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Trial registered on ANZCTR


Registration number
ACTRN12617001363370p
Ethics application status
Not yet submitted
Date submitted
14/09/2017
Date registered
27/09/2017
Date last updated
27/09/2017
Type of registration
Prospectively registered

Titles & IDs
Public title
LUCI1D Study: Lowering Carbohydrate Intake in Adults with Type 1 Diabetes
Scientific title
LUCI1D Study: Effect of lowering Carbohydrate Intake on HbA1c and insulin dose requirement in Adults with Type 1 Diabetes
Secondary ID [1] 292884 0
Nil known
Universal Trial Number (UTN)
U1111-1202-1675
Trial acronym
LUCI1D Study - Lowering Carbohydrate Intake in adults with type 1 Diabetes
Linked study record
Nil

Health condition
Health condition(s) or problem(s) studied:
Type 1 Diabetes Mellitus 304730 0
Condition category
Condition code
Metabolic and Endocrine 304046 304046 0 0
Diabetes

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Intervention: Participants will receive dietary advice to actively lower average daily carbohydrate intake to less than 100g. Education will be provided by a dietitian with at least 5-years' clinical experience. The education session will be a 1-hour one-on-one session conducted in the hospital diabetes clinic, followed by two 30-minute follow-up sessions at 1 and 2 weeks post-randomization. The content will be based on the recommendations contained in the CSIRO Low Carbohydrate Diet, but adapted for use in the study by the research team. Personalized meal plans will be developed by the dietitian with each participant, including 4-6 meal options for breakfast, lunch and dinner along with options for snacks. A matching program of education regarding expected insulin dose reductions will be delivered by the Endocrinologist conducting the study. This will be provided in a 20-minute session following the dietitian education, and supported by personalized insulin dose recommendations in written format. Written information regarding lower carbohydrate diets, recipe options and guidelines for insulin dose adjustments will be provided in written and electronic format.
Close follow-up will be provided to ensure safety and support to participants, through weekly phone or email contact for the first 4 weeks, and then fortnightly. The duration of the intervention will be 3 months (post randomization).
Intervention code [1] 299123 0
Treatment: Other
Comparator / control treatment
Comparator / control treatment:
The control group is a wait-list control, where participants will be advised to continue their usual diet so that their minimum daily average intake of carbohydrate is 150g for a period of 3 months following randomization. Follow-up contact will be made monthly by email or phone by the Chief Investigator or research Nurse during the 3 months.

This group receives the intervention (lower carbohydrate diet recommendations) after 3 months.

These participants will follow standard practice of carbohydrate counting and dose adjustments of Apidra according to prescribed carbohydrate ratios and correction factors. Education regarding carbohydrate counting, matching doses of Apidra for dietary carbohydrate will be provided in by the Dietitian and the Endocrinologist. This will be provided in the Run-in Phase and updated at the beginning of the 3 months for this group. This 1-hour session will be provided in the hospital diabetes clinic.
Control group
Active

