The research article published in Arthritis Care & Research point out that patients with certain occupations that involve exposure to potentially noxious airborne agents appear to be at an increased risk of developing rheumatoid arthritis.

Certain environmental factors thought to influence the risk of developing rheumatoid arthritis by activating autoimmune reactions in susceptible individuals.

Anna Ilar, Karolinska Institutet in Sweden, and her team analyzed 3522 cases with rheumatoid arthritis and 5580 controls from the Swedish population-based EIRA (Epidemiological Investigation of Rheumatoid Arthritis) study to investigate the involvement of occupational hazards and exposures.

The researcher team analyzed participants' smoking habits, alcohol use, educational level, and body mass index, all of which are factors associated with rheumatoid arthritis.

Anna Ilar said that those lifestyle-related risk factors were not considered in earlier studies. “Our findings, therefore, indicate that work-related factors, such as airborne harmful exposures, may contribute to disease development,” she added.

The investigators also analyzed the surveys conducted in the time period of 1996 to 2014 and collected information on environmental, genetic, and immunological factors from the blood samples. They found that male employees in the manufacturing segment had a higher risk of developing rheumatoid arthritis than employees within the professional, administrative, and technical segments.

Within the manufacturing segment, male electrical and electronics employees and material handling operators were showed two times elevated risk of rheumatoid arthritis whereas bricklayers and concrete workers showed three times than the reference group.

Among women employees, assistant nurses and attendants had a slightly increased risk of rheumatoid arthritis within the professional, administrative, and technical segments. None of the employees from manufacturing sector had a risk of rheumatoid arthritis; it might be due to the small number of women employees who work in this segment.

Ilar suggested, "It is important that findings on preventable risk factors are spread to employees, employers, and decision-makers in order to prevent disease by reducing or eliminating known risk factors."

In conclusion, more studies are required to identify the exposures that increase the risk of rheumatoid arthritis. Possible exposures include silica, asbestos, organic solvents, and motor exhaust.