Vitamin D for Chemoprevention

Study Overview
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Brief Summary
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This study will help us know the effects of Vitamin D pills in Blacks. The results of this study may be the first step in creating ways to prevent the risks of colon and prostate cancer. It will also help us develop ways to reduce colon cancer and prostate cancer among Blacks. This study will find out if Vitamin D pills can increase Vitamin D to healthy levels in our bodies.

Detailed Description
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Participants will be asked to answer some questions about their diet, exercise and health. In addition, participants blood pressure will be taken. These assessments will occur at baseline, 3- and 6-month appointments. At baseline only, we will measure skin tone with a tool called the Photovolt 577. A small blood sample will be taken to see how much Vitamin D is the body and will also look at levels of other markers of disease such as proteins, hormones, and genes. Participants will take a vitamin pill every day for three months and be randomly assigned to one of four different types of pills. Participants will be called or visited at least every two weeks. They will be asked questions to determine if they have any side effects associated with high levels of Vitamin D. At the beginning of the second and third months, participants will be provided with more pills. At the end of the third month, another blood sample will be taken. Three months after that, the final blood sample will be taken.

Official Title
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Defining Optimal Doses of Vitamin D for Chemoprevention in Blacks.

Conditions
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Gastrointestinal Cancers, Prostate Cancer, Hypertension

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


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Between the ages of 30 and 80 years Comfortable communicating in English Currently has a primary care physician Willing to discontinue vitamin D or calcium supplements Willing to have all protocol specific tests run Exclusion Criteria: Plans on taking a vacation or travel to a sunny region within 3 months of vitamin supplementation period except for a short period (i.e. 1 weekend) Pregnant or breast feeding or planning on becoming pregnant in the following year Pre-existing calcium (including hypercalcemia), parathyroid conditions (including hyperparathyroidism), sarcoidosis No concurrent active malignancies (other than non-melanoma skin cancer) or previous diagnosis of prostate cancer Cognitively impaired Active thyroid disease (e.g. Graves, Hashimoto's or thyroiditis) History of nephrolithiasis, chronic liver disease, chronic renal disease, or renal dialysis

Ages Eligible for Study
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Minimum Age: 30 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 1<br>No Vitamin D | Dietary Supplement: Placebo<br>* Placebo pill taken once daily for 3 month<br>|
| Active Comparator: 2<br>1000 IU of Vitamin D | Drug: Vitamin D<br>* Taken orally every day for three months<br>|
| Active Comparator: 3<br>2000 IU of Vitamin D | Drug: Vitamin D<br>* Taken orally every day for three months<br>|
| Active Comparator: 4<br>4000 IU of Vitamin D | Drug: Vitamin D<br>* Taken orally every day for three months<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Levels of Plasma 25(OH)D at Baseline, 3 Months and 6 Months. | Among Blacks, identify a dose of oral vitamin D supplementation that will result in levels of plasma 25(OH)D that would be predicted to reduce colorectal cancer incidence. Community-based African Americans drawn from the Open Doors to Health, which is a colorectal cancer prevention study in 1554 subjects from 12 public-housing communities and community- and faith-based organizations in Boston. | Baseline, 3months, 6months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in IL-6 From 0 to 3 Months. | Examine the influence of oral vitamin D supplementation on inflammatory marker IL-6 from baseline to the 3 month follow-up. | From baseline to 3 months | 
| Change in IL-10 From 0 to 3 Months. | Examine the influence of oral vitamin D supplementation on inflammatory marker IL-10 from baseline to the 3 month follow-up. | From baseline to 3 months | 
| Change in sTNF-R2 From 0 to 3 Months. | Examine the influence of oral vitamin D supplementation on inflammatory marker sTNF-R2 from baseline to the 3 month follow-up. | From baseline to 3 months | 
| Change in CRP From 0 to 3 Months. | Examine the influence of oral vitamin D supplementation on inflammatory marker CRP from baseline to the 3 month follow-up. | From baseline to 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vitamin D, Blacks, cancer, hypertension