Vitamin D and Type 2 Diabetes Study (D2d)

This study is currently recruiting participants. (see Contacts and Locations)
Verified June 2014 by Tufts Medical Center
Sponsor:
Collaborator:
Information provided by (Responsible Party):
Tufts Medical Center
ClinicalTrials.gov Identifier:
NCT01942694
First received: August 9, 2013
Last updated: June 17, 2014
Last verified: June 2014
  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
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, 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 ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Measurement of plasma 25OHD concentration. [ Time Frame: Every 12 months for approximately 48 months ] [ Designated as safety issue: No ]
  • 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 ] [ Designated as safety issue: Yes ]
  • Blood Pressure [ Time Frame: Every 6 months for approximately 48 months ] [ Designated as safety issue: No ]
  • Variability of response to vitamin D supplementation by baseline characteristic: BMI [ Time Frame: Every 12 months for approximately 48 months ] [ Designated as safety issue: No ]
  • Variability of response to vitamin D supplementation by baseline characteristic: waist circumference [ Time Frame: Every 12 months for approximately 48 months ] [ Designated as safety issue: No ]
  • Variability of response to vitamin D supplementation by baseline characteristic: age [ Time Frame: Every 12 months for approximately 48 months ] [ Designated as safety issue: No ]
  • 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 ] [ Designated as safety issue: No ]
  • Variability of response to vitamin D supplementation by baseline characteristic: calcium intake [ Time Frame: every 12 months for approximately 48 months ] [ Designated as safety issue: No ]
  • Variability of response to vitamin D supplementation by baseline characteristic: 25OHD concentration [ Time Frame: Every 12 months for approximately 48 months ] [ Designated as safety issue: No ]
  • 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 ] [ Designated as safety issue: No ]
  • 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. ] [ Designated as safety issue: Yes ]
  • Change in FPG as a continuous variable. [ Time Frame: Every 6 months for approximately 48 months ] [ Designated as safety issue: No ]
  • Change in 2hPG as a continuous variable. [ Time Frame: Every 12 months for approximately 48 months. ] [ Designated as safety issue: No ]
  • Measurement of insulin resistance (derived from the OGTT). [ Time Frame: Every 12 months for approximately 48 months ] [ Designated as safety issue: No ]
  • Measurement of beta cell secretion (derived from the OGTT) [ Time Frame: Every 12 months for approximately 48 months ] [ Designated as safety issue: Yes ]
  • Identification of characteristics associated with the variability in achieved 25-hydroxycholecalciferol (25OHD) concentration. [ Time Frame: Every 12 months for approximately 48 months ] [ Designated as safety issue: No ]
  • Change in HbA1c as a continuous variable. [ Time Frame: Every 6 months for approximately 48 months ] [ Designated as safety issue: No ]

Estimated Enrollment: 2382
Study Start Date: October 2013
Estimated Study Completion Date: December 2017
Estimated Primary Completion Date: November 2017 (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 4 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
Genders Eligible for Study:   Both
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

  Show 21 Study Locations
Sponsors and Collaborators
Tufts Medical Center
Investigators
Principal Investigator: Anastassios Pittas, MD, MS Tufts Medical Center
  More Information

No publications provided

Responsible Party: Tufts Medical Center
ClinicalTrials.gov Identifier: NCT01942694     History of Changes
Other Study ID Numbers: U01DK098245, U01DK098245
Study First Received: August 9, 2013
Last Updated: June 17, 2014
Health Authority: United States: Federal Government

Keywords provided by Tufts Medical Center:
Prediabetes
Vitamin D

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

ClinicalTrials.gov processed this record on August 28, 2014