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Trial registered on ANZCTR


Registration number
ACTRN12622000253707
Ethics application status
Approved
Date submitted
19/01/2022
Date registered
11/02/2022
Date last updated
23/06/2024
Date data sharing statement initially provided
11/02/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
Optimising daily carbohydrate intake for blood glucose management in people with type 2 diabetes; finding the sweet spot
Scientific title
Optimal carbohydrate dose to achieve glycaemic targets in people with Type 2 diabetes following a low carbohydrate diet; a proof a concept study
Secondary ID [1] 306030 0
nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Type 2 Diabetes 324663 0
Condition category
Condition code
Metabolic and Endocrine 322113 322113 0 0
Diabetes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This randomised crossover control trial will have a usual dietary intake period of 1-weeks followed by three 1-week intervention protocols assigned in random order; 50g per day total carbohydrate intake, 90g per day total carbohydrate intake and 130g per day total carbohydrate intake. Protein intake will remain constant and fat intake will be adjusted accordingly to ensure each arm is isoenergetic. There will be at least 1 week washout period between conditions.

Participants will receive a recipe book and a $600 grocery voucher. Sample meal plans will be provided and individual diets tailored during a 1-hour consultation with a dietitian (either face-to face or via telehealth) at the start of each intervention. A weekly scheduled e-mail/phone call check in will be available for participants, as well as unlimited email contact with the study dietitian as needed. Scales will be provided to assist participants accurately measure food and beverage quantity.

To control for weight-loss, the Mifflin equation will be used to estimate the daily energy requirement for each participant. Weight will be recorded at baseline and again following each 2-week intervention period. Caloric intake will be adjusted as needed prior to commencing the next intervention.

The app Easy Diet Diary will be used to self-report daily intake as an adherence measure, along with weekly check-ins with the dietitian
Intervention code [1] 322427 0
Lifestyle
Intervention code [2] 322428 0
Behaviour
Intervention code [3] 322733 0
Treatment: Other
Comparator / control treatment
The participants usual diet will be the control for each participant.
Control group
Active

Outcomes
Primary outcome [1] 329882 0
Glucose time in range (3.9-10 mmol/L) assessed using a continuous glucose monitor
Timepoint [1] 329882 0
Monitored continuously during each 2-week intervention period and control period
Secondary outcome [1] 404150 0
Changes in fasting blood glucose concentration assessed using a continuous glucose monitor
Timepoint [1] 404150 0
Monitored continuously during each 1-week intervention/control period
Secondary outcome [2] 404151 0
Changes in mean 24-h glucose area under the curve using a continuous glucose monitor
Timepoint [2] 404151 0
Monitored continuously during each 1-week intervention/control period
Secondary outcome [3] 404152 0
Changes in glucose time above range (> 10.0 mmol/L) using a continuous glucose monitor
Timepoint [3] 404152 0
Monitored continuously during each 1-week intervention/control period
Secondary outcome [4] 404153 0
Changes in incremental area under the glucose curve assessed using a continuous glucose monitor
Timepoint [4] 404153 0
Monitored continuously during each 1-week intervention/control period
Secondary outcome [5] 404156 0
pro-insulin: C-peptide ratio assessed using intravenous blood samples taken pre- and post-a mixed meal tolerance test
Timepoint [5] 404156 0
Monitored continuously during each 1-week intervention/control period
Secondary outcome [6] 404157 0
Changes in blood lipids including triglycerides and cholesterol
Timepoint [6] 404157 0
On day 1 and 7 of each 1-week intervention period
Secondary outcome [7] 404167 0
Disposition Index (DI) assessed using intravenous blood samples taken pre- and post-a mixed meal tolerance test
Timepoint [7] 404167 0
On day 1 and 7 of each 1-week intervention period
Secondary outcome [8] 404500 0
metabolic markers including fasting glucose, fasting insulin and apo-B assessed using intravenous blood samples
Timepoint [8] 404500 0
On day 1 and 7 of each 1-week intervention period
Secondary outcome [9] 404501 0
nutritional markers including prealbumin, IGF-1 and micronutrients (vitamins/minerals) assessed using intravenous blood samples taken pre- and post-a mixed meal tolerance test
Timepoint [9] 404501 0
On day 1 and 7 of each 1-week intervention period
Secondary outcome [10] 404502 0
inflammatory markers such as CRP and TNF-a assessed using intravenous blood samples taken pre- and post-a mixed meal tolerance test
Timepoint [10] 404502 0
On day 1 and 7 of each 1-week intervention period
Secondary outcome [11] 404503 0
Physical activity (including steps, light activity, standing and sedentary time) will be monitored using an ActivPAL inclinometer attached to the thigh using adhesive tape
Timepoint [11] 404503 0
On day 1 and 7 of each 1-week intervention period
Secondary outcome [12] 404504 0
Insulin sensitivity assessed using a venous blood sample,
Timepoint [12] 404504 0
On day 1 and 7 of each 1-week intervention period
Secondary outcome [13] 404505 0
Glucose variability assessed using a continuous glucose monitor
Timepoint [13] 404505 0
On day 1 and 7 of each 1-week intervention period
Secondary outcome [14] 404506 0
Dietary intake using the Easy Diet Diary app
Timepoint [14] 404506 0
On day 1 and 7 of each 1-week intervention period
Secondary outcome [15] 404507 0
Diet satisfaction assessed using the Diet Satisfaction 45 survey (Ello-Martin, 2006)
Timepoint [15] 404507 0
On day 1 and 7 of each 1-week intervention period
Secondary outcome [16] 404509 0
Weight assessed using electronic standing scales
Timepoint [16] 404509 0
On day 1 and 7 of each 1-week intervention period
Secondary outcome [17] 405629 0
Waist circumference assessed using a tape measure
Timepoint [17] 405629 0
On day 1 and 7 of each 1-week intervention period
Secondary outcome [18] 405636 0
Diet satisfaction assessed using audio-recorded, 30-minute, semi-structured qualitative interviews
Timepoint [18] 405636 0
At the conclusion of the study period (6 weeks from baseline minimum)
Secondary outcome [19] 405639 0
5-point Likert scale Theory of Planned Behaviour (TPB) survey
Timepoint [19] 405639 0
On day 1 and 7 of each 1-week intervention period

