Definition and Validation of the American College of Rheumatology 2021 Juvenile Arthritis Disease Activity Score Cutoffs for Disease Activity States in Juvenile Idiopathic Arthritis.

OBJECTIVE: To develop and validate new Juvenile Arthritis Disease Activity Score 10 (JADAS10) and clinical JADAS10 (cJADAS10) cutoffs to separate the states of inactive disease (ID), minimal disease activity (MiDA), moderate disease activity (MoDA), and high disease activity (HDA) in children with oligoarthritis and with rheumatoid factor-negative polyarthritis, based on subjective disease assessment by the treating pediatric rheumatologist. METHODS: The cutoffs definition cohort was composed of 1,936 patients included in the multinational Epidemiology, Treatment and Outcome of Childhood Arthritis (EPOCA) study. Using the subjective physician rating as an external criterion, 4 methods were applied to identify the cutoffs: mapping, Youden index, 90% specificity, and maximum agreement. The validation cohort included 4,014 EPOCA patients, patients from 2 randomized trials, and 88 patients from the PharmaChild registry. Cutoff validation was conducted by assessing discriminative and predictive ability. RESULTS: The JADAS10 cutoffs 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 cutoffs discriminated strongly among different levels of pain and morning stiffness, between patients who were and those who were not prescribed a new medication, and between different levels of improvement in clinical trials. Achievement of ID and MiDA according to the new JADAS cutoffs at least twice in the first year of disease predicted better outcome at 2 years. CONCLUSION: The 2021 JADAS and cJADAS cutoffs revealed good metrologic properties in both definition and validation samples, and are therefore suitable for use in clinical trials and routine practice.

Phenotypic variability and disparities in treatment and outcomes of childhood arthritis throughout the world: an observational cohort study.

BACKGROUND: To our knowledge, the characteristics and burden of childhood arthritis have never been studied on a worldwide basis. We aimed to investigate, with a cross-sectional study, the prevalence of disease categories, treatment methods, and disease status in patients from across different geographical areas and from countries with diverse wealth status. METHODS: In this multinational, cross-sectional, observational cohort study, we asked international paediatric rheumatologists from specialised centres to enrol children with a diagnosis of juvenile idiopathic arthritis, according to International League of Associations for Rheumatology criteria, who were seen consecutively for a period of 6 months. Each patient underwent retrospective and cross-sectional assessments, including measures of disease activity and damage and questionnaires on the wellbeing and quality of life of the children. We qualitatively compared the collected data across eight geographical areas, and we explored an association between disease activity and damage and a country's gross domestic product (GDP) with a multiple logistic regression analysis. FINDINGS: Between April 4, 2011, and Nov 21, 2016, 9081 patients were enrolled at 130 centres in 49 countries, grouped into eight geographical areas. Systemic arthritis (125 [33·0%] of 379 patients) and enthesitis-related arthritis (113 [29·8%] of 379) were more common in southeast Asia, whereas oligoarthritis was more prevalent in southern Europe (1360 [56·7%] of 2400) and rheumatoid factor-negative polyarthritis was more frequent in North America (165 [31·5%] of 523) than in the other areas. Prevalence of uveitis was highest in northern Europe (161 [19·1%] of 845 patients) and southern Europe (450 [18·8%] of 2400) and lowest in Latin America (54 [6·4%] of 849), Africa and Middle East (71 [5·9%] of 1209), and southeast Asia (19 [5·0%] of 379). Median age at disease onset was lower in southern Europe (3·5 years, IQR 1·9-7·3) than in other regions. Biological, disease-modifying antirheumatic drugs were prescribed more frequently in northern Europe and North America than in other geographical settings. Patients living in countries with lower GDP had greater disease activity and damage than those living in wealthier countries. Damage was associated with referral delay. INTERPRETATION: Our study documents a variability in prevalence of disease phenotypes and disparities in therapeutic choices and outcomes across geographical areas and wealth status of countries. The greater disease burden in lower-resource settings highlights the need for public health efforts aimed at improving equity in access to effective treatments and care for juvenile idiopathic arthritis. FUNDING: IRCCS Istituto Giannina Gaslini.

