Study links exposure to workplace fumes and dusts to elevated risk of rheumatoid arthritis

Stockholm — Exposure to dusts and fumes from common workplace agents such as vapors, gases and solvents may increase workers’ risk of developing rheumatoid arthritis, results of a recent study out of Sweden show.

Rheumatoid arthritis, which affects nearly 1% of the world’s population, is a chronic autoimmune joint disease that involves painful – and often disabling – inflammation. The disease is characterized by the presence or absence of anti-citrullinated protein antibodies. Positivity for ACPA is linked to a worse prognosis of RA and higher rates of erosive joint damage.

For their study, researchers examined data from the Swedish Epidemiological Investigation of RA. They looked at more than 4,000 adults diagnosed with the disease between 1996 and 2017, along with a comparison group of almost 6,500 others who didn’t have RA but matched the other participants in age and sex. Participants provided their personal job histories, which were used to estimate individual exposures to 32 different airborne workplace agents.

The researchers found that exposure to any workplace vapor, gas, solvent or other agent was associated with a 25% heightened risk of developing RA. That risk jumped to 40% for men.

More than half of the agents looked at were “strongly associated” with an increased risk of developing ACPA-positive RA. They included quartz, asbestos, carbon monoxide, and diesel and gasoline fumes. The risk of developing RA increased with the exposure to more agents and duration of exposure, the researchers said. The strongest associations to the disease were seen for exposures lasting eight to 15 years.

Exposure to a workplace agent, being a smoker and a high genetic risk score – known as a triple exposure – was associated with an ACPA-positive disease risk ranging from 16% to 68% higher.

The researchers say increased public health efforts are needed.

“First, environmental health initiatives should reduce public exposure to ambient pollutants, including carbon monoxide and gasoline exhaust,” Jeffrey Sparks, a physician who specializes in rheumatology at Brigham and Women’s Hospital in Boston, writes in an editorial on the study. “Second, occupational health initiatives should mitigate occupational hazards, including detergents and asbestos. Third, public health initiatives should continue to reduce cigarette smoking.”

The study was published online in the journal Annals of the Rheumatic Diseases.