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Trial registered on ANZCTR


Registration number
ACTRN12615001272583
Ethics application status
Approved
Date submitted
18/11/2015
Date registered
23/11/2015
Date last updated
27/10/2016
Type of registration
Retrospectively registered

Titles & IDs
Public title
Comparing whey protein and guar gum preloads in type 2 diabetes
Scientific title
Differentiating the effects of whey protein and guar gum on postprandial glycaemia in type 2 diabetes.
Secondary ID [1] 287924 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
type 2 diabetes 296804 0
Condition category
Condition code
Metabolic and Endocrine 297033 297033 0 0
Diabetes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
On each study day, subjects will consume either (i) 20g whey protein concentrate, (ii) 5g guar gum, (iii) 20g whey protein concentrate + 5g guar gum each sweetened with 60mg sucralose or (iv) placebo (60mg sucralose alone) dissolved in 150 ml water (t = -20 min). 15 minutes later, subjects will eat a mixed standardized meal (65g powdered potato (Deb, Epping, NSW, Australia) reconstituted with 200ml water containing 20g glucose, 5g 3-O-methyl-glucose (3-OMG, a marker for glucose absorption), and one egg yolk containing 100 microL 13C-octanoic acid, within 5 min (t = -5-0 min). Breath samples will be collected immediately before, and every 5 minutes after, meal ingestion in the first hour and every 15 minutes for a further 3 hours for the measurement of gastric emptying . Venous blood sample (10 ml each) will be collected at t= -15, 0, 15, 30, 60, 90, 120, 180, 240 min for the measurements of blood glucose, serum 3-OMG, and plasma GLP-1, insulin and glucagon concentrations using established assays of our laboratory. At the same intervals used for blood sampling, appetite and gastrointestinal sensations will be assessed by means of validated 100 mm visual analogue scales. Each study day is separated by a 4 day wash-out period. Patients will be supervised during consumption of the preload and the mashed potato meal.
Intervention code [1] 293276 0
Treatment: Other
Comparator / control treatment
Cross-over design, patients will be receiving all four treatments, whey, guar, whey + guar, and placebo
Control group
Placebo

Outcomes
Primary outcome [1] 296630 0
The primary outcome of the study will be to compare the differences in the incremental area under the curve (iAUC) for blood glucose between the four treatments.
Timepoint [1] 296630 0
Venous blood sample will be collected at t= -15, 0, 15, 30, 60, 90, 120, 180, 240 min for the measurements of blood glucose. iAUC will be assessed.
Secondary outcome [1] 318953 0
The secondary outcomes are differences in the iAUC for serum 3-OMG
Timepoint [1] 318953 0
Venous blood sample (10 ml each) will be collected at t= -15, 0, 15, 30, 60, 90, 120, 180, 240 min for the measurements of serum 3-OMG, concentrations and iAUC will be calculated
Secondary outcome [2] 318992 0
The secondary outcomes are differences in the iAUC for plasma GLP-1
Timepoint [2] 318992 0
. Venous blood sample (10 ml each) will be collected at t= -15, 0, 15, 30, 60, 90, 120, 180, 240 min for the measurements of plasma GLP-1, and iAUC will be calculated
Secondary outcome [3] 318993 0
The secondary outcomes are differences in the iAUC for plasma insulin
Timepoint [3] 318993 0
. Venous blood sample (10 ml each) will be collected at t= -15, 0, 15, 30, 60, 90, 120, 180, 240 min for the measurements of plasma insulin concentrations and iAUC will be calculated
Secondary outcome [4] 318994 0
The secondary outcomes are differences in the iAUC for plasma glucagon.
Timepoint [4] 318994 0
. Venous blood sample (10 ml each) will be collected at t= -15, 0, 15, 30, 60, 90, 120, 180, 240 min for the measurements of glucagon concentrations and iAUC will be calculated.
Secondary outcome [5] 318995 0
Secondary composite outcomes are differences in appetite and gastrointestinal sensations as assessed by means of validated 100 mm visual analogue scales
Timepoint [5] 318995 0
Visual analogue scales will be assessed at t= -15, 0, 15, 30, 60, 90, 120, 180, 240 min

