Ultrasound-detected activity in rheumatoid arthritis on methotrexate therapy: Which joints and tendons should be assessed to predict unstable remission?

The aim of the study was to investigate the predictive value of different reduced joint ultrasound (US) assessments of synovitis and tenosynovitis in relation to unstable remission in a cohort of rheumatoid arthritis (RA) patients on methotrexate therapy. Forty-seven RA patients (38 women, 9 men), being treated with methotrexate (MTX), in clinical remission as judged by their consultant rheumatologist were evaluated for disease activity according to the Disease Activity Score (DAS) 28 at baseline and 6 months. Sustained remission and unstable remission were defined according to the baseline and 6-month DAS28 and changes in RA therapy during the follow-up. Each patient underwent at baseline a B-mode and power Doppler (PD) assessment of 44 joints and 20 tendons/tendon compartments by a rheumatologist blinded to the clinical and laboratory data. B-mode synovial hypertrophy (SH), synovial PD signal, B-mode tenosynovitis, and Doppler tenosynovitis were scored 0-3. The presence and index of synovial PD signal in 44 joints [odds ratio (OR) 8.21 (p=0.016) and OR 2.20 (p=0.049), respectively] and in 12 joints [OR 5.82 (p=0.041) and OR 4.19 (p=0.020), respectively], the presence of SH in wrist and MCP joints [OR 4.79 (p=0.045)], and the presence of synovial PD signal in wrist-MCP-ankle-MTP joints [OR 4.62 (p=0.046)] were predictors of unstable remission. The 12-joint or wrist-hand-ankle-MTP US assessments can predict unstable remission in RA patients in apparent clinical remission being treated with MTX.