Role of Vitamin D in the Prevention and Treatment of Deseases Associated With Insulin Resistance (VIDIR)

This study is not yet open for participant recruitment.
Verified December 2012 by Centre Hospitalier Universitaire de Québec, CHU de Québec
Sponsor:
Collaborator:
Canadian Diabetes Association
Information provided by (Responsible Party):
Centre Hospitalier Universitaire de Québec, CHU de Québec
ClinicalTrials.gov Identifier:
NCT01779908
First received: January 24, 2013
Last updated: January 29, 2013
Last verified: December 2012
  Purpose

Prospective, randomized and placebo-controlled 6-month trial of vitamin D supplementation in 144 Caucasian and vitamin D-deficient men and postmenopausal women aged of 50 years + with the hypertriglyceridemic waist phenotype and a BMI ≤40 kg/m2. Participants will be randomized by sex and BMI The primary aim is to compare the effect of daily vitamin D3 (cholecalciferol, 5000 IU) vs. placebo for 6 mo on insulin sensitivity (M-value by the gold standard method, the euglycemic hyperinsulinemic clamp). Secondary aims are to evaluate the effects of vitamin D3 vs. placebo on other indices of glucose metabolism, the lipid profile, blood pressure and anthropometric measurements. Questionnaires on physical activity and sunlight exposure, and a food frequency questionnaire will be administered at 0 and 6 mo to adjust for confounding factors. At 0 and 6 mo, biochemical markers associated with insulin sensitivity will be measured : changes in serum 25(OH)D with changes in blood markers associated with insulin sensitivity [hs-CRP, inflammatory cytokines (IL-6 and TNF-alpha), adiponectin, leptin, total and undercarboxylated osteocalcin].

This research project intends to test 2 major hypotheses: (1) that vitamin D deficiency plays a causal role in the pathogenesis of insulin resistance in humans; and (2) that vitamin D increases insulin sensitivity.


Condition Intervention
Vitamin D-deficient
Insulin-resistant
Dietary Supplement: Vitamin D
Other: Placebo

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Prevention
Official Title: Role of Vitamin D in the Prevention and Treatment of Deseases Associated With Insulin Resistance

Resource links provided by NLM:


Further study details as provided by Centre Hospitalier Universitaire de Québec, CHU de Québec:

Primary Outcome Measures:
  • Change from baseline in peripheral insulin sensitivity at 6 months [ Time Frame: 0 and 6 months ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Change from baseline in glucose homeostasis at 6 months [ Time Frame: 0 and 6 months ] [ Designated as safety issue: No ]

Other Outcome Measures:
  • Changes from baseline in cytokines/adipokines at 6 months [ Time Frame: 0 and 6 months ] [ Designated as safety issue: No ]

Estimated Enrollment: 144
Study Start Date: January 2013
Estimated Study Completion Date: January 2016
Estimated Primary Completion Date: January 2015 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Vitamin D supplementation
5000 UI vitmamin D supplementation for 6 months
Dietary Supplement: Vitamin D
Placebo Comparator: Placebo
Placebo pill for 6 months
Other: Placebo

Detailed Description:

Part 1: Prospective, randomized and placebo-controlled 6-month trial of vitamin D supplementation in 144 Caucasian and vitamin D-deficient [serum 25(OH)D ≤50 nM] men and postmenopausal women aged of 50 years + with the hypertriglyceridemic waist phenotype (waist circumference above 90 cm + fasting triglycerides above 2.0 mM in men; waist circumference above 85 cm + fasting triglycerides above 1.5 mM in women) and a BMI ≤40 kg/m2. Participants will be randomized by sex and BMI (<30 kg/m2 vs. above 30 kg/m2). The primary aim is to compare the effect of daily vitamin D3 (cholecalciferol, 5000 IU) vs. placebo for 6 mo on insulin sensitivity (M-value by the gold standard method, the euglycemic hyperinsulinemic clamp). Secondary aims are to evaluate the effects of vitamin D3 vs. placebo on other indices of glucose metabolism (fasting glucose, 2-h plasma glucose post OGTT, HbA1c, insulin sensitivity index (HOMA-IS using fasting glucose and insulin), insulin secretion index (HOMA-B using fasting glucose and C-peptide), insulinogenic index [(C-peptide at 30 min post OGTT - C-peptide at 0 min)/(glucose at 30 min post OGTT - glucose at 0 min)] and disposition index (insulinogenic index x M-value)), the lipid profile, blood pressure and anthropometric measurements (weight, waist and hip circumference, fat mass by dual-energy X-ray absorptiometry). Questionnaires on physical activity and sunlight exposure, and a food frequency questionnaire will be administered at 0 and 6 mo to adjust for confounding factors. At 0 and 6 mo, biochemical markers associated with insulin sensitivity will be measured (point 2).

