Glucose Metabolism Effects of Vitamin D Supplementation in Prediabetes

Overweight Clinical Trial

— VitDmet  

Official title:

Randomized Controlled Trial of Vitamin D Supplementation on Glucose Metabolism in Subjects With Components of the Metabolic Syndrome

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01479933
• Other study ID #: VitDmet
• Status: Completed
• Phase: N/A
• First received: August 29, 2011
• Last updated: March 3, 2013
• Start date: September 2011
• Est. completion date: May 2012

Study information

• Verified date: March 2013
• Source: University of Eastern Finland
• Contact: n/a
• Is FDA regulated: No
• Health authority: Finland: Ethics Committee
• Study type: Interventional

Clinical Trial Summary

Vitamin D deficiency is widespread throughout the world, and the deficiency has been associated with several chronic diseases, such as cardiovascular diseases and diabetes. In Nordic countries, like in Finland, there is a particular variation in vitamin D status, and during wintertime, when there is no exposure to ultraviolet-B light from the sun, serum concentrations of vitamin D decrease substantially. In Finland, some 40% of middle-aged men and one third of women also have some degree of impairment of glucose metabolism.

The purpose of this trial is to investigate the effects of two different daily doses of vitamin D on glucose metabolism in men 60 years of age or older and who are vitamin D deficient, have a high body mass index and at least two characteristics of cardio-metabolic syndrome.

Altogether 102 subjects with low serum calcidiol (<60 nmol/L) will be recruited and randomized to one of the three groups: 1) 40 µg/d vitamin D3, 2) 80 µg/d vitamin D3 or 3) placebo. The supplementation period will last for 6 months from September 2011 to March 2012.

The main hypotheses of the trial are: (1.) Vitamin D supplementation will improve glucose and insulin metabolism in people with a low baseline vitamin D status, in a dose-dependent manner. (2.) Vitamin D supplementation will have an effect on the expression of genes involved in glucose and insulin metabolism and inflammation. (3.) Vitamin D supplementation will have an effect on epigenetic changes in key genes participating in vitamin D metabolism.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 73
• Est. completion date: May 2012
• Est. primary completion date: May 2012
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 60 Years and older

Eligibility

Inclusion Criteria:

• Age 60 years or older

• Serum calcidiol <75 nmol/L

• Body mass index 25-35 kg/m2

• Impaired fasting glucose or impaired glucose tolerance (fasting glucose 5.6-7.0 mmol/L or 2h oral glucose tolerance test glucose 7.8-11.0 mmol/L)

Exclusion Criteria:

• Any chronic disease and condition, which may hamper to follow the intervention protocol (such as alcohol abuse)

• Any chronic disease or therapy which may mask or interact with the investigated effects (such as diabetes or systemic corticosteroid therapy)

• Any disease or state that raises a vitamin D related safety concern (such as chronic liver, thyroid or kidney disease, hypercalcemia, sarcoidosis or other granulomatous diseases such as active chronic tuberculosis or Wegener's granulomatosis)

• Use of supplements yielding vitamin D over 20 µg/d and unwillingness to discontinue the use.

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Obese
• Overweight
• Prediabetic State

Intervention

Dietary Supplement:
• Vitamin D3
Vitamin D3 40 micrograms (1600 IU) per day
• Placebo
Inactive placebo
• Vitamin D 80
Vitamin D3 80 micrograms (3200 IU) per day

Locations

Country	Name	City	State
Finland	University of Eastern Finland, Kuopio Campus	Kuopio

Sponsors (5)

Lead Sponsor	Collaborator
University of Eastern Finland	Academy of Finland, Diabetes Research Foundation, Finland, Finnish Foundation for Cardiovascular Research, Juho Vainio Foundation

Country where clinical trial is conducted

Finland, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Insulin sensitivity	Change in insulin sensitivity measured by oral glucose tolerance test at baseline and after 6 months	Six months	No
Secondary	Peripheral blood mononuclear cell gene expression		Six months	No
Secondary	Inflammation	Change in inflammation measured as serum cytokines and adipose tissue inflammation at baseline and after 6 months	Baseline to six months	No
Secondary	Adipose tissue gene expression		Six months	No

External Links

•   University of Eastern Finland