Fine particle pollution raises rheumatoid arthritis flare risk and disease activity

Higher ambient PM2.5 exposure was associated with increased rheumatoid arthritis disease activity and a greater likelihood of flares in a four-year South Korean cohort of 1,070 patients. The association appeared stronger with sustained exposure over approximately two weeks or longer, while women and nonsmokers showed more pronounced links between PM2.5 and DAS28-CRP.