Part 2: Mechanistic studies comparing, before and after vitamin D3 supplementation, changes in serum 25(OH)D with changes in blood markers associated with insulin sensitivity [hs-CRP, inflammatory cytokines (IL-6 and TNF-alpha), adiponectin, leptin, total and undercarboxylated osteocalcin].

  Eligibility

Ages Eligible for Study:   50 Years to 80 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Caucasian men and postmenopausal women (absence of menstrual cycles for ≥12 mo)
  • ≥50 yrs
  • vitamin D deficiency [serum 25(OH)D concentration ≤50 nM]
  • hypertriglyceridemic waist phenotype (waist circumference >90 cm plus fasting triglycerides >2.0 mM in men; waist circumference >85 cm plus fasting triglycerides >1.5 mM in women)

Exclusion Criteria:

  • Type 2 diabetes under drug therapy
  • HbA1c >7%
  • BMI >40 kg/m2
  • medication influencing vitamin D or glucose metabolism in the last 3 mo (including estrogen replacement)
  • regular consumption of supplements containing >400 IU/d of vitamin D3 over the last 2 mo; renal insufficiency
  • cirrhosis, intestinal malabsorption (bypass surgery, celiac disease, etc) or osteoporosis
  • history of nephrolithiasis
  • hypercalcemia (>2.6 mM)
  • hypercalciuria (>0.6 fasting urine Ca/creatinine ratio)
  • >5% change in weight in the last 3 mo
  • diseases affecting glucose metabolism (e.g. hyperthyroidism)
  • pacemaker (for bio-impedance only)
  • inability to provide informed consent and complete questionnaires due to physical or mental problems
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT01779908

Contacts
Contact: Anne-Sophie Morisset, PhD 1-418-525-4444 ext 48729 anne-sophie.morisset@crchul.ulaval.ca
Contact: Claudia Gagnon, Dr 1-418-525-4444 ext 48535 claudia.gagnon@crchuq.ulaval.ca

Locations
Canada, Quebec
CHU de Québec, Laval University Research Center Not yet recruiting
Quebec city, Quebec, Canada, G1V 4G2
Contact: Verson Barbara    1-418-525-4414    barbara.verson@crchuq.ulaval.ca   
Principal Investigator: Claudia Gagnon, Dr         
Sponsors and Collaborators
Centre Hospitalier Universitaire de Québec, CHU de Québec
Canadian Diabetes Association
Investigators
Principal Investigator: Claudia Gagnon, Dr. CHU de Québec Research Center
  More Information

Additional Information:
No publications provided

Responsible Party: Centre Hospitalier Universitaire de Québec, CHU de Québec
ClinicalTrials.gov Identifier: NCT01779908     History of Changes
Other Study ID Numbers: F0101406, B12-12-1095
Study First Received: January 24, 2013
Last Updated: January 29, 2013
Health Authority: Canada: Health Canada

Keywords provided by Centre Hospitalier Universitaire de Québec, CHU de Québec:
Vitamin D supplementation
Insulin resistance

Additional relevant MeSH terms:
Insulin Resistance
Hyperinsulinism
Glucose Metabolism Disorders
Metabolic Diseases
Vitamin D
Ergocalciferols
Vitamins
Insulin
Bone Density Conservation Agents
Physiological Effects of Drugs
Pharmacologic Actions
Micronutrients
Growth Substances
Hypoglycemic Agents

ClinicalTrials.gov processed this record on April 14, 2014