Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12611000235909
Ethics application status
Approved
Date submitted
2/03/2011
Date registered
3/03/2011
Date last updated
22/01/2020
Date data sharing statement initially provided
22/01/2020
Date results information initially provided
22/01/2020
Type of registration
Retrospectively registered

Titles & IDs
Public title
Asthma and Weight Loss: A Dietary and Exercise Intervention to Improve Clinical Asthma Outcomes in Overweight and Obese Participants with Asthma
Scientific title
A Dietary and Exercise Intervention to Improve Clinical Asthma Outcomes in Overweight and Obese Participants with Asthma
Secondary ID [1] 253046 0
None
Universal Trial Number (UTN)
Trial acronym
WLA
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Asthma 261291 0
Obesity 261292 0
Overweight 261293 0
Condition category
Condition code
Respiratory 258754 258754 0 0
Asthma
Diet and Nutrition 259439 259439 0 0
Obesity

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Randomised trial, where participants are randomised to one of three different interventions for 10-weeks:

1. Low-calorie diet: a nutritionally sound diet plan from a qualified dietitian. This intervention includes nutritious meal replacements (i.e. shakes, soups, bars) for two meals per day, a nutritious third main meal and healthy snacks. Participants receive nutrition counselling and have their progress reviewed weekly by a dietitian, either in person for one hour per session (week 0, 1, 2, 5, 8, 9, 10) or over the telephone for 10 minutes per session (week 3, 4, 6, 7).

2. Exercise program: Participants are provided with a 12-week membership at the University of Newcastle gymnasiums at Callaghan campus and Honeysuckle Gym. The intervention itself will go for 10 weeks and the participants will have the option to attend the gymnasium for the additional 2 weeks. Staff will induct participants during their first fortnight of the study and review their progress weekly. The exercise program involves a combination of aerobic activities and some resistance training at least 3 times a week for one hour per session, including one personal training session for one hour/week in a group of up to 5 study participants. The personal trainer is responsible for designing an individualised exercise program for each participant, which is monitored to ensure patient safety. Participants are also instructed to wear a pedometer and encouraged to increase their daily steps by at least 10% each week, to a target of 10,000 steps per day.

3. Combined low-calorie diet and exercise program: Participants are instructed to follow both interventions at once.
Intervention code [1] 257571 0
Behaviour
Intervention code [2] 264157 0
Treatment: Other
Comparator / control treatment
All three groups are intervention groups, providing important and differential effects to asthma outcomes and inflammation. Therefore there is no single control/comparator group for this study.
Control group
Active

Outcomes
Primary outcome [1] 259613 0
Expiratory Reserve Volume (ERV)

This will be assessed by measuring lung volumes using a computerised plethysmograph system (Vmax Encore, Sensormedics Corp., Yorba Linda, Ca, USA) in accordance with American Thoracic Society/European Respiratory Society guidelines. This will be measured at each time point and change will be calculated.
Timepoint [1] 259613 0
Weeks 0, 10 and 20
Primary outcome [2] 262247 0
Quality of Life (QoL)

This will be assessed by administering the Juniper Asthma Quality of Life questionnaire to all subjects at each time point and measuring change in overall QoL score.
Timepoint [2] 262247 0
Weeks 0, 10 and 20
Primary outcome [3] 262261 0
C-reactive protein (CRP)

Blood samples will be collected and a commercial ELISA used to determine the plasma high sensitivity CRP of subjects at each time point. Change will be calculated.
Timepoint [3] 262261 0
Weeks 0, 10 and 20
Secondary outcome [1] 266259 0
Functional Residual Capacity (FRC)

This will be assessed by measuring lung volumes using a computerised plethysmograph system (Vmax Encore, Sensormedics Corp., Yorba Linda, Ca, USA) in accordance with American Thoracic Society/European Respiratory Society guidelines. This will be measured at each time point and change will be calculated.
Timepoint [1] 266259 0
Weeks 0, 10 and 20
Secondary outcome [2] 273413 0
Asthma control questionnaire (ACQ)

