Synovitis and Tenosynovitis on Ultrasound as Predictors of DMARD Tapering Failure in Patients with Long-Standing Rheumatoid Arthritis in Clinical Remission or Low Disease Activity

Objectives This study aimed to investigate the predictive value of synovitis and tenosynovitis detected by grayscale (GS) and by power Doppler (PD) ultrasound (US) in relation to failure of tapering disease-modifying antirheumatic drugs (DMARD) in rheumatoid arthritis (RA) patients. Methods Long-standing RA patients who de-escalated treatment were included in this prospective cohort study. All patients underwent 3 ultrasonographic and clinical assessments, at baseline and every 3 or 4 months, over a period of 6-8 months. US investigation of 32 joints was performed. Synovitis was assessed by GS and PD semiquantitative scoring (0-3) and a global score was calculated for each individual by summing single joint scores. The presence of tenosynovitis was recorded whenever detected during ultrasound assessment. Results Thirty-three patients completed the follow-up period (29 women; 4 men). Eight patients (25%) relapsed. Using the optimal cutoff values determined by receiver operating characteristic curve, patients with a PD synovitis >= 1 at baseline had significantly greater chances to relapse than those without PD activity. During follow-up, GS tenosynovitis was detected in 6 patients (5 with PD) who failed and in 3 patients (1 with PD) who succeeded in tapering therapy. Having at least 1 joint with PD synovitis resulted in a relative risk of 3.14 and having GS tenosynovitis resulted in a relative risk of 11.4 (95% CI: 1.03-9.60 and 2.82-45.9, respectively) for relapse in the multivariate Poisson model. Conclusions PD synovitis and GS tenosynovitis may be useful to identify RA patients in risk of relapse after DMARD tapering.