Characteristics of patients with rheumatoid arthritis in clinical remission: the many aspects of DAS28 remission

Objective. The aim of this study was to observe the clinical characteristics, including the extent of foot and ankle involvement, of Korean patients with rheumatoid arthritis (RA) in remission, defined as Disease Activity Score in 28 joints (DAS28) <2.6. Methods. Data from a registry of RA patients who visited a rheumatology clinic of a university-affiliated hospital and who were regularly evaluated with DAS28, including the ankle and foot metatarsophalangeal (MTP) joints were enrolled. Patients who were treated with disease-modifying anti-rheumatic drugs for at least three months and who were in DAS28 remission were included in this study. Results. Two hundred and thirteen episodes of DAS28 remission were observed in 147 patients. The mean DAS28 value at the time of remission was 1.84 (range, 0.14-2.59). The mean numbers of swollen joints and tender joints (of the 28 joints examined for DAS28) at the time of remission was 0.4 (range, 0-6) and 1.5 (range, 0-13), respectively. Overall, 11.7% and 38% of the patients in clinical remission had foot MTP/ankle swollen and tender joints, respectively. Additionally, 7% and 8.9%, respectively, of the patients in clinical remission had foot MTP/ankle swollen and tender joints without any involvement of the 28 joints included in the DAS28. Conclusion. Our results show that RA patients in DAS28 remission frequently have residual disease activity in the ankle and foot joints. Given that forefoot disease activity can lead to joint damage and disability with respect to weight-bearing activities, these joints should be included in the clinical examination.