Rate of severe and fatal infections in a cohort of patients with interstitial lung disease associated with rheumatoid arthritis: a multicenter prospective study.

Objective: To describe severe infection, foci of infection, microorganisms, associated factors, and impact on mortality in patients with rheumatoid arthritis-associated interstitial lung disease (RA-ILD). Patients and methods: The study was based on a multicenter prospective cohort of patients with RA-ILD followed up from 2015 to 2023. The main outcome measures were incident severe infection and fatal infection. We evaluated infectious foci, etiologic agents, vaccination status, variables associated with lung function, and clinical-therapeutic variables in RA. The incidence rate (IR) for infection and mortality was calculated per 100 person-years, and 3 multivariate models were constructed to explore factors associated with infection. Results: We followed up 148 patients with RA-ILD for a median 56.7 months (699.3 person-years). During this period, 142 patients (96%) had at least 1 infection. A total of 368 infectious episodes were recorded, with an IR of 52.6 per 100 person-years. Of the 48 patients who died, 65% did so from infection. Respiratory infections were the most common first infection (74%), infection overall (74%), and fatal infection (80%) and were caused mostly by SARS CoV-2, Streptococcus pneumoniae, Pseudomonas aeruginosa, and influenza A virus. The factors associated with an increased risk of infection and death in patients with RA-ILD were age, inflammatory activity, and therapy with corticosteroids and immunosuppressants. Conclusion: Patients with RA-ILD have a high risk of serious infection, especially respiratory infection. Infection develops early, is recurrent, and is frequently fatal. The presence of associated factors such as advanced age, joint inflammation, and treatment highlight the importance of integrated and preventive medical care.

Safety and Effectiveness of Abatacept in a Prospective Cohort of Patients with Rheumatoid Arthritis-Associated Interstitial Lung Disease.

OBJECTIVE: To prospectively evaluate the safety and efficacy profile of abatacept in patients with rheumatoid arthritis-associated interstitial lung disease (RA-ILD). METHODS: We performed a prospective observational multicenter study of a cohort of patients with RA-ILD treated with abatacept between 2015 and 2021. Patients were evaluated using high-resolution computed tomography and pulmonary function tests at initiation, 12 months, and the end of follow-up. The effectiveness of abatacept was evaluated based on whether ILD improved, stabilized, progressed, or was fatal. We also evaluated factors such as infection, hospitalization, and inflammatory activity using the 28-joint Disease Activity Score with the erythrocyte sedimentation rate (DAS28-ESR). Cox regression analysis was performed to identify factors associated with progression of lung disease. RESULTS: The study population comprised 57 patients with RA-ILD treated with abatacept for a median (IQR) of 27.3 (12.2-42.8) months. Lung disease had progressed before starting abatacept in 45.6% of patients. At the end of follow-up, lung disease had improved or stabilized in 41 patients (71.9%) and worsened in 13 (22.8%); 3 patients (5.3%) died. No significant decreases were observed in forced vital capacity (FVC) or in the diffusing capacity of the lung for carbon monoxide (DLCO).The factors associated with progression of RA-ILD were baseline DAS28-ESR (OR [95% CI], 2.52 [1.03-3.12]; p = 0.041), FVC (OR [95% CI], 0.82 [0.70-0.96]; p = 0.019), and DLCO (OR [95% CI], 0.83 [0.72-0.96]; p = 0.018). Only 10.5% of patients experienced severe adverse effects. CONCLUSION: Pulmonary function and joint inflammation stabilized in 71% of patients with RA-ILD treated with abatacept. Abatacept had a favorable safety profile.