Condition category
Nutritional, Metabolic, Endocrine
Date applied
13/01/2010
Date assigned
18/01/2010
Last edited
27/09/2016
Prospective/Retrospective
Prospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
Type 2 diabetes is a condition where the pancreas doesn't produce enough insulin or the body's cells don't react to insulin, causing the blood sugar level to become too high. The aim of this study is to determine how the type of foods in a diet can affect blood sugar control and heart and blood vessel health in people with type 2 diabetes. The glycaemic index is a scale that ranks carbohydrate foods by how much they raise blood sugar levels compared to a standard food. In this study a low glycaemic index diet is compared to a standard healthy high fibre diet.

Who can participate?
Patients aged over 21 with type 2 diabetes

What does the study involve?
Participants are randomly allocated to be given dietary advice on either a low glycaemic index diet or a high fibre diet. They are required to keep a 7-day food record every 3 months throughout the 3-year study. Blood tests and body measurements are carried out every 3 months. Participants undergo MRI and ultrasound scans to look at the walls of the carotid arteries, the largest blood vessels in the neck. Retinal photographs are taken to look at the arteries in the eye. The MRI, ultrasound, and eye tests are done at the beginning of the study, after 1 year, and at the end (3 years).

What are the possible benefits and risks of participating?
This study assesses whether this dietary help can improve risk factors for heart disease. This may not benefit participants, but may improve how patients are treated in the future. There are small risks with having blood drawn and if a contrast dye is used for the MRI, which are explained in the consent form.

Where is the study run from?
1. St Michael's Hospital (Canada)
2. University of Toronto (Canada)

When is the study starting and how long is it expected to run for?
February 2010 to August 2016

Who is funding the study?
Canadian Institutes of Health Research (Canada)

Who is the main contact?
Dr David Jenkins

Trial website

Contact information

Type

Scientific

Primary contact

Dr David Jenkins

ORCID ID

Contact details

61 Queen St. East
6th Floor
Toronto
M5C 2T2
Canada

Additional identifiers

EudraCT number

ClinicalTrials.gov number

NCT01063374

Protocol/serial number

09-193; MCT-98825

Study information

Scientific title

Low glycaemic index diets to improve glycaemic control and cardiovascular disease in type 2 diabetics: a randomised controlled trial

Acronym

Study hypothesis

A low glycaemic index diet will improve glycaemic control and plaque build-up in type 2 diabetics, compared to a high fibre diet.

Ethics approval

St Michael's Hospital Research Ethics Board, 16/12/2009, ref: REB09-093

Study design

Randomised controlled trial

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Hospitals

Trial type

Treatment

Patient information sheet

Not available in web format, please use the contact details to request a patient information sheet

Condition

Type 2 diabetes

Intervention

Participants will be randomly assigned to receive dietary counselling for either a low glycaemic index diet, or a high cereal fibre diet for a three year period. Subjects will be followed for 3 years after starting the study.

Intervention type

Other

Phase

Not Applicable

Drug names

Primary outcome measures

Current primary outcome measures as of 15/09/2016:
Plaque volume, assessed by MRI at 1 and 3 years

Previous primary outcome measures:
1. Carotid intima media thickness
2. HbA1c
3. Plasma glucose and lipids
Magnetic resonance imaging (MRI) of intima media will take place at 0, 1 year, and 3 years. Blood tests and clinic visits will take place every 3 months during the 3 years.

Secondary outcome measures

Current secondary outcome measures as of 15/09/2016:
1. Intima media thickness, assessed by 3D carotid ultrasound at 1 and 3 years
2. Plaque morphology measured at 1 and 3 years
3. HbA1c measured every 3 months for 3 years
4. Serum lipids measured every 3 months for 3 years
5. Blood pressure measured every 3 months for 3 years
6. Serum fasting glucose measured every 3 months for 3 years
7. Creatinine, urea, and C-peptides in 24 hour urine collection measured at 1 and 3 years
8. Anthropometric measures (weight, waist and hip circumference), measured every 3 months for 3 years
9. Retinal photography measured at 1 and 3 years

Previous secondary outcome measures:
1. Anthropometric measures
2. Blood and urine tests
Blood tests and clinic visits will take place every 3 months during the 3 years.

Overall trial start date

01/02/2010

Overall trial end date

01/08/2016

Reason abandoned

Eligibility

Participant inclusion criteria

Current inclusion criteria as of 15/09/2016:
1. Type 2 diabetes diagnosed for greater than 6 months
2. Men and women aged over 21 years
3. Stable dose of hypoglycaemic medication
4. HbA1c between 6.5 and 8.0 at screening, and pre-study visit
5. Stable weight
6. Family physician and valid health card
7. Stable dose of lipid medication, if prescribed
8. Stable dose of blood pressure medication, if prescribed
9. Ability to keep written food records, use digital food scale

Previous inclusion criteria:
1. Type 2 diabetes dignosed for greater than 6 months
2. Men and post-menopausal women, aged over 21 years
3. Stable dose of hypoglycaemic medication
4. HbA1c between 6.5 and 8%
5. Stable weight
6. Family physician and valid health card
7. Stable dose of lipid medication, if prescribed
8. Stable dose of blood pressure medication, if prescribed
9. Ability to keep written food records, use digital food scale

Participant type

Patient

Age group

Adult

Gender

Both

Target number of participants

160

Participant exclusion criteria

1. Insulin, steroids, or warfarin
2. Gastrointestinal disease
3. Major cardiovascular event in past 6 months
4. Major surgery in past 6 months
5. Liver disease, hepatitis B or C
6. Renal failure
7. Major debilitating disorder
8. Serum triglycerides greater than 6 mmol/L
9. History of cancer (except non-melanoma skin cancer)
10. Pre-menopausal women
11. Food allergies to study foods
12. Blood pressure above 145/90 mmHg
13. Acute or chronic infections
14. Chronic inflammatory diseases
15. Inability to undergo magnetic resonance imaging (MRI)
16. Any other condition which make one unsuitable for the study

Recruitment start date

01/02/2010

Recruitment end date

01/05/2013

Locations

Countries of recruitment

Canada

Trial participating centre

St Michael's Hospital
Toronto
M5C 2T2
Canada

Sponsor information

Organisation

St Michael's Hospital (Canada)

Sponsor details

30 Bond St
Toronto
M5B 1W8
Canada

Sponsor type

Hospital/treatment centre

Website

http://www.stmichaelshospital.com

Organisation

University of Toronto (Canada)

Sponsor details

Department of Nutritional Sciences
Faculty of Medicine
150 College St
Room 340
Toronto
M5S 3E2
Canada

Sponsor type

University/education

Website

www.utoronto.ca

Funders

Funder type

Research organisation

Funder name

Canadian Institutes of Health Research (ref: MCT-98825)

Alternative name(s)

Instituts de Recherche en Santé du Canada, CIHR

Funding Body Type

government organisation

Funding Body Subtype

Federal/National Government

Location

Canada

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes

27/09/2016: Plain English summary added. 15/09/2016: the overall trial end date was changed from 01/09/2015 to 01/08/2016.