Eligibility
Key inclusion criteria
Aged between 30 and 70 years
Formal diagnosis of type 2 diabetes
Current HbA1c 6.5-9%
Stable medication and weight for previous 3 months
Minimum age
30 Years
Maximum age
70 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Non-English speakers
severe kidney or liver diseases
undergoing treatment for cancer
Previous bariatric surgery
Insulin or sulfonylureas
Pregnancy and breastfeeding
Food allergies or aversions that may prevent participation, to be evaluated on a case-by-case basis


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 concealed using sealed envelope
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation table generated by computer program
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis
Data will be analysed using a linear mixed model.

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,VIC

Funding & Sponsors
Funding source category [1] 310369 0
University
Name [1] 310369 0
University of Wollongong
Country [1] 310369 0
Australia
Primary sponsor type
University
Name
University of Wollongong
Address
Illawarra Health and Medical Institute, Building 32 University of Wollongong, Northfields Avenue Wollongong NSW 2500
Country
Australia
Secondary sponsor category [1] 311507 0
None
Name [1] 311507 0
not applicable
Address [1] 311507 0
not applicable
Country [1] 311507 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 310022 0
Joint University of Wollongong and Illawarra Shoalhaven Local Health District Health and Medical Human Research Ethics Committee
Ethics committee address [1] 310022 0
Ethics committee country [1] 310022 0
Australia
Date submitted for ethics approval [1] 310022 0
07/12/2021
Approval date [1] 310022 0
06/09/2022
Ethics approval number [1] 310022 0
2021/413

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 116214 0
Dr Monique Francois
Address 116214 0
University of Wollongong, Northfields Avenue Wollongong, NSW 2500
Country 116214 0
Australia
Phone 116214 0
+61 2 4221 5136
Fax 116214 0
Email 116214 0
Contact person for public queries
Name 116215 0
Katie Oetsch
Address 116215 0
University of Wollongong, Northfields Avenue Wollongong, NSW 2500
Country 116215 0
Australia
Phone 116215 0
+61 2 4221 5136
Fax 116215 0
Email 116215 0
Contact person for scientific queries
Name 116216 0
Katie Oetsch
Address 116216 0
University of Wollongong, Northfields Avenue Wollongong, NSW 2500
Country 116216 0
Australia
Phone 116216 0
+61 2 4221 5136
Fax 116216 0
Email 116216 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
14407Ethical approval    ethical approval is not yet available



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.