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Agriculture Health Study

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ClinicalTrials.gov Identifier: NCT00352924
Recruitment Status : Active, not recruiting
First Posted : July 17, 2006
Last Update Posted : January 10, 2018
Information provided by (Responsible Party):

Study Description
Brief Summary:

The "Agricultural Health Study" (AHS) is a collaborative effort between the National Cancer Institute and the National Institute of Environmental Health Sciences. The U.S. Environmental Protection Agency and the National Institute for Occupational Safety and Health are providing support for a limited exposure assessment effort.

Initial data collection on a prospective cohort of 89,658 study subjects has been completed as of December 1997. Participants completed questionnaires that included items on pesticides used, other agricultural exposures, and work practices that modify exposure as well as on other activities that may affect either exposure or disease risks (e.g., diet, exercise, alcohol consumption, medical conditions, family history of cancer, other occupations and smoking history). Phase II of the study (1998-2003) updated information on occupational exposures, diet, work practices and medical history by means of a computer assisted telephone interview. We also collected buccal cells on sample of 34,000 study participants to assess the effect of inheritable polymorphisms and the interaction of environment and genomic predisposition.

The stimulus for this prospective investigation comes from the growing evidence that, despite a low mortality overall, farmers experience an excess of several cancers. These excesses have been observed in retrospective epidemiological studies among agricultural workers in several countries. Excess cancers are observed for the lymphatic and hematopoietic system, connective tissue, skin, brain, prostate, stomach and lips. Several of these tumors (brain, NHL, multiple myeloma, and prostate) are also increasing in the general population in many of these countries. This suggests a common set of exposures may explain the high rates in farmers and rising rates in the general population.

Farmers, their families, and other pest control workers may have contact with a variety of potentially hazardous substances including pesticides, solvents, fuels and oils, engine exhaust, dust and zoonotic viruses and other microbes. Our cohort study includes all registered pesticide applicators in Iowa and North Carolina and the spouse of applicators who are farmers. The health effects of pesticide use are the primary focus of the study. The influence of other farm exposures are also being evaluated.

The focus of the phase II follow-up period (2004-2008) is to update exposure information and health histories by means of a computer assisted interview and also following the cohort to determine disease incidence and mortality. The cohort is being followed through the cancer registries within Iowa and North Carolina, the Social Security Administration database, state vital statistics offices, National Death Index, and various in-state databases, such as the listing of registered pesticide applicators. Individuals who enrolled into the study but who are no longer at the address given during enrollment (based on subsequent attempts at follow up) have been submitted and will continue to be submitted (through NIOSH) in the standard format to the IRS under their Project 057 Taxpayer Address Request Program. Identifying data provided to the IRS include only SSN and the first four letters of last name of cohort member. IRS provides in return the most current address in IRS records if a match (SSN + all four letter of last name) is found. The purpose of this effort is to identify members of the cohort who have moved out of state, to enable adjustment of person-years for incidence and mortality calculations. Persons who have moved out of state can be followed for vital status and cause of death, but not for cancer incidence.

Continuation of the protocol will provide a valuable epidemiologic resource to help prevent cancers in the future by identifying risk factors in the rural/agricultural environment. Because more cases of important cancer outcomes occur in this cohort every year, potential cancer causes can be evaluated with increased statistical power. Larger number of cases also allows for statistical control of confounding factors, making more meaningful conclusions about cancer risk, and, for some relatively infrequent cancers, such as the lyphomas and leukemias, greater follow-up time is necessary to make any meaningful observations.

Condition or disease
Prostate Cancer Pesticide Exposure Lymphoma Multiple Myeloma

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Study Design

Study Type : Observational
Estimated Enrollment : 90500 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: The Main Agricultural Health Study - A Prospective Study of Cancer and Other Diseases Among Men and Women in Agriculture
Study Start Date : April 30, 1993

Groups and Cohorts

Outcome Measures

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 89 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

All registered pesticide applicators in Iowa and North Carolina and the spouse and children of applicators who are farmers.

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): NCT00352924

United States, Iowa
University of Iowa
Iowa City, Iowa, United States, 52242
United States, North Carolina
Research Triangle Institute
Research Triangle Park, North Carolina, United States, 27709
Sponsors and Collaborators
National Cancer Institute (NCI)
Environmental Protection Agency (EPA)
Principal Investigator: Laura Beane-Freeman National Cancer Institute (NCI)
More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: National Cancer Institute (NCI)
ClinicalTrials.gov Identifier: NCT00352924     History of Changes
Other Study ID Numbers: 999993013
First Posted: July 17, 2006    Key Record Dates
Last Update Posted: January 10, 2018
Last Verified: December 29, 2017

Keywords provided by National Institutes of Health Clinical Center (CC) ( National Cancer Institute (NCI) ):

Additional relevant MeSH terms:
Multiple Myeloma
Neoplasms, Plasma Cell
Neoplasms by Histologic Type
Hemostatic Disorders
Vascular Diseases
Cardiovascular Diseases
Blood Protein Disorders
Hematologic Diseases
Hemorrhagic Disorders
Lymphoproliferative Disorders
Immunoproliferative Disorders
Immune System Diseases