Profile of Patients with Rheumatoid Arthritis-Associated Interstitial Lung Disease: A Single-Center Study

Background: Rheumatoid arthritis-associated interstitial lung disease (RA-ILD) is a well-described complication of rheumatoid arthritis (RA). The authors sought to describe the characteristics, treatment strategies, and outcomes of RA-ILD patients at 6 and 12 months. Methods: Patients treated at the medical center between 2010 and 2019 with ICD9 and ICD10 codes for RA and interstitial lung disease (ILD) meeting American College of Rheumatology 1987 or 2010 ACR/European League Against Rheumatism classification criteria were considered for inclusion. The diagnosis of RA-ILD was based on clinical features, pulmonary function testing (PFT), and high-resolution computed tomography (HRCT) findings. Baseline demographics, body mass index , serologic status, tobacco use, PFT and HRCT findings, and RA-ILD treatments at 0, 6, and 12 months were extracted and analyzed. Results: Forty-seven patients diagnosed with RA-ILD were included in this analysis. The median age at diagnosis was 64.7 years, and the median duration of follow-up was 30 months. Thirty-two patients (68.09%) had follow-up data available at 6 months and 27 (57.45%) had follow-up data at 12 months. Twenty-three (48.9%) patients received treatment for RA-ILD. Forty-three (90.6%) and 42 (88.9%) patients exhibited stability/improvement of RA-ILD at 6 and 12 months of follow-up, respectively. Progression of RA-ILD at 6 months was associated with tobacco use (P=.025); however, no specific variable was associated with RA-ILD progression at 12 months. Conclusions: Patients with RA-ILD receiving treatment tend to show improvement or stability in lung disease at 6 and 12 months, although high attrition rate and short follow-up preclude finding of additional factors associated with ILD. Trial registration: Not applicable.