Outcomes
Primary outcome [1] 303376 0
Mean change in HbA1c, as measured by serum assay at 3 months
Timepoint [1] 303376 0
Primary endpoints will be measured at 3 months, and compared with the baseline dataset. The control group then is exposed to the intervention for 3 months. Data will be recollected at the 6-month time point for both groups where the participants in the "control" group and "intervention" group will have been exposed to the intervention for 3-months and 6-months respectively.
Primary outcome [2] 303377 0
Mean change in insulin dose requirement, assessed at 3 months. The information about insulin dose requirement will be collected as self-reported insulin doses during participant interview.
Timepoint [2] 303377 0
Primary endpoints will be measured at 3 months after randomization.
The control group then is exposed to the intervention for 3 months. Data will be recollected at the 6-month time point (following randomization) for both groups where the participants in the "control" group and "intervention" group will have been exposed to the intervention for 3-months and 6-months respectively.
Secondary outcome [1] 338769 0
Change in parameters of glycaemic variability as calculated from continuous glucose monitoring data.
These calculations include standard deviation, Mean Amplitude of Glycaemic Excursion (MAGE), and J-index as validated methods of assessing glycaemic variability from CGM data.
Timepoint [1] 338769 0
Secondary endpoints will be measured at 3 months after randomization.
The control group then is exposed to the intervention for 3 months. Data will be recollected at the 6-month time point (following randomization) for both groups where the participants in the "control" group and "intervention" group will have been exposed to the intervention for 3-months and 6-months respectively.
Secondary outcome [2] 338770 0
Change in the composition of colonic microbiota. Stool specimens will be analysed using 16S ribosomal RNA quantitative PCR methods to determine the predominant bacterial species.
Timepoint [2] 338770 0
Secondary endpoints will be measured at 3 months after randomization.
The control group then is exposed to the intervention for 3 months. Data will be recollected at the 6-month time point (following randomization) for both groups where the participants in the "control" group and "intervention" group will have been exposed to the intervention for 3-months and 6-months respectively
Secondary outcome [3] 338771 0
Change in level of diabetes treatment satisfaction, using the Diabetes Treatment Satisfaction Questionnaire (DTSQ).
At baseline, the DTSQs will be used to assess baseline level of satisfaction
At 3 months, the matching questionnaire (DTSQc) will be used to assess for change in level of treatment satisfaction.
Timepoint [3] 338771 0
At 3 months after randomization.
Secondary outcome [4] 338772 0
Change in mean visceral adipose tissue, as measured by DEXA scan.
Timepoint [4] 338772 0
Secondary endpoints will be measured at 3 months after randomization.
The control group then is exposed to the intervention for 3 months. Data will be recollected at the 6-month time point (following randomization) for both groups where the participants in the "control" group and "intervention" group will have been exposed to the intervention for 3-months and 6-months respectively
Secondary outcome [5] 338996 0
Change in fasting lipid profile, Serum measures of total cholesterol, triglycerides and LDL cholesterol will be measured 3 months after randomization
Timepoint [5] 338996 0
Secondary endpoints will be measured at 3 months after randomization.
The control group then is exposed to the intervention for 3 months. Data will be recollected at the 6-month time point (following randomization) for both groups where the participants in the "control" group and "intervention" group will have been exposed to the intervention for 3-months and 6-months respectively
Secondary outcome [6] 338997 0
Change in serum levels of inflammatory mediators, including high sensitivity CRP and free fatty acids
Timepoint [6] 338997 0
Secondary endpoints will be measured at 3 months after randomization.
The control group then is exposed to the intervention for 3 months. Data will be recollected at the 6-month time point (following randomization) for both groups where the participants in the "control" group and "intervention" group will have been exposed to the intervention for 3-months and 6-months respectively

Eligibility
Key inclusion criteria
Age 18 - 80
Confirmed diagnosis of Type 1 Diabetes
Basal bolus insulin regimen

Minimum age
18 Years
Maximum age
80 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Pregnant or breastfeeding
Recognised diagnosis of eating disorder
Malabsorption syndrome eg. coeliac disease
Stage 3-5 Chronic Kidney Disease
Unwilling to attend clinic

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)
Yes - sealed opaque envelopes will be used for randomization
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software (i.e. computerised sequence generation
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?


The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Other
Other design features
The study includes a wait-list control group whereby the control group waits 3 months before receiving the intervention.
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
Power calculations are based on 80% power to detect an absolute reduction in HbA1c of 0.5% at a significance level of 0.05 on a two-tailed test.
The data obtained will be analysed using descriptive statistics.
A multivariate (linear/ logistic / negative binomial) regression model will be used to identify if there are significant differences in clinical outcomes

Recruitment
Recruitment status
Not yet 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)
QLD
Recruitment hospital [1] 9026 0
Toowoomba Hospital - Toowoomba
Recruitment postcode(s) [1] 17502 0
4350 - Toowoomba

