Therapeutic strategies for interstitial lung diseases in rheumatoid arthritis

Abstract

Pulmonary involvement is common in rheumatoid arthritis (RA) and affects all components of the lung. Interstitial lung disease (ILD) is the most predominant pulmonary manifestation and has been identified as the main cause of morbidity and mortality in RA. There are distinct histological and/or radiological subtypes in RA-associated ILD (RA-ILD) with different clinical phenotypes and natural courses. An optimal treatment for RA-ILD has not yet been established, because there have been no randomized controlled trials on RA-ILD. Current therapeutic regimens typically include corticosteroids with or without immunosuppressive drugs; however, supporting evidence is limited by the small numbers of patients and uncontrolled study designs. Several novel agents, such as rituximab, pirfenidone, and nintedanib, are currently under investigation. Furthermore, optimal treatments may differ depending on the histological and/or radiological subtypes of RA-ILD. In order to address these issues, prospective controlled studies with a large number of RA-ILD patients are urgently needed. In this chapter, the treatment of RA-ILD will be described by overviewing recent studies in this field, and the best available evidence to inform a treatment rationale will be provided.