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Type 2 Diabetes MellitusPhase 2EVIDENCENCT01726777

Effect of Vitamin D Supplementation on Glucose Tolerance in Subjects at Risk for Diabetes With Low Vitamin D.

A Phase 2 study testing Vitamin D in people with Type 2 Diabetes Mellitus and Vitamin D Deficiency, run by University of Toronto at 3 sites in Canada.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

Type 2 diabetes (T2D) is an increasingly common and serious condition. Studies show that low vitamin D levels are associated with increased diabetes risk and that vitamin D may protect against diabetes by reducing chronic inflammation and improving insulin sensitivity and insulin secretion. Read more about this study

Who is it for?
Ages 18 to 75 years
What is being tested?
Vitamin D
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
71 participants
Where
3 sitesCanada
Study dates
Oct 2012to Sep 2015
Phase
Phase 2
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 75 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • male or non-pregnant, non-lactating females, aged 18-75
  • volunteered to participate by signing the consent form
  • BMI <40kg/ m2
  • vitamin D insufficient, defined as: serum 25(OH) vitamin D3 (25(OH)D) concentration ≤65nmol/ L
  • increased risk for diabetes, defined as: FINDRISC score >10 for Caucasians or >6 for non-Caucasians OR presence of metabolic syndrome
  • dysglycemia, defined as:fasting serum glucose 5.6 to 6.9 mmol/L, inclusive OR HbA1c 0.054 to 0.064, inclusive
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  • systolic blood pressure ≤150/95 mmHg if not being treated for hypertension or ≤140/90 mmHg if on treatment for hypertension.
  • taking no prescription drugs, or stable (for at least 6 weeks) dose of birth control pill, or drug(s) used to treat hypertension, hyperlipidemia, depression or other mental illness or hypothyroid.
  • taking no supplements, or stable (for at least 6 weeks) dose of supplement(s).

Who cannot join

  • subjects not meeting all inclusion criteria
  • history of renal failure or liver disease
  • serum creatinine >1.8 times upper limit of normal (ULN)
  • serum aspartate or alanine transaminase (AST,ALT) >3 times ULN
  • current use of drug or drugs to treat diabetes or use of steroids or pancreatic enzymes
  • within 6 weeks of randomization, change in dose of supplements or drug(s) used to treat hypertension, hyperlipidemia, depression or other mental illness or hypothyroid.
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  • use of antibiotics within 3 months.
  • medical or surgical event requiring hospitalization within 3 months of randomization
  • presence of any condition affecting nutrient absorption
  • intolerance to cheese
  • plan to travel outside Canada for more than 14 consecutive days during the trial

Trial locations and contacts

3 sites in 1 country.

Canada3 sites

  • University of Guelph

    Guelph, Ontario, N1G 2W1

  • Institut de recherches cliniques de Montréal

    Montreal, Quebec, H2W 1R7

  • Glycemic Index Laboratories

    Toronto, Ontario, M5C 2N8

Other trials in Canada

About this study

Official title: Effect of Vitamin D Supplementation on Oral Glucose Tolerance in Subjects Exhibiting Marginal Vitamin D Status and an Increased Risk of Developing Diabetes.

Type 2 diabetes (T2D) is an increasingly common and serious condition. Studies show that low vitamin D levels are associated with increased diabetes risk and that vitamin D may protect against diabetes by reducing chronic inflammation and improving insulin sensitivity and insulin secretion. However, no studies have been able to show that vitamin D actually reduces post-prandial blood glucose levels, the most clinically relevant marker of diabetes. Previously the investigators have shown that cheddar cheese and low-fat cheese can be fortified with high levels of vitamin D and that this cheese is at least as a effective as vitamin D supplements in raising blood vitamin D levels.

The main purpose of this study is to see whether vitamin D enriched cheese can improve oral glucose tolerance (reduce blood glucose 2 hours after consuming a drink containing 75g sugar) in people who have low vitamin D levels and are at risk for developing T2D.

Other aims are to determine the effect of vitamin D may on insulin sensitivity, insulin secretion, markers of inflammation, blood cholesterol levels, and safety markers such as urinary calcium excretion.

Read the detailed description

Type 2 diabetes (T2D) is an increasingly prevalent and serious condition whose risk appears to be increased by low serum vitamin D concentrations. Epidemiological studies show an association between increased diabetes risk and low serum vitamin D and studies suggest that vitamin D may protect against diabetes by reducing chronic inflammation and improving insulin sensitivity and insulin secretion. Although clinical studies show some of these effects, no studies have been able to show that vitamin D supplementation reduces post-prandial blood glucose, the most clinically relevant marker of diabetes and dysglycemia. Previously, the investigators showed that cheddar cheese and low-fat cheese can be fortified with high levels of vitamin D3 (28,000IU/ 30g portion) and that, in this form, it is at least as a effective as vitamin D3 supplements in raising serum vitamin D concentrations. Since post-prandial glucose is most sensitive to changes in insulin sensitivity the main purpose of this study is to determine the effect of vitamin D supplementation on oral glucose tolerance (ie. serum glucose 2h after 75g oral glucose) in individuals who are at risk for developing T2D. Secondary objective are to determine the effect of vitamin D supplementation on insulin sensitivity, insulin secretion, inflammatory markers, blood lipids and markers of safety including serum parathyroid hormone levels and urinary calcium excretion.

