Investigation of Inactive Disease States Among Patients With Juvenile Idiopathic Arthritis in the Childhood Arthritis and Rheumatology Research Alliance Registry.

OBJECTIVE: Inactive disease is the treatment goal for juvenile idiopathic arthritis (JIA), but there are multiple measures for disease activity. The objective was to compare individuals with JIA who meet different definitions for inactive disease. METHODS: Disease activity measures were determined at the 1-year follow-up visit for all patients with JIA enrolled in a North American multicenter registry from 2015 to 2019, the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry. Patient and disease characteristics between those who met only one composite definition of inactive disease were compared by χ2 for categorical variables and Wilcoxon rank sum for continuous variables. The Spearman correlation coefficient was calculated for simple disease measures. RESULTS: Among all 2904 patients with JIA enrolled in the CARRA Registry with 1-year visit data, 1984 (68%) had no active joints, 1485 (51%) had a physician global score of 0, 1366 (47%) had a patient/parent global score of 0, 1293 (45%) met the American College of Rheumatology provisional criteria for clinical inactive disease (ACR CID), and 1325 (46%) had a clinical Juvenile Arthritis Disease Activity Score (cJADAS10) of 1 or less. Almost half (47%) did not meet either composite definition of inactive disease, and 38% met both ACR CID and cJADAS10 of 1 or less. CONCLUSION: In a multicenter cohort of patients with JIA in North America, a large proportion of patients had inactive disease by single or composite measures after 1 year of observation in the Registry. There was significant overlap between patients who met ACR CID criteria and those who had a cJADAS10 of 1 or less. Additional studies are needed to evaluate the reasons for discordance in inactive disease measures.