Influence of insulin resistance and chronic low-intensity sistemic inflammation on the elasticity of the vascular wall in patients with arterial hypertension and non-alcoholic fatty liver disease
Authors: Derevyanchenko M , Streltsova A , Statsenko M 
Published: October 2021

Abstract

Introduction
Non-alcoholic fatty liver disease (NAFLD) is recognized as one of the leading causes of liver damage worldwide. Oxidative stress, mitochondrial abnormalities, C-reactive protein (CRP) are recognized as factors influencing the development of the pathological process in the liver. Insulin resistance, being the most important link in the pathogenesis of NAFLD, also affects a number of mechanisms of blood pressure regulation and contributes to an increase in the rigidity of the vascular wall.

Purpose
To assess the effect of insulin resistance and chronic systemic inflammation on the elasticity of the wall of the great arteries in patients with arterial hypertension (AH) and non-alcoholic fatty liver disease.

Material and methods
A cross-sectional comparative study was carried out. The main group included patients with AH and NAFLD (n=50), the control group included patients with isolated AH (n=50). To determine insulin resistance, the basal insulin concentration was measured and indices characterizing tissue sensitivity to insulin were used: the HOMA-IR index and the metabolic index (MI). HOMA-IR&gt;2 and MI≥7 index values indicated the presence of insulin resistance. The severity of chronic systemic inflammation was determined by the concentration of highly sensitive CRP and TNF-α in the blood serum. The wall stiffness of the great arteries was determined by the pulse wave velocity (PWV) index using the “Poly-Spectrum-8/E”.

Results
In the group with AH and NAFLD, compared with the group of isolated AH, the levels of insulin, HOMA-IR and MI were significantly higher (6.5 [4.1; 10.4] vs 3.6 [2.7; 4.6] (p=0.ehab724.2297), 1.5 [1.0; 2.3] vs 0.9 [0.7; 1.0]] (p=0.ehab724.2297), 8.1 [4.6; 13.6] vs 3.7 [2.2; 5.3] (p=0.0027), respectively). CRP and TNF-α were also significantly higher in patients with AH and NAFLD (13.0 [6.4; 15.0] vs 8.6 [1.5; 13.8] (p=0.0028), 9.2 [5.6; 12.4] vs 3.8 [2.4; 10.2] (p=0.ehab724.2297), respectively). Evaluation of the parameters of the stiffness of the main arteries revealed an increase in PWV muscle-type vessels (PWVm) and PWV elastic-type vessels (PWVe) in patients with AH and NAFLD compared with patients with isolated AH (11.5 [9.9; 12.9] m/s vs 8.9 [8.3; 11, 2] m/s (p=0.ehab724.2297) and 10.0 [8.6; 12.9] m/s vs 7.6 [7.1; 9.8] m/s (p=0,ehab724.2297), respectively). In addition, there are significantly more patients with PWVe≥10 m/s (50.0% vs 24.0%, p=0.0124). The performed multivariate regression analysis demonstrated that the most significant predictors of an increase in the PWV were MI and TNF-α level for muscle-type vessels, and TNF-α level for vessels of the elastic type.

Conclusions
In patients with AH and NAFLD, the indicators characterizing insulin resistance and chronic low-intensity systemic inflammation are significantly higher. Also, in comorbid patients, a significant increase in PWVm and PWVe was noted. MI and TNF-α are recognized as the most significant predictors of an increase in the pulse wave velocity in this category of patients.

Funding Acknowledgement
Type of funding sources: Public Institution(s). Main funding source(s): Grant of the Federal State Budgetary Educational Institution of Higher Education “The Volgograd State Medical University” of the Ministry of Health of the Russian Federation