Passive smoking can function as an elevated risk factor for RA in women

Passive smoking exposure during childhood and/or adulthood in women increases the risk of rheumatoid arthritis (RA) in the same way as active smoking, as per the recent study findings published in Rheumatic & Musculoskeletal diseases open.

The French prospective study, began in 1990, evaluated passive smoking exposure using self-reported questionnaires in a cohort of healthy women.  RA cases were confirmed by self-reporting and subsequent verification. Among 79806 women, 10,810 (13.5%) women were exposed to passive smoking in childhood, and 42,807 (53.6%) in adulthood. The study identified 698 incident cases of RA.

Assessment of all the models demonstrated significant association between passive smoking in children and adulthood and the risk of RA (HRs 1.24 and 1.19 respectively). Furthermore, the absolute risk of RA noted among never smokers with passive smoking inhalation in childhood and/or adulthood (47.6/100 000 person-years) was similar to that of ever smokers with no passive smoking exposure (47.2/100 000 person-years). While it was highest in ever smokers with passive smoking exposure (53.7/100 000 person-years).

Previous literature evidence has established that smoking enhances citrullination and in genetically predisposed subjects, this may occur years before the onset of symptoms of the disease. The present study findings add to the current understanding of mucosal paradigm of RA pathogenesis. It also highlights the need to restrict such exposure to prevent the disease onset, particularly in people who are at risk of developing RA.

Reference: Nguyen Y, Salliot C, Gelot A, Mariette X, Boutron-Ruault MC, Seror R. Passive smoking in childhood and adulthood and risk of rheumatoid arthritis in women: results from the French E3N cohort study. RMD Open. 2022 Feb;8(1):e001980.