Grade and location of power Doppler are predictive of damage progression in rheumatoid arthritis patients in clinical remission by anti-tumour necrosis factor α.

Abstract

To investigate power Doppler (PD) signal, grade and location and their association with radiographic progression in RA patients in remission. A prospective observational study was conducted in 125 consecutive RA patients in stable 28-joint DAS (DAS28) remission (⩾6 months) achieved on anti-TNF-α. At baseline, patients in stable remission underwent radiographic and US examination of the wrists and MCP, PIP and MTP joints. Semi-quantitative PD scoring (0-3) was recorded. We scored PD according to two locations: capsular or within synovial tissue without bone contact (location 1) and with bone contact or penetrating bone cortex (location 2). Radiographic progression was evaluated at the 1 year follow-up and defined as a change in van der Heijde-modified total Sharp score >0. Risk ratios (RRs) of radiographic progression according to presence, grade and location of PD were calculated. Four patients were excluded because of missing data. At baseline, 59/121 (48.7%) patients had a PD signal in one or more joints. PD location 2 was found in 74.6% patients (44/59). At the 1 year follow-up, 17/121 patients experienced radiographic progression: all had PD signal in one or more joints at baseline (RR 2.47, P < 0.0001). Radiographic progression was associated with the following baseline US features: PD grade 2 (RR 4.58, P < 0.01), PD grade 3 (RR 3.49, P < 0.05), total PD score ⩾2 (sum of all PD scores) (RR 3.19, P < 0.0001) and PD location 2 (RR 3.49, P < 0.0001). Higher PD grades and PD in contact with/or penetrating bone are associated with radiographic progression in patients in DAS28 remission.