EFFECTS OF EARLY DIAGNOSIS ON DISEASE ACTIVITY AND FUNCTIONAL DISABILITY IN RHEUMATOID ARTHRITIS

Abstract

Background Early and aggressive treatment offers better outcomes in early rheumatoid arthritis (RA). The long-term effect of early treatment and effect of early treatment on functional disability have not been studied.Objectives To determine whether early diagnosis and treatment have long-term benefits for disease activity and functional disability in patients with RA enrolled in the KORean Observational study Network for Arthritis (KORONA).Methods A total of 4540 rheumatoid arthritis patients completed questionnaires to establish their demographic profile, medical history, disease-specific outcomes, and RA-related information. We defined early and delayed RA diagnoses as lag-times of shorter than and at least 1 year. Disease activity was measured with the DAS28?ESR, and it was dichotomized using a score of 2.6. Functional disability was measured with the Korean HAQ-DI, and was dichotomized using a score of 1. We used the chi-square test and t-test to identify differences between male and female patients, and crude and multiadjusted models to identify the impacts of early diagnosis on disease activity and functional disability.Results In crude and multiadjusted models, early diagnosis was not associated with a higher remission rate (OR 1.10, CI 0.94-1.28 in crude model, OR 1.05, CI 0.83-1.32 in multiadjusted model). We performed subgroup analysis according to disease duration; there was no association between early diagnosis and remission rate. Early diagnosis was associated with functional disability in crude model (OR 0.79, CI 0.68-0.91) but not in multiadjusted model (OR 0.85, CI 0.72-1.002). In subgroup analysis according to disease duration and disease activity, early diagnosis was independently associated with functional disability for a shorter disease duration (OR 0.78, CI 0.63-0.96 in disease duration <10 years) and the presence of moderate-to-severe disease activity (OR 0.83, CI 0.69-0.99 in DAS28-ESR ≥3.2).