Acute exacerbation of rheumatoid arthritis–associated interstitial lung disease: clinical features and prognosis

• Published in: Rheumatology (Oxford, England) Vol. 60; no. 5; pp. 2348 - 2354
• Main Authors: Izuka, Shinji, Yamashita, Hiroyuki, Iba, Arisa, Takahashi, Yuko, Kaneko, Hiroshi
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 14.05.2021
• Subjects: MTX; acute exacerbation; usual interstitial pneumonia; interstitial lung disease; RA
• ISSN: 1462-0324; 1462-0332; 1462-0332
• DOI: 10.1093/rheumatology/keaa608

Abstract Objectives RA-associated interstitial lung disease (RA-ILD) is commonly associated with acute exacerbations (ILD-AE). This study examined the clinical characteristics and risk factors of ILD-AE and mortality of RA-ILD. Methods We retrospectively collected data on 165 RA-ILD patients who visited or were admitted to our hospital between January 2007 and December 2019. We compared the clinical characteristics of patients who did and did not develop ILD-AE and identified variables significantly associated with ILD-AE. We also compared the admission characteristics of those who survived and those who died after admission for ILD-AE. ILD-AE was defined using previously proposed criteria, modified slightly for application to RA-ILD. Results The mean patient age was 73.6 years (s.d. 9.7) and 97 (71.9%) patients were female. Thirty (22.2%) patients developed ILD-AE, 13 (43.3%) of whom died. In univariate analyses, neither the usual interstitial pneumonia (UIP) pattern nor MTX was associated with ILD-AE. In multivariate analyses, the UIP pattern was significantly associated with ILD-AE [odds ratio (OR) 2.55 (95% CI 1.05, 6.20), P = 0.038]. In the Cox proportional hazards model, the UIP pattern [hazard ratio (HR) 4.67 (95% CI 1.02, 21.45), P = 0.048] was significantly associated with death, while MTX use [HR 0.16 (95% CI 0.04, 0.72), P = 0.016] was significantly associated with survival. Conclusion Our data suggest that the UIP pattern is related to ILD-AE. Furthermore, both the UIP pattern and non-use of MTX might be related to death from ILD-AE in RA-ILD.