Asthma
Conditions
Keywords
ketone, diet, metabolism
Brief summary
Determine to what extent three distinct dietary approaches improve asthma control and lung function.
Detailed description
This is a crossover design pilot trial that will recruit 15 adults with asthma. Participants will undergo screening and a lead-in period before being randomized to a series of three, 7-day diets with a 7+ day washout period between each diet. Asthma control and lung function will be assessed at the completion of each diet. The goal of this pilot trial is to understand the effect of diet on asthma and conduct an exploratory analysis on factors that may predict the response to diet.
Interventions
OTHERDGA Diet
A fully provisioned isocaloric, isonitrogenous study diet following the Dietary Guidelines for Americans (DGA) Including: * A variety of vegetables and fruits * Grains, at least half of which are whole grains * Fat-free or low-fat dairy * A variety of protein foods, including seafood, lean meats and poultry, eggs, legumes, nuts, and seeds * This healthy eating pattern also limits saturated fats and trans fats, added sugars, and sodium.
OTHERMCT Diet
A fully provisioned isocaloric, isonitrogenous study diet following the Dietary Guidelines for Americans supplemented with medium chain triglycerides (MCT).
OTHERKETO Diet
A fully provisioned isocaloric, isonitrogenous ketogenic study diet.
Sponsors
National Heart, Lung, and Blood Institute (NHLBI)
Pennington Biomedical Research Center
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Masking description
Participants will not be made aware of the diet allocation. However, due inherent differences in macronutrient content of the diets, participants may perceive differences in the quantity of various food groups or in the taste, texture or smell of foods present in the diet. To address this, diets will be designed to minimize noticeable differences for the participant. The investigator and outcomes assessor will remain fully masked to diet provision.
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Age: 18-65 years * BMI: 18.5 - 29.99 kg/m2 * asthma diagnosed by medical specialist (confirmed in medical history) * partly controlled or uncontrolled asthma by Asthma Control Test score ≤22 * owns a device compatible with ZEPHYRx platform * stable asthma medication use (no change in the past 2 months).
Exclusion criteria
* Diabetes or using diabetes medications that may lower blood glucose levels * point of care fasting blood glucose ≥126 mg/dl or triglycerides ≥400 mg/dl * current smoking or smoking history of greater than 10 pack-years * other significant respiratory or cardiac disease or the presence of clinically important comorbidities, e.g., COPD, renal failure, liver disease; uncontrolled hypertension defined as systolic blood pressure ≥160 mm/Hg, or diastolic blood pressure ≥100 mm/Hg * pregnant or nursing women * food preferences or allergies inconsistent with study diet capabilities * noncompliance with lead-in period requirements.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Asthma Control | Baseline | Asthma Control Questionnaire score (Juniper; 1 week recall period) Score range: 0-6. Minimally important difference = 0.5. |
| Lung Function | Baseline | FEV1 (forced expiratory volume in 1 second; % of predicted) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Systemic inflammation | Baseline | plasma interleukin-6 (IL6) |
| FENO | Baseline | FENO (ppm) |
| FEV1/FVC | Baseline | FEV1/Forced Vital Capacity (FVC) ratio |
Other
| Measure | Time frame | Description |
|---|---|---|
| ketosis | baseline, after 7 days on Diet#1, after 7 days on Diet#2, after 7 days on Diet#3 | plasma ß-hydroxybutyrate (mM) |
| eosinophilic asthma characterization | baseline, after 7 days on Diet#1, after 7 days on Diet#2, after 7 days on Diet#3 | absolute blood eosinophils (count) |
| systemic inflammation | baseline, after 7 days on Diet#1, after 7 days on Diet#2, after 7 days on Diet#3 | blood cytokines (IL17, TNFα, IL1ß) |
| immunoglobulin asthma characterization | baseline, after 7 days on Diet#1, after 7 days on Diet#2, after 7 days on Diet#3 | blood immunoglobulin E (IgE) |
| indirect calorimetry | baseline, after 7 days on Diet#1, after 7 days on Diet#2, after 7 days on Diet#3 | nutrient utilization according to respiratory exchange ratio (0.66 - 1.0) |
Countries
United States
Contacts
Primary ContactJacob T Mey, PhD, RD
Backup ContactJohn P Kirwan, PhD
Outcome results
None listed