Extrait

Background and study aims Patients with chronic obstructive pulmonary disease (COPD), which is a combination of chronic bronchitis and emphysema, are limited in their daily activates because of breathlessness. However, there is increasing evidence that their muscle function is also reduced which can further limit them, so we are investigating a dietary supplement that may be helpful. Muscle metabolism and blood flow are influenced by a substance called nitric oxide (NO). Levels of this can be influenced by dietary nitrate consumption (found in leafy green vegetables and especially in beetroot). There is evidence that beetroot juice can improve exercise performance in athletes and we want to test whether it will improve exercise performance in people with COPD. Who can participate? We will study 25 people with COPD. What does the study involve? After baseline assessments of lung function and exercise capacity, patients will perform two maximum exercise tests. One after consuming 70mls of beetroot juice and one after consuming 70mls of beetroot juice treated to remove the nitrate (placebo). They taste identical and patients and researchers will not know which they have consumed. The primary endpoint (or (measure of success) of the study is the time that patients can cycle on a bike in our laboratory at a workload that is 70% of the maximum they can reach. Oxygen consumption and muscle metabolism (using a technique called near infrared spectroscopy) will be assessed. We will take blood samples to monitor the effect of the juice/placebo on nitrate levels. What are the possible benefits and risks of participating? The procedures are all routine so no risks are anticipated: If positive, this initial study would lead to a larger research study to evaluate the use of this supplement more widely in patients with COPD. Where is the study run from? The study is being performed at The Royal Brompton Hospital and is supported by Imperial College (UK). When is the study starting and how long is it expected to run for? It is expected to run from the beginning of May 2013 until the end of 2014. Who is funding the study? It is funded from Royal Brompton Hospital Departmental funds (UK). Who is the main contact? Dr Nicholas Hopkinson [email protected]

Critère d'inclusion

• Chronic Obstructive Pulmonary Disease (COPD)

Liens

• isrctn
• ictrp