Effect of Increased Fruit and Vegetable Intake on Chronic Obstructive Pulmonary Disease (COPD) (DISCO)

Effect of Increased Fruit and Vegetable Intake on Airway Inflammation and Oxidative Stress in Chronic Obstructive Pulmonary Disease (COPD)

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.

Study Overview

• Status: Completed
• Conditions: Chronic Obstructive Pulmonary Disease
• Intervention / Treatment: Behavioral: 5 portions fruit and vegetables/day

• Study Type: Interventional
• Enrollment (Actual): 81
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Co.Antrim
    • Belfast, Co.Antrim, United Kingdom, BT12 6BJ
      • Queen's University Belfast

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Low fruit and vegetables; Control - two or less portions fruit and vegetables/day
Experimental: High fruit and vegetables; 5 portions fruit and vegetables/day	Behavioral: 5 portions fruit and vegetables/day; Participants consume > = 5 portions fruit and veg per day

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
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;	12 weeks
Markers of Airway Inflammation in Induced Sputum - Sputum 8-isoprostane	Markers of Airway Inflammation in Induced Sputum - Sputum 8-isoprostane ng/ml	12 Weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Biochemical Markers of Nutritional Status Plasma Vitamin C	Plasma vitamin C concentration umol/L	12 weeks

Collaborators and Investigators

• Sponsor: Queen's University, Belfast
• Investigators: Principal Investigator: Ian Young, MD, Queen's University, Belfast

Publications and helpful links

General Publications

• Baldrick FR, Elborn JS, Woodside JV, Treacy K, Bradley JM, Patterson CC, Schock BC, Ennis M, Young IS, McKinley MC. Effect of fruit and vegetable intake on oxidative stress and inflammation in COPD: a randomised controlled trial. Eur Respir J. 2012 Jun;39(6):1377-84. doi: 10.1183/09031936.00086011. Epub 2011 Nov 16.

Study record dates

Study Major Dates

• Study Start: February 1, 2007
• Primary Completion (Actual): September 1, 2009
• Study Completion (Actual): September 1, 2009

Study Registration Dates

• First Submitted: February 14, 2007
• First Submitted That Met QC Criteria: February 14, 2007
• First Posted (Estimated): February 15, 2007

Study Record Updates

• Last Update Posted (Actual): July 31, 2024
• Last Update Submitted That Met QC Criteria: February 16, 2024
• Last Verified: February 1, 2024

More Information

Terms related to this study

• Keywords: Oxidative stress; Inflammation; COPD; Fruit; Vegetables
• Additional Relevant MeSH Terms: Pathologic Processes; Respiratory Tract Diseases; Disease Attributes; Chronic Disease; Lung Diseases; Lung Diseases, Obstructive; Pulmonary Disease, Chronic Obstructive
• Other Study ID Numbers: Ref 200651