This will be assessed by administering the 7 question Juniper Asthma Control Questionnaire (ACQ) to all subjects at each time point and measuring change in overall score.
Timepoint [2] 273413 0
Weeks 0, 10 and 20
Secondary outcome [3] 273414 0
Total body fat change (%)

All participants will undergo a full body dual-energy x-ray absorptiometry (DXA) scan at each timepoint. This will indicate the %total body fat of each participant; change will be calculated from each time point.
Timepoint [3] 273414 0
Weeks 0, 10 and 20
Secondary outcome [4] 273415 0
Sputum %neutrophils

Sputum induction using 4.5% hypertonic saline will be performed over a standardised 15.5 minutes nebuliser time. Lower respiratory sputum portions will then be selected and dispersed using dithiothreitol. Total and differential cell counts will be determined, then sputum %neutrophils calculated from this. Change in sputum %neutrophils will be calculated from each time point.
Timepoint [4] 273415 0
Weeks 0, 10 and 20
Secondary outcome [5] 273416 0
Leptin

Blood samples will be collected and a commercial ELISA used to determine the serum leptin of subjects at each time point. Change will be calculated.
Timepoint [5] 273416 0
Weeks 0, 10 and 20
Secondary outcome [6] 273417 0
Interleukin-6 (IL-6)

Blood samples will be collected and a commercial ELISA used to determine the serum IL-6 of subjects at each time point. Change will be calculated.
Timepoint [6] 273417 0
Weeks 0, 10 and 20

Eligibility
Key inclusion criteria
Adults with a BMI 28-40kg/m2, a doctors diagnosis of asthma and airway hyperresponsiveness to 4.5% hypertonic saline.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Current smoker, following a specialised diet, taking insulin or oral hypoglycaemic medication, pregnant or planning on becoming pregnant during the study period, currently breastfeeding, cardiac arrhythmia, angina, congestive heart failure, renal or hepatic failure, current gallstones, pancreatitis, cancer, an orthopaedic problem that would make it difficult to exercise, a lung disease other than asthma.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Subjects will be screened and assessed for study eligibility by the study coordinator. Once approved for the study, participants will be booked in by the study coordinator to commence in groups of up to five participants. Once an entire group has been booked in and confirmed, the study coordinator will contact the Univeristy statistician via email who will be holding/concealing participants group allocation. The statistician will then reveal to the coordinator the intervention to be completed by that particular study group. Once an intervention has been revealed to the study coordinator, no additional participants may be booked in to that group. Participants will not made aware of their randomisation until all baseline data has been collected.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer generated random numbers have been created to randomise participants within each block. Randomisation codes are held by the University statistician and concealed to all study personnel. Participants are recruited in blocks of up to five participants. Once all participants of a particular block have been confirmed for the study, the randomisation is revealed by the statistician to the study coordinator via email.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
3/06/2009
Actual
8/07/2009
Date of last participant enrolment
Anticipated
Actual
5/10/2010
Date of last data collection
Anticipated
Actual
16/03/2011
Sample size
Target
60
Accrual to date
Final
47
Recruitment in Australia
Recruitment state(s)
NSW
Recruitment postcode(s) [1] 3733 0
2305

