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Trial registered on ANZCTR


Registration number
ACTRN12618001344280
Ethics application status
Approved
Date submitted
6/08/2018
Date registered
9/08/2018
Date last updated
9/08/2018
Type of registration
Retrospectively registered

Titles & IDs
Public title
Does the Type of Dietary Protein affect Postprandial Glycaemia in Type 1 Diabetes?
Scientific title
Does the Type of Dietary Protein affect Postprandial Glycaemia in Type 1 Diabetes?
Secondary ID [1] 294499 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Type 1 Diabetes 307272 0
Condition category
Condition code
Metabolic and Endocrine 306390 306390 0 0
Diabetes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Relationship Between Type of Dietary Protein and Postprandial Glycaemia
A randomised, within-subject trial comparing capillary postprandial glycaemia for meals of varying types of protein over 5h with the same insulin dose for all meals (based on the insulin: carbohydrate (CHO) ratio) in 20 adults with T1D using insulin pump therapy.
Dietary Protein:
* 5 different types of protein (beef, chicken, egg, salmon and whey protein isolate) added to 45g CHO

Design Rationale:
This study will establish the relationship between type of protein and glycaemia for 5 different types of protein. Current literature in type 1 diabetes primarily relies on studies conducted using whey isolate, a particularly potent insulin secretagogue. Studies in other populations suggest that different sources of protein have differential effects. This study will therefore use commonly consumed protein sources to reflect realistic meals.

Test Meals & Insulin Doses
Insulin doses calculated using participants’ insulin: CHO ratio (standard clinical practice).
Test Meal A: 30g protein with 45g of CHO (beef with rice)
Test Meal B: 30g protein with 45g of CHO (chicken with rice)
Test Meal C: 30g protein with 45g of CHO (eggs with rice)
Test Meal D: 30g protein with 45g of CHO (salmon with rice)
Test Meal E: 30g protein with 45g of CHO (whey protein isolate with rice)

Wash out period: All test sessions must be completed on separate days but may be consecutive days.

Study Procedure:
Participants will be instructed to avoid alcohol and exercise for 24h prior to the session and not make any manual insulin adjustments (correction bolus or temporary basal rate) after midnight. Participants will be instructed to fast from midnight, with only water allowed. In the case of hypoglycaemia, participants will be instructed to treat their hypoglycaemia according to their usual clinical care and their test session will be rescheduled.
On the day of the test session, participants will arrive at the metabolic kitchen at the Charles Perkins Centre, University of Sydney between 7:00- 9:00am after an overnight fast. The fasting BGL must be between 4-10 mmol/L for the session to be commenced. If eligible, capillary blood samples will be taken 30, 15 and 0 minutes prior to the consumption of the test meal. The allocated insulin dose will be administered subcutaneously via an insulin pump by the CDE 15 minutes immediately prior to the consumption of the test meal. The test food will be served with 250mL of plain water and participants will be given 12 minutes to consume both the food and water and then no other food or drink will be provided for the remainder of the 5h test session (except water). Capillary blood samples will be collected at 15 min, 30 min, 45 min, 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h and 5h. If hypoglycaemia occurs (> 3.5 mmol/L), the test session will be terminated, the event recorded and the participant treated appropriately. Subjective satiety will be assessed using a 17-point likert scale.
Intervention code [1] 300796 0
Treatment: Other
Comparator / control treatment
This is a within subject trial and thus subjects serve as their own control. Blood glucose levels and insulin doses for different test meals will be compared within each individual.
Control group
Active

Outcomes
Primary outcome [1] 305403 0
Differences in 5hr iAUCglucose
Timepoint [1] 305403 0
The 5hr iAUCglucose will be calculated from capillary blood glucose level measurements taken at 15-30 minute intervals for 5 hrs (0, 15, 30, 45, 60, 90, 120, 150, 180, 210, 240, 270, 300 minutes).
Secondary outcome [1] 345067 0
Incidence of hypoglycaemia (< 3.5mmol/L)
Timepoint [1] 345067 0
The incidence of hypoglycaemia will be recorded from capillary blood glucose level measurements taken at 15-30 minute intervals for 5 hrs (0, 15, 30, 45, 60, 90, 120, 150, 180, 210, 240, 270, 300 minutes).
Secondary outcome [2] 345068 0
Mean postprandial blood glucose level
Timepoint [2] 345068 0
The mean postprandial blood glucose level will be calculated from capillary blood glucose level measurements taken at 15-30 minute intervals for 5 hrs (0, 15, 30, 45, 60, 90, 120, 150, 180, 210, 240, 270, 300 minutes).
Secondary outcome [3] 345069 0
Standard deviation around mean postprandial blood glucose level
Timepoint [3] 345069 0
The standard deviation around the mean postprandial blood glucose level will be calculated from capillary blood glucose level measurements taken at 15-30 minute intervals for 5 hrs (0, 15, 30, 45, 60, 90, 120, 150, 180, 210, 240, 270, 300 minutes).
Secondary outcome [4] 345070 0
Coefficient of Variation in blood glucose levels
Timepoint [4] 345070 0
The Coefficient of Variation will be calculated from capillary blood glucose level measurements taken at 15-30 minute intervals for 5 hrs (0, 15, 30, 45, 60, 90, 120, 150, 180, 210, 240, 270, 300 minutes).
Secondary outcome [5] 345071 0
J-Index of blood glucose levels
Timepoint [5] 345071 0
The J-Index will be calculated from capillary blood glucose level measurements taken at 15-30 minute intervals for 5 hrs (0, 15, 30, 45, 60, 90, 120, 150, 180, 210, 240, 270, 300 minutes).
Secondary outcome [6] 345072 0
Mean Amplitude of Glycaemic Excursion (MAGE)
Timepoint [6] 345072 0
The Mean Amplitude of Glycaemic Excursion (MAGE) will be calculated from capillary blood glucose level measurements taken at 15-30 minute intervals for 5 hrs (0, 15, 30, 45, 60, 90, 120, 150, 180, 210, 240, 270, 300 minutes).
Secondary outcome [7] 345073 0
Satiety
Timepoint [7] 345073 0
Measured using 17 point likert scale at 0, 15, 30, 45, 60, 90, 120, 150, 180, 210, 240, 270 and 300 minutes.

