Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12613000013763
Ethics application status
Approved
Date submitted
19/12/2012
Date registered
7/01/2013
Date last updated
7/01/2013
Type of registration
Retrospectively registered

Titles & IDs
Public title
Influence of glycaemic index on day-long glycaemia in type 2 diabetics
Scientific title
Effect of food selection using the glycaemic index on day-long glycaemia measured with a continuous glucose monitor in people with type 2 diabetes
Secondary ID [1] 281699 0
None
Universal Trial Number (UTN)
U1111-1137-9909
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Type 2 diabetes 287987 0
Condition category
Condition code
Diet and Nutrition 288370 288370 0 0
Other diet and nutrition disorders
Metabolic and Endocrine 288409 288409 0 0
Diabetes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
People with type 2 diabetes will be given food for four days to cover breakfast, lunch and dinner. For two of the days they will eat low glycaemic index foods, for the other two days high glycaemic index foods. The order of the low and high glycaemic index periods will be randomized to each person. The low glycaemic index foods will be Kelloggs Special K breakfast cereal, Vogels Soy and Linseed bread for lunch, and Watties Chicken Penne pasta frozen meal for dinner. The corresponding food on the high glycaemic index days will be Sanitarium Weetbix, Natures Fresh white bread and Watties rice and chicken frozen meal. The foods were chosen to have the same available carbohydrate content. ie: the frozen rice and pasta meals contained equivalent carbohydrate; the slices of Vogels and Natures Fresh bread contained equivalent carbohydrate; and the amount od Special K consumed was matched for carbohydrate content with the number of Weetbix biscuits. In recognition that different people eat different amounts of food, each person was free to choose the amount (ie: 2 slices or 4 slices of bread at lunch). However, if a person ate four white slices during the high glycaemic index phase then they were told to eat four Vogels slices during the low glycaemic index phase. The same principles applied to breakfast and dinner meals (people will be supplied with two of each frozen meal per day with a choice to consume one or both, if one meal is sufficient then one pasta meal will be consumed each of the low glycaemic index days and one rice meal on each of the high glycaemic index days). Bread fillings and any additional snack foods will be weighed and recorded. During this period, interstitial glucose concentrations will be measured with a continuous glucose monitoring device. The low and high glycaemic index periods will be consecutive with no washout.
Intervention code [1] 286235 0
Lifestyle
Comparator / control treatment
This is a randomized crossover study in which glycaemic responses will be compared in each person between two days of eating low glycaemic index foods compared with two days of eating high glycaemic index foods. Both periods will hold equal weight in this comparison.
Control group
Active

Outcomes
Primary outcome [1] 288543 0
Postprandial and day-long glycaemia as assessed using a continuous glucose monitor
Timepoint [1] 288543 0
Interstitial glucose measurements taken every 5 minutes for a period of 96 hours. The start time of the monitoring will be at the commencement of the first meal and the end time will occur 3 hours after starting the last meal. ie: monitoring occurs continuously during the entire four day period.
Secondary outcome [1] 300428 0
Reproducibility of repeated day-long glycaemia. Incremental area under the blood glucose curve (iAUC) after each meal and for each day (24 hour period) will be calculated from the continuous monitoring data for each person using the trapezoidal method.
Timepoint [1] 300428 0
Comparison between two days readings. The group average of the two days low glycaemic index iAUC will be compared with the average iAUC during the high glycaemic index period using repeated measures ANOVA.

Eligibility
Key inclusion criteria
Type 2 diabetes

Non insulin users
Minimum age
18 Years
Maximum age
75 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Use of insulin
Diagnosis of cardiovascular disease, cancer, or diseases of the gastrointestinal system

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)
Volunteers will respond to advertisement and be given an information sheet in which the aims and procedures of the study are described. Allocation to treatment order will be by coin toss so that neither the participant nor the investigator is aware of treatment order at enrolment. ie: the person who determined if a subject was eligible for inclusion in the trial was unaware as to whether the person would start on the low or high glycaemic index diet before swapping over to the alternative.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
There was no allocation concealment. The starting diet was determined by coin toss.
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Data will assessed for normal distribution and transformed if necessary.
ANOVA will be used to test for differences in glycaemia between treatments.
Reliability of the measure will be assessd using intraclass correlation coefficient

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
16/07/2012
Actual
16/07/2012
Date of last participant enrolment
Anticipated
18/02/2013
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
22
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
Recruitment outside Australia
Country [1] 4764 0
New Zealand
State/province [1] 4764 0
Otago

Funding & Sponsors
Funding source category [1] 286488 0
University
Name [1] 286488 0
University of Otago
Country [1] 286488 0
New Zealand
Primary sponsor type
University
Name
University of Otago
Address
Department of Human Nutrition
PO Box 56
Dunedin
9054
Country
New Zealand
Secondary sponsor category [1] 285278 0
None
Name [1] 285278 0
Address [1] 285278 0
Country [1] 285278 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 288564 0
University of Otago Human Ethics Committee
Ethics committee address [1] 288564 0
PO Box 56
Dunedin
9054
Ethics committee country [1] 288564 0
New Zealand
Date submitted for ethics approval [1] 288564 0
Approval date [1] 288564 0
29/06/2012
Ethics approval number [1] 288564 0
12/164

Summary
Brief summary
It is important for people with type 2 diabetes to keep blood glucose concentrations under control. Diabetes NZ recommends choosing foods based on the Glycaemic Index A high glycaemic index food (eg: potato) is characterized as producing a fast and high blood glucose response followed by a rapid decline, whereas a low glycaemic index food (eg: pasta) induces a more gradual ascent and decline. These patterns relate to individual foods tested under laboratory conditions. Whether the same patterns of response occur in an everyday setting is unknown.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 36698 0
Dr Bernard Venn
Address 36698 0
Department of Human Nutrition
PO Box 56
Dunedin
9054
Country 36698 0
New Zealand
Phone 36698 0
+6434795068
Fax 36698 0
Email 36698 0
bernard.venn@otago.ac.nz
Contact person for public queries
Name 36699 0
Dr Bernard Venn
Address 36699 0
Department of Human Nutrition
PO Box 56
Dunedin
9054
Country 36699 0
New Zealand
Phone 36699 0
+6434795068
Fax 36699 0
Email 36699 0
bernard.venn@otago.ac.nz
Contact person for scientific queries
Name 36700 0
Dr Bernard Venn
Address 36700 0
Department of Human Nutrition
PO Box 56
Dunedin
9054
Country 36700 0
New Zealand
Phone 36700 0
+6434795068
Fax 36700 0
Email 36700 0
bernard.venn@otago.ac.nz

No information has been provided regarding IPD availability


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

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