Funding & Sponsors
Funding source category [1] 264593 0
Charities/Societies/Foundations
Name [1] 264593 0
Hunter Medical Research Institute
Country [1] 264593 0
Australia
Funding source category [2] 264594 0
Government body
Name [2] 264594 0
NHMRC Centre for Clinical Research Excellence in Respiratory and Sleep Medicine
Country [2] 264594 0
Australia
Primary sponsor type
Individual
Name
Dr Lisa Wood (Chief Investogator)
Address
Department of Respiratory & Sleep Medicine
Level 3, Hunter Medical Research Institute
John Hunter Hospital
Lookout Road
New Lambton Heights NSW 2305
Country
Australia
Secondary sponsor category [1] 263733 0
None
Name [1] 263733 0
Address [1] 263733 0
Country [1] 263733 0
Other collaborator category [1] 251839 0
Individual
Name [1] 251839 0
Hayley Scott (Student Investigator)
Address [1] 251839 0
Department of Respiratory & Sleep Medicine
Level 3, Hunter Medical Research Institute
John Hunter Hospital
Lookout Road
New Lambton Heights NSW 2305
Country [1] 251839 0
Australia
Other collaborator category [2] 251840 0
Individual
Name [2] 251840 0
Jeff Pretto (Co-investigator)
Address [2] 251840 0
Newcastle Sleep Disorders Centre,
Locked Bag 1,
Hunter Region Mail Centre NSW 2310
Country [2] 251840 0
Australia
Other collaborator category [3] 251841 0
Individual
Name [3] 251841 0
Prof Peter Gibson (Co-investigator)
Address [3] 251841 0
Department of Respiratory & Sleep Medicine
Level 3, Hunter Medical Research Institute
John Hunter Hospital
Lookout Road
New Lambton Heights NSW 2305
Country [3] 251841 0
Australia
Other collaborator category [4] 251842 0
Individual
Name [4] 251842 0
Prof Manohar Garg (Co-investigator)
Address [4] 251842 0
School of Biomedical Sciences & Pharmacy, Faculty of Health
305C Medical Science Building
University of Newcastle
Callaghan NSW 2308
Country [4] 251842 0
Australia
Other collaborator category [5] 251843 0
Individual
Name [5] 251843 0
A/Prof Philip Morgan (Co-investigator)
Address [5] 251843 0
School of Education
Faculty of Education and Arts
University of Newcastle

Callaghan NSW 2308
Country [5] 251843 0
Australia
Other collaborator category [6] 251844 0
Individual
Name [6] 251844 0
Prof Robin Callister (Co-investigator)
Address [6] 251844 0
School of Biomedical Sciences & Pharmacy, Faculty of Health
University of Newcastle
Callaghan NSW 2308
Country [6] 251844 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 260586 0
Hunter New England Human Research Ethics Unit
Ethics committee address [1] 260586 0
Hunter New England Human Research Ethics and Governance Unit
Hunter New England Health
Locked Bag 1
New Lambton NSW 2305
Ethics committee country [1] 260586 0
Australia
Date submitted for ethics approval [1] 260586 0
26/02/2009
Approval date [1] 260586 0
30/04/2009
Ethics approval number [1] 260586 0
HREC/09/HNE/77

Summary
Brief summary
Research regarding weight loss in people with asthma is limited. Although preliminary research suggests weight loss improves clinical outcomes in asthmatic subjects, it is mostly of poor quality and better studies are justified. In addition, there is no research examining the mechanism by which weight loss results in these improvements. Our previous cross-sectional data suggests that neutrophilic airway inflammation is increased by obesity, which may worsen asthma. It is therefore important to conduct intervention trials to determine whether this airway inflammation is reversible through weight loss and/or fat loss. This will enable a better understanding of the association between obesity and asthma and would play an important role in asthma management and prevention.

AIM:
To examine the effect of weight loss, via body fat reduction, on systemic and airway inflammation and clinical outcomes in obese asthmatics.

HYPOPTHESIS:
Weight loss, specifically body fat reduction, will reduce inflammation and improve clinical outcomes in obese asthmatics.
Trial website
Trial related presentations / publications
Conference Abstracts:
1. HA Scott, PG Gibson, ML Garg, J Pretto, P Morgan, R Callister, LG Wood. Caloric Restriction and Exercise Improve Clinical Asthma Outcomes in Overweight and Obese Asthma. Australian & New Zealand Obesity Society Annual National Meeting, Sydney, October 2010.

2. HA Scott, PG Gibson, ML Garg, J Pretto, P Morgan, R Callister, LG Wood. Clinical Asthma Outcomes Are Improved By Caloric Restriction and Exercise in Overweight and Obese Asthma. Nutrition Society of Australia Annual Scientific Meeting, Perth, December 2010.

