patients, group II – 36 patients. The following procedures were performed: measurement of blood biochemical parameters, including lipid profile, concentration of creatinine and glomerular filtration rate (GFR) in the blood serum and a carotid doppler ultrasonography (CDU). The criteria for including patients in group II was the constant use of correctly selected therapy for hypertension (according to international standards), the 24-hour BP monitoring indexes within the reference values and also absence of the hypertensive crises during the last 3 years.
Results: The concentration of ADMA in patients with uncontrolled hypertension was 0.69 [0.62-0.81] μmol/L and was significantly higher than in patients in the group II, where the mean ADMA concentration was 0.63 [0.59 -0.70] μmol / L (p <0.05). In patients of group I, there was a positive correlation between the ADMA level and the creatinine level (r = 0.615, p <0.05), and a negative association between the ADMA level and the renal filtration function which was assessed by GFR (r = -0.444, p <0.05). In the group II ADMA level was not correlated to renal function (p> 0.05), but a positive association of moderate strength were revealed with serum glucose and triglyceride concentrations. Correlation coefficients for these pairs of indicators were r = 0.416 and r = 0.409, respectively (p <0.05). Other parameters of the lipid profile in the group II, as in group I, were not associated with the level of ADMA (p> 0.05). When analyzing intergroup differences of the results of CDU, no significant differences were found (p>0.05). However, a correlation analysis revealed a positive relationship between the level of the brachiocephalic arteries stenosis and the level of ADMA in patients of group I (r = 0,495, p<0.05). Also, we found a positive correlation between the level of the brachiocephalic arteries stenosis and some laboratory data: creatinine and triglycerides concentrations in group I; r = 0.423 and r =0.433 respectively (p <0.05). According to the results of our analysis, in patients of group I, there was a negative association between the Intima-Medial Thickness and the renal filtration function which was assessed by GFR (r = -0.4, p <0.05), while in patients with controlled course of hypertension, no correlations were found.
Conclusions: Significant increase in the level of ADMA in patients of both groups was found in comparison with the physiological norm (p <0.05), and it was significantly higher in patients with uncontrolled course of hypertension in comparison with the ones in group II. Our study showed significant positive correlations between indicators of target organ damage and ADMA level and it was significantly higher in patients with uncontrolled course of hypertension.
Audience take away:
- ? number of researchers consider asymmetric dimethylarginine as one of the markers of endothelial dysfunction in arterial hypertension. Asymmetric dimethylarginine (ADMA) is an endogenous competitive inhibitor of endothelial NO-synthase (eNOS), which is synthesized as a result of the hydrolysis of proteins rich in methylated arginine residues. The physiological concentration of ADMA in plasma is about 0.46 - / + 0.19 μmol / l.
- Significant increase in the level of ADMA in patients with arterial hypertension was found in comparison with the physiological norm (p <0.05), and it was significantly higher in patients with uncontrolled course of hypertension in comparison with the ones in another group.
- The presence of significant correlation of ADMA level in the blood plasma with a number of clinical, instrumental and laboratory data of patients with arterial hypertension indicates the potential use of this substance as a marker of the severity of pathological changes in microcirculation and prognosis of the disease.