Research Article Serum Superoxide Dismutase Is Associated with Vascular Structure and Function in Hypertensive and Diabetic Patients Manuel A. Gómez-Marcos, 1 Ana M. Blázquez-Medela, 2 Luis Gamella-Pozuelo, 2 José I. Recio-Rodriguez, 1 Luis García-Ortiz, 1 and Carlos Martínez-Salgado 2,3 1 Research Unit, Primary Care Centre La Alamedilla, SACYL, Avenida de los Comuneros 27, 37003 Salamanca, Spain 2 Institute of Biomedical Research of Salamanca (IBSAL), Renal and Cardiovascular Pathophysiology Unit, Department of Physiology and Pharmacology, University of Salamanca, Avenida Campo Charro s/n, 37007 Salamanca, Spain 3 Institute of Studies in Health Sciences of Castilla y Le´ on (IECSCYL), Research Unit, University Hospital of Salamanca, Paseo San Vicente 58-182, 37007 Salamanca, Spain Correspondence should be addressed to Carlos Mart´ ınez-Salgado; carlosms@usal.es Received 17 February 2015; Revised 9 June 2015; Accepted 14 June 2015 Academic Editor: Mat´ ıas Mosqueira Copyright © 2016 Manuel A. G´ omez-Marcos et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Oxidative stress is associated with cardiac and vascular defects leading to hypertension and atherosclerosis, being superoxide dismutase (SOD) one of the main intracellular antioxidant defence mechanisms. Although several parameters of vascular function and structure have a predictive value for cardiovascular morbidity-mortality in hypertensive patients, there are no studies on the involvement of SOD serum levels with these vascular parameters. Tus, we assessed if SOD serum levels are correlated with parameters of vascular function and structure and with cardiovascular risk in hypertensive and type 2 diabetic patients. We enrolled 255 consecutive hypertensive and diabetic patients and 52 nondiabetic and nonhypertensive controls. SOD levels were measured with an enzyme-linked immunosorbent assay kit. Vascular function and structure were evaluated by pulse wave velocity, augmentation index, ambulatory arterial stifness index, and carotid intima-media thickness. We detected negative correlations between SOD and pressure wave velocity, peripheral and central augmentation index and ambulatory arterial stifness index, pulse pressure, and plasma HDL-cholesterol, as well as positive correlations between SOD and plasma uric acid and triglycerides. Our study shows that SOD is a marker of cardiovascular alterations in hypertensive and diabetic patients, since changes in its serum levels are correlated with alterations in vascular structure and function. 1. Introduction Hypertension is quantitatively the most important risk factor for premature cardiovascular disease; essential hypertension and diabetes are characterized by endothelial dysfunction mediated by an impaired NO availability secondary to oxida- tive stress production [1]. Vascular disease is one of the main causes for disability and death in patients with diabetes mellitus [2], which invariably show endothelial dysfunction as well as associated cardiovascular risk factors as hyper- tension, obesity, and dyslipidemia [3]. Either dyslipidemia, hyperinsulinemia, insulin resistance, or hyperglycemia con- tributes to the development of endothelial dysfunction [4]. Arterial stifness, estimated by pulse wave velocity (PWV) determination, has an independent predictive value for cardiovascular events [5], is associated with the severity of coronary artery disease, and is impaired in coronary atherosclerosis [6]. Te ambulatory arterial stifness index (AASI) is related to cardiovascular morbidity-mortality [7] and to the associated target organ damage in hypertensive patients [8]. AASI is very useful for assessing arterial stifness and is an independent predictor of cardiovascular mortality and morbidity in patients with cardiovascular disease and in healthy individuals. We have previously shown that AASI is positively correlated with carotid intima-media thickness (IMT) and PWV and negatively correlated with glomerular fltration [9]. Another parameter to measure wave refection Hindawi Publishing Corporation Oxidative Medicine and Cellular Longevity Volume 2016, Article ID 9124676, 8 pages http://dx.doi.org/10.1155/2016/9124676