Effect of Vitamin D Supplementation on Glucose Tolerance in Subjects at Risk for Diabetes With Low Vitamin D.

NCT01726777 | Completed Phase 2

• 1 other identifier: UTRS-27546
• Study Type: interventional
• Target: 71
• Locations: 1 country
• Sites: 3

Brief Summary

Type 2 diabetes (T2D) is an increasingly common and serious condition. Studies show that low vitamin D levels are associated with increased diabetes risk and that vitamin D may protect against diabetes by reducing chronic inflammation and improving insulin sensitivity and insulin secretion. However, no studies have been able to show that vitamin D actually reduces post-prandial blood glucose levels, the most clinically relevant marker of diabetes. Previously the investigators have shown that cheddar cheese and low-fat cheese can be fortified with high levels of vitamin D and that this cheese is at least as a effective as vitamin D supplements in raising blood vitamin D levels. The main purpose of this study is to see whether vitamin D enriched cheese can improve oral glucose tolerance (reduce blood glucose 2 hours after consuming a drink containing 75g sugar) in people who have low vitamin D levels and are at risk for developing T2D. Other aims are to determine the effect of vitamin D may on insulin sensitivity, insulin secretion, markers of inflammation, blood cholesterol levels, and safety markers such as urinary calcium excretion.

Conditions

Type 2 Diabetes Mellitus; Vitamin D Deficiency

Keywords

Randomized controlled clinical trial; Diabetes; Vitamin D; Oral glucose tolerance; Blood glucose; Insulin resistance

Outcome Measures

Primary Outcomes (1)

• Change in plasma glucose concentration 2 hours after consuming 75g oral glucose (2 hour PC glucose, or 2hrPC glucose)

  Change from baseline in plasma glucose concentration 2 hours after consuming 75g oral glucose.

  24 Weeks

Secondary Outcomes (10)

• Change in insulin resistance assessed using the homeostasis model assessment of insulin resistance (HOMA-IR)

  24 weeks

• Change in Matsuda insulin sensitivity index

  24 weeks

• Change in insulin secretion assessed using the homeostasis model assessment of beta-cell function (HOMA-B)

  24 weeks

• Change in insulinogenic index

  24 weeks

• Change in disposition index derived from HOMA-IR and HOMA-B

  24 weeks

Other Outcomes (15)

• Fasting serum 25(OH)D

  24 weeks

• Change in serum 25(OH)D

  24 weeks

• Change in serum total cholesterol

  24 weeks

Study Arms (2)

Control

PLACEBO COMPARATOR

30g normal cheddar cheese once per week

Dietary Supplement: Control

Vitamin D

EXPERIMENTAL

30g cheddar cheese containing 28,000IU vitamin D once per week

Dietary Supplement: Vitamin D

Interventions

Control DIETARY_SUPPLEMENT

Normal cheddar cheese

Control

Vitamin D DIETARY_SUPPLEMENT

Vitamin D3 supplemented cheddar cheese

Also known as: Vitamin D3

Vitamin D

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• male or non-pregnant, non-lactating females, aged 18-75
• volunteered to participate by signing the consent form
• BMI \<40kg/ m2
• vitamin D insufficient, defined as: serum 25(OH) vitamin D3 (25(OH)D) concentration ≤65nmol/ L
• increased risk for diabetes, defined as: FINDRISC score \>10 for Caucasians or \>6 for non-Caucasians OR presence of metabolic syndrome
• dysglycemia, defined as:fasting serum glucose 5.6 to 6.9 mmol/L, inclusive OR HbA1c 0.054 to 0.064, inclusive
• systolic blood pressure ≤150/95 mmHg if not being treated for hypertension or ≤140/90 mmHg if on treatment for hypertension.
• taking no prescription drugs, or stable (for at least 6 weeks) dose of birth control pill, or drug(s) used to treat hypertension, hyperlipidemia, depression or other mental illness or hypothyroid.
• taking no supplements, or stable (for at least 6 weeks) dose of supplement(s).

You may not qualify if:

• history of renal failure or liver disease
• serum creatinine \>1.8 times upper limit of normal (ULN)
• serum aspartate or alanine transaminase (AST,ALT) \>3 times ULN
• current use of drug or drugs to treat diabetes or use of steroids or pancreatic enzymes
• within 6 weeks of randomization, change in dose of supplements or drug(s) used to treat hypertension, hyperlipidemia, depression or other mental illness or hypothyroid.
• use of antibiotics within 3 months.
• medical or surgical event requiring hospitalization within 3 months of randomization
• presence of any condition affecting nutrient absorption
• intolerance to cheese
• plan to travel outside Canada for more than 14 consecutive days during the trial

Sponsors & Collaborators

• University of Toronto: lead
• Dairy Farmers of Canada: collaborator
• Public Health Agency of Canada (PHAC): collaborator

Study Sites (3)

University of Guelph

Guelph, Ontario, N1G 2W1, Canada

Location

Glycemic Index Laboratories

Toronto, Ontario, M5C 2N8, Canada

Location

Institut de recherches cliniques de Montréal

Montreal, Quebec, H2W 1R7, Canada

Location

MeSH Terms

Conditions

Diabetes Mellitus, Type 2; Vitamin D Deficiency; Diabetes Mellitus; Insulin Resistance

Interventions

Vitamin D; Cholecalciferol

Condition Hierarchy (Ancestors)

Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases; Avitaminosis; Deficiency Diseases; Malnutrition; Nutrition Disorders; Hyperinsulinism

Intervention Hierarchy (Ancestors)

Secosteroids; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Cholestenes; Cholestanes; Sterols; Membrane Lipids; Lipids

Study Officials

• Thomas MS Wolever, DM, PhD

  University of Toronto

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: November 9, 2012
• First Posted: November 15, 2012
• Study Start: October 1, 2012
• Primary Completion: September 1, 2015
• Study Completion: September 1, 2015
• Last Updated: September 17, 2015

Record last verified: 2015-09

Locations

CA (3)