- ICH GCP
- US Clinical Trials Registry
- Clinical Trial NCT00606957
The Effect of Vitamin D Repletion on Insulin Resistance
The reason for doing this study is to learn whether raising a person's vitamin D level from below normal to normal levels will improve his or her body's ability to use sugar. Vitamin D is well known to be an important vitamin for the development and maintenance of bones. Recently, scientists have learned that vitamin D may have a role in the prevention of cancer, diabetes, and autoimmune diseases. The investigators are specifically interested in studying this question in the overweight/obese population as they are at greater risk for both vitamin D deficiency and impaired ability to metabolize sugar (glucose intolerance).
Primary Hypotheses:
Vitamin D repletion (increasing the serum 25(OH)D level from ≤ 20 ng/ml to ≥ 30 ng/ml) will improve insulin sensitivity in individuals who are overweight/obese and insulin resistant.
Secondary Hypotheses:
1.Vitamin D repletion will improve biomarkers of cardiovascular risk and inflammation (directly altering macrophage cytokine production and/or indirectly as a result of improvement in insulin sensitivity.) 2.30,000 IU (0.25 mg) weekly of cholecalciferol (vitamin D3) will raise serum 25(OH)D levels from ≤ 20 ng/ml to ≥ 30 ng/ml overweight/obese population.
Study Overview
Status
Conditions
Intervention / Treatment
Study Type
Enrollment (Anticipated)
Phase
- Not Applicable
Contacts and Locations
Study Locations
-
-
New York
-
New York, New York, United States, 10021
- Rockefeller University
-
-
Participation Criteria
Eligibility Criteria
Ages Eligible for Study
Accepts Healthy Volunteers
Genders Eligible for Study
Description
Inclusion Criteria:
- Nonsmoking men and women, ages 18-65
- Body mass index (BMI) ≥ 28 kg/m² and within 10% of maximum weight
- Serum 25(OH)D level ≤ 20 ng/ml
- Serum insulin level ≥ 7.2 mU/l
- Willingness to maintain current body weight for the duration of the study
- Willingness to maintain baseline lifestyle activities and routines for the duration of the study
- Willingness to avoid the use of non-steroidal anti-inflammatory drugs (NSAIDS), including low-dose daily aspirin, for at least ten days prior to each admission (due to the potential effects of these agents on inflammatory markers.)
- Willingness to avoid the use of all over-the-counter or prescription vitamins, dietary supplements, and herbal products during the study, with the exception of a basic multivitamin supplement.
- If of childbearing potential, willingness to use highly effective contraception for the duration of the study.
Exclusion Criteria:
- Current tobacco smoking
- History of bleeding or coagulation disorders
- Gastrointestinal disease resulting in significant gastrointestinal dysfunction or malabsorption
- History of diabetes, or diagnosed during screening OGTT
- Current treatment with hypertensive medications
- History of cardiovascular disease
- Renal disease, as evidenced by a serum creatinine above the upper limit of normal on more than one screening visit
- History of kidney stones
- History of chronic hepatitis, or liver enzymes (AST or ALT) more than 2.5 times the upper limit of normal
- Primary hyperparathyroidism or baseline hypercalcemia from any cause
- Current treatment with over-the-counter or prescription weight loss medications, such as orlistat or sibutramine
- History of bariatric surgery
- Current treatment with any cholesterol-lowering medications, such as statins, niacin, fibrates, or ezetimibe
- Blood pressure ≥ 145/90 after ten minutes of rest on more than one screen visit
- Hyperthyroidism or untreated hypothyroidism. Subjects with chronic, treated, stable hypothyroidism may be included in the study at the discretion of the Principal Investigator.
- Pregnancy, desired pregnancy, or lactation within the study period.
