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Dietary and Genetic Factors in Asthma & Chronic Bronchitis in a Cohort of Chinese Singaporeans

This study has been completed.
Sponsor:
ClinicalTrials.gov Identifier:
NCT00342030
First Posted: June 21, 2006
Last Update Posted: July 2, 2017
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Information provided by:
National Institutes of Health Clinical Center (CC)
  Purpose

There is suggestive evidence for a role of dietary in the etiology of asthma and chronic bronchitis. However, there are few prospective data. We propose to expand our collaboration with the Singapore Chinese Health Study to examine dietary, environmental, and genetic factors, along with their interactions, in relation to the risk of developing asthma and chronic bronchitis. The Singapore Chinese Health Study is a cohort of 63,257 men and women of Chinese ethnicity in Singapore who were aged 45-74 years at enrollment from 1993 to 1998. Telephone follow-up of the cohort to update and outcome information began in 1999 and is ongoing. We expect to identify 538 cases of incident asthma and 672 cases of incident chronic bronchitis when the current follow-up questionnaire cycle is complete in 2004. In this proposal, we would validate self-reports of incident asthma, obtain follow-up data from the entire cohort to perform analyses of dietary and smoking in relation to these outcomes, and analyze genetic material on cases of incident asthma and chronic bronchitis and controls from the cohort. In this proposal we will examine the following hypotheses:

  1. Higher intake of fruits and/or antioxidant micronutrients decreases the risk of developing asthma and chronic bronchitis.

    a. Effects if fruit and/or antioxidant micronutrients may differ by smoking history.

  2. Common polymorphisms in genes involved in the response to oxidative stress influence the risk of asthma and chronic Bronchitis. We initially propose to examine polymorphisms in three genes--glutathione S-tranferase M1, glutahione S-transferase P1, and matrix metalloproteinase-1. However, we plan to examine additional relevant polymorphisms in the future, especially taking advantage of high throughput screens of candidate genes for asthma and chronic bronchitis. It is possible that by 2004 when the sample set will be available that more compelling candidates and high throughput screens may be available to us at a low cost. Thus we will re-evaluate our choice when the samples are available.
  3. Polymorphisms in these and other genes interact with fruit/antioxidant intake and/or smoking to influence the risk of asthma and chronic bronchitis.

Condition
Chronic Bronchitis Asthma

Study Type: Observational
Official Title: Dietary and Genetic Factors in Asthma & Chronic Bronchitis in a Cohort of Chinese Singaporeans

Resource links provided by NLM:


Further study details as provided by National Institutes of Health Clinical Center (CC):

Estimated Enrollment: 63257
Study Start Date: November 1, 2002
Estimated Study Completion Date: April 12, 2012
Detailed Description:

There is suggestive evidence for a role of diet in the etiology of asthma and chronic bronchitis. However, there are few prospective data. We propose to expand our collaboration with the Singapore Chinese Health Study to examine dietary, environmental, and genetic factors, along with their interactions, in relation to the risk of developing asthma and chronic bronchitis. The Singapore Chinese Health Study (NIH grant CA080205) is a cohort of 63,257 men and women of Chinese ethnicity in Singapore who were aged 45-74 years at enrollment from 1993 to 1998. Telephone follow-up of the cohort to update and outcome information began in 1999 and is ongoing. We expect to identify 538 cases of incident asthma and 672 cases of incident chronic bronchitis when the current follow-up questionnaire cycle is complete in 2004. In this proposal, we would validate self-reports of incident asthma, obtain follow-up data from the entire cohort to perform analyses of diet and smoking in relation to these outcomes, and analyze genetic material on cases of incident asthma and chronic bronchitis and controls from the cohort. In this proposal we will examine the following hypotheses:

  1. Higher intake of fruits and/or antioxidant micronutrients decreases the risk of developing asthma and chronic bronchitis.

    a. Effects of fruit and/or antioxidant micronutrients may differ by smoking history

  2. Common polymorphisms in genes involved in the response to oxidative stress influence the risk of asthma and chronic bronchitis. We initially propose to examine polymorphisms in three genes -- glutathione S-tranferase M1, glutathione S-transferase P1, and matrix metalloproteinase-1. However, we plan to examine additional relevant polymorphisms in the future, especially taking advantage of high throughput screens of candidate genes for asthma and chronic bronchitis. It is possible that by 2004 when the sample set will be available that more compelling candidates and high throughput screens may be available to us at a low cost. Thus we will re-evaluate our choice when the samples are available.
  3. Polymorphisms in these and other genes interact with fruit/antioxidant intake and/or smoking to influence the risk of asthma and chronic bronchitis.
  Eligibility

Information from the National Library of Medicine

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Ages Eligible for Study:   45 Years to 74 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria
  • INCLUSION CRITERIA:

No new subjects are being enrolled for this proposal.

Subjects are the 63,257 participants in the Singapore Chinese Health Study. That study includes men and women aged 45-74 at enrollment of Chinese ethnicity living in Singapore.

  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00342030


Locations
Singapore
National University of Singapore
Kent Ridge, Singapore, 27709
Sponsors and Collaborators
National Institute of Environmental Health Sciences (NIEHS)
Investigators
Principal Investigator: Frederick W Miller, M.D. National Institute of Environmental Health Sciences (NIEHS)
  More Information

Publications:
ClinicalTrials.gov Identifier: NCT00342030     History of Changes
Other Study ID Numbers: 999903044
03-E-N044
First Submitted: June 19, 2006
First Posted: June 21, 2006
Last Update Posted: July 2, 2017
Last Verified: April 12, 2012

Keywords provided by National Institutes of Health Clinical Center (CC):
Respiratory
Polymorphism
Fruit
COPD
Prospective
Diet

Additional relevant MeSH terms:
Asthma
Bronchitis
Acute Disease
Bronchitis, Chronic
Bronchial Diseases
Respiratory Tract Diseases
Lung Diseases, Obstructive
Lung Diseases
Respiratory Hypersensitivity
Hypersensitivity, Immediate
Hypersensitivity
Immune System Diseases
Respiratory Tract Infections
Disease Attributes
Pathologic Processes
Pulmonary Disease, Chronic Obstructive