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Vitamin D and Type 2 Diabetes Study (D2d)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT01942694
Recruitment Status : Active, not recruiting
First Posted : September 16, 2013
Results First Posted : September 9, 2020
Last Update Posted : September 9, 2020
Sponsor:
Collaborators:
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Office of Dietary Supplements (ODS)
American Diabetes Association
Information provided by (Responsible Party):
Tufts Medical Center

Brief Summary:
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 or disease Intervention/treatment Phase
Prediabetes Type 2 Diabetes Dietary Supplement: Vitamin D (Cholecalciferol) Other: Placebo Not Applicable

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 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.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 2423 participants
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
Study Start Date : October 2013
Actual Primary Completion Date : November 2018
Estimated Study Completion Date : May 2021

Resource links provided by the National Library of Medicine


Arm Intervention/treatment
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.




Primary Outcome Measures :
  1. Time to Development of Diabetes [ Time Frame: Approximately 48 months ]
    New-onset diabetes was based on annual glycemic testing of fasting plasma glucose, glycated hemoglobin, and 2-hour post-load plasma glucose and semiannual testing of fasting plasma glucose and glycated hemoglobin. If two or three of the glycemic measures met the 2010 ADA thresholds for diabetes, the participant was considered to have met the diabetes outcome. When only the measure for fasting plasma glucose or glycated hemoglobin met the threshold, confirmatory testing was performed for the positive measure within 8 weeks. If only the measure for 2-hour post-load plasma glucose met the threshold, then a 75-g oral glucose tolerance test to reassess all three glycemic measures was repeated. If the repeat measure was positive or both fasting plasma glucose and glycated hemoglobin were positive (in the case of a repeat oral glucose tolerance test), than the participant was considered to have met the diabetes outcome.


Secondary Outcome Measures :
  1. Variability of Response to Vitamin D Supplementation by Baseline Characteristic: 25OHD Concentration [ Time Frame: Approximately 48 months ]
  2. Variability of Response to Vitamin D Supplementation by Baseline Characteristic: Race (as a Proxy for Skin Pigmentation) [ Time Frame: Approximately 48 months ]
    Race and ethnic group were reporting by the participant. The category "other" includes American Indian or Alaska Native; Native Hawaiian or other Pacific Islander; and other race. Ethnic group includes any race.

  3. Variability of Response to Vitamin D Supplementation by Baseline Characteristic: Pre-diabetes Criteria (Two vs. Three Criteria) [ Time Frame: Approximately 48 months ]
    Participants met at least two of three glycemic criteria for prediabetes: fasting plasma glucose level, 100 to 125 mg per deciliter (5.6 to 6.9 mmol per liter); plasma glucose level 2 hours after a 75-g oral glucose load, 140 to 199 mg per deciliter (7.8 to 11.0 mmol per liter) (impaired glucose tolerance); and glycated hemoglobin level, 5.7 to 6.4% (39 to 47 mmol per mole).

