Background/Purpose: Remission in rheumatoid arthritis (RA) is often assessed using the following indices: disease activity scores (DAS-28), clinical disease activity index (CDAI), Simplified Disease Activity Index (SDAI) and Routine Assessment of Patient Index Data (RAPID-3). There is increasing literature supporting the benefits of using imaging modalities to better define remission in RA. Musculoskeletal ultrasound (MUS) allows for direct visualization of diverse pathologic features such as cortical bone erosions, synovial thickening, and synovial vascularity in the joints affected by RA with high sensitivity, specificity, and accuracy. The purpose of this study was to investigate the association between clinical outcome measures and ultrasound score of the dominant hand in RA patients.

Methods: This was a single center study of patients from the RA clinic at the University of Rochester seen between July 2015 and April 2017. The DAS-28, CDAI, SDAI are collected as standard of care in the RA clinic. Patients are also offered the option of doing the RAPID-3 and getting MUS evaluations as part of their assessment. All clinical measures were collected by AA and AC. MUS exams were done by RT, who was blinded to the clinical scores, using a GE Logiq E9 (2014 model). MSK evaluations were done, using frequencies of 15-18 MHz for gray scale (GS). The following joints were assessed: dorsal wrist, 2nd, 3rd, 4th and 5th MCPs and the 2nd, 3rd, 4th and 5th PIP. MCP joints 2-5 were scanned from a dorsal aspect, and PIP joints 2-5 were scanned from a volar aspect. The scans were retrospectively scored for presence of synovitis on GS and Power Doppler (PD) (0=none; 1=mild; 2=moderate and 3=severe) for each joint. A total score was calculated by adding GS and PD scores and compared to clinical measures.

Results: A total of 113 patients volunteered for MUS but complete data were available in only 67. The median age of the group was 61 years and comprised 41 females and 26 males, with 62 being sero-positive and 38 with erosive disease. A total of 26 patients were in remission by DAS-28(CRP), 12 by CDAI, 14 by SDAI and 9 by RAPID-3, criteria. Low disease activity was seen in 11 by DAS-28, 17 by CDAI, 22 by SDAI and 9 by RAPID-3 criteria while 25, 24, 19 and 18 patients were with moderate disease activity and 5, 14, 12 and 31 had high disease activity, respectively. The median scores on MUS GS and PD for each category of disease activity are shown in Table 1. Interestingly, the median score on PD was 0 for remission by all outcome measures. MUS scores were associated with disease activity scores and a positive correlation was detected between MUS (GS and PD) scores and DAS-28 scores.

Conclusion: Most patients in clinical remission as assessed by DAS-28, CDAI, SDAI and RAPID-3 had no activity on PD and low scores on GS MUS evaluations. MUS of the dominant hand, using a simple scoring system, can be as effective in defining remission.

Table 1: Ultrasound scores (GS and PD) for each category of clinical disease activity

ACR Meeting Abstracts - https://acrabstracts.org/abstract/majority-of-rheumatoid-arthritis-patients-in-clinical-remission-as-defined-by-das-28-cdai-sdai-and-rapid-3-have-no-signal-on-ultrasound-power-doppler/