Background The radiographic joint damage in patients with rheumatoid arthritis (RA) is commonly evaluated by modified total Sharp score (mTSS), however only small joints are assessed in this method. For the evaluation of large joints, we developed and validated a new radiographic scoring method (Assessment of Rheumatoid Arthritis by Scoring of Large Joint Destruction and Healing in Radiographic Imaging: ARASHI)1).
Objectives The purpose of this study is to evaluate the correlation of small joint damage and large joint damage using the the mTSS and the ARASHI scoring system in RA.
Methods “ARASHI status score” consists of 4 categories; joint space narrowing, erosion, joint surface destruction, and stability (total 0–16 points). “ARASHI change score” consists of 5 categories; porosis, joint space narrowing, erosion, joint surface destruction, and stability (total -11–12 points). Forty two patients (3 male, 39 women, mean age of 64.0 years old, mean disease duration of 12.3 years) who started treatment with abatacept were enrolled in this study. All patients fulfilled the ACR 1987 revised criteria. The joints with history of surgical intervention were excluded from this analysis, and the radiographic findings of 390 large joints (81 shoulders, 80 elbows, 79 hips, 69 knees and 81 ankle joints) were evaluated at baseline using the ARASHI status score, and assessed by the ARASHI change score at 1 year of abatacept therapy. We also evaluated mTSS of all patients at baseline and at 1 year of therapy, and the yearly change (ΔmTSS) was estimated. Correlation between mTSS and ARASHI score was evaluated by Sperman's rank correlation coefficient.
Results The mean values of mTSS and ARASHI status score at baseline were 105.9 (range: 0–417) and 1.002 (range: 0–12), respectively. At 1 year of abatacept therapy, the mean value of ΔmTSS was 0.9154 (range: -1–6) and the mean value of ARASHI change score was 0.1936 (range: -3–5). There was significant correlation between mTSS and ARASHI status score at baseline (r=0.4592, P<0.0001). On the other hand, there was no significant relationship between ΔmTSS and ARASHI change score (r=-0.0369, P=0.4750).
Conclusions We demonstrated a significant correlation between mTSS and ARASHI status score at baseline. This finding supports a general understanding that damage in small and large joints is correlated although the damage of large joints may have a later onset. In this study, however, there was no relationship between ΔmTSS and ARASHI change score at 1 year. It is possible that damage progression in small and large joints may not be highly correlated. Therefore, monitoring of both of small and large joint damage should be necessary to guide treatment for patients with RA.
Atsushi Kaneko, Isao Matsushita, Katsuaki Kanbe, Katsumitsu Arai, Yoshiaki Kuga, Asami Abe, Takeshi Matsumoto, Natsuko Nakagawa, Keiichiro Nishida. Development and validation of a new radiographic scoring system to evaluate bone and cartilage destruction and healing of large joints with rheumatoid arthritis: ARASHI (Assessment of rheumatoid arthritis by scoring of large joint destruction and healing in radiographic imaging) study. Mod Rheumatol 2013(23):1053-1062.
Disclosure of Interest None declared