Vitamin D and Calcium Homeostasis for Prevention of Type 2 Diabetes (CaDDM)

July 8, 2019 updated by: Tufts Medical Center
The purpose of the randomized trial is to quantify the effect of vitamin D and calcium supplementation on beta-cell function, insulin sensitivity, glucose tolerance and systemic inflammation and other cardiometabolic outcomes in ambulatory adults at high risk for type 2 diabetes.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

There is animal and human observational evidence to suggest that vitamin D and calcium are important in modifying t2DM risk but there are critical gaps in our knowledge about the clinical magnitude of the association with t2DM and potential mechanisms in humans. We are conducting a randomized trial to quantify the effect of vitamin D and calcium supplementation on beta-cell function, insulin sensitivity, glucose tolerance and systemic inflammation and other cardiometabolic outcomes in ambulatory adults at high risk for t2DM. We anticipate that the research proposed in this application is significant because it will provide the basis for defining feasible nutritional interventions that promotes prevention of t2DM. Based on the results of the proposed studies and future work in this area, vitamin D and calcium supplementation can assume an important role in the treatment of t2DM and in the prevention of the disease in the 41 million Americans who are at risk of developing t2DM.

Study Type

Interventional

Enrollment (Actual)

92

Phase

  • Phase 2
  • Phase 1

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
    • Massachusetts
      • Boston, Massachusetts, United States, 02111
        • Tufts-New England Medical Center

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

40 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Ethnicity: all ethnic groups
  • Gender: men and women

  • Age

    1. Lower age limit: 40 years inclusive
    2. Upper age limit: NONE

  • BMI

    1. Lower BMI limit: 25 inclusive
    2. Upper BMI limit: 40 inclusive

  • Glucose Intolerance / Mild Diabetes defined as

    1. Fasting glucose ≥100 mg/dl OR
    2. 2-hr glucose after OGTT ≥140 mg/dl OR
    3. 5.8 ≤ Hemoglobin A1c ≤ 7

Major Exclusion Criteria:

  • Diabetes requiring pharmacotherapy
  • Smoking
  • Hyperparathyroidism
  • Hypercalcemia (Calcium > 10.5 mg/dl)
  • Kidney stone
  • Pregnancy

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: Randomized
  • Interventional Model: Factorial Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Other: 1
Vitamin D3 2,000 IU daily plus Calcium Carbonate 400 mg twice daily
Drug: Vitamin D3 2,000 IU orally once daily
Vitamin D3 2,000 IU orally once daily
Drug: Calcium Carbonate 400 mg orally twice daily
Calcium Carbonate 400 mg orally twice daily
Other: 2
Vitamin D3 2,000 IU daily plus Calcium-Placebo twice daily
Drug: Vitamin D3 2,000 IU orally once daily
Vitamin D3 2,000 IU orally once daily
Drug: Calcium-Placebo
Calcium-Placebo
Other: 3
Vitamin D3-Placebo plus Calcium Carbonate 400 mg twice daily
Drug: Calcium Carbonate 400 mg orally twice daily
Calcium Carbonate 400 mg orally twice daily
Drug: Vitamin D3-Placebo
Vitamin D3-Placebo
Other: 4
Vitamin D3-Placebo plus Calcium-Placebo
Drug: Calcium-Placebo
Calcium-Placebo
Drug: Vitamin D3-Placebo
Vitamin D3-Placebo

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Chang in Disposition Index, a Measure of Beta Cell Function
Time Frame: baseline and 4 months
Range is 0 to infinity Lower is better.
baseline and 4 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in Hemoglobin A1c
Time Frame: Baseline to 4 months
This outcome measures change in Hemoglobin A1c, a measure of glycemia
Baseline to 4 months

Collaborators and Investigators

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

Sponsor

Tufts Medical Center

Collaborators

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Investigators

  • Principal Investigator: Anastassios G Pittas, MD MS, Tufts Medical Center

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Helpful Links

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

September 1, 2007

Primary Completion (Actual)

November 1, 2009

Study Completion (Actual)

November 1, 2009

Study Registration Dates

First Submitted

February 16, 2007

First Submitted That Met QC Criteria

February 16, 2007

First Posted (Estimate)

February 19, 2007

Study Record Updates

Last Update Posted (Actual)

July 30, 2019

Last Update Submitted That Met QC Criteria

July 8, 2019

Last Verified

July 1, 2019

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • DK76092 (completed)
  • R01DK076092 (U.S. NIH Grant/Contract)
  • DK76092

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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