RHEUMATOID arthritis associated interstitial lung disease (RA-ILD) is increasingly recognized as a major factor influencing long-term outcomes in affected patients, with new data showing that disease progression and specific lung patterns significantly impact mortality.
A comprehensive retrospective study of adults with RA-ILD followed at Ajou University Hospital between 1999 and 2022 examined clinical features, progression rates, and risk factors linked to survival. Participants had a mean age of 64.3 years, and nearly half were male. More than one-third were current or former smokers. The average duration of rheumatoid arthritis was over 11 years, while ILD had persisted for more than 7 years at the time of evaluation.
Pulmonary function testing revealed an average forced vital capacity of 81.9 L and a mean diffusing capacity for carbon monoxide (DLco) of 58.7 mL/min/mm, suggesting reduced gas exchange capacity in many patients. Imaging findings were particularly notable, with 60.3% of participants demonstrating the usual interstitial pneumonia (UIP) pattern, which has been historically linked to poor outcomes.
During a mean follow-up period of 4 years, ILD progression was observed in 58.3% of patients, and the overall mortality rate reached 21.2%. Both ILD progression and the presence of a UIP pattern were independently associated with higher mortality, underscoring the need for early identification and vigilant monitoring of high-risk subgroups. Interestingly, methotrexate therapy did not influence disease progression or survival in this cohort, an observation that may challenge longstanding concerns regarding its pulmonary toxicity.
The findings highlight the heterogeneity of RA-ILD and reinforce the importance of individualized management strategies. Close follow-up with pulmonary function testing and imaging, combined with a nuanced approach to therapy, will be key to improving outcomes in this complex patient population.
Reference:
Kim J-W et al. Comprehensive analysis of patients with rheumatoid arthritis associated interstitial lung disease. Korean J Intern Med. 2025. doi: 10.3904/kjim.2024.377
