Background Biologics therapy has been shown to suppress joint destruction regardless of its efficacy for disease activity in rheumatoid arthritis (RA) patients, whereas power Doppler (PD) signal in joint detected by ultrasonography (US) not only illustrates ongoing active synovitis but also predicts subsequent radiologic progression of RA joints.
Objectives To examine whether positive PD signal is associated with radiological joint destruction of RA patients under biologics therapy in daily practice.
Methods RA patients who had been initiated and continued biologics for more than 12 months were included. Clinical, laboratory, and US examinations were conducted sequentially from baseline (1st) to the last observation (last). Bilateral wrists, all MCP and PIP joints were examined by PDUS and the PD signals were graded from 0 to 3 in each joint. The total PD score was defined as the sum of scores of individual joint, and mean score of several assessments during observational period was also calculated. Structural damage of hands at baseline and the last was measured by modified Sharp scoring method for hand X-ray (TSS). Patients having DTSS >0.5 point per year and joints that progressed ≥1 point were defined as showing radiologic progression.
Results Objectives were 102 RA patients (female 86%, age 59.3±13.6 y.o., disease duration 8.4±8.7 years, ACPA positivity 85%, 1st DAS28 4.87±1.38, baseline hand TSS 15.5±16.8). Sixty patients continued the same drug (anti-TNF 30, TCZ 23, ABT 7), whereas 42 switched biologics because of 34 primary or second failure, 10 adverse events, and one complication. During continuing biologics therapy for 33.6±17.6 months, 41% of the patients including 17 who achieved clinical remission experienced radiologic progression. Using linear regression model, PSL dose at baseline, switched agents, 1st and last disease parameters including DAS28, CRP and MMP-3, and last and mean PD score were associated with DTSS on univariate analysis, whereas mean total PD score as well as PSL dose at baseline and last MMP-3 score were independently related to DTSS on multivariate analysis. For joint-based analysis of total 2244 joints, radiologic progression were seen in 121 joints (5.4%), of which wrists were mainly affected joints (30% of all wrists) followed by 2MCP (8.8% of all 2MCPs). Multivariate analysis by generalized linear mixed model revealed that mean PD score in a joint was the most potent risk for subsequent destruction of wrists (OR 3.2, Table). In contrast, none of the factors for destruction was extracted among MCP and PIP joints.
Conclusions This study shows that positive PD signal, especially in wrists, is associated with progressive joint damage of RA patients receiving biologics, suggesting that monitoring of PDUS is helpful for optimizing the treatment along with ‘Treat to Target’ for achieving radiologic remission even under biologics therapy.
Disclosure of Interest None declared