Rheumatoid-arthritis (RA)-related autoimmunity is associated with both quantitative subclinical interstitial lung disease (ILD) phenotypes on computed tomography (CT), particularly among ever tobacco users, a recent study found. Researchers measured serum rheumatoid factor (RF) and anticyclic citrullinated peptide antibody (anti-CCP) and high attenuation areas (HAAs) on cardiac CTs in 6,736 community-dwelling US adults. They measured interstitial lung abnormalities (ILAs) in 2,907 full-lung CTs at a 9.5 year median follow-up. They found:

• In adjusted models, HAA increased by 0.49% per doubling of RF IgM and by 0.95% per RF IgA doubling.

• ILA prevalence increased by 11% per RF IgA doubling.

• Tobacco use modified the links of both RF IgM and anti-CCP with both HAA and ILA.

• Among ever tobacco users, HAA increased by 0.81% and ILA prevalence increased by 14% per RF IgM doubling; and HAA increased by 1.31% and ILA prevalence increased by 13% per anti-CCP doubling.

Citation: Bernstein EJ, Barr RG, Austin JH, et al. Rheumatoid arthritis-associated autoantibodies and subclinical interstitial lung disease: The Multi-Ethnic Study of Atherosclerosis. [Published online ahead of print September 8, 2016]. Thorax. doi:10.1136/thoraxjnl-2016-208932.