Effects of Tiotropium on Breathing Capacity and Exercise Limitation in Early Stages of Chronic Obstructive Pulmonary Disease

Study Summary

Optimal clinical management in early stages of COPD is not established. Tiotropium has been shown to improve exercise tolerance during (CWR) cycle ergometry with GOLD stage II to IV COPD, improvements in constant speed treadmill time in a study of patients who also received pulmonary rehabilitation in a population of patients with predominantly severe and very severe disease (GOLD stages III and IV) and improvements in exertional dyspnea, and Shuttle Walk Test distance in GOLD stage III and IV COPD. However, data are lacking on the benefits of tiotropium on exercise tolerance in a patients with early stages of COPD who are symptomatic. Patients with milder ventilatory limitations (GOLD stages I/II COPD patients) may benefit from maintenance therapy and there is limited data on exercise limitation in patients with early stage COPD who are symptomatic. This study is designed to evaluate the mechanisms of breathlessness and assess physical activity limitation in early stage COPD patients compared to age and gender matched controls and will secondly investigate the effectiveness of treatment with tiotropium in improving dyspnea during exercise and exercise duration as a result of the bronchodilation effects of tiotropium leading to a reduction of dynamic hyperinflation in Early Stage COPD patients.

Primary Outcome

Inspiratory capacity (IC) during CWR exercise testing measured at isotime (isotime was established during CWR exercise testing at baseline). Isotime is the minimum exercise time among all tests. Constant work rate exercise means the exercise is done under constant work rate.

Interventions

• DRUG Placebo
• DRUG Tiotropium