Purpose: 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.
Patients and methods: In 293 RA patients enrolled in the KURAMA cohort, 28 joints were assessed by ultrasound.
Results: 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).
Conclusion: 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.
Keywords: Prognosis; Rheumatoid arthritis; Superb microvascular imaging; Ultrasonography.