Assessment of endothelial function among patients with type 2 diabetes mellitus

Background: Endothelial dysfunction is an initial key step in the pathogenesis of atherosclerosis. Many tests developed to measure endothelial function, most of which are either invasive or semi-invasive. The unique nature of brachial artery reactivity test of being a noninvasive, quantitative, and repeatable procedure is gaining increasing interest as an index in assessing endothelial cell function. Aim of Study: The aim is to study the assessment of endothelial function among a group of patients with type 2 diabetes mellitus (DM), using brachial artery reactivity test. Patients and Methods: In a case control study enrolling 35 patients with type 2 DM matched against a similar number of nondiabetic participants of related genders and age groups to trace the brachial artery diameter both at rest and in response to reactive hyperemia using a commercially available U/S machine equipped with a high-resolution linear probe (7.5 MHz) following an already defined U/S protocol. Results: The diabetic participants revealed a statistically significant attenuation in brachial artery dilatation in response reactive hyperemia when compared with nondiabetic group (mean ± standard deviation) (4.63 ± 0.4 mm vs. 5.61 ± 0.47 mm). Comparing the two groups, a statistically significant impairment of the brachial artery dilatation is traced in relation to the atherosclerotic risk factors both in isolation and in clusters. Moreover, strict glycemic control (HbA1c ≤6%) significantly altered the response to vasodilatation (0.74 ± 0.17 mm vs. 0.43 ± 0.14 mm, P = 0.0001). Age, gender difference, and duration of diabetes did not significantly alter the results. Conclusions: Endothelial dysfunction is not uncommon among patients with type 2 DM. Brachial artery reactivity test is a well-accepted, noninvasive, repeatable, and a quantitatively reproducible index to trace endothelial function.