Comprehensive analysis of patients with rheumatoid arthritis associated interstitial lung disease

To investigate the demographics, disease characteristics, and treatment modalities of patients with rheumatoid arthritis (RA) associated interstitial lung disease (ILD), focusing on ILD exacerbation and mortality.

This retrospective study included individuals aged ≥ 18 years diagnosed with RA-ILD at Ajou University Hospital from January 1999 to March 2022. Diagnosis was based on chest computed tomography (CT) scans; progression was monitored based on available follow-up pulmonary function tests (PFTs) and chest CTs. Logistic regression analysis identified factors associated with ILD progression and mortality.

The study included participants with a mean age of 64.3 years, 48.3% of whom were male. Smoking status: 13.2% ex-smokers, 25.2% current smokers, 61.6% non-smokers. Mean RA and ILD duration were 134.0 and 87.5 months, respectively. Mean Disease Activity Score in 28 joints was 4.9. The usual interstitial pneumonia (UIP) pattern was seen in 60.3%. Baseline PFT showed a mean FVC of 81.9 L, diffusing capacity for carbon monoxide (DLco) of 58.7 mL/min/mm, and DLco corrected for alveolar volume of 83.4 mL/min. With a mean follow-up of 4 years, ILD progressed in 58.3% of patients, with a mortality rate of 21.2%. ILD progression and UIP pattern significantly influenced mortality. Methotrexate use did not impact progression or mortality.

RA-ILD patients showed diverse clinical profiles, with ILD duration and UIP pattern significantly affecting prognosis. Personalized management and vigilant monitoring are essential to improve outcomes for RA-ILD patients.