Costs of medication use among patients with juvenile idiopathic arthritis in the Dutch healthcare system.

Background: This study aims to quantify medication costs in juvenile idiopathic arthritis (JIA), based on subtype.Research design and methods: This study is a single-center, retrospective analysis of prospective data from electronic medical records of JIA patients, aged 0-18 years between 1 April 2011 and 31 March 2019. Patient characteristics (age, gender, subtype) and medication use were extracted. Medication use and costs were reported as: 1) mean total annual costs; 2) between-patient heterogeneity in these costs; 3) duration of medication use; and, 4) costs over the treatment course.Results: The analysis included 691 patients. Mean total medication costs were €2,103/patient/year, including €1,930/patient/year (91.8%) spent on biologicals. Costs varied considerably between subtypes, with polyarticular rheumatoid-factor positive and systemic JIA patients having the highest mean costs (€5,020/patient/year and €4,790/patient/year, respectively). Mean annual medication costs over the patient's treatment course ranged from <€1,000/year (71.1% of patients) to >€11,000/year (2.5% of patients). Etanercept and adalimumab were the most commonly used biologicals. Cost fluctuations over the treatment course were primarily attributable to biological use.Conclusions: Polyarticular rheumatoid-factor positive and systemic JIA patients had the highest mean total annual medication costs, primarily attributable to biologicals. Costs varied considerably between subtypes, individuals, and over the treatment course.

2016 American College of Rheumatology/European League Against Rheumatism Criteria for Minimal, Moderate, and Major Clinical Response in Juvenile Dermatomyositis: An International Myositis Assessment and Clinical Studies Group/Paediatric Rheumatology International Trials Organisation Collaborative Initiative.

To develop response criteria for juvenile dermatomyositis (DM). We analysed the performance of 312 definitions that used core set measures from either the International Myositis Assessment and Clinical Studies Group (IMACS) or the Paediatric Rheumatology International Trials Organisation (PRINTO) and were derived from natural history data and a conjoint analysis survey. They were further validated using data from the PRINTO trial of prednisone alone compared to prednisone with methotrexate or cyclosporine and the Rituximab in Myositis (RIM) trial. At a consensus conference, experts considered 14 top candidate criteria based on their performance characteristics and clinical face validity, using nominal group technique. Consensus was reached for a conjoint analysis-based continuous model with a total improvement score of 0-100, using absolute per cent change in core set measures of minimal (≥30), moderate (≥45), and major (≥70) improvement. The same criteria were chosen for adult DM/polymyositis, with differing thresholds for improvement. The sensitivity and specificity were 89% and 91-98% for minimal improvement, 92-94% and 94-99% for moderate improvement, and 91-98% and 85-86% for major improvement, respectively, in juvenile DM patient cohorts using the IMACS and PRINTO core set measures. These criteria were validated in the PRINTO trial for differentiating between treatment arms for minimal and moderate improvement (p=0.009-0.057) and in the RIM trial for significantly differentiating the physician's rating for improvement (p<0.006). The response criteria for juvenile DM consisted of a conjoint analysis-based model using a continuous improvement score based on absolute per cent change in core set measures, with thresholds for minimal, moderate, and major improvement.

2016 American College of Rheumatology/European League Against Rheumatism Criteria for Minimal, Moderate, and Major Clinical