None listed
Conditions
Brief summary
The purpose of this project is to investigate whether a soluble fibre supplement (an oligosaccharide blend) is effective in improving asthma control and reducing airway inflammation in adults with poorly controlled asthma. Soluble fibre comes from plant based foods (fruits, vegetables, grains) and is not digested until it reaches the bowel. When it reaches the bowel, the bacteria that live there break it down into small molecules, which are known to be beneficial for our immune system. In this study, we hope to gain further insight into the possible health benefits of soluble fibre in adults with poorly controlled asthma. The project involves a 16 week intervention where 32 participants with stable asthma will be allocated to take a high dose of soluble fibre (oligosaccharide blend) in one or two daily doses, a low dose of soluble fibre (oligosaccharide blend) and placebo control (maltodextrin) for 2 weeks, in random order, with a two week washout period between each supplement phase. Subjects will not know which supplement they are receiving throughout the study.
Interventions
This study is a double-blind, randomised, placebo-controlled, 4-way crossover trial including clinically stable asthmatic adults to examine the effect of a soluble fibre supplement (an oligosaccharide blend) on asthma control and airway inflammation.
There are three intervention arms and one placebo arm in this study. Each subject will be randomly allocated to take each treatment/placebo arm in random order for 2 weeks each, with a 2 week wash out period in between each phase of the study.
1.
This study is a double-blind, randomised, placebo-controlled, 4-way crossover trial including clinically stable asthmatic adults to examine the effect of a soluble fibre supplement (an oligosaccharide blend) on asthma control and airway inflammation. There are three intervention arms and one placebo arm in this study. Each subject will be randomly allocated to take each treatment/placebo arm in random order for 2 weeks each, with a 2 week wash out period in between each phase of the study. 1. High dose formulation 1: 12 g/d of total oligosaccharides via (1x6g oligosaccharides and 1x6g placebo) dose in morning and (1x6g oligosaccharides) dose in evening. 2. High dose formulation 2: 12g total oligosaccharides via 1x12g oligosaccharides dose in morning and 1x6g placebo dose in evening. 3. Low dose formulation: 1x6g total oligosaccharides via (1x6g oligosaccharides and 1x6g placebo) in morning and 1x6g dose placebo dose in evening. 4. Placebo control: 18 g/d or equivalent weight to investigational product of maltodextrin powder via 1x12g dose in morning and 1x6g dose in evening. The oligosaccharide blend powder and placebo powder (maltodextrin) will be provided to participants in individual sachets for each dose, to be mixed with water twice daily (morning/evening). This study takes place over 16 weeks. Two weeks prior to the start of the study, and for the duration of the study, participants will consume a fibre controlled diet. This will include consumption of no more than 2 serves of fruits and vegetables per day and consume ½ cup of bran-based cereal per day to avoid constipation, and avoidance of other fibre-rich foods including oats, oat bran, beans, seeds and sources of probiotics such as yoghurt and fermented milk drinks. Participants will be provided with a standardized evening meal (pasta meal), which they will be asked to consume the night before each of their scheduled appointments. They will also be asked to fast for 12-hours prior to the clinic visit. Adherence with the protocol will be monitored by sachet returns and study diaries.
Sponsors
University of Newcastle
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Caregiver, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Males and females aged 18 years and over. Doctor diagnosis of asthma and confirmed airway hyper-responsiveness Poorly controlled asthma, defined as ACQ6 >0.75 units
Exclusion criteria
Recent (past month) respiratory tract infection; respiratory conditions other than asthma; non-adherence to prescribed asthma medications; dietary modifications unsuitable; current diagnosis of diabetes or active gastrointestinal disease; recent antibiotic or laxative use; nutritional, fibre or probiotic supplement use (this includes any vitamin or minerals, sports supplements, meal replacements, probiotics and fibre preparations) within the previous 4 weeks; current smokers; pregnancy or breastfeeding; chronic or excessive alcohol consumption; unexplained weight loss (>5% body weight) in the past 6 months; current use of anti-inflammatory medications (e.g. corticosteroids, nonsteroidal anti-inflammatory drugs (NSAIDS)); terminal illness; galactosemia or ragweed allergy.
Outcome results
None listed