Intra-articular corticosteroids versus intra-articular corticosteroids plus methotrexate in oligoarticular juvenile idiopathic arthritis: a multicentre, prospective, randomised, open-label trial.

BACKGROUND: Little evidence-based information is available to guide the treatment of oligoarticular juvenile idiopathic arthritis. We aimed to investigate whether oral methotrexate increases the efficacy of intra-articular corticosteroid therapy. METHODS: We did this prospective, open-label, randomised trial at ten hospitals in Italy. Using a concealed computer-generated list, children younger than 18 years with oligoarticular-onset disease were randomly assigned (1:1) to intra-articular corticosteroids alone or in combination with oral methotrexate (15 mg/m2; maximum 20 mg). Corticosteroids used were triamcinolone hexacetonide (shoulder, elbow, wrist, knee, and tibiotalar joints) or methylprednisolone acetate (ie, subtalar and tarsal joints). We did not mask patients or investigators to treatment assignments. Our primary outcome was the proportion of patients in the intention-to-treat population who had remission of arthritis in all injected joints at 12 months. This trial is registered with European Union Clinical Trials Register, EudraCT number 2008-006741-70. FINDINGS: Between July 7, 2009, and March 31, 2013, we screened 226 participants and randomly assigned 102 to intra-articular corticosteroids alone and 105 to intra-articular corticosteroids plus methotrexate. 33 (32%) patients assigned to intra-articular corticosteroids alone and 39 (37%) assigned to intra-articular corticosteroids and methotrexate therapy had remission of arthritis in all injected joints (p=0·48). Adverse events were recorded for 20 (17%) patients who received methotrexate, which led to permanent treatment discontinuation in two patients (one due to increased liver transaminases and one due to gastrointestinal discomfort). No patient had a serious adverse event. INTERPRETATION: Concomitant administration of methotrexate did not augment the effectiveness of intra-articular corticosteroid therapy. Future studies are needed to define the optimal therapeutic strategies for oligoarticular juvenile idiopathic arthritis. FUNDING: Italian Agency of Drug Evaluation.

Prediction of methotrexate intolerance in juvenile idiopathic arthritis: a prospective, observational cohort study.

BACKGROUND: Methotrexate (MTX) is an effective and safe drug in the treatment of juvenile idiopathic arthritis (JIA). Despite its safety, MTX-related gastrointestinal adverse effects before and after MTX administration, termed MTX intolerance, occur frequently, leading to non-compliance and potentially premature MTX termination. The aim of this study was to construct a risk model to predict MTX intolerance. METHODS: In a prospective JIA cohort, clinical variables and single nucleotide polymorphisms were determined at MTX start. The Methotrexate Intolerance Severity Score was employed to measure MTX intolerance in the first year of treatment. MTX intolerance was most prevalent at 6 or 12 months after MTX start, which was defined as the outcome for the prediction model. The model was developed in 152 patients using multivariable logistic regression analysis and subsequently internally validated using bootstrapping. RESULTS: The prediction model included the following predictors: JIA category, antinuclear antibody, parent/patient assessment of pain, Juvenile Arthritis Disease Activity Score-27, thrombocytes, alanine aminotransferase and creatinine. The model classified 77.5% of patients correctly, and 66.7% of patients after internal validation by bootstrapping. The lowest predicted risk of MTX intolerance was 18.9% and the highest predicted risk was 85.9%. The prediction model was transformed into a risk score (range 0-17). At a cut-off of ≥6, sensitivity was 82.0%, specificity 56.1%, positive predictive value was 58.7% and negative predictive value 80.4%. CONCLUSIONS: This clinical prediction model showed moderate predictive power to detect MTX intolerance. To develop into a clinically usable tool, it should be validated in an independent cohort and updated with new predictors. Such an easy-to-use tool could then assist clinicians in identifying patients at risk to develop MTX intolerance, and in turn to monitor them closely and intervene timely in order to prevent the development of MTX intolerance. TRIAL REGISTRATION: ISRCTN register, www.isrctn.com, ISRCTN13524271.