Glucose Metabolism Effects of Vitamin D Supplementation in Prediabetes (VitDmet)

This study has been completed.
Sponsor:
Collaborators:
Academy of Finland
Juho Vainio Foundation
Finnish Foundation for Cardiovascular Research
Finnish Diabetes Research Foundation
Information provided by (Responsible Party):
Tomi-Pekka Tuomainen, University of Eastern Finland
ClinicalTrials.gov Identifier:
NCT01479933
First received: August 29, 2011
Last updated: March 3, 2013
Last verified: March 2013
  Purpose

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.


Condition Intervention
Prediabetic State
Overweight
Obese
Dietary Supplement: Vitamin D3
Dietary Supplement: Placebo
Dietary Supplement: Vitamin D 80

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Official Title: Randomized Controlled Trial of Vitamin D Supplementation on Glucose Metabolism in Subjects With Components of the Metabolic Syndrome

Resource links provided by NLM:


Further study details as provided by University of Eastern Finland:

Primary Outcome Measures:
  • Insulin sensitivity [ Time Frame: Six months ] [ Designated as safety issue: No ]
    Change in insulin sensitivity measured by oral glucose tolerance test at baseline and after 6 months


Secondary Outcome Measures:
  • Peripheral blood mononuclear cell gene expression [ Time Frame: Six months ] [ Designated as safety issue: No ]
  • Inflammation [ Time Frame: Baseline to six months ] [ Designated as safety issue: No ]
    Change in inflammation measured as serum cytokines and adipose tissue inflammation at baseline and after 6 months

  • Adipose tissue gene expression [ Time Frame: Six months ] [ Designated as safety issue: No ]

Enrollment: 73
Study Start Date: September 2011
Study Completion Date: May 2012
Primary Completion Date: May 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Vitamin D 40
Vitamin D3 40 micrograms (1600 IU) per day
Dietary Supplement: Vitamin D3
Vitamin D3 40 micrograms (1600 IU) per day
Experimental: Vitamin D 80
Vitamin D3 80 micrograms (3200 IU) per day
Dietary Supplement: Vitamin D 80
Vitamin D3 80 micrograms (3200 IU) per day
Placebo Comparator: Placebo Dietary Supplement: Placebo
Inactive placebo

  Eligibility

Ages Eligible for Study:   60 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

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.
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT01479933

Locations
Finland
University of Eastern Finland, Kuopio Campus
Kuopio, Finland, 70211
Sponsors and Collaborators
University of Eastern Finland
Academy of Finland
Juho Vainio Foundation
Finnish Foundation for Cardiovascular Research
Finnish Diabetes Research Foundation
Investigators
Principal Investigator: Tomi-Pekka Tuomainen, MD, PhD University of Eastern Finland
  More Information

Additional Information:
No publications provided

Responsible Party: Tomi-Pekka Tuomainen, Professor, University of Eastern Finland
ClinicalTrials.gov Identifier: NCT01479933     History of Changes
Other Study ID Numbers: VitDmet
Study First Received: August 29, 2011
Last Updated: March 3, 2013
Health Authority: Finland: Ethics Committee

Keywords provided by University of Eastern Finland:
vitamin D
cholecalciferol
supplementation
prediabetic state
obesity
glucose metabolism
gene expression
transcriptomics
epigenomics
immunological function
insulin sensitivity
peripheral mononuclear cells

Additional relevant MeSH terms:
Prediabetic State
Overweight
Diabetes Mellitus
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Body Weight
Signs and Symptoms
Cholecalciferol
Vitamin D
Ergocalciferols
Vitamins
Micronutrients
Growth Substances
Physiological Effects of Drugs
Pharmacologic Actions
Bone Density Conservation Agents

ClinicalTrials.gov processed this record on April 23, 2014