Insulin resistance adds to endothelial dysfunction in hypertensive patients and in normotensive offspring of subjects with essential hypertension

Žižek B, Poredos P (University Medical Centre, Ljubljana, Slovenia). Insulin resistance adds to endothelial dysfunction in hypertensive patients and in normotensive offspring of subjects with essential hypertension. J Intern Med 2001; 249: 189–197. Objectives. To evaluate whether endothelium-dependent (nitric oxide-mediated) dilation of the brachial artery (BA) is impaired in patients being treated for essential hypertension (EH), and whether this abnormality can be detected in normotensive offspring of subjects with EH (familial trait, FT); and to investigate the interrelationship between flow-mediated vasodilation (FMD) and hyperinsulinaemia/insulin resistance. Design. Cross-sectional study. Setting. Angiology department at a teaching hospital. Subjects. The study encompassed 172 subjects, of whom 46 were treated hypertonics aged 40–55 (49) years, and 44 age-matched, normotensive volunteers as controls. We also investigated 41 normotonics with FT aged 20–30 (25) years and 41 age-and sex-matched controls without FT. Main outcome measures. Using high-resolution ultrasound, BA diameters at rest, during reactive hyperaemia (endothelium-dependent dilation) and after sublingual glyceryl trinitrate (GTN) application (endothelium-independent dilation) were measured. Results. In hypertonics FMD was significantly lower than in controls [2.4 (2.9) vs. 7.4 (2.5)%; P