Modified Juvenile Spondyloarthritis Disease Activity Index in the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry

• Published in: Journal of rheumatology Vol. 50; no. 4; p. 532
• Main Authors: Srinivasalu, Hemalatha, Treemarcki, Erin Brennan, Rumsey, Dax G, Weiss, Pamela F, Colbert, Robert A
• Format: Journal Article
• Language: English
• Published: Canada 01.04.2023
• Subjects: Adolescent; Arthritis, Juvenile - diagnosis; C-Reactive Protein; Child; Female; Humans; Male; Registries; Rheumatology; Severity of Illness Index; Spondylarthritis - diagnosis; juvenile idiopathic arthritis; spondyloarthropathy; disease activity score
• ISSN: 1499-2752
• DOI: 10.3899/jrheum.220509

To validate the Juvenile Spondyloarthritis Disease Activity Index (JSpADA), and modified versions thereof, in a North American cohort of patients with enthesitis-related arthritis (ERA). We utilized the Childhood Arthritis and Rheumatology Research Alliance Registry database ERA cohort to validate the JSpADA and its modifications (JSpADA6-no Schober, no C-reactive protein [CRP]/erythrocyte sedimentation rate [ESR]; JSpADA7-no Schober; and JSpADA7-no CRP/ESR) using the Outcome Measures in Rheumatology principles of face validity, discriminative validity, and responsiveness to change. There were 51 subjects (64 visits) with complete JSpADA data with a mean age of 13.7 years and disease duration of 30.9 months. Subjects were predominantly White (84.3%), and 56.9% were male and 50% were HLA-B27 positive. The JSpADA showed high correlation with the clinical 10-joint Juvenile Arthritis Disease Activity Score (cJADAS10; = 0.81), moderate-to-high correlation with physician global assessment (PGA; = 0.69), and low-to-fair correlation with Childhood Health Assessment Questionnaire (CHAQ; = 0.22). The modifications of the JSpADA (JSpADA7-no Schober; JSpADA7-no CRP/ESR; and JSpADA6-no Schober, no CRP/ESR) performed similarly with high correlation with cJADAS10 ( = 0.81, 0.79, and 0.80, respectively), moderate-to-high correlation with PGA ( = 0.65, 0.67, 0.64, respectively), and low-to-fair correlation with CHAQ ( = 0.35, 0.34, 0.39, respectively). All modified versions of JSpADA had good responsiveness to change. All versions of JSpADA had excellent discriminative validity. We propose the term for the modification of JSpADA with 6 elements (JSpADA6-no Schober, no CRP/ESR). This shorter disease activity index may improve implementation of JSpADA in both clinical practice and research trials.