Rheumatoid arthritis-associated interstitial lung disease in countries across the world.

Area of Science:

• Rheumatology
• Pulmonology
• Epidemiology

Background:

• Rheumatoid Arthritis (RA) is a chronic autoimmune disease that can affect multiple organs, including the lungs.
• Rheumatoid Arthritis-Interstitial Lung Disease (RA-ILD) is a serious complication of RA, impacting patient morbidity and mortality.
• Understanding the global incidence and risk factors for RA-ILD is crucial for patient management.

Purpose of the Study:

• To determine the global incidence of RA-ILD across five countries.
• To investigate the association between RA disease activity and the development of RA-ILD.

Main Methods:

• Data from 16,663 RA patients were analyzed from two observational databases (METEOR, EAC) across five countries.
• RA-ILD diagnosis was based on clinical assessment, including chest X-ray or CT scans.
• Statistical analyses explored the relationship between disease activity scores (DAS28) over time and RA-ILD incidence.

Main Results:

• The prevalence of RA-ILD varied by country, ranging from 0.09% in The Netherlands to 1.42% in Mexico.
• Incidence rates per 1000 patient-years were reported for The Netherlands (3.8), India (1.6), and South Africa (6.6).
• Higher disease activity post-diagnosis was observed in RA-ILD patients compared to controls (β=0.56), with no significant difference in DMARD use.

Conclusions:

• RA-ILD incidence in routine RA care is generally low across diverse global populations.
• Patients diagnosed with RA-ILD exhibit increased disease activity and are more frequently positive for ACPA or have a history of smoking.
• These findings underscore the importance of monitoring lung health in RA patients, particularly those with higher disease activity.