None listed
Conditions
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.
Interventions
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
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.
Sponsors
Dr Lisa Wood (Chief Investogator)
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Adults with a BMI 28-40kg/m2, a doctors diagnosis of asthma and airway hyperresponsiveness to 4.5% hypertonic saline.
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.
Outcome results
None listed