BREATHE-Easy Trial
- Conditions
- Asthma
- Interventions
- Other: Prudent dietOther: Western diet
- Registration Number
- NCT03200522
- Lead Sponsor
- Johns Hopkins University
- Brief Summary
This research is being done to evaluate the feasibility of a prudent versus Western diet feeding study in women with asthma in Baltimore City. The results of this research will provide data to appropriately design a definitive study looking at the differential effects of these two diets on asthma health.
- Detailed Description
The investigators are interested in the effects of two different diets on asthma health. The first, a prudent diet, consists of a high intake of fruits and vegetables, whole grains, fiber, omega-3 fatty acids, low-fat dairy products, and overall high levels of antioxidants (which may protect the lungs and the body against inflammation in patients with asthma). The second, a Western diet, consists of a high intake of processed foods, fast foods, sweets, omega-6 fatty acids, and a low intake of fiber (which may promote inflammation in the lungs and the body of patients with asthma).
This pilot study will test the feasibility/acceptability of the study design in providing these two diets to participants over a short period of time (6 days per diet), and gather preliminary data on asthma health outcomes that will be used to design a larger, definitive trial. Each participant will be randomly (by chance, like flipping a coin) assigned to start with one of these diets. All foods in each of the diets will be supplied by the study, and participants will be expected to eat all of the food provided and only the food provided for the next 6 days. The investigators will make sure that each participant gets enough food for what their body needs, based on a visit with a nutritionist at the beginning of the study. After eating either the Prudent diet or Western diet for 6 days, participants will have a 4-8 week break (or washout period), during which they will eat their usual diet. Then participants will begin the alternate dietary intervention (Prudent or Western) for another 6 days, depending on which they received first. Before and after each dietary period, researchers will ask questions, check lung function, and collect samples from participants to determine acceptability of the meals and study design, gather feedback on the intervention and overall study structure, assess for changes in lung health and asthma control, measure inflammation and oxidative stress in the lungs and systemic circulation, and evaluate changes in the airway and gut microbiome associated with the interventions that may influence the asthmatic response.
Recruitment & Eligibility
- Status
- TERMINATED
- Sex
- Female
- Target Recruitment
- 3
Not provided
Not provided
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Prudent diet then Western diet Prudent diet Participants randomized to this arm will received 6 days of meals consistent with a Prudent diet, followed by a washout period, and then 6 days of meals consistent with a Western diet. Western diet then Prudent diet Prudent diet Participants randomized to this arm will received 6 days of meals consistent with a Western diet, followed by a washout period, and then 6 days of meals consistent with a Prudent diet. Western diet then Prudent diet Western diet Participants randomized to this arm will received 6 days of meals consistent with a Western diet, followed by a washout period, and then 6 days of meals consistent with a Prudent diet. Prudent diet then Western diet Western diet Participants randomized to this arm will received 6 days of meals consistent with a Prudent diet, followed by a washout period, and then 6 days of meals consistent with a Western diet.
- Primary Outcome Measures
Name Time Method Feasibility: adherence to diet Completed daily during each of the two, 6-day feeding periods. Daily adherence diaries completed by each participant during each dietary intervention.
Feasibility: participant feedback At conclusion of second feeding period, 7-14 weeks post-enrollment We will measure this via questionnaire at the final study visit.
Feasibility: serum carotenoids Difference between day 1 and day 7 of each feeding period Serum carotenoids will be measured the morning prior to initiating each feeding period and the morning following completion of each 6-day feeding period.
Feasibility: serum lipids Difference between day 1 and day 7 of each feeding period Serum lipids will be measured the morning prior to initiating each feeding period and the morning following completion of each 6-day feeding period.
Feasibility: serum free fatty acids Difference between day 1 and day 7 of each feeding period Serum free fatty acids will be measured the morning prior to initiating each feeding period and the morning following completion of each 6-day feeding period.
Feasibility: obtaining sputum samples Difference between baseline levels and levels on day 7 of each feeding period. Induced sputum will be collected for analysis of airway inflammation, a proposed key outcome for a definitive future trial.
- Secondary Outcome Measures
Name Time Method FEV1 Difference between day 1 and day 7 of each feeding period Spirometry will be measured according to the American Thoracic Society standards. The forced expiratory volume in one second (FEV1) will be assessed.
Daily symptoms Completed daily during each of the two, 6-day feeding periods. Daily symptom diaries completed by each participant during each dietary intervention.
FEV1/FVC ratio Difference between day 1 and day 7 of each feeding period Spirometry will be measured according to the American Thoracic Society standards. The forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) ratio will be assessed.
Albuterol inhaler (rescue medication) use Completed daily during each of the two, 6-day feeding periods. Daily diaries of self-reported albuterol use completed by each participant during each dietary intervention.
Asthma Quality of Life Questionnaire (AQLQ) Difference between baseline levels and levels on day 7 of each feeding period. Asthma Quality of Life Questionnaire (AQLQ) is a 32 item questionnaire and each question uses a 7-point Likert scale (7 = not impaired at all - 1 = severely impaired).
Asthma Symptom Utility Index (ASUI) Difference between day 1 and day 7 of each feeding period Asthma Symptom Utility Index (ASUI, range 0-1, higher score denoting fewer symptoms) will be measured.
Asthma Control Test (ACT) Difference between baseline levels and levels on day 7 of each feeding period. Asthma Control Test (ACT, range 5-25, higher score denoting better asthma control).
FVC Difference between day 1 and day 7 of each feeding period Spirometry will be measured according to the American Thoracic Society standards. The forced vital capacity (FVC) will be assessed.
Exhaled nitric oxide Difference between day 1 and day 7 of each feeding period. Exhaled nitric oxide is an indicator of airway inflammation and will be measured according to American Thoracic Society standards.
Markers of systemic Th1 inflammation Difference between day 1 and day 7 of each feeding period. Serum will be assessed for markers of Th1 inflammation.
Markers of airway Th1 inflammation Difference between baseline levels and levels on day 7 of each feeding period. Sputum will be assessed for markers of Th1 inflammation.
Gut microbiome Difference between microbial community composition on day 1 and day 7 of each feeding period. Microbiome assessment via stool collection.
Markers of airway Th2 inflammation Difference between baseline levels and levels on day 7 of each feeding period. Sputum will be assessed for markers of Th2 inflammation.
Upper airway microbiome Difference between microbial community composition on day 1 and day 7 of each feeding period. Microbiome assessment via nasal swab collection.
Markers of systemic Th2 inflammation Difference between day 1 and day 7 of each feeding period. Serum and urine will be assessed for markers of Th2 inflammation.
Markers of systemic oxidative stress Difference between day 1 and day 7 of each feeding period. Serum and urine will be assessed for markers of oxidative stress.
Markers of airway oxidative stress Difference between baseline levels and levels on day 7 of each feeding period. Sputum will be assessed for markers of oxidative stress.
Lower airway microbiome Difference in microbial community composition between baseline and day 7 of each feeding period. Microbiome assessment via sputum collection.
Trial Locations
- Locations (1)
Johns Hopkins University
🇺🇸Baltimore, Maryland, United States