We compared the change in joint inflammation and the proportion of subjects achieving threshold levels of improvement using the existing methods employing ultrasonography on pre-determined joint sites versus novel methods. These novel methods select the most affected joints based on (i) ultrasonography-the Individualized-Ultrasound (IUS) method, or (ii) ultrasonography and clinical joint assessment-the individualized-Composite-Ultrasound (ICUS) method. Mean 3-month change in total inflammation score (ΔTIS) and 95% CI was computed for each method on 24 RA subjects initiated or escalated on treatment. Individual improvement in TIS per subject, calculated as the 3-month ΔTIS divided by the maximum possible TIS score expressed as a percentage, was used to obtain the proportion of subjects achieving response across improvement categories. Mean 3-month ΔTIS was significantly greater (p values ranging from 0.0003 to 0.0026) for novel versus existing methods using 12- and 7-joint approaches. Using 12-joint approach, percentages of subjects in improvement categories ≥5%, ≥10%, ≥15% and ≥20% were, respectively, 50, 37.5, 12.5 and 8.3% for IUS; 58.3, 37.5, 12.5 and 8.3% for ICUS; and 16.7, 0, 0 and 0% for the existing method. Using 7-joint approach, the respective category percentages were 62.5, 37.5, 25 and 12.5% for IUS; 62.5, 41.7, 16.7 and 8.3% for ICUS; and 12.5, 4.2, 4.2 and 0% for the existing method. Novel ultrasound methods are more likely to detect improvement in joint inflammation, with more subjects achieving response across improvement categories, thereby representing a substantial advantage over the existing methods. However, this requires confirmation in larger RA cohorts.
Keywords: Joints; Rheumatoid Arthritis; Synovitis; Ultrasonography.