Trial record 1 of 1 for:    NCT01942694
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Vitamin D and Type 2 Diabetes Study (D2d)

This study is currently recruiting participants. (see Contacts and Locations)
Verified September 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: September 22, 2014
Last verified: September 2014

August 9, 2013
September 22, 2014
October 2013
November 2017   (final data collection date for primary outcome measure)
Time to development of diabetes [ Time Frame: Every 12 months for approximately 48 months ] [ Designated as safety issue: No ]
Same as current
Complete list of historical versions of study NCT01942694 on ClinicalTrials.gov Archive Site
  • 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 ]
Same as current
Not Provided
Not Provided
 
Vitamin D and Type 2 Diabetes Study
Vitamin D and Type 2 Diabetes Study

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.

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.

Interventional
Not Provided
Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
  • Prediabetes
  • Type 2 Diabetes
  • Dietary Supplement: Vitamin D (Cholecalciferol)
    Vitamin D (Cholecalciferol) 4000 IU, administered as 1 soft-gel pill daily by mouth.
  • Other: Placebo
    Administered as one soft-gel pill daily by mouth
  • Placebo Comparator: Placebo
    One pill daily
    Intervention: Other: Placebo
  • Active Comparator: Vitamin D (Cholecalciferol)
    One vitamin D pill daily
    Intervention: Dietary Supplement: Vitamin D (Cholecalciferol)
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruiting
2382
December 2017
November 2017   (final data collection date for primary outcome measure)

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.
Both
30 Years and older
No
United States
 
NCT01942694
U01DK098245, U01DK098245
Yes
Tufts Medical Center
Tufts Medical Center
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Principal Investigator: Anastassios Pittas, MD, MS Tufts Medical Center
Tufts Medical Center
September 2014

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP