Chronic Obstructive Pulmonary Disease
Conditions
Keywords
COPD, Fruit, Vegetables, Oxidative stress, Inflammation
Brief summary
Chronic obstructive pulmonary disease (COPD) is the UK's fastest growing fatal disease and is estimated to cost the health service close to £1 billion every year. Around 80,000 people in Northern Ireland suffer from COPD. COPD is clinically defined as a slowly progressive condition characterised by airflow limitation, which is largely irreversible. Chronic inflammation and oxidative stress are key components of the underlying pathological process resulting in airflow limitation. Dietary factors and nutrients that have antioxidant or anti-inflammatory properties are therefore of interest with respect to the aetiology of COPD. The antioxidant vitamins C, E and beta-carotene are all present in the lung milieu. Such antioxidants represent the lung's first line of defence against oxygen free radicals. Observational studies indicate that a low dietary intake of antioxidant nutrients, or foods rich in antioxidants (e.g. fruit and vegetables), is associated with decreased lung function and increased risk of COPD. To date, there have been no food-based dietary interventions investigating the effect of increased fruit and vegetable intake on COPD. The investigators propose to recruit people with mild to moderate COPD and low fruit and vegetable intakes (\<=2 portions daily) and randomise them to one of two study arms for 12 weeks - either to increase fruit and vegetable consumption to at least 5 portions a day, or to follow their normal diet. Airway and systemic oxidative stress and inflammation will be assessed at baseline and post-intervention in order to determine if fruit and vegetables have the potential to alleviate the oxidative stress and airway inflammation associated with COPD.
Interventions
BEHAVIORAL5 portions fruit and vegetables/day
Participants consume \> = 5 portions fruit and veg per day
Sponsors
Queen's University, Belfast
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Healthy volunteers
No
Inclusion criteria
* moderate to severe COPD (according to GOLD classification) * oxygen saturation \>= 92 KPa * symptomatically stable * habitually low fruit and vegetable intakes (\<=2 portions daily) * exercise limited by shortness of breath (rather than e.g. angina, arthritis)
Exclusion criteria
* diabetes * taking antioxidant supplements or drugs * oxygen saturation \<8KPa
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Self-reported Intake of Fruit and Vegetables (Number of Portions Per Day); | 12 weeks | A series of 7-day diet histories were completed by each participant at weeks 0 and 12 in order to assess baseline diet and self-reported compliance with the intervention; average daily FV intake was then hand-counted from these records; |
| Markers of Airway Inflammation in Induced Sputum - Sputum 8-isoprostane | 12 Weeks | Markers of Airway Inflammation in Induced Sputum - Sputum 8-isoprostane ng/ml |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Biochemical Markers of Nutritional Status Plasma Vitamin C | 12 weeks | Plasma vitamin C concentration umol/L |
Countries
United Kingdom
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Low FV Group Control - two or less portions fruit and vegetables/day | 41 |
| High FV Group 5 portions fruit and vegetables/day
5 portions fruit and vegetables/day: Participants consume \> = 5 portions fruit and veg per day | 40 |
| Total | 81 |
Baseline characteristics
| Characteristic | Low FV Group | High FV Group | Total |
|---|---|---|---|
| Age, Continuous | 61.2 years STANDARD_DEVIATION 8.3 | 63.2 years STANDARD_DEVIATION 9.1 | 62.2 years STANDARD_DEVIATION 8.71 |
| Region of Enrollment United Kingdom | 41 participants | 40 participants | 81 participants |
| Sex: Female, Male Female | 16 Participants | 19 Participants | 35 Participants |
| Sex: Female, Male Male | 25 Participants | 21 Participants | 46 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 41 | 0 / 40 |
| other Total, other adverse events | 0 / 41 | 0 / 40 |
| serious Total, serious adverse events | 0 / 41 | 0 / 40 |
Outcome results
Primary
Markers of Airway Inflammation in Induced Sputum - Sputum 8-isoprostane
Markers of Airway Inflammation in Induced Sputum - Sputum 8-isoprostane ng/ml
Time frame: 12 Weeks
| Arm | Measure | Value (GEOMETRIC_MEAN) |
|---|---|---|
| Control | Markers of Airway Inflammation in Induced Sputum - Sputum 8-isoprostane | 1.70 ng/ml |
| Intervention | Markers of Airway Inflammation in Induced Sputum - Sputum 8-isoprostane | 1.83 ng/ml |
Primary
Self-reported Intake of Fruit and Vegetables (Number of Portions Per Day);
A series of 7-day diet histories were completed by each participant at weeks 0 and 12 in order to assess baseline diet and self-reported compliance with the intervention; average daily FV intake was then hand-counted from these records;
Time frame: 12 weeks
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Control | Self-reported Intake of Fruit and Vegetables (Number of Portions Per Day); | 1.9 Portions per day | Standard Deviation 0.5 |
| Intervention | Self-reported Intake of Fruit and Vegetables (Number of Portions Per Day); | 6.1 Portions per day | Standard Deviation 1.8 |
Secondary
Biochemical Markers of Nutritional Status Plasma Vitamin C
Plasma vitamin C concentration umol/L
Time frame: 12 weeks
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Control | Biochemical Markers of Nutritional Status Plasma Vitamin C | 33.44 umol/l | Standard Deviation 21.19 |
| Intervention | Biochemical Markers of Nutritional Status Plasma Vitamin C | 47.64 umol/l | Standard Deviation 19.23 |