Ultrasound is commonly used to assess the degree of synovitis in patients with rheumatoid arthritis (RA); however, it is unclear which joints are optimal for evaluating and predicting recurrence and remission.
In 293 RA patients enrolled in the KURAMA cohort, 28 joints were assessed by ultrasound.
Results from patients in remission in both 2015 and 2017 (Group 1, n = 152) were compared with those from patients in remission in 2015 and non-remission in 2017 (Group 2, n = 60). The SMI scores for total (3.1 vs. 6.3, P = 0.004), MCP2-5 (1.1 vs. 2.4, P = 0.03), wrist (0.9 vs. 2.1, P = 0.0003), MTP2-5 (0.4 vs. 1.0, P = 0.03), and Lisfranc joints (0.07 vs. 0.25, P = 0.04) were significantly higher for Group 2. When those in non-remission in 2015 and remission in 2017 (Group 3, n = 27) were compared with those in remission in 2015 and non-remission in both 2015 and 2017 (Group 4, n = 54), the GS-SMI combined score (3.0 vs. 5.0, P = 0.04) and SMI score (1.5 vs. 2.9, P = 0.04) for MCP2-5 joints were significantly higher for Group 4. Multivariate logistic regression analysis identified "wrist SMI score ≧ 1" as an independent prognostic factor for recurrence (odds ratio 3.08, P = 0.001) and "MCP2-5 GS-SMI combined score ≦ 4" as an independent prognostic factor for remission (odds ratio 3.25, P = 0.048).
We identified the optimal joint cut-off scores for predicting recurrence and remission in RA patients. Risk-stratification therapy based on the ultrasound scores may improve outcome and quality of life for patients with RA.