Ignite Creation Date:
2024-05-05 @ 11:20 AM
Last Modification Date:
2024-10-26 @ 9:04 AM
Study NCT ID:
NCT00005288
Status:
COMPLETED
Last Update Posted:
2017-01-16
First Post:
2000-05-25
Brief Title:
Epidemiology and Pulmonary Response To Organic Dust Exposure
Sponsor:
National Heart Lung and Blood Institute NHLBI
Organization:
National Heart Lung and Blood Institute NHLBI
Study Overview
Official Title:
None
Status:
COMPLETED
Status Verified Date:
2001-04
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
To characterize the nature of pulmonary responses to organic dust exposures in order to gain insight into patterns of respiratory disease in agricultural workers
Detailed Description:
BACKGROUND
In 1986 when the study began agriculture was one of the largest employers in the United States comprising nearly 12 million people Farm workers were hospitalized more frequently than other occupational groups and were found to have the highest number of restricted activity days due to injury and illness Much of this was due to frequent and disabling farm related accidents which made agriculture the most hazardous occupation in the United States Agricultural workers were also found to have high rates of respiratory disability compared with other industrial sectors based on Social Security disability records
The common denominator for respiratory disorders among agricultural workers was exposure to organic dust which was recognized to be a complex mixture of vegetable particles and fragments microorganisms and their products insects and insect fragments feed additives including fish meal and antibiotics and avian and rodent proteins While the vegetable dust itself was by far the most important exposure individual circumstances of growing storage and subsequent use of the product from which the organic dust arose influenced specific exposures In certain situations like animal confinement housing irritant gases including ammonia and hydrogen sulfide co-existed with an organic dust to further vary respiratory exposure
Workers exposed in Iowa swine production units were known to be significantly exposed to grain dust endotoxin animal danders and other proteins ammonia and hydrogen sulfide gas and a variety of microorganisms including fungi and thermophilic actinomycetes Cross-sectional epidemiological surveys had documented a high prevalence of respiratory symptoms including chronic cough phlegm and wheezing but also prominent constitutional symptoms including fever myalgias and malaise This study was one of several projects supported by a Specialized Center of Research in Occupational and Immunologic Lung Disease
Funding represents approximately 35 percent of the dollars of the Specialized Center of Research in Occupational and Immunologic Lung Disease P50HL37121 used to support epidemiologic studies
DESIGN NARRATIVE
A nested case-control study was carried out on a previously studied cohort Members of the cohort were resurveyed in the first year of the study All participants received a routine physical examination chest x-ray electrocardiogram if over 40 years of age routine laboratory tests methacholine challenge intradermal skin testing and bronchoalveolar lavage Cases for the swine confinement farmer cohort were selected if they had FEF50 of 60 percent or less of predicted for age sex height and race Three referents for each case were randomly selected from all swine confinement farmers not selected as cases non-confinement farmers and blue collar workers Measurements were repeated in the fourth year finishing in the fifth year of the study The study determined the extent to which epidemiological studies underestimated pulmonary responses and impairments among agricultural workers the environmental risk factors significantly related to cases whether atopy and heightened airway reactivity were significantly associated risk factors The subproject was not renewed in 1992
The study completion date listed in this record was obtained from the End Date entered in the old format Protocol Registration and Results System PRS
In 1986 when the study began agriculture was one of the largest employers in the United States comprising nearly 12 million people Farm workers were hospitalized more frequently than other occupational groups and were found to have the highest number of restricted activity days due to injury and illness Much of this was due to frequent and disabling farm related accidents which made agriculture the most hazardous occupation in the United States Agricultural workers were also found to have high rates of respiratory disability compared with other industrial sectors based on Social Security disability records
The common denominator for respiratory disorders among agricultural workers was exposure to organic dust which was recognized to be a complex mixture of vegetable particles and fragments microorganisms and their products insects and insect fragments feed additives including fish meal and antibiotics and avian and rodent proteins While the vegetable dust itself was by far the most important exposure individual circumstances of growing storage and subsequent use of the product from which the organic dust arose influenced specific exposures In certain situations like animal confinement housing irritant gases including ammonia and hydrogen sulfide co-existed with an organic dust to further vary respiratory exposure
Workers exposed in Iowa swine production units were known to be significantly exposed to grain dust endotoxin animal danders and other proteins ammonia and hydrogen sulfide gas and a variety of microorganisms including fungi and thermophilic actinomycetes Cross-sectional epidemiological surveys had documented a high prevalence of respiratory symptoms including chronic cough phlegm and wheezing but also prominent constitutional symptoms including fever myalgias and malaise This study was one of several projects supported by a Specialized Center of Research in Occupational and Immunologic Lung Disease
Funding represents approximately 35 percent of the dollars of the Specialized Center of Research in Occupational and Immunologic Lung Disease P50HL37121 used to support epidemiologic studies
DESIGN NARRATIVE
A nested case-control study was carried out on a previously studied cohort Members of the cohort were resurveyed in the first year of the study All participants received a routine physical examination chest x-ray electrocardiogram if over 40 years of age routine laboratory tests methacholine challenge intradermal skin testing and bronchoalveolar lavage Cases for the swine confinement farmer cohort were selected if they had FEF50 of 60 percent or less of predicted for age sex height and race Three referents for each case were randomly selected from all swine confinement farmers not selected as cases non-confinement farmers and blue collar workers Measurements were repeated in the fourth year finishing in the fifth year of the study The study determined the extent to which epidemiological studies underestimated pulmonary responses and impairments among agricultural workers the environmental risk factors significantly related to cases whether atopy and heightened airway reactivity were significantly associated risk factors The subproject was not renewed in 1992
The study completion date listed in this record was obtained from the End Date entered in the old format Protocol Registration and Results System PRS
Study Oversight
Has Oversight DMC:
Is a FDA Regulated Drug?:
Is a FDA Regulated Device?:
Is an Unapproved Device?:
Is a PPSD?:
Is a US Export?:
Is an FDA AA801 Violation?: