Factor Analysis of Changes in Dyspnea and Lung Function Parameters after Bronchodilation in Chronic Obstructive Pulmonary Disease

摘要

Expiratory airway collapse is a characteristic feature in patients with chronic obstructive pulmonary disease (COPD). We hypothe - sized that this collapse might mask the effects of bronchodilators during forced expiration but not during forced inspiration, and that accordingly, the improvement in forced inspiration and not that in forced expiration with bronchodilator therapy would be re - lated to changes in the perception of dyspnea.