Individualized Response to Vitamin D Treatment Study

Study Overview
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Brief Summary
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The goal of this clinical trial is to determine individual-level genetic and metabolic characteristics that modify the response to cholecalciferol treatment. This study is double blind, parallel design, randomized clinical trial that will assess genetic and metabolic characteristics that modify the response to cholecalciferol treatment. . Eligible participants will be randomly assigned to receive cholecalciferol treatment (2,000 international units of cholecalciferol daily by mouth) or placebo in a 3:1 ratio for a total duration of 16-weeks. The planned sample size is 1,600. The primary aim of this study is to identify genetic polymorphisms, clinical characteristics, and biomarkers that modify the biologic response to vitamin D3 treatment, assessed by changes in serum concentrations of parathyroid hormone (PTH) and 1,25(OH)2D and urine calcium excretion.

Official Title
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Multi Ethnic Study of Atherosclerosis Individualized Response to Vitamin D Treatment Study

Conditions
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Characteristics That Modify the Response to Cholecalciferol Treatment

Intervention / Treatment
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* Dietary Supplement: Vitamin D3
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1,600 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) study who are returning for their scheduled 6th MESA study visit. Participants will be recruited from four field centers: Wake Forest University, Winston-Salem, NC; Columbia University, New York, NY; Northwestern University, Evanston, IL; and Johns Hopkins University, Baltimore, MD. Exclusion Criteria: Current use of >1,000 international units (IU) of cholecalciferol daily Current use of any activated vitamin D product (calcitriol, paricalcitol, hectorol) Known history of allergy or adverse reaction to vitamin D treatment Known clinical history of primary hyperparathyroidism Known clinical history of kidney stones within the previous 5 years Current participation in another interventional study Inability to provide written informed consent

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Active Treatment<br> | Dietary Supplement: Vitamin D3<br>* cholecalciferol (vitamin D3) 2000 IU capsules daily<br>|
| Placebo Comparator: Placebo<br>Placebo | Drug: Placebo<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Serum 1,25(OH)2D Concentration |  | 16 weeks | 
| Change in Serum PTH Concentration |  | 16 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Systolic Blood Pressure |  | 16 weeks | 
| Change in Urine Calcium Excretion | Urine calcium excretion estimated as spot urine calcium-creatinine ratio | 16 weeks | 
| Change in Serum Calcium Concentrations |  | 16 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vitamin D, cardiovascular disease, MESA, genetics, pharmacogenetics, blood pressure, biomarkers