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

• ClinicalTrials.gov Identifier: NCT00342030
• Recruitment Status: Completed
• First Posted: June 21, 2006
• Last Update Posted: July 2, 2017
• Sponsor: National Institute of Environmental Health Sciences (NIEHS)
• Information provided by: National Institutes of Health Clinical Center (CC)

Study Description

Brief Summary:

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 or disease
Chronic Bronchitis; Asthma

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.

Study Design

• Study Type: Observational
• Estimated Enrollment: 63257 participants
• Official Title: Dietary and Genetic Factors in Asthma & Chronic Bronchitis in a Cohort of Chinese Singaporeans
• Study Start Date: November 1, 2002
• Study Completion Date: April 12, 2012

Groups and Cohorts

Outcome Measures

Eligibility Criteria

• Ages Eligible for Study: 45 Years to 74 Years (Adult, Older Adult)
• 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

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:

Buist AS, Vollmer WM. Reflections on the rise in asthma morbidity and mortality. JAMA. 1990 Oct 3;264(13):1719-20.

Ng TP, Hui KP, Tan WC. Prevalence of asthma and risk factors among Chinese, Malay, and Indian adults in Singapore. Thorax. 1994 Apr;49(4):347-51.

Karjalainen A, Kurppa K, Martikainen R, Klaukka T, Karjalainen J. Work is related to a substantial portion of adult-onset asthma incidence in the Finnish population. Am J Respir Crit Care Med. 2001 Aug 15;164(4):565-8.

• ClinicalTrials.gov Identifier: NCT00342030
• Other Study ID Numbers: 999903044; 03-E-N044
• 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; Bronchitis, Chronic; Acute Disease; 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