Funding & Sponsors
Funding source category [1] 297513 0
Charities/Societies/Foundations
Name [1] 297513 0
Toowoomba Hospital Foundation
Address [1] 297513 0
Joyce Street, Toowoomba QLD 4350
Country [1] 297513 0
Australia
Primary sponsor type
University
Name
University of Queensland
Address
Faculty of Medicine
University of Queensland
288 Herston Road
Herston, QLD 4006
Country
Australia
Secondary sponsor category [1] 296518 0
Hospital
Name [1] 296518 0
Toowoomba Hospital
Address [1] 296518 0
Department of Medicine
Toowoomba Hospital
Pechey Street
Toowoomba QLD 4350
Country [1] 296518 0
Australia

Ethics approval
Ethics application status
Not yet submitted
Ethics committee name [1] 298612 0
Darling Downs Hospital and Health Service HREC
Ethics committee address [1] 298612 0
DDHHS HREC Coordinator
Level 5 Surgical Block
Toowoomba Hospital
PMB 2
Toowoomba QLD 4350
Ethics committee country [1] 298612 0
Australia
Date submitted for ethics approval [1] 298612 0
28/09/2017
Approval date [1] 298612 0
Ethics approval number [1] 298612 0

Summary
Brief summary
The increasing popularity of low carbohydrate diets in the community has meant that people with Type 1 Diabetes are adopting these diets, with the expectation of improved glucose control and weight loss.
Where there is very limited research to guide this practice in people with Type 1 Diabetes, this project aims to assess whether lowering dietary carbohydrate improves glucose control and clinical outcomes for adults with Type 1 Diabetes Mellitus.
This study is a randomized controlled study of adults with Type 1 Diabetes, that aims to compare the effect of a lower carbohydrate diet (average intake of less than 100g per day) with standard dietary recommendations (more than 150g per day) on glucose control, insulin doses, rates of hypoglycaemia, perceived quality of life and treatment satisfaction.
We seek to explore potential mechanisms for changes in glucose control, focusing on the impact of dietary changes on the gut microbiome, intestinal epithelial permeability, body composition and inflammatory mediators.
We hypothesise that intentional lowering of dietary carbohydrate will be associated with reduced dose requirement of insulin, reduced glucose variability and rates of hypoglycaemia, improved measures of perceived quality of life and alteration of gut microbiome. We expect to see a difference in the groups at 3 months, and will extend the intervention to 6 months to assess whether this dietary change is sustainable for people with Type 1 Diabetes.
Participants will receive detailed education regarding carbohydrate counting, recommendations for meal plans that contain a reduced carbohydrate content and advice regarding insulin dose adjustments according to changing glucose levels. Close follow-up will be maintained by diabetes health care professionals.
Data will be collected at baseline, 3 months and 6 months, to investigate traditional clinical outcomes - HbA1c, lipid profile, urinary protein and glucose variability as well as perceived quality of life. The effect of the dietary change will also be assessed on the intestinal microbiome, epithelial permeability and body composition.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 77650 0
Dr Sheila Cook
Address 77650 0
Department of Medicine
Level 6, Emma Webb Building
Toowoomba Hospital
PMB 2 Toowoomba QLD 4350
Country 77650 0
Australia
Phone 77650 0
+61 7 4616 6000
Fax 77650 0
+61 7 4616 6793
Email 77650 0
s.cook1@uq.edu.au
Contact person for public queries
Name 77651 0
Dr Sheila Cook
Address 77651 0
Department of Medicine
Level 6 Emma Webb Building
Toowoomba Hospital
Pechey Street
Toowoomba QLD 4350
Country 77651 0
Australia
Phone 77651 0
+61 7 4616 6000
Fax 77651 0
+61 7 4616 6793
Email 77651 0
s.cook1@uq.edu.au
Contact person for scientific queries
Name 77652 0
Dr Sheila Cook
Address 77652 0
Department of Medicine
Level 6 Emma Webb Building
Toowoomba Hospital
Pechey Street
Toowoomba QLD 4350
Country 77652 0
Australia
Phone 77652 0
+61 7 4616 6000
Fax 77652 0
+61 7 4616 6793
Email 77652 0
s.cook1@uq.edu.au

No data has been provided for results reporting
Summary results
Not applicable