Structural deterioration of finger joints with ultrasonographic synovitis in rheumatoid arthritis patients with clinical low disease activity

Objective. In this study we investigated the relationship between synovial vascularity (SV) and structural alteration of finger joints in patients with RA and long-term sustained clinical low disease activity (CLDA). Methods. RA patients with CLDA of >2 years (minimum 1 year of CLDA for study entry plus 1 year of observation) were analysed. Quantitative SV values were sequentially measured in each finger joint using power Doppler ultrasonography (0, 8, 20 and 52 weeks). Radiological progression of local finger joints was evaluated according to the Genant-modified Sharp score (052 weeks). Results. Of the 25 patients enrolled, 15 patients were finally analysed after excluding 10 patients who failed to maintain CLDA during the observational period. Changes in radiological progression of MCP and PIP joints with positive SV were significantly greater than those in joints with negative SV. Joint space narrowing (JSN) was strongly related to structural alteration of finger joints. In joints with positive SV, changes in structural alteration did not relate to total SV values, which reflect total exposure to inflammation in an observational period. Conclusion. Even in patients with a long period of CLDA, finger joints with positive SV showed structural alteration, especially in the progression of JSN. Trial registration: University Hospital Medical Information Network Clinical Trials Registry, http://www. umin.ac.jp/ctr/, UMIN000007305.