Screening for Rheumatoid Arthritis–Associated Interstitial Lung Disease: Current Evidence and Next Steps Needed for Routine Clinical Use

Abstract

Interstitial lung disease (ILD), characterized by pulmonary fibrosis and/or inflammation, is a common and severe extraarticular manifestation of rheumatoid arthritis (RA). RA-ILD is associated with reduced quality of life and increased mortality. Among people with RA, up to 15% develop clinically significant ILD, and even more have subclinical disease (radiologic abnormalities without symptoms). The most common RA-ILD patterns on chest high-resolution computed tomography (CT) imaging are usual interstitial pneumonia (UIP; the prototypic fibrotic subtype) and nonspecific interstitial pneumonia (the subtype characterized by inflammation). In this narrative review, we detail the current state of evidence for RA-ILD screening and the next steps needed to justify screening in some subgroups. Some current or former smokers with RA may currently qualify for lung cancer screening with low-dose CT imaging, which may also detect ILD. The 2023 American College of Rheumatology (ACR)/American College of Chest Physicians (CHEST) guideline for screening and monitoring of ILD conditionally recommended screening people with RA with an ILD risk factor (ie, male sex, older age, smoking, RA-related autoantibody elevation, obesity, and high RA disease activity). Several genetic and blood biomarkers are associated with RA-ILD. The MUC5B promoter variant is the strongest genetic risk factor for RA-ILD, specifically the UIP subtype. Proposed screening strategies show promise for accurately detecting RA-ILD; however, there has been less research on other consequences of screening for RA-ILD, including cost, anxiety, radiation exposure, incidental findings, and downstream clinical follow-up. Clinical trials are needed to identify an intervention that alters the natural history for those found to have subclinical RA-ILD on screening.