  4. Variability of Response to Vitamin D Supplementation by Baseline Characteristic: BMI [ Time Frame: Approximately 48 months ]
  5. Variability of Response to Vitamin D Supplementation by Baseline Characteristic: Waist Circumference [ Time Frame: Approximately 48 months ]
  6. Variability of Response to Vitamin D Supplementation by Baseline Characteristic: Age [ Time Frame: Approximately 48 months ]
  7. Variability of Response to Vitamin D Supplementation by Baseline Characteristic: Geographic Location (as a Proxy for Sun Exposure) [ Time Frame: Approximately 48 months ]
  8. Variability of Response to Vitamin D Supplementation by Baseline Characteristic: Calcium Intake From Supplements [ Time Frame: Approximately 48 months ]
  9. Blood Plasma 25OHD Concentration. [ Time Frame: Approximately 48 months ]
  10. Number of Participants With Adverse Events. [ Time Frame: Approximately 48 months ]
  11. Change in Blood Pressure as a Continuous Variable. [ Time Frame: Approximately 48 months ]
  12. Number of Participants Who Discontinue Study Pills. [ Time Frame: Approximately 48 months ]
  13. Change in FPG as a Continuous Variable. [ Time Frame: Every 12 months for approximately 48 months ]
  14. Change in 2hPG as a Continuous Variable. [ Time Frame: Every 12 months for approximately 48 months. ]
  15. Change in HbA1c as a Continuous Variable. [ Time Frame: Every 6 months for approximately 48 months ]
  16. Measurement of Insulin Resistance (Derived From the OGTT). [ Time Frame: Every 12 months for approximately 48 months ]
  17. Measurement of Beta Cell Secretion (Derived From the OGTT) [ Time Frame: Every 12 months for approximately 48 months ]
  18. Identification of Characteristics Associated With the Variability in Achieved 25OHD Concentration. [ Time Frame: Every 12 months for approximately 48 months ]

Other Outcome Measures:
  1. Variability of Response to Vitamin D Supplementation by Baseline Characteristic: Sex [ Time Frame: Approximately 48 months. ]
  2. Variability of Response to Vitamin D Supplementation by Baseline Characteristic: Ethnicity [ Time Frame: Approximately 48 months. ]
  3. Variability of Response to Vitamin D Supplementation by Baseline Characteristic: 2 Hour Plasma Glucose [ Time Frame: Approximately 48 months ]
  4. Time to Development of Cancer. [ Time Frame: Approximately 48 months. ]
  5. Time to Development of Cardiovascular Event. [ Time Frame: Approximately 48 months. ]
  6. Incidence of Cancer in a Pre-diabetes Population Defined by the Modern American Diabetes Association Criteria. [ Time Frame: Approximately 48 months. ]
  7. Incidence of Cardiovascular Disease in a Pre-diabetes Population Defined by the Modern American Diabetes Association Criteria. [ Time Frame: Approximately 48 months. ]
  8. Quality of Life and Mood Scores in Pre-diabetes Population Using a Validated Instrument (PROMIS-29 Profile v2.0 and a General Question on Perception of Overall Health From the PROMIS Scale 1.2). [ Time Frame: One time assessment at the month 24 visit. ]


Information from the National Library of Medicine

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Ages Eligible for Study:   30 Years and older   (Adult, Older Adult)
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 ≥ 24.0 (22.5 for Asians) and ≤ 42.0 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.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01942694


Locations
Show Show 25 study locations
Sponsors and Collaborators
Tufts Medical Center
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Office of Dietary Supplements (ODS)
American Diabetes Association
Investigators
Layout table for investigator information
Principal Investigator: Anastassios Pittas, MD, MS Tufts Medical Center
  Study Documents (Full-Text)

Documents provided by Tufts Medical Center:
Study Protocol  [PDF] July 11, 2017
Statistical Analysis Plan  [PDF] March 20, 2018

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):

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Responsible Party: Tufts Medical Center
ClinicalTrials.gov Identifier: NCT01942694    
Obsolete Identifiers: NCT02015052, NCT02239471
Other Study ID Numbers: U01DK098245 ( U.S. NIH Grant/Contract )
U01DK098245 ( U.S. NIH Grant/Contract )
First Posted: September 16, 2013    Key Record Dates
Results First Posted: September 9, 2020
Last Update Posted: September 9, 2020
Last Verified: August 2020
Keywords provided by Tufts Medical Center:
Prediabetes
Vitamin D
Additional relevant MeSH terms:
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Diabetes Mellitus
Diabetes Mellitus, Type 2
Prediabetic State
Glucose Intolerance
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Hyperglycemia
Vitamin D
Cholecalciferol
Vitamins
Micronutrients
Nutrients
Growth Substances
Physiological Effects of Drugs
Bone Density Conservation Agents
Calcium-Regulating Hormones and Agents