Dirty air is bad for everyone, but it affects people with rheumatoid arthritis (RA) more than others, according to a new study.

The All India Institute of Medical Sciences (AIIMS) recently surveyed 500 RA patients in New Delhi, India, over 10 years.

RA Pollution

The results showed higher instances of RA symptoms when pollution was bad. The correlation between bad air and worsening joint pain and swelling was surprisingly strong, researchers said.

Uma Kumar, a department head and professor of rheumatology medicine at AIIMS who also worked on the study, said, “We collected data on air quality from the Indian Meteorological Department in New Delhi for the past few years and then tracked patients undergoing treatment for rheumatoid arthritis here at AIIMS. Patients showed worsening of symptoms like joint pain and swelling when the air pollutants increased.”

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Effects in the United States

More than 1.5 million adults live with RA in the United States. Cities like Los Angeles and Pittsburgh struggle with smog, pollution, and air quality.

Pennsylvania has a higher-than-average national rate of arthritis with 1 in 3 adults living with one or more forms of arthritis, compared to the national average of 1 in 5 adults.

Pittsburgh organizations like GASP (Groups Against Smog and Pollution) don’t directly speak out about RA but constantly comment on the link between pollution and health problems.

Another study, done in 2014 in Britain and published in the Environmental Health Perspectives journal, showed that proximity to traffic may also increase RA symptoms. Studies like these show indirect evidence that RA flares and air pollution could be related.

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Patients Discuss Aches, Pains

Some patients say they have noticed the correlation.

“I always feel better when [I’m] in areas with cleaner air. Maybe also because those are less stressful places to be,” said RA patient Sally Estes.

Estes, who lives in DeKalb, Illinois, added “The minute I breathe the air in Colorado or Montana, I feel better.”

But not all patients are so sure.

Brooke B. said in an online comment, “I don’t [see a correlation]. However, humidity sometimes kills my joints because I live in Hawaii.”

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