Eligibility
Key inclusion criteria
Male or female patients with a diagnosis of type 2 diabetes by WHO criteria (plasma glucose equal to 7.0 mmol/L fasting, or greater than 11.1 mmol/L two hours after a glucose challenge) or with a history of HbA1c greater than or equal to 6.5%, managed by diet or metformin
* Age 18 – 75 years
*Body mass index (BMI) 20- 40 kg/m2, and weight-stable
*HbA1c greater than equal 6.0% and less than or equal to 7.9% at the time of screening
*Haemoglobin above the lower limit of the normal range (i.e. greater than 135 g/L for men and 115 g/L for women), and ferritin above the lower limit of normal (i.e. greater than 10 mcg/L)
Minimum age
18 Years
Maximum age
75 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
*Requirement for antidiabetic medications other than metformin
*Significant gastrointestinal symptoms, or history of gastrointestinal disease including known gastroparesis, or surgery (other than appendicectomy or cholecystectomy)
*Intake of greater than 20 g alcohol on a daily basis, or cigarette smoking
*Volunteers who have donated blood in the preceding 3 months
*Current use of medications which are likely to affect gastrointestinal function or appetite (opiates, anticholinergics, levodopa, beta blockers, clonidine, nitrates, tricyclic antidepressants, selective serotonin re-uptake inhibitors, phosphodiesterase type 5 inhibitors, sumatriptan, metoclopramide, domperidone, cisapride, tegaserod, or erythromycin)
*Females of childbearing age who are pregnant, or lactating , or have inadequate contraception
*Vegetarians

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)
Allocation is not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomisation table created by computer software (i.e. computerised sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s


Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
The number of participants to be included in the study is based on power calculations performed by a professional biostatistician, Ms Kylie Lange. Based on our previous work it was determined that the inclusion of 21 participants would enable the detection of 0.6 mmol/l difference in mean blood glucose concentrations after the test meal between treatments. Significance was set at P = 0.008 to enable correction for multiple post-hoc testing and power of 80%. 25 volunteers with type 2 diabetes, to allow for dropouts, will be recruited

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)
SA
Recruitment hospital [1] 4674 0
The Royal Adelaide Hospital - Adelaide
Recruitment postcode(s) [1] 12255 0
5000 - Adelaide

Funding & Sponsors
Funding source category [1] 292404 0
Government body
Name [1] 292404 0
NHMRC funding
Country [1] 292404 0
Australia
Primary sponsor type
Government body
Name
Central Adelaide Local Health Network
Address
Level 4, Women's Health Centre
Royal Adelaide Hospital
North Terrace,
Adelaide 5000
South Australia
Country
Australia
Secondary sponsor category [1] 291087 0
None
Name [1] 291087 0
Address [1] 291087 0
Country [1] 291087 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 293871 0
Royal Adelaide Hospital Rsearch Ethics Committee
Ethics committee address [1] 293871 0
Royal Adelaide Hospital
North Terrace
Adelaide, 5000
South Australia
Ethics committee country [1] 293871 0
Australia
Date submitted for ethics approval [1] 293871 0
03/06/2015
Approval date [1] 293871 0
05/06/2015
Ethics approval number [1] 293871 0
HREC/15/RAH/225

Summary
Brief summary
We have previously demonstrated that consuming a mixture of whey protein and guar gum (a dietary fibre) before a meal (as a “preload”) can slow stomach emptying and improve blood sugar control after the meal in people with type 2 diabetes. In the current study, we want to compare the effects of the whey protein and guar gum given either separately or in combination in people with type 2 diabetes.
The current study is designed to evaluate the acute effects of whey protein and guar gum given in advance of the main meal either alone or in combination, on postprandial glycaemia (glucose levels after a meal), gastric emptying, glucose absorption, and the release of gut hormones and insulin in patients with type 2 diabetes.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 61614 0
Prof Chris Rayner
Address 61614 0
Discipline of Medicine
The University of Adelaide
Level 6 Eleanor Harrald Building
Frome Rd
Adelaide
SA
5000
Country 61614 0
Australia
Phone 61614 0
+61 8 82222916
Fax 61614 0
+61 82233870
Email 61614 0
Contact person for public queries
Name 61615 0
Prof Chris Rayner
Address 61615 0
Discipline of Medicine
The University of Adelaide
Level 6 Eleanor Harrald Building
Frome Rd
Adelaide
SA
5000
Country 61615 0
Australia
Phone 61615 0
+61 8 82222916
Fax 61615 0
+61 82233870
Email 61615 0
Contact person for scientific queries
Name 61616 0
Dr Linda Mignone
Address 61616 0
Discipline of Medicine
The University of Adelaide
Level 6 Eleanor Harrald Building
Frome Rd
Adelaide
SA
5000
Country 61616 0
Australia
Phone 61616 0
+61 8 82222915
Fax 61616 0
Email 61616 0

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What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

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