Radiological extent predicts prognosis and relapse after acute exacerbation of interstitial lung disease in patients with rheumatoid arthritis: KEIO-RA-cohort.

To clarify how the extent of radiological interstitial lung abnormalities impacts the prognosis and risk of relapse in patients with rheumatoid arthritis (RA) following acute exacerbation of interstitial lung disease (AE-ILD). We conducted a retrospective review of all consecutive RA patients from the KEIO-RA cohort who experienced AE-ILD during 2012 to 2024. We investigated the association between the extent of abnormalities on high-resolution computed tomography (HRCT) images, as assessed by Goh's criteria, and outcomes in patients who survived AE-ILD versus those who did not, as well as between patients who survived AE-ILD without relapse and those who experienced relapse. Out of the 34 cases, 10 (29.4%) patients died due to AE-ILD. Of the 26 cases who survived the first AE-ILD event, 8 (30.8%) experienced a relapse, and 2 of them died. Non-survivors had higher Goh's HRCT scores both before and at the time of AE-ILD compared to survivors. Patients who experienced relapse had higher HRCT scores after AE-ILD compared to those who did not relapse. There were no significant differences in treatment regimens for AE-ILD, titers for anti-cyclic citrullinated peptide antibody or rheumatoid factor, or arthritis activity among the groups. Higher HRCT scores both before and at the time of AE-ILD are associated with increased mortality risk, while elevated scores after AE-ILD are linked to a higher likelihood of relapse. These findings highlight the critical role of HRCT assessment in guiding prognosis and post-AE-ILD management in patients with RA.