Study of Calcium Plus Vitamin D Supplementation in Prevention of Colorectal Adenomas Recurrence

Study Overview
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Brief Summary
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Calcium plus vitamin D may be effective in the prevention of colorectal adenoma recurrence. The aim of this study is to investigate the effect of supplementation with calcium plus vitamin D on the recurrence of colorectal adenomas.

Detailed Description
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Colorectal adenomas are well-known to be precancerous lesions that develop into colorectal cancers on the basis of the adenoma-carcinoma sequence. The effects of screening for colorectal adenomas and removing precancerous lesions on the prevention of colorectal cancer have been established. Because of the high recurrence rates of colorectal adenomas in patients who have undergone polypectomy, the potential chemopreventive agents that may reduce the risk of colorectal adenoma recurrence need to be investigated. Since laboratory and epidemiologic evidence suggests that calcium or vitamin D may help prevent colorectal adenomas, we conduct a randomized, placebo-controlled, prospective clinical trial to study the effect and safety of calcium plus vitamin D supplementation in prevention of colorectal adenomas recurrence.

Official Title
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Calcium Plus Vitamin D Supplementation in Prevention of Colorectal Adenomas Recurrence:a Prospective, Randomized, Placebo-controlled, Multicenter Clinical Trial

Conditions
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Colorectal Adenoma

Intervention / Treatment
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* Drug: Ca plus vit D


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Individuals aged 18-65years Individuals who had at least one histologically confirmed colorectal adenoma removed within three months before recruitment Individuals without a history of familial polyposis Those who voluntarily sign the consent form after being fully informed and understanding the purpose and procedures of the study , characters of the disease, effect of medications, methods of related examinations, and potential risk/benefits of the study Exclusion Criteria: Patients who are hypersensitive or intolerant to the drugs Patients who are intolerant to another colonoscopy examination Patients with hypercalcemia or urolithiasis Pregnant women, women during breast-feeding period, or women with expect pregnancy Patients with diabetes mellitus, severe heart or renal disease, or cancer history Patients with a history of subtotal gastrectomy or partial bowel resection Patients who are not able to cooperate Individual who are involved in designing, planning or performing this clinical trial Patients with medical conditions who are not appropriate to participate the study Patients who are taking aspirin, NSAIDs or COX2 inhibitors Patients who are taking folic acid or Butyrate. Patients with IBD

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Factorial Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Ca plus vit D<br>elemental calcium 1200mg/d plus vitamin D3 250 IU/d daily supplements for 3 years | Drug: Ca plus vit D<br>* elemental calcium 1200mg/d plus vitamin D3 250 IU/d daily supplements<br>* Other names: Caltrate;|
| Placebo Comparator: placebo<br>identical-appearing placebo supplements for 3 years | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The primary objective of this study is to investigate recurrence rates of colorectal adenoma (CRA) after calcium plus vitamin D intervention. |  | 3 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The recurrence rates of advanced colorectal adenoma (A-CRA) after calcium plus vitamin D intervention. |  | 3 years |