Evaluation of endothelial function in hypertensive elderly patients by high-resolution ultrasonography

Background: Multiple investigations, both in experimental models and in mid dle-aged patients with essential hypertension, demonstrate impaired endothe lium-dependent vasodilatation. Hypothesis: We attempted to determine whether hypertension still exerts add itional negative effect on endothelial function of large arteries in hypert ensive elderly patients who may already be affected by endothelial dysfunct ion due to aging. Methods: We compared 13 elderly patients with hyper tension [69 +/- 9 years , (mean +/- standard deviation)] with 13 matched healthy elderly subjects ( 72 +/- 6 years) as controls. Using high-resolution vascular ultrasound, we measured brachial artery responses to reactive hyperemia (with increased fl ow causing endothelium-dependent dilatation) and sublingual nitroglycerin ( causing endothelium-independent dilatation). Results: Flow-mediated dilatation correlated inversely with age (r = -0.60, p = 0.03) in the controls. Flow-mediated dilatation was significantly impa ired in hypertensive elderly patients (6.7 +/- 3.3 vs. 13.3 +/- 1.8% in con trols, p < 0.0001). No significant difference could be found in nitroglycer in-induced dilatation between controls (12.1 +/- 4.9%) and hypertensive eld erly patients (10.2 +/- 6.8%, p = 0.5). On multivariate analysis, flow-medi ated dilatation in hypertensive elderly patients was inversely related to a ging (r = -0.37, p = 0.04) and mean blood pressure (r = -0.57, p = 0.03). Conclusions: Our study showed decreased flow-mediated dilatation with aging even in the healthy controls, and further decline in flow-mediated dilatat ion in hypertensive elderly patients compared with controls. This impairmen t of flow-mediated dilatation in hypertensive elderly patients was related to age and mean blood pressure, indicating that aging and hypertension may independently impair endothelial function in the brachial artery of these p atients.