Correlation between ultrasonographic scores and American college of rheumatology recommended rheumatoid arthritis disease activity measures: a systematic review and network meta-analysis

Background To validate and facilitate ultrasound examinations on rheumatoid arthritis (RA) disease activity measurements in routine clinical practice. Methods A systematic review and network meta-analysis (NMA) of ultrasound examinations on joints and its correlation with clinical RA disease activity was performed. PubMed, Embase and Cochrane library were searched for literatures published up to May 01st 2021. Bayesian random-effect NMA was conducted to pool the correlations of ultrasonographic assessment scores with composite RA disease activity measurements. Results Fifteen studies evaluating twelve different existing ultrasonographic measurements on joints evaluation for RA disease activity scoring were included in this NMA. For comparisons with clinical disease activity index and simplified disease activity index, synovitis gray scale ultrasound 7 joints (GSUS7) demonstrated modest correlation of 0.30[− 0.74, 1.23] and 0.46[− 0.45, 1.15] respectively, followed by synovitis power Doppler ultrasound 7 joints (PDUS7) (0.25[− 0.57, 1.14], 0.31[− 0.46, 1.24]) and power Doppler ultrasound 12 joints (PDUS12) (0.23[− 1.36, 0.83], 0.25[− 1.18, 0.88]). As for disease activity score using 28 joint counts, PDUS12 showed the biggest correlation of 0.53[− 0.09, 1.11], followed by ultrasound 7 joints (US7) (0.50[0.06, 0.93]), PDUS7 (0.49[− 0.24, 1.12]), power Doppler ultrasound 6 joints (PDUS6) (0.42[− 0.29, 1.21]), synovitis PDUS7 (0.47[− 0.09, 1.27]) and synovitis GSUS7 (0.40[0.01, 0.86]). Conclusion Comparative validity was observed on fewer joints ultrasonic evaluation for RA disease activity measurements, such as synovitis GSUS7 and synovitis PDUS7. Ultrasonographic measurements can be complementary for clinical RA disease activity measures with clinical efficiency, and technical guidelines were in need for clinical routine practice.