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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/show/NCT02112721




Registration number
NCT02112721
Ethics application status
Date submitted
10/04/2014
Date registered
14/04/2014
Date last updated
8/12/2016

Titles & IDs
Public title
Can Vitamin D Supplementation Prevent Type 2 Diabetes?
Scientific title
Can Vitamin D Supplementation Prevent Type 2 Diabetes by Improving Insulin Sensitivity and Secretion in Overweight Humans?
Secondary ID [1] 0 0
1047897
Universal Trial Number (UTN)
Trial acronym
Linked study record

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

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Other interventions - Vitamin D
Other interventions - Placebo

Experimental: Vitamin D Group - Each participant will be given an initial stat dose of 2500 µg (100,000 IU) of Ostelin (Reckitt Benckiser). Thereafter, participants will take 100 µg/day (4,000 IU, 4 tablets) Ostelin daily for a period of 16 weeks.

Placebo Comparator: Placebo group - Each participant will be given an equivalent number of placebo tablets


Other interventions: Vitamin D


Other interventions: Placebo


Intervention code [1] 0 0
Other interventions
Comparator / control treatment
Control group

Outcomes
Primary outcome [1] 0 0
Initial Insulin Sensitivity Measure using Euglycaemic glucose clamp - The clamp will be used to measure insulin sensitivity. The clamp is initiated by an intravenous bolus injection of insulin (9milliUnit/kg). Insulin is then constantly infused at a rate of 40 milliUnit.m-2.min-1 for 120 min into an arm vein, whilst glucose is variably infused to maintain euglycaemia. Plasma glucose values will be monitored every 5 minutes during the clamp and the variable infusion rate of glucose is adjusted to maintain blood glucose at a constant value of 5mmol/L.
Timepoint [1] 0 0
Week 1
Primary outcome [2] 0 0
Follow up Insulin Sensitivity Measure using Euglycaemic glucose clamp - The clamp will be used to measure insulin sensitivity. The clamp is initiated by an intravenous bolus injection of insulin (9milliUnit/kg). Insulin is then constantly infused at a rate of 40 milliUnit.m-2.min-1 for 120 min into an arm vein, whilst glucose is variably infused to maintain euglycaemia. Plasma glucose values will be monitored every 5 minutes during the clamp and the variable infusion rate of glucose is adjusted to maintain blood glucose at a constant value of 5mmol/L.
Timepoint [2] 0 0
Week 17
Secondary outcome [1] 0 0
Initial measurement of inflammatory markers - Plasma inflammatory markers (interleukin 1ß, 6, 8 and 10, TNFa, macrophage migration inhibitory factor, monocyte chemotactic protein-1) will be measured by quantitative sandwich enzyme immunoassays (R & D Systems Inc, USA) (interassay Coefficients of Variation: 7.2%, 10.2%, 5.8%, respectively). Plasma C- reactive protein (hsCRP) via a high sensitivity assay (BN-II nephelometer; Dade Behring Diagnostics, NSW).
Timepoint [1] 0 0
Week 1
Secondary outcome [2] 0 0
Follow Up Measurement of inflammatory markers - Plasma inflammatory markers (interleukin 1ß, 6, 8 and 10, TNFa, macrophage migration inhibitory factor, monocyte chemotactic protein-1) will be measured by quantitative sandwich enzyme immunoassays (R & D Systems Inc, USA) (interassay Coefficients of Variation: 7.2%, 10.2%, 5.8%, respectively). Plasma C- reactive protein (hsCRP) via a high sensitivity assay (BN-II nephelometer; Dade Behring Diagnostics, NSW).
Timepoint [2] 0 0
Week 17
Secondary outcome [3] 0 0
Initial Measure of Adiposity (DEXA) - body composition by dual energy x-ray absorptiometry (DEXA), which is a non-invasive assessment of soft tissue composition by region with a precision of 4-5%; central adiposity assessed in duplicate using a constant-tension tape for taking waist, and hip circumference. Bioimpedance measurement will be also collected for validation purposes.
Timepoint [3] 0 0
Week 1
Secondary outcome [4] 0 0
Follow Up Measure of Adiposity (DEXA) - body composition by dual energy x-ray absorptiometry (DEXA), which is a non-invasive assessment of soft tissue composition by region with a precision of 4-5%; central adiposity assessed in duplicate using a constant-tension tape for taking waist, and hip circumference. Bioimpedance measurement will be also collected for validation purposes.
Timepoint [4] 0 0
Week 17
Secondary outcome [5] 0 0
Initial Oral Glucose Tolerance Test - OGTT - After a 10-12 h overnight fast, participants will ingest 75g of glucose over 2 mins. Blood samples will be drawn at 0, 30, 60, 90 and 120 min for plasma glucose and insulin concentrations. We will evaluate the area under the curve.
Timepoint [5] 0 0
Week 1
Secondary outcome [6] 0 0
Follow Up Oral Glucose Tolerance Test -OGTT - After a 10-12 h overnight fast, participants will ingest 75g of glucose over 2 mins. Blood samples will be drawn at 0, 30, 60, 90 and 120 min for plasma glucose and insulin concentrations. We will evaluate the area under the curve.
Timepoint [6] 0 0
Week 17
Secondary outcome [7] 0 0
Initial Acute Insulin Secretory Response - Intravenous Glucose Tolerance Test - This will be measured in response to 25g intravenous glucose and calculated as the average incremental plasma insulin level from the third to the fifth minute after the glucose bolus.
Timepoint [7] 0 0
Week 1
Secondary outcome [8] 0 0
Follow up Acute Insulin Secretory Response- Intravenous Glucose Tolerance Test - This will be measured in response to 25g intravenous glucose and calculated as the average incremental plasma insulin level from the third to the fifth minute after the glucose bolus.
Timepoint [8] 0 0
Week 17

Eligibility
Key inclusion criteria
- Age >18 or <60 years,

- 25(OH)D < 50 nmol/L

- Weight change < 5 kg in last 12 months

- BMI >25kg/m2 but weight <159kg due to DEXA scan restrictions

- Non-diabetic, no allergy, non-smoker, no high alcohol use

- No current intake of medications including vitamin supplements

- No kidney, cardiovascular, haematological, respiratory, gastrointestinal, endocrine or
central nervous system disease, as well as no psychiatric disorders, no active cancer
within the last five years; no presence of acute inflammation (by history, physical or
laboratory examination)

- Not menopausal, pregnanct or lactating
Minimum age
18 Years
Maximum age
60 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
- Age <18 or > 60 years

- 25(OH)D > 50 nmol/L

- Weight change > 5 kg in last 12 months

- Diabetes (diagnosed or oral glucose tolerance test (OGTT), hypercalcaemia, allergy

- Current smoking habit, high alcohol use

- Current intake of medications including vitamin supplements

- Kidney, cardiovascular, haematological, respiratory, gastrointestinal, endocrine or
central nervous system disease, as well as psychiatric disorder, active cancer within
the last five years; presence of acute inflammation (by history, physical or
laboratory examination)

- Menopause, pregnancy or lactation

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Phase 4
Type of endpoint(s)
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Data analysis
Reason for early stopping/withdrawal
Other reasons
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)
VIC
Recruitment hospital [1] 0 0
Monash Centre for Health Research and Implementation - Melbourne
Recruitment postcode(s) [1] 0 0
3168 - Melbourne

Funding & Sponsors
Primary sponsor type
Other
Name
Monash University
Address
Country
Other collaborator category [1] 0 0
Other
Name [1] 0 0
University of Victoria
Address [1] 0 0
Country [1] 0 0
Other collaborator category [2] 0 0
Other
Name [2] 0 0
University of Auckland, New Zealand
Address [2] 0 0
Country [2] 0 0

Ethics approval
Ethics application status

Summary
Brief summary
The aim of this study is to determine whether vitamin D supplementation in overweight/obese
individuals with vitamin D deficiency can improve insulin secretion and/or insulin resistance
by decreasing subclinical inflammation.

Results of the present study may help to identify new strategies to prevent type 2 diabetes
in high-risk groups (i.e. overweight and obese individuals, and individuals with a strong
family history of diabetes).

Hypothesis: That increasing plasma 25(OH)D concentrations in healthy individuals at risk for
type 2 diabetes with low vitamin D levels through vitamin D supplementation, will improve
insulin sensitivity and also insulin secretion by reducing the underlying sub-clinical
chronic inflammation.

Aims: To establish whether 16-week vitamin D supplementation given to healthy individuals
with low vitamin D levels will:

1. improve insulin sensitivity (in vivo and tissue) and/or insulin secretory function

2. determine whether this relationship is mediated by a reduced chronic inflammation
Trial website
https://clinicaltrials.gov/show/NCT02112721
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 0 0
Barbora de Courten, PhD, MD
Address 0 0
Monash University
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Address 0 0
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for scientific queries

Summary results
Other publications