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Vitamin D and Type 2 Diabetes Study (D2d)

This study is ongoing, but not recruiting participants.
Sponsor:
Collaborators:
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Office of Dietary Supplements (ODS)
Information provided by (Responsible Party):
Tufts Medical Center
ClinicalTrials.gov Identifier:
NCT01942694
First received: August 9, 2013
Last updated: March 10, 2017
Last verified: March 2017
  Purpose
The goal of the Vitamin D and type 2 diabetes (D2d) study is to determine if vitamin D supplementation works to delay the onset of type 2 diabetes in people at risk for the disease and to gain a better understand how vitamin D affects glucose (sugar) metabolism.

Condition Intervention
Prediabetes Type 2 Diabetes Dietary Supplement: Vitamin D (Cholecalciferol) Other: Placebo

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
Official Title: Vitamin D and Type 2 Diabetes Study

Resource links provided by NLM:


Further study details as provided by Tufts Medical Center:

Primary Outcome Measures:
  • Time to development of diabetes [ Time Frame: Every 12 months for approximately 48 months ]

Secondary Outcome Measures:
  • Measurement of plasma 25OHD concentration. [ Time Frame: Every 12 months for approximately 48 months ]
  • Number of participants with adverse events as a measure of the safety of vitamin D supplementation. [ Time Frame: Every 3 months for approximately 48 months ]
  • Blood Pressure [ Time Frame: Every 6 months for approximately 48 months ]
  • Variability of response to vitamin D supplementation by baseline characteristic: BMI [ Time Frame: Every 12 months for approximately 48 months ]
  • Variability of response to vitamin D supplementation by baseline characteristic: waist circumference [ Time Frame: Every 12 months for approximately 48 months ]
  • Variability of response to vitamin D supplementation by baseline characteristic: age [ Time Frame: Every 12 months for approximately 48 months ]
  • Variability of response to Vitamin D supplementation by baseline characteristic: geographic location (as a proxy for sun exposure) [ Time Frame: Every 12 months for approximately 48 months ]
  • Variability of response to vitamin D supplementation by baseline characteristic: calcium intake [ Time Frame: every 12 months for approximately 48 months ]
  • Variability of response to vitamin D supplementation by baseline characteristic: 25OHD concentration [ Time Frame: Every 12 months for approximately 48 months ]
  • Variability of response to vitamin D supplementation by baseline characteristic: race (as a proxy for skin pigmentation) [ Time Frame: Every 12 months for approximately 48 months ]
  • Number of participants who discontinue study pills as a measure of the tolerability of vitamin D supplementation. [ Time Frame: Every 6 months for approximately 48 months. ]
  • Change in FPG as a continuous variable. [ Time Frame: Every 6 months for approximately 48 months ]
  • Change in 2hPG as a continuous variable. [ Time Frame: Every 12 months for approximately 48 months. ]
  • Measurement of insulin resistance (derived from the OGTT). [ Time Frame: Every 12 months for approximately 48 months ]
  • Measurement of beta cell secretion (derived from the OGTT) [ Time Frame: Every 12 months for approximately 48 months ]
  • Identification of characteristics associated with the variability in achieved 25-hydroxycholecalciferol (25OHD) concentration. [ Time Frame: Every 12 months for approximately 48 months ]
  • Change in HbA1c as a continuous variable. [ Time Frame: Every 6 months for approximately 48 months ]

Enrollment: 2382
Study Start Date: October 2013
Estimated Study Completion Date: December 2018
Estimated Primary Completion Date: November 2018 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Placebo Comparator: Placebo
One pill daily
Other: Placebo
Administered as one soft-gel pill daily by mouth
Active Comparator: Vitamin D (Cholecalciferol)
One vitamin D pill daily
Dietary Supplement: Vitamin D (Cholecalciferol)
Vitamin D (Cholecalciferol) 4000 IU, administered as 1 soft-gel pill daily by mouth.

Detailed Description:
The goal of the Vitamin D and type 2 diabetes (D2d) study is to determine if vitamin D supplementation works to delay the onset of type 2 diabetes in people at risk for the disease and to gain a better understand how vitamin D affects glucose (sugar) metabolism. Researchers at twenty US sites will enroll people with pre-diabetes (people who have higher than normal blood glucose level but not high enough to meet the diagnosis of diabetes). The study will enroll participants over approximately 2 years and participants will be followed for approximately 3 years. Participants will receive either Vitamin D or a placebo by chance. Participants will take 1 pill a day for the duration of the study. Participants will visit the study site for up to 13 scheduled visits during their participation.
  Eligibility

Ages Eligible for Study:   30 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  1. Pre-diabetes ("at increased risk for diabetes") defined by meeting 2-out-of-3 of the following glycemic criteria at the baseline visit:

    1. Fasting plasma glucose (FPG) 100-125 mg/dL
    2. 2-hour plasma glucose (2hPG) 140-199 mg/dL
    3. Hemoglobin A1c (HbA1c) 5.7-6.4%
  2. Age ≥ 30 years .(≥25 years for people of the following races: American-Indian, Alaska Native, Native Hawaiian or Other Pacific Islander).
  3. Body Mass Index 22.5 to 42 kg/m2
  4. Provision of signed and dated written informed consent prior to any study procedures.

