Vitamin D for the Prevention of Diabetes Type 2

Study Overview
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Brief Summary
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The prevalence of type 2 diabetes is increasing, which for most societies has considerable consequences not only regarding health but also economy. Type 2 diabetes develops through a prediabetic stage with impaired glucose tolerance. Intervention at this stage with change in lifestyle or with medication may prevent such progression. There are indications that vitamin D is of importance in glucose metabolism, and that supplementation with vitamin D may increase both insulin secretion and insulin sensitivity. Accordingly, supplementation with vitamin D may improve glucose tolerance and potentially prevent the development of type 2 diabetes in subjects at risk. However, this has so far not been demonstrated in a prospective, randomised clinical study. In the present study we will therefore include 600 subjects with impaired glucose tolerance (or impaired fasting glucose) detected in the Tromso study 2007/2008 and randomize to supplementation with vitamin D 20.000IU per week or placebo for 5 years. A glucose tolerance test will be performed each year, and development of type 2 diabetes will be the main endpoint.

Official Title
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Prevention of Type 2 Diabetes With Vitamin D Supplementation in Subjects With Reduced Glucose Tolerance Detected in the Tromso Study 2007/2008

Conditions
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Impaired Glucose Tolerance

Intervention / Treatment
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* Drug: cholecalciferol
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Impaired glucose tolerance Exclusion Criteria: Serious heart disease Renal stone disease Hypercalcemia Sarcoidosis

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1<br>Cholecalciferol 20.000 IU per week for 5 years | Drug: cholecalciferol<br>* 20.000 IU cholecalciferol per week for 5 years versus placebo<br>* Other names: vitamin D;|
| Placebo Comparator: 2<br> | Drug: Placebo<br>* Placebo capsule once a week, identical to cholecalciferol capsule<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| development of diabetes type 2 |  | 5 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change in glucose metabolism |  | 5 years | 
| change in lipid status |  | 5 years | 
| change in mood |  | 5 years | 
| change in BMD hip |  | 5 years | 
| change in intima media thickness carotid artery |  | 5 years | 
| change in frequency of infections |  | 5 years | 
| change in blood pressure |  | 5 years | 
| Change in Insulin sensitivity |  | 5 years | 
| change in HbA1c |  | 5 years | 
| change in weight |  | 5 years | 
| change in telomer length |  | 5 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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diabetes, vitamin D, cholecalciferol, glucose tolerance