Primary objective
: Comparison of prognosis between RA-ILD and RA-non ILD patients
Secondary objectives
1. Identification of the prognostic factors or aggravation factors of ILD in RA-ILD patients
2. Identification of the association between ILD and autoantibody profiles in RA-ILD patients
3. Comparison of RA disease activity control between RA-ILD and RA-non ILD patients using disease activity score (DAS)28-erythrocyte sedimentation ratio (ESR), DAS28 C-reactive protein (CRP), simple disease activity index (SDAI) and clinical disease activity index (CDAI)
4. Comparison of biologic and non-biologic DMARD treatment response in RA-ILD patients using disease activity parameters
The study population will be adult RA patients who have checked a chest computed tomography (CT) scan within 2 years of enrollment. No additional visits or laboratory tests will be done outside the routine clinical practice for RA-non ILD patients. For RA-ILD patients, high resolution computed tomography (HRCT), pulmonary function test (PFT) and 6-min walk test will be examined annually to identify the progression of ILD. Selection of medication including conventional DMARDs, biologic DMARDs, glucocorticoid, and inhaler, dosing and treatment duration are at the discretion of the investigator.