Eligibility
Key inclusion criteria
Aged 18-70y, T1D diagnosed for greater than or equal to 1 year, insulin pump therapy for greater than or equal to 3 months, HbA1c less than or equal to 8.5% (69 mmol/mol), reliably performing self-monitoring of blood glucose at least four times daily/or using continuous glucose monitoring and fluency in English.
Minimum age
18 Years
Maximum age
70 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Concurrent medical issues including coeliac disease and gastroparesis, food allergies, intolerances or eating disorders or use of other medication that may influence blood glucose levels, pregnancy or lactation.

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)
The order of the 5 meals will be randomised as each corresponding insulin dose will be determined by their existing clinically-prescribed insulin:carbohydrate ratio. The randomisation sequence will be generated using a computerised sequence generator.
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
17 participants will provide >80% power to detect an effect size of 20-25% in 5h iAUCglucose, allowing for a standard deviation (SD) of 27 mmol.hr/L. To allow for a 15% margin for dropouts, a total of 20 participants will be recruited.
If the session is stopped due to hypoglycaemia, the last recorded value will be carried forward. A general linear model with preprandial blood glucose level as a covariate will be used to analyse the parameters for the test conditions. The number of episodes of hypoglycaemia will be expressed as a proportion of all test sessions and compared by Chi-Square test and a Kaplan-Meier survival plot. Differences in coefficients will be considered statistically significant if p is < 0.05, and highly significant if p is < 0.01 (two-tailed).

Recruitment
Recruitment status
Recruiting
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
Recruitment hospital [1] 10559 0
Royal Prince Alfred Hospital - Camperdown
Recruitment hospital [2] 10560 0
Royal North Shore Hospital - St Leonards
Recruitment postcode(s) [1] 22278 0
2050 - Camperdown
Recruitment postcode(s) [2] 22279 0
2065 - St Leonards

Funding & Sponsors
Funding source category [1] 299123 0
Charities/Societies/Foundations
Name [1] 299123 0
ADEA Diabetes Research Foundation
Country [1] 299123 0
Australia
Primary sponsor type
University
Name
The University of Sydney
Address
Level 6, Jane Foss Russell Building G02,
The University of Sydney NSW 2006
Country
Australia
Secondary sponsor category [1] 298383 0
None
Name [1] 298383 0
Address [1] 298383 0
Country [1] 298383 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 300057 0
Sydney Local Health District Ethics Review Committee (RPAH Zone) [EC00113]
Ethics committee address [1] 300057 0
Research Ethics and Governance Office
Royal Prince Alfred Hospital
Missenden Rd
Camperdown NSW 2050
Ethics committee country [1] 300057 0
Australia
Date submitted for ethics approval [1] 300057 0
09/04/2018
Approval date [1] 300057 0
11/05/2018
Ethics approval number [1] 300057 0

Summary
Brief summary
Do you have Type 1 Diabetes and want to know how different types of protein affect your blood glucose levels?
The ‘iBolus: Protein’ Study is exploring how different types of protein impact blood glucose levels in adults with type 1 diabetes and using an insulin pump. You’ll be asked to have a blood test and attend 5 sessions at the University of Sydney to eat 5 different types of protein (beef, chicken, salmon, egg and protein shake) served with carbohydrate, take an insulin bolus and monitor your BGL for 5.5hr.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 82418 0
Dr Kirstine Bell
Address 82418 0
Charles Perkins Centre
The University of Sydney NSW 2006
Country 82418 0
Australia
Phone 82418 0
+61 2 8627 42 50
Fax 82418 0
Email 82418 0
Contact person for public queries
Name 82419 0
Dr Kirstine Bell
Address 82419 0
Charles Perkins Centre
The University of Sydney NSW 2006
Country 82419 0
Australia
Phone 82419 0
+61 2 8627 42 50
Fax 82419 0
Email 82419 0
Contact person for scientific queries
Name 82420 0
Dr Kirstine Bell
Address 82420 0
Charles Perkins Centre
The University of Sydney NSW 2006
Country 82420 0
Australia
Phone 82420 0
+61 2 8627 42 50
Fax 82420 0
Email 82420 0

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No Supporting Document Provided



Results publications and other study-related documents

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