Effect of Vitamin D Deficiency and Vitamin D Supplementation on Glucose Metabolism

October 16, 2008 updated by: University of Minnesota

Improved Insulin Sensitivity With Therapeutic Vitamin D Replacement in Pre-Diabetic Vitamin D Deficient Individuals

This study was intended to evaluate the effect of vitamin D supplementation on insulin sensitivity and pancreatic islet beta-cell function. Our hypothesis was that vitamin D supplementation to normal levels in patients with impaired fasting glucose will result in improved insulin sensitivity and improved beta cell function.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

A modified frequently sampled intravenous glucose tolerance (mFSIGT) test was used. On day 0, baseline 22 time point mFSIGT was performed. Subjects were then treated with cholecalciferol (vitamin D3) supplementation - 10,000 IU/day - for 28 consecutive days. mFSIGT was then repeated measuring glucose, insulin and c-peptide at all time points. 25-OH vitamin D, PTH, and calcium were also measured at time point 0 pre and post vitamin D supplementation. Data was analyzed using the Bergman/Boston minimal model for insulin homeostasis with MinMod Millennium software.

Study Type

Interventional

Enrollment (Actual)

12

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Minnesota
      • Minneapolis, Minnesota, United States, 55455
        • University of Minnesota, Division of Endocrinology

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

14 years to 61 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Impaired fasting glucose
  • Adult, age between 18 and 65
  • Serum vitamin D level below 30 ng/mL

Exclusion Criteria:

  • History of nephrolithiasis
  • Any medications that can effect insulin sensitivity or beta cell function (i.e. antipsychotics, metformin)
  • Pregnancy
  • Liver disease
  • Renal disease

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Non-Randomized
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: 1
Each subject was evaluated and data was collected before and after the intervention
Dietary supplement: Cholecalciferol (vitamin D3)
Oral capsules of cholecalciferol, 5000 IU/ capsule, two capsules daily for one month.
Other Names:
  • Cholecalciferol by BIO-TECH Pharmacal, Inc.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Assessment of insulin sensitivity before and after oral vitamin D3 supplementation with 10,000 IU/day for one month.
Time Frame: At baseline and after 4 weeks of vitamin D supplementation
At baseline and after 4 weeks of vitamin D supplementation

Secondary Outcome Measures

Outcome Measure
Time Frame
Monitor effect of vitamin D supplementation with 10,000 IU/day for one month on serum calcium and parathyroid hormone levels.
Time Frame: One month
One month
Assess effect of vitamin D supplementation on beta cell function as measured by analysis of data collected through a modified FSIGT test.
Time Frame: One month
One month

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of Minnesota

Collaborators

Hennepin Healthcare Research Institute

Investigators

  • Study Director: Cary Mariash, MD, University of Minnesota
  • Principal Investigator: Shaban Nazarian, MD, University of Minnesota

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

January 1, 2007

Primary Completion (Actual)

June 1, 2008

Study Completion (Actual)

June 1, 2008

Study Registration Dates

First Submitted

September 8, 2008

First Submitted That Met QC Criteria

September 8, 2008

First Posted (Estimate)

September 9, 2008

Study Record Updates

Last Update Posted (Estimate)

October 20, 2008

Last Update Submitted That Met QC Criteria

October 16, 2008

Last Verified

October 1, 2008

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 0609M92006

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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