Clinical trial NCT00685594: Vitamin D for the Prevention of Diabetes Type 2
Official title: Prevention of Type 2 Diabetes With Vitamin D Supplementation in Subjects With Reduced Glucose Tolerance Detected in the Tromso Study 2007/2008
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE2
PHASE3
Conditions: Impaired Glucose Tolerance
Keywords: diabetes
vitamin D
cholecalciferol
glucose tolerance
Lead sponsor: University of Tromso
Sponsor class: OTHER
Collaborators: name: University Hospital of North Norway
First posted: 2008-05-28
Enrollment: 511
Sex: ALL
Minimum age (years): 21
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: 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.


Eligibility criteria: Inclusion Criteria:

* Impaired glucose tolerance

Exclusion Criteria:

* Serious heart disease
* Renal stone disease
* Hypercalcemia
* Sarcoidosis

Primary outcomes:
measure: development of diabetes type 2
timeFrame: 5 years
Secondary outcomes:
measure: change in glucose metabolism
timeFrame: 5 years
measure: change in lipid status
timeFrame: 5 years
measure: change in mood
timeFrame: 5 years
measure: change in BMD hip
timeFrame: 5 years
measure: change in intima media thickness carotid artery
timeFrame: 5 years
measure: change in frequency of infections
timeFrame: 5 years
measure: change in blood pressure
timeFrame: 5 years
measure: Change in Insulin sensitivity
timeFrame: 5 years
measure: change in HbA1c
timeFrame: 5 years
measure: change in weight
timeFrame: 5 years
measure: change in telomer length
timeFrame: 5 years
Other outcomes:
measure: Oral glucose tolerance response to vitamin D supplementation in relation to polymorphisms in the vitamin D system
timeFrame: 1 year
Locations:
city: Tromso
country: Norway
facility: University of Tromso
Study officials:
affiliation: University of Tromso
name: Rolf Jorde, Professor
role: PRINCIPAL_INVESTIGATOR
References:
citation: Jorde R, Sollid ST, Svartberg J, Schirmer H, Joakimsen RM, Njolstad I, Fuskevag OM, Figenschau Y, Hutchinson MY. Vitamin D 20,000 IU per Week for Five Years Does Not Prevent Progression From Prediabetes to Diabetes. J Clin Endocrinol Metab. 2016 Apr;101(4):1647-55. doi: 10.1210/jc.2015-4013. Epub 2016 Feb 1.