American College of Rheumatology Develops New Juvenile Arthritis Disease Activity Score Cutoffs for Disease Activity States in JIA

The American College of Rheumatology (ACR) developed and validated new cutoffs for Juvenile Arthritis Disease Activity Score 10 (JADAS10) and clinical JADAS10 (cJADAS10) to identify the different disease activity states in children with oligoarthritis and rheumatoid factor (RF)-negative polyarthritis, according to a report published in Arthritis & Rheumatology.

Patients were selected from the multinational Epidemiology, Treatment, and Outcome of Childhood Arthritis (EPOCA) study, which included physicians’ subjective assessments of disease status, defined as inactive disease, minimal disease activity, moderate disease activity, and high disease activity. The definition cohort included 1936 patients. To identify the cutoffs, researchers used percentile mapping, Youden index, 90% fixed specificity, and evaluation of agreement. The validation cohort included 4014 patients from the EPOCA study, longitudinal data from 2 randomized clinical trials, and 88 patients from PharmaChild, a multinational registry to assess safety and efficacy of medications in children with juvenile idiopathic arthritis (JIA).

The JADAS10 cutoffs for inactive disease, minimal disease activity, moderate disease activity were 1.4, 4, and 13, respectively, for oligoarthritis and 2.7, 6, and 17, respectively, for polyarthritis. The cJADAS10 cutoffs were 1.1, 4, and 12, respectively, for oligoarthritis and 2.5, 5, and 16, respectively, for polyarthritis.

The new cutoffs were able to distinguish between different disease severity statuses and response in clinical trials. The cutoffs also predicted disease remission at 2 years in patients who achieved inactive disease or minimal disease activity during the first year of observation.

Limitations of the study included a lack of standardization in assessing disease states, inability to apply results of the analysis to different categories of JIA beyond oligoarthritis and RF-negative polyarthritis, and a small sample size for parts of the validation analysis.

The researchers concluded, “We have developed a new set of JADAS10 and cJADAS10 cutoffs for the different disease activity states in JIA, which were based on the subjective perception of the level of disease activity by a multinational sample of pediatric rheumatologists. In validation analyses, the cutoffs demonstrated a strong ability to discriminate between different levels of disease severity and treatment response and to predict the achievement of long-term disease remission.”

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.

Reference

Trincianti C, Van Dijkhuizen EHP, Alongi A, et al. for the Paediatric Rheumatology International Trials Organization. Definition and validation of the American College of Rheumatology 2021 Juvenile Arthritis Disease Activity Score cutoffs for disease activity states in juvenile idiopathic arthritis. Arthritis Rheumatol. Published online September 28, 2021. doi:10.1002/art.41879