Major Exclusion Criteria:

  1. Diabetes based on either of the following criteria:

    1. History (past 1 year) of hypoglycemic pharmacotherapy (oral or injectable medication approved by the FDA for type 2 diabetes), used for any condition (e.g. pre-diabetes, diabetes, polycystic ovarian syndrome.
    2. Meeting the diagnosis criteria for diabetes
  2. History (past 3 years) of hyperparathyroidism, nephrolithiasis or hypercalcemia.
  3. Pregnancy (past 1 year by report or positive pregnancy test at screening), intent to become pregnant in the next 4 years or unprotected intercourse. History of gestational diabetes is not an exclusion criterion.
  4. Currently breastfeeding.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01942694

  Hide Study Locations
Locations
United States, Arizona
Southwest American Indian Center
Phoenix, Arizona, United States, 85016
United States, California
University of Southern California
Los Angeles, California, United States, 90022
Stanford University
Palo Alto, California, United States, 94304
United States, Colorado
University of Colorado, Denver
Aurora, Colorado, United States, 80045
United States, Florida
Orlando VA Medical Center
Orlando, Florida, United States, 32803
Florida Hospital Translational Research Institute
Orlando, Florida, United States, 32804
United States, Georgia
Atlanta VA Medical Center
Decatur, Georgia, United States, 30033
United States, Illinois
Northwestern University
Chicago, Illinois, United States, 60611
United States, Kansas
University of Kansas Medical Center
Kansas City, Kansas, United States, 66205
United States, Louisiana
Pennington Biomedical Research Center
Baton Rouge, Louisiana, United States, 70808
Tulane University Health Sciences
New Orleans, Louisiana, United States, 70112
United States, Maine
Maine Medical Center
Scarborough, Maine, United States, 04074
United States, Maryland
MedStar Community Clinical Research Center
Hyattsville, Maryland, United States, 20782
United States, Massachusetts
Tufts Medical Center
Boston, Massachusetts, United States, 02111
United States, Minnesota
Health Partners Riverside Clinic
Minneapolis, Minnesota, United States, 55454
United States, Nebraska
Omaha VA Medical Center
Omaha, Nebraska, United States, 68105
University of Nebraska Medical Center
Omaha, Nebraska, United States, 68198
United States, New York
Beth Israel Medical Center
New York, New York, United States, 10003
United States, North Carolina
Duke University
Durham, North Carolina, United States, 27704
United States, Ohio
Cleveland Clinic
Cleveland, Ohio, United States, 44195
United States, Oregon
Kaiser Permanente Center for Health Research
Portland, Oregon, United States, 97227
United States, South Carolina
Medical University of South Carolina
Charleston, South Carolina, United States, 29425
United States, Tennessee
University of Tennessee Health Science Center
Memphis, Tennessee, United States, 38105
United States, Texas
University of Texas Southwestern Medical Center
Dallas, Texas, United States, 75390
Baylor College of Medicine
Houston, Texas, United States, 77030
Sponsors and Collaborators
Tufts Medical Center
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Office of Dietary Supplements (ODS)
Investigators
Principal Investigator: Anastassios Pittas, MD, MS Tufts Medical Center
  More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Tufts Medical Center
ClinicalTrials.gov Identifier: NCT01942694     History of Changes
Obsolete Identifiers: NCT02015052, NCT02239471
Other Study ID Numbers: U01DK098245 ( U.S. NIH Grant/Contract )
Study First Received: August 9, 2013
Last Updated: March 10, 2017

Keywords provided by Tufts Medical Center:
Prediabetes
Vitamin D

Additional relevant MeSH terms:
Diabetes Mellitus
Diabetes Mellitus, Type 2
Prediabetic State
Glucose Intolerance
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Hyperglycemia
Vitamins
Vitamin D
Ergocalciferols
Cholecalciferol
Micronutrients
Growth Substances
Physiological Effects of Drugs
Bone Density Conservation Agents

ClinicalTrials.gov processed this record on August 17, 2017