Washington, September 30 : Occupational exposures in farming and industry-such as asbestos, solvents, benzene, pesticides and other substances—may increase a person’s likelihood of dying from systemic autoimmune diseases, say researchers.

A team of researcher led by L.S. Gold and A.J. De Roos of the Fred Hutchinson Cancer Research Center in Seattle, Washington, examined death certificate data from 26 states from 1984 to 1998.

Cases that listed a systemic autoimmune disease, such as rheumatoid arthritis, as the cause of death as well as disease types with a suspected systemic autoimmune disease origin like unspecified connective tissue disorder were included in the study. Five control subjects matched by age, sex, race, year of death and geographic region were also selected.

The researchers established each person’s longest-held occupation from the “usual occupation” listed on the death certificate, besides examining specific exposures based on occupation and industry.

It was found that some occupations involving exposure to the public, such as nurses and teachers, were associated with an increased risk of dying from a systemic autoimmune disease, but this was not the case with all jobs involving public exposure, such as food service jobs.

The researchers found that farmers showed increased risk of death from systemic autoimmune disease, particularly for those who worked with crops versus livestock. They also observed an increased risk of death from such diseases among people associated with mining and textile machine operators as well as timber cutting and logging.

Upon further analysis, the researchers discovered that the same occupations and exposures were present in people who were older than the typical retirement age when they died, “implying that the occupational exposures were involved in a chronic pathogenic process leading to either disease incidence or slow progression of existing autoimmunity.”

The researchers believe that higher risk linked with jobs involving public contact might be due to exposure to multiple infectious agents leading to an autoimmune response.

“The size of our study allowed us to estimate associations between specific occupations and death from autoimmune diseases and to generate hypotheses that will be useful as starting points for future studies in this area,” the authors conclude.

In their future studies, the researchers will be focusing on obtaining more detailed occupational histories from the groups found to be at increased risk. (With inputs from ANI)