- HIV, Hepatitis B and C
- Medical conditions requiring daily calcium supplementation or antacid use
- Use of medications known to interact with calcium or vitamin D metabolism (bisphosphonates, corticosteroids, thiazide diuretics, cholestyramine, colestipol, mineral oil, phenytoin, barbituates, dititalis glycosides, antacids)
- Subjects with known hypersensitivity to cholecalciferol
- Participation in an investigational drug study within one month of screening
- History, physical, or laboratory findings suggestive of any other medical or psychological condition that would, in the opinion of the principal investigator, make the candidate ineligible for the study
Study Plan
How is the study designed?
Design Details
- Primary Purpose: Treatment
- Allocation: N/A
- Interventional Model: Single Group Assignment
- Masking: None (Open Label)
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Time Frame |
---|---|
The primary outcome is change in insulin sensitivity over time, as measured by the glucose clamp, HOMA and OGTT.
Time Frame: 14 weeks
|
14 weeks
|
Collaborators and Investigators
Sponsor
Investigators
- Principal Investigator: Allegra Grossman, MD, The Rockefeller University
Study record dates
Study Major Dates
Study Start
Primary Completion (Actual)
Study Completion (Actual)
Study Registration Dates
First Submitted
First Submitted That Met QC Criteria
First Posted (Estimate)
Study Record Updates
Last Update Posted (Estimate)
Last Update Submitted That Met QC Criteria
Last Verified
More Information
Terms related to this study
Keywords
Additional Relevant MeSH Terms
Other Study ID Numbers
- RUH IRB# AGR-0623
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.
Clinical Trials on Obesity
-
Central Hospital, Nancy, FranceNot yet recruiting
-
University of MinnesotaNational Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)Active, not recruitingAdolescent ObesityUnited States
-
Helsinki University Central HospitalKarolinska Institutet; Folkhälsan Researech CenterEnrolling by invitation
-
Istanbul Medipol University HospitalMedipol UniversityCompletedObesity, Morbid | Obesity, Adolescent | Obesity, Abdominal | Weight, Body | Obesity, VisceralTurkey
-
Queen Fabiola Children's University HospitalNot yet recruitingMorbid Obesity | Adolescent Obesity | Bariatric SurgeryBelgium
-
Washington University School of MedicinePatient-Centered Outcomes Research Institute; Pennington Biomedical Research... and other collaboratorsActive, not recruitingOvernutrition | Nutrition Disorders | Overweight | Body Weight | Pediatric Obesity | Body Weight Changes | Childhood Obesity | Weight Gain | Adolescent Obesity | Obesity, Childhood | Overweight and Obesity | Overweight or Obesity | Overweight AdolescentsUnited States
-
Azienda Ospedaliero-Universitaria Consorziale Policlinico...Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies; Istituti... and other collaboratorsCompletedMorbid Obesity | Metabolically Healthy ObesityItaly
-
The Hospital for Sick ChildrenCompleted
-
Ihuoma EneliCompletedObesity, ChildhoodUnited States
-
Fundació Sant Joan de DéuRecruitingObesity, Childhood | Obesity, AdolescentSpain
Clinical Trials on Vitamin D3 (cholecalciferol)
-
Medical University of South CarolinaThrasher Research FundCompletedVitamin D Deficiency | PregnancyUnited States
-
Medical University of South CarolinaEunice Kennedy Shriver National Institute of Child Health and Human Development... and other collaboratorsCompleted
-
Mahidol UniversityUnknownCritical Illness | Vitamin D Deficiency | SarcopeniaThailand
-
Brigham and Women's HospitalNational Heart, Lung, and Blood Institute (NHLBI)Active, not recruiting
-
Medical University of South CarolinaEunice Kennedy Shriver National Institute of Child Health and Human Development...Completed
-
University of California, San FranciscoCompletedUlcerative Colitis (UC) | Crohn's Disease (CD)United States
-
National Institute of Allergy and Infectious Diseases...Autoimmunity Centers of ExcellenceTerminatedSystemic Lupus ErythematosusUnited States
-
Sanjay Gandhi Postgraduate Institute of Medical...CompletedPancreatitis, ChronicIndia
-
Atlanta VA Medical CenterCompletedVitamin D Deficiency | Chronic Kidney DiseaseUnited States
-
University of California, San FranciscoCompleted