Older age, lower BMI, seropositivity tied to RA-related bronchiectasis

Isolated bronchiectasis (BR) in rheumatoid arthritis (RA) that is not caused by interstitial lung disease (ILD) is associated with seropositivity, older age at RA diagnosis, and lower body mass index (BMI) at RA onset, a recent study has found.

A case-control study was conducted on RA patients from the Mass General Brigham Biobank. The investigators reviewed the records of all patients meeting the 2010 American College of Rheumatology/European Alliance of Associations for Rheumatology criteria with computed tomography (CT) chest imaging to identify RA-BR cases and controls with RA and RA-related lung disease.

Two radiologists reviewed the CT chest imaging for the presence of RA-related lung diseases. Cases had clinical and radiologic evidence of RA-BR without interstitial lung abnormalities on imaging, while controls had RA and no evidence of BR or ILD. Finally, multivariable logistic regression was used to examine the associations of demographic, lifestyle, and serologic factors with RA-BR.

A total of 57 cases of isolated RA-BR and 360 RA controls without RA-related lung disease were included in the analysis.

Multivariate analysis revealed the association of RA-BR with older age at RA onset (odds ratio [OR], 1.37 per 10 years, 95 percent confidence interval [CI], 1.02‒1.82), lower BMI at RA diagnosis (OR, 0.94 per kg/m², 95 percent CI, 0.89‒0.99), seropositive RA (OR, 3.96, 95 percent CI, 1.84‒8.53), positive rheumatoid factor (OR, 4.40, 95 percent CI< 2.14‒9.07), and positive anticyclic citrullinated peptide (OR, 3.47, 95 percent CI, 1.65‒7.31).

Furthermore, higher titres of RA-related autoantibodies correlated with a greater likelihood of RA-BR.

“These findings expand the list of potential risk factors for RA-BR and suggest a pathogenic link between airway inflammation and RA-related autoantibodies,” the investigators said.