3. HA Scott, PG Gibson, ML Garg, J Pretto, P Morgan, R Callister, LG Wood. Body Fat Reduction Improves Clinical Asthma Outcomes in Overweight and Obese Asthma. The Thoracic Society of Australia & New Zealand Annual Scientific Meeting, Perth, April 2011.

4. HA Scott, PG Gibson, ML Garg, J Pretto, P Morgan, R Callister, LG Wood. Success in a Weight Loss Trial is Related to Asthma Severity. The Thoracic Society of Australia & New Zealand Annual Scientific Meeting, Perth, April 2011.

5. HA Scott, PG Gibson, ML Garg, J Pretto, P Morgan, R Callister, LG Wood. Clinical Asthma Outcomes are Improved After Body Fat Reduction in Overweight and Obese Asthmatics. American Thoracic Society International Conference, Denver USA, May 2011.

6. HA Scott, PG Gibson, ML Garg, J Pretto, P Morgan, R Callister, LG Wood. Success in a Weight Loss Trial is Greatest in Subjects With More Severe Asthma. American Thoracic Society International Conference, Denver USA, May 2011

Peer Reviewed Journal Publications
1. Scott HA, Gibson PG, Garg ML, Pretto JJ, Morgan PJ, Callister R, Wood LG.Determinants of weight loss success utilizing a meal replacement plan and/or exercise, in overweight and obese adults with asthma. Respirology. 2015 Feb;20(2):243-50. doi: 10.1111/resp.12423. Epub 2014 Nov 3.

2. Scott HA, Gibson PG, Garg ML, et al. Dietary restriction and exercise improve airway inflammation and clinical outcomes in overweight and obese asthma: a randomized trial. Clin Exp Allergy 2013;43(1):36-49.

3. Scott HA, Gibson PG, Garg ML, et al. Airway inflammation is augmented by obesity and fatty acids in asthma. Eur Respir J 2011;38(3):594-602.
Public notes
.

Contacts
Principal investigator
Name 31887 0
Prof Lisa Wood
Address 31887 0
Centre for Asthma and Respiratory Diseases
Level 2, West Wing, HMRI Building
Kookaburra Crt
New Lambton Heights, NSW, 2305
AUSTRALIA
Country 31887 0
Australia
Phone 31887 0
+61240420147
Fax 31887 0
+61 2 4042 0046
Email 31887 0
[email protected]
Contact person for public queries
Name 15134 0
Prof Lisa Wood
Address 15134 0
Centre for Asthma and Respiratory Diseases
Level 2, West Wing, HMRI Building
Kookaburra Crt
New Lambton Heights, NSW, 2305
AUSTRALIA
Country 15134 0
Australia
Phone 15134 0
+61240420147
Fax 15134 0
+61 2 40420046
Email 15134 0
[email protected]
Contact person for scientific queries
Name 6062 0
Prof Lisa Wood
Address 6062 0
Centre for Asthma and Respiratory Diseases
Level 2, West Wing, HMRI Building
Kookaburra Crt
New Lambton Heights, NSW, 2305
AUSTRALIA
Country 6062 0
Australia
Phone 6062 0
+61 2 4042 0147
Fax 6062 0
+61 2 4042 0046
Email 6062 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
TypeIs Peer Reviewed?DOICitations or Other DetailsAttachment
Study results articleYes Scott HA, Gibson PG, Garg ML, et al. Dietary restr... [More Details]
Study results articleYes Scott HA, Gibson PG, Garg ML, et al. Relationship ... [More Details]
Study results articleYes Scott HA, Gibson PG, Garg ML, et al. Determinants ... [More Details]

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseDeterminants of weight loss success utilizing a meal replacement plan and/or exercise, in overweight and obese adults with asthma.2015https://dx.doi.org/10.1111/resp.12423
EmbaseResistin is a predictor of asthma risk and resistin:adiponectin ratio is a negative predictor of lung function in asthma.2016https://dx.doi.org/10.1111/cea.12742
N.B. These documents automatically identified may not have been verified by the study sponsor.