Objectives: Although "clinical remission" has been a realistic goal of treatment in rheumatoid arthritis (RA), there is evidence that subclinical synovitis is associated with ongoing structural damage even after clinical remission is achieved. In the study reported here, we assessed whether ultrasonography (US) can predict progressive joint destruction during clinical remission of RA.
Methods: Thirty-one patients with RA in clinical remission based on the disease activity score in 28 joints were recruited for this study. Bilateral wrists and all of the metacarpophalangeal and proximal interphalangeal (PIP) joints were examined by power Doppler (PD) ultrasonography (US), and the PD signals were scored semiquantitatively in each joint. The total PD score was calculated as the sum of individual scores for each joint.
Results: Among 22 RA patients who maintained clinical remission during the 2-year follow-up period, seven showed radiographic progression. Radiographic progression was strongly associated with total PD score at entry, with all patients showing radiographic progression having a total PD score of ≥ 2 at entry and none of the patients with a total PD score of ≤ 1 showing any radiographic progression. There was no significant association of therapeutic agents with progressing or non-progressing cases.
Conclusions: PD-US detects synovitis causing joint destruction even when the patient is in clinical remission. Thus, remission visible on US is essential to reach "true remission" of RA.