Study of Folic Acid, Calcium and Vitamin D in Preventing Colorectal Polyps and Colorectal Cancer

Study Overview
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Brief Summary
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Folic acid (FA) and its derivatives (folate) which play a role in nucleotide synthesis and methylation reactions as well as calcium and vitamin D are assumed to be effective in the prevention of colorectal polyps and Colorectal cancer (CRC). The aim of this study is to investigate the roles of FA as well as calcium and vitamin D in the prevention of CRC.

Detailed Description
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Colorectal cancer (CRC) affects approximately one million people each year with a five-year survival rate of 62% . Considerable interest has recently been focused on the relationship between the chemoprevention of colorectal polyps/CRA and CRC. Therefore, the use of nutritional compounds which are usually less afflicted with the risk of severe side effects for colorectal adenoma (CRA) prevention and health maintenance is an emerging field.

Official Title
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A Randomize Controlled Trial of Folic Acid, Calcium and Vitamin D in Preventing Colorectal Polyps and Colorectal Cancer

Conditions
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Colorectal Neoplasms

Intervention / Treatment
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* Drug: folic acid
* Drug: folic acid calcium vitamin D3
* Drug: calcium


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: individuals aged 50-80 years Patients had undergone complete colonoscopy with no adenoma found 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 Pregnant women, woman during breast-feeding period, or women with expect pregnancy Patients with diabetes mellitus, severe heart or renal disease，or cancer history Patients with malignant neoplasm, or suspicious colorectal cancer Patients who are not able to cooperate Individuals who are involved in designing, planning or performing this experiment Patients with medical conditions who are not appropriate to participate the study Patients who are take aspirin or cyclooxygenase 2 inhibitor （COX2）.

Ages Eligible for Study
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Minimum Age: 50 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: Factorial Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: FA<br>Patients receive oral folic acid pill 1 mg daily for 36 months in the absence of unacceptable toxicity or any other adverse effects (FA Arm). | Drug: folic acid<br>* Patients receive oral folic acid 1mg daily for 36 months in the absence of unacceptable toxicity or any other adverse effects.<br>|
| Experimental: FA+Ca<br>Patients receive oral folic acid pill 1 mg+ calcium 1200mg +vitamin D3 250 IU daily for 36 months in the absence of unacceptable toxicity or any other adverse effects(FA+Ca arm). | Drug: folic acid calcium vitamin D3<br>* Patients receive oral folic acid 1mg + calcium 1200mg +vitamin D3 250 IU daily for 36 months in the absence of unacceptable toxicity or any other adverse effects .<br>|
| Experimental: Ca<br>Patients receive oral calcium 1200mg +vitamin D3 250 IU daily for 36 months in the absence of unacceptable toxicity or any other adverse effects (Ca Arm). | Drug: calcium<br>* calcium 1200mg/d + vitamin D3 250 IU/d daily supplements<br>|
| Placebo Comparator: blank control group<br>Patients receive oral placebo once daily for 36 months in the absence of unacceptable toxicity or any other adverse effects. | |

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 the incidence of colorectal adenoma (CRA) after Folic acid, calcium and vitamin D intervention. |  | baseline and 3 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the incidence of advanced colorectal adenoma (A-CRA) after Folic acid, calcium and vitamin D intervention. |  | baseline and 3 years | 
| changes in serum calcium |  | baseline and 3 years | 
| changes in serum FA |  | baseline and 3 years | 
| the incidence of colorectal cancer (CRC) after Folic acid, calcium and vitamin D intervention. |  | baseline and 3 years | 
| changes in clinical symptoms scores (positive immunochemical fecal occult blood test (iFOBT), diarrhea, or constipation et al) |  | baseline and 3 years | 
| differences in Histological types of CRA OR CRC |  | baseline and 3 years |