Correlation of radiographic progression with the cumulative activity of synovitis estimated by power Doppler ultrasound in rheumatoid arthritis: difference between patients treated with methotrexate and those treated with biological agents.

OBJECTIVE: Our prospective study aimed to demonstrate that the cumulative synovial power Doppler (PD) ultrasound scores correlate with radiographic progression better than conventional measures in patients with rheumatoid arthritis (RA). We also investigated the difference between antirheumatic agents.

METHODS: Sixty-nine patients with RA who had recently received either methotrexate (MTX; n = 23), tumor necrosis factor (TNF) antagonists (n = 28), or tocilizumab (TCZ; n = 18) were enrolled. Patients underwent clinical, laboratory, and ultrasonographic assessment at baseline, 12 weeks, and 24 weeks. Radiographic damage was evaluated using van der Heijde modified total Sharp score (TSS) at baseline and 24 weeks.

RESULTS: Fifty-seven patients continued the same treatment regimen for 24 weeks and completed the study, and 21 patients (36.8%) showed radiographic progression during the study period. In all patients, ΔTSS significantly correlated both with cumulative 28-joint Disease Activity Score-C-reactive protein (DAS28-CRP; ρ = 0.342, p = 0.009) and cumulative total PD scores (ρ = 0.357, p = 0.006). In MTX-treated patients, cumulative total PD scores significantly correlated with ΔTSS (ρ = 0.679, p = 0.004), whereas cumulative DAS28-CRP did not (ρ = 0.487, p = 0.056). However, cumulative total PD scores did not correlate with ΔTSS in TNF antagonist-treated or TCZ-treated patients.

CONCLUSION: Our data confirm the evidence that synovial PD activity more accurately reflects active synovial inflammation (which actually causes joint destruction) than do conventional measures in patients treated with MTX. Our data also indicate that TNF antagonists can inhibit short-term radiographic progression in the presence of active synovitis.