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Trial registered on ANZCTR


Registration number
ACTRN12609000258257
Ethics application status
Approved
Date submitted
23/04/2009
Date registered
13/05/2009
Date last updated
10/12/2015
Type of registration
Retrospectively registered

Titles & IDs
Public title
A pseudo-randomised dietary intervention to evaluate the effects of a high protein diet on weight loss, body composition and other health outcomes in obese individuals who have gastric banding surgery.
Scientific title
A pseudo-randomised dietary intervention to evaluate the effects of a high protein diet on weight loss, body composition and other health outcomes in obese individuals who have gastric banding surgery.
Secondary ID [1] 251973 0
NA
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obesity 4581 0
Condition category
Condition code
Diet and Nutrition 4877 4877 0 0
Obesity

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The intervention involves a high protein diet for 26 weeks (6 months) following surgery. The intervention diet has been designed to provide approximately: 4500-5000kJ, 90-100g protein, 110g carbohydrate and 30g fat per day. This provides a macronutrient composition of approximately 35% protein, 40% carbohydrate and 25% fat. Participants will commence the intervention within 3 weeks of having surgery and according to clinical assessment. The intervention includes high protein food and drink choices and a powder-based whey protein supplement. Participants will be asked to have 3 level tablespoons of the supplement daily, providing approximately 12g of protein per day. The supplement can be mixed with regular foods and drinks and either consumed as a dispersed dose (eg one tablespoon three times per day) or as one 3 tablespoon dose, determined at the convenience of the participant. Participants will also continue to receive usual dietetic care in addition to the research intervention. Usual dietetic care consists of regular follow-up with a gastric banding dietitian, who provides individualised advice on food, nutrition and activity as appropriate for gastric banding. This will be administered via face-to-face and telephone consultations (of approximately 30 minutes duration) which will occur approximately every 2-6 weeks after surgery. Specific frequency and duration of consultations is determined by the gastric banding dietitian according to individual need.
Intervention code [1] 4344 0
Lifestyle
Comparator / control treatment
Usual dietetic care. Usual dietetic care consists of regular follow-up with a gastric banding dietitian, who provides individualised advice on food, nutrition and activity as appropriate for gastric banding. This will be administered via face-to-face and telephone consultations (of approximately 30 minutes duration) which will occur approximately every 2-6 weeks after surgery. Specific frequency and duration of consultations is determined by the gastric banding dietitian according to individual need.
Control group
Active

Outcomes
Primary outcome [1] 5726 0
Change in body composition (fat mass, fat free mass).
Body composition will be assessed using Dual x-ray absorptiometry (DXA) (Lunar Prodigy, GE Healthcare) in a subset of participants who meet the weight limitation criteria for the DXA equipment (134kg). All participants will also have body composition measured via bioimpedance analysis (BIA) using BIA scales (Tanita BF-310).
Timepoint [1] 5726 0
DXA will be undertaken at baseline, six and 12 months.
BIA will be undertaken at baseline, three, six and 12 months.
Primary outcome [2] 5727 0
Change in body weight. Weight will be measured using digital scales correct to one decimal place (Tanita BF-310). Changes will be calculated as percentage difference from baseline.
Timepoint [2] 5727 0
Baseline, three, six and 12 months
Secondary outcome [1] 241662 0
Resting energy expenditure. This will be measured by indirect calorimetry using a ventilated hood system.
Timepoint [1] 241662 0
Baseline, six and 12 months.
Secondary outcome [2] 241663 0
Blood lipid profile [total cholesterol, low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol and triglycerides (TGs)]. This will be analysed from fasting blood samples.
Timepoint [2] 241663 0
Baseline, three, six and 12 months
Secondary outcome [3] 241664 0
Glucose metabolism (fasting insulin and glucose levels). This will be analysed from fasting blood samples. Homeostasis model assessment (HOMA) will be calculated from fasting glucose and insulin values as a surrogate index of insulin resistance.
Timepoint [3] 241664 0
Baseline, three, six and 12 months

Eligibility
Key inclusion criteria
- Undergoing or have undergone gastric banding no later than two weeks prior to study entry. - Body Mass Index (BMI) > 30 kg/m2. - Can understand, read and write English. - Has provided written, informed consent. - Surgeon has approved participation in the study
Minimum age
18 Years
Maximum age
65 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Chronic conditions requiring a specialised diet; food allergy or intolerance that may affect health or compliance with the study; vegetarian; individuals who cannot understand or follow the study diet; surgeon does not approve participation in the study; women who are pregnant or lactating; unwilling to be randomised to either diet group; pacemaker or other electronic implant.

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Type of endpoint(s)
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW

Funding & Sponsors
Funding source category [1] 4769 0
Self funded/Unfunded
Name [1] 4769 0
Address [1] 4769 0
Country [1] 4769 0
Primary sponsor type
University
Name
University of Newcastle
Address
University Drive, Callaghan NSW 2308
Country
Australia
Secondary sponsor category [1] 4306 0
None
Name [1] 4306 0
Address [1] 4306 0
Country [1] 4306 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 6817 0
The University of Newcastle Human Research Ethics Committee
Ethics committee address [1] 6817 0
University Drive, Callaghan NSW 2308
Ethics committee country [1] 6817 0
Australia
Date submitted for ethics approval [1] 6817 0
Approval date [1] 6817 0
14/11/2008
Ethics approval number [1] 6817 0

Summary
Brief summary
This study aims to investigate the usefulness of a high protein diet for obese individuals who have undergone gastric banding. It is a pseudo-randomised control trial comparing a high protein diet with usual dietetic care after surgery. The intervention period will be of six months duration with a further six months of follow-up. This study will help to inform best practice nutritional management for individuals who have had gastric banding.
Trial website
Trial related presentations / publications
Publication:

Dodsworth, A., H. Warren-Forward, and S. Baines, Feasibility of a protein-enriched diet after laparoscopic adjustable gastric banding: Results from a pilot intervention. e-SPEN Journal, 2012. 7(2): p. e57-e63.
Public notes

Contacts
Principal investigator
Name 29132 0
A/Prof Surinder Baines
Address 29132 0
School of Health Sciences Hunter Building, University of Newcastle University Drive, Callaghan NSW 2308
Country 29132 0
Australia
Phone 29132 0
+61 2 4921 5643
Fax 29132 0
Email 29132 0
surinder.baines@newcastle.edu.au
Contact person for public queries
Name 12289 0
A/Prof Surinder Baines
Address 12289 0
School of Health Sciences
Hunter Building, University of Newcastle
University Drive, Callaghan NSW 2308
Country 12289 0
Australia
Phone 12289 0
+61 2 4921 5643
Fax 12289 0
Email 12289 0
surinder.baines@newcastle.edu.au
Contact person for scientific queries
Name 3217 0
A/Prof Surinder Baines
Address 3217 0
School of Health Sciences
Hunter Building, University of Newcastle
University Drive, Callaghan NSW 2308
Country 3217 0
Australia
Phone 3217 0
+61 2 4921 5643
Fax 3217 0
Email 3217 0
surinder.baines@newcastle.edu.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary