Impact of Rheumatoid Arthritis and Seropositivity on the Risk of Non-Cystic Fibrosis Bronchiectasis.

BACKGROUND: Despite the coexistence of bronchiectasis and rheumatoid arthritis (RA) and the poor prognosis associated with the combination of conditions, no longitudinal studies that comprehensively evaluated whether patients with RA have a higher risk of bronchiectasis compared with those without bronchiectasis have been published. Whether seropositivity is associated with an increased risk of bronchiectasis in RA is the subject of ongoing controversy.

RESEARCH QUESTION: Does RA influence the development of bronchiectasis? Is seropositivity associated with an increased risk of bronchiectasis in RA?

STUDY DESIGN AND METHODS: The incidence of bronchiectasis was compared between individuals with RA (n=50,651; 35,879 seropositive RA [SPRA] and 14,772 seronegative RA [SNRA]) and 1:5 age- and sex-matched controls (n=253,255) enrolled between 2010 and 2017 in the Korean National Health Insurance Service database. The participants were followed from 1 year after RA diagnosis or the corresponding index date to the date of bronchiectasis incidence, censored date, or December 2019.

RESULTS: The cumulative incidence of bronchiectasis at 9 years of follow-up was approximately 7% in participants with RA. During a median follow-up of 4.3 years (interquartile range, 2.6-6.3 years), participants with RA showed a 2.12-fold higher risk of developing bronchiectasis compared with matched controls even after adjusting for potential confounders related to bronchiectasis development (95% confidence interval [CI], 2.00-2.25), In an analysis of RA serologic status using a fully adjusted model, participants with SPRA and those with SNRA showed 2.34-fold (95% CI, 2.20-2.49) and 1.56-fold (95% CI, 1.40-1.73) increased risks, respectively, compared with matched controls.

INTERPRETATION: Individuals with RA had approximately twice the risk of developing bronchiectasis than matched controls even after adjusting for potential confounders. The increased risk was more evident in individuals with SPRA than in those with SNRA, implying that rheumatic inflammation plays a major role in the development of RA-bronchiectasis.