Healthy Eating Better Breathing: A Feeding Study in Patients With Asthma

Dietary Interventions in Asthma Treatment:Healthy Eating Better Breathing Asthma Diet Pilot Study

The study is a randomized, crossover meal-replacement pilot intervention to determine feasibility of a larger scale dietary trial in asthma and gather preliminary evidence for the impact of a healthy diet on asthma outcomes. Participants with doctor-diagnosed asthma were randomized to crossover trial of a 4-week dietary intervention or usual diet with a 4-week washout period. During the dietary intervention, all meals and snacks were provided by the study.

Study Overview

• Status: Completed
• Conditions: Asthma
• Intervention / Treatment: Other: healthy diet

Detailed Description

The objective of the study is to demonstrate feasibility of a randomized, controlled clinical trial of a dietary intervention in a population of adults with asthma and to determine sample size estimates for a larger, more definitive trial aimed at improving asthma clinical outcomes and improving markers of inflammation and oxidative stress. The study uses a feeding trial design comprised of a 4 week dietary intervention in which all meals are provided to study participants and a 4 week control diet comprised of usual dietary intake. Participants are randomized to the intervention or control diet and then cross over to the alternate assignment after a 4 week washout period.

• Study Type: Interventional
• Enrollment (Actual): 19
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 50 years (ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• ages 18-50, self-reported physician diagnosis and treatment for asthma within the 12 months prior to enrollment, stable asthma defined as no asthma exacerbation (emergency department visit, systemic steroid treatment, or urgent care visit) or respiratory infection in the 4 weeks prior to enrollment.

Exclusion Criteria:

• active smokers,pregnant or breastfeeding, using systemic corticosteroids or warfarin, had another major pulmonary diagnosis or significant systemic illness, reported excessive alcohol consumption (over 14 drinks per week or six or more drinks on one or more occasions per week), reported food allergy, or weighed over 350 pounds or changed weight by over ten pounds in the two months prior to screening

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: NONE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: healthy diet; Participants were provided all meals and snacks for four weeks. Menus were created to target a healthy diet high in unsaturated fats.	Other: healthy diet; Participants were provided meals and snacks for one month that represented a healthy diet that is high in unsaturated fats, approximating a Mediterranean diet
No Intervention: control diet; Participants were instructed to consume their usual diet.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Feasibility as assessed by the number of participant drop outs	Feasibility will be assessed by the number of drop outs.	Change from baseline and 4 weeks
Adherence using 24 hour diet recall	Adherence to the dietary intervention will be assessed using self-report of dietary intake via 24 hour dietary recall.	Change from baseline to 4 weeks
Adherence assessed by serum carotenoids	Serum carotenoids will be measured at baseline and at 4 weeks. An increase in serum carotenoids is expected with adherence to the dietary intervention.	Change from baseline to 4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
FEV1	Spirometry will be measured according to the American Thoracic Society standards. The forced expiratory volume in one second (FEV1) will be assessed and compared between baseline and 4 weeks after the dietary intervention	Difference between baseline and 4 weeks
FEV1	Spirometry will be measured according to the American Thoracic Society standards. The forced expiratory volume in one second (FEV1) will be assessed and compared between baseline and 2 weeks after the dietary intervention	Difference between baseline and 2 weeks
FVC	Spirometry will be measured according to the American Thoracic Society standards. The forced vital capacity (FVC) will be assessed and compared between baseline and 4 weeks after the dietary intervention	Difference between baseline and 2 weeks
FVC	Spirometry will be measured according to the American Thoracic Society standards. The forced vital capacity (FVC) will be assessed and compared between baseline and 4 weeks after the dietary intervention	Difference between baseline and 4 weeks
FEV1/FVC ratio	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 and compared between baseline and 4 weeks after the dietary intervention	Difference between baseline and 4 weeks
FEV1/FVC ratio	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 and compared between baseline and 2 weeks after the dietary intervention	Difference between baseline and 2 weeks
Asthma status	Asthma Control Test (ACT, range 5-25, higher score denoting better asthma control). The change in score between baseline and week 4 will be assessed.	Difference between baseline and 4 weeks
Asthma status	Asthma Control Test (ACT, range 5-25, higher score denoting better asthma control). The change in score between baseline and week 2 will be assessed.	Difference between baseline and 2 weeks
Asthma Symptom Utility Index	Asthma Symptom Utility Index (ASUI, range 0-1, higher score denoting fewer symptoms) will be measured and the difference between week 4 and week 0 will be assessed.	Difference between baseline and 4 weeks
Asthma Symptom Utility Index	Asthma Symptom Utility Index (ASUI, range 0-1, higher score denoting fewer symptoms) will be measured and the difference between week 2 and week 0 (baseline) will be assessed.	Difference between baseline and 2 weeks
Asthma Quality of Life Questionnaire (AQLQ)	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). Scores between week 0 (baseline) and week 4 will be assessed.	Difference between baseline and 4 weeks
Asthma Quality of Life Questionnaire (AQLQ)	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). Scores between week 0 (baseline) and week 2 will be assessed.	Difference between baseline and 2 weeks
Exhaled nitric oxide	Exhaled nitric oxide is an indicator of airway inflammation and will be measured according to American Thoracic Society standards at baseline and 4 weeks.	Difference between baseline and 4 weeks
Exhaled nitric oxide	Exhaled nitric oxide is an indicator of airway inflammation and will be measured according to American Thoracic Society standards at baseline and 2 weeks.	Difference between baseline and 2 weeks
Adherence assessed by serum carotenoids	Serum carotenoids will be measured at baseline and at 4 weeks. An increase in serum carotenoids is expected with adherence to the dietary intervention.	Difference between baseline and 2 weeks

Collaborators and Investigators

• Sponsor: Johns Hopkins University

Study record dates

Study Major Dates

• Study Start: September 1, 2012
• Primary Completion (Actual): February 1, 2013
• Study Completion (Actual): February 1, 2013

Study Registration Dates

• First Submitted: September 9, 2016
• First Submitted That Met QC Criteria: September 13, 2016
• First Posted (Estimate): September 19, 2016

Study Record Updates

• Last Update Posted (Estimate): September 23, 2016
• Last Update Submitted That Met QC Criteria: September 21, 2016
• Last Verified: September 1, 2016

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Immune System Diseases; Lung Diseases; Hypersensitivity, Immediate; Bronchial Diseases; Lung Diseases, Obstructive; Respiratory Hypersensitivity; Hypersensitivity; Asthma
• Other Study ID Numbers: NA_00071879

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO