The primary criteria is the peripheral endothelial function that will be assessed by the measure of flow-mediated dilation (reactive hyperemia-peripheral artery tone index). The pulmonary function will be assessed by the measures of the FEV1 (forced expiratory volume in one second), the forced vital capacity (FVC) and the expiratory flow between 25% and 75% (FEF25-75%). The relationship between these parameters of the pulmonary function and the peripheral endothelial function will be analyzed. In addition, a relationship between peripheral endothelial function and the severity of COPD (classification according to GOLD (Global Initiative for Chronic Obstructive Lung Disease) 2010 and GOLD 2011 and the COPD assessment test, the cardiovascular risk factors (SCORE INdex) and the smoker status will be also assessed.
