Relationship Between Inflammation and Endothelial Dysfunction in Essential Hypertension

Abstract

Background: A proposed pathogenic link between inflammation and hypertension is possibly through endothelial dysfunction. Objective: To study the relationship between inflammation and endothelial dysfunction in essential hypertension Methods: In a cross-sectional prospective study, 102 patients with essential hypertension underwent endothelial function evaluation at rest and after reactive hyperaemia by high-resolution B-mode ultrasound images in right upper arm after a written, informed consent. Glucose, lipid profile, creatinine, hsCRP (Diagnostics Biochem Canada Inc.), IL-6 (BD OptEIA™) and TNF- α (BD OptEIA™) were estimated in a 12 hours overnight fasting blood sample. Results: 102 patients (mean age 45 ± 8years, duration of hypertension 3.89 ± 0.43 years, and antihypertensive treatment in 91% and statins in 39.2%) were studied. The mean flow mediated vasodilatation (FMD) of the brachial artery was 12.2 ± 8.0%. 39 (38.2%) of patients had an abnormal FMD (a change of less than 10% in the diameter of the vessel wall). No correlation was found between FMD and duration of hypertension, systolic or diastolic blood pressure, body mass index, waist circumference or lipid profile using Spearman's test of correlation. hsCRP (75 patients), TNF-α levels (75 patients) and IL-6 levels (64 patients) were 69.5 ± 67.4 mg/L,125 ± 252pg/ml and 527 ± 1253pg/ml respectively. No correlation was found between any of the inflammatory markers and brachial FMD. Conclusions: A significant inflammation was observed in well controlled hypertensive patients. However there was no correlation between endothelial dysfunction and the degree of inflammation. Absence of target organ damage, younger age, shorter duration of hypertension and treatment could be the factors responsible for the same.