Dietary Nitrate in COPD

Study Overview
=================
Brief Summary
-----------------
The acute consumption of dietary nitrate has been shown to improve exercise capacity in athletes, healthy adults and subjects with peripheral vascular disease. Many COPD patients have reduced exercise capacity, The investigators hypothesized that acute nitrate consumption, in the form of beetroot juice, might increase incremental shuttle walk test (ISWT) distance in COPD subjects.

Detailed Description
-----------------
Acute consumption of dietary nitrate (as beetroot juice) has been shown to improve exercise capacity in athletes, healthy adults and subjects with peripheral vascular disease. Many COPD patients have reduced exercise capacity, The investigators hypothesized that acute nitrate consumption might increase incremental shuttle walk test (ISWT) distance in COPD subjects compared to a matched, low-nitrate drink. This study is a randomized, double-blind placebo-controlled, crossover trial. Resting blood pressure, phlebotomy and ISWT are performed. Following completion, each subject is randomized to consume beetroot juice or placebo. 3 hours later, the same assessments are repeated by the same people. After a 7d washout, the entire protocol is repeated with the crossover beverage.

Official Title
-----------------
Dietary Nitrate in COPD: A Double-blind, Randomized, Placebo-controlled, Crossover Trial

Conditions
-----------------
Chronic Obstructive Pulmonary Disease

Intervention / Treatment
-----------------
* Dietary Supplement: Nitrate rich beverage
* Dietary Supplement: Nitrate free beverage


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Information consenting out-patients with a previous physician diagnosis of COPD Clinically stable Ambulatory Exclusion Criteria: Subjects who required supplemental oxygen for exercise Subjects with pulmonary hypertension and angina Intolerant to beetroot Insulin dependent diabetes Thyroid disease
Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Nitrate rich beverage<br>Nitrate rich beverage will contain 140ml nitrate rich beetroot juice + 200ml blackcurrant juice containing 12.7mmol nitrate | Dietary Supplement: Nitrate rich beverage<br>* Following randomisation on day 1, subjects will consume either the nitrate or nitrate-free beverage and then the crossover beverage on day 8.<br>* Other names: Nitrate rich beetroot juice;|
| Placebo Comparator: Nitrate free beverage<br>Nitrate free beverage will 140ml water + 200ml blackcurrant juice containing <0.5mmol nitrate | Dietary Supplement: Nitrate free beverage<br>* Following randomisation on day 1, subjects will consume either the nitrate or nitrate-free beverage and then the crossover beverage on day 8.<br>* Other names: Placebo beverage;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Incremental Shuttle Walk Test Distance | The change between day 1, time 0 and day 1, time 3h will be compared to the changes between day 8, time 0 and day 8, time 3h. | day 1, time 0, day 1, time 3h, day 8, time 0, day 8, time 3h | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
COPD, beetroot, dietary nitrate, nitric oxide