Objective: The objective of this study is to examine the clinical, genetic, and environmental factors associated with interstitial lung disease (ILD) in rheumatoid arthritis (RA).
Method: We recruited patients with RA from rheumatology practices at the time of a scheduled visit. Each patient participated in a comprehensive assessment that included ascertainment of age, sex, joint tenderness and swelling, subcutaneous nodules, disease severity, use of methotrexate and prednisone, smoking status, rheumatoid factor (RF), antibodies against cyclic citrullinated peptide (anti-CCP),erythrocyte sedimentation rate (ESR), the 28-joint Disease Activity Score (DAS28), and the presence of the HLA-DRB1 shared epitope (SE).