Being tested
Control, Vitamin D
Keywords
Randomized controlled clinical trial, Diabetes, Vitamin D, Oral glucose tolerance, Blood glucose, Insulin resistance
Medical subject headings
Diabetes Mellitus, Type 2, Vitamin D Deficiency, Diabetes Mellitus, Insulin Resistance

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • ControlDietary supplement

    Normal cheddar cheese

  • Vitamin DDietary supplement

    Also called Vitamin D3

    Vitamin D3 supplemented cheddar cheese

Study groups in NCT01726777
Study groupRoleWhat they receive
ControlPlacebo comparator30g normal cheddar cheese once per week
Receives: Dietary Supplement: Control
Vitamin DExperimental30g cheddar cheese containing 28,000IU vitamin D once per week
Receives: Dietary Supplement: Vitamin D

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Change in plasma glucose concentration 2 hours after consuming 75g oral glucose (2 hour PC glucose, or 2hrPC glucose)

    Change from baseline in plasma glucose concentration 2 hours after consuming 75g oral glucose.

    Measured: 24 Weeks

Secondary outcomes (10)

  1. Change in insulin resistance assessed using the homeostasis model assessment of insulin resistance (HOMA-IR)

    Change from baseline in homeostasis model assessment of insulin resistance (HOMA-IR) which is G*I/22.5 where G is fasting plasma glucose (mmol/L) and I is fasting plasma insulin (uU/mL).

    Measured: 24 weeks

  2. Change in Matsuda insulin sensitivity index

    Change from baseline in Matsuda insulin sensitivity index which is (10,000/square root of [fasting glucose x fasting insulin] x [mean glucose x mean insulin during OGTT]).

    Measured: 24 weeks

  3. Change in insulin secretion assessed using the homeostasis model assessment of beta-cell function (HOMA-B)

    Change from baseline in homeostasis model assessment of beta-cell function (HOMA-B) which is 20*I/(G-3.5) where I is fasting plasma insulin (uU/mL) and G is fasting plasma glucose (mmol/L).

    Measured: 24 weeks

  4. Change in insulinogenic index

    Change from baseline in insulinogenic index which is dI0-30/dG0-30, where dI0-30 is the change in plasma insulin between fasting and 30min and dG0-30 is the change in plasma glucose between fasting and 30min after 75g oral glucose.

    Measured: 24 weeks

  5. Change in disposition index derived from HOMA-IR and HOMA-B

    Change from baseline in disposition index which is HOMA-B/HOMA-IR, which have been defined above.

    Measured: 24 weeks

  6. Change in disposition index based on oral glucose tolerance test (OGTT)

    Change from baseline in ISSI-2 index which is AUCi/AUCg x Matsuda insulin sensitivity index, where AUCi and AUCg, respectively, are the total areas under the plasma insulin and glucose response curves after 75g oral glucose and Matsuda insulin sensitivity index has been defined above.

    Measured: 24 weeks

  7. Change in fasting plasma glucose

    Change from baseline in fasting plasma glucose

    Measured: 24 weeks

  8. Change in glucose area under the curve

    Change from baseline in incremental area under the glucose response curve after 75g oral glucose

    Measured: 24 weeks

  9. Change in glycated hemoglobin

    Change from baseline in glycated hemoglobin (HbA1c)

    Measured: 24 weeks

  10. Correlation between changes in serum 25-hydroxy-vitamin D concentration (25(OH)D) and changes in 2 hour PC glucose

    Correlation between change from baseline in serum 25-hydroxy-vitamin D concentration and change from baseline in plasma glucose 2 hours after 75g oral glucose.

    Measured: 24 weeks

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted15 Nov 2012 (estimated)
  2. Study startOct 2012
  3. Primary completionSep 2015
  4. Study completionSep 2015

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 2
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Parallel groups
Masking
Quadruple blind
Who is masked
Participant, Care provider, Investigator, Outcomes assessor
Enrolment
71 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT01726777
Sponsor's protocol ID
UTRS-27546
Acronym
EVIDENCE
Status last verified
Sep 2015
First submitted
9 Nov 2012
Last updated
17 Sep 2015
Results posted
No
Data monitoring committee
No

Questions about this trial

What is this clinical trial studying?

A Phase 2 study testing Vitamin D in people with Type 2 Diabetes Mellitus and Vitamin D Deficiency, run by University of Toronto at 3 sites in Canada.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 9 inclusion and 11 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 17 Sep 2015. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 3 sites in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Change in plasma glucose concentration 2 hours after consuming 75g oral glucose (2 hour PC glucose, or 2hrPC glucose) (time frame: 24 Weeks). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT01726777.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 17 Sep 2015; AzTrials last refreshed its copy on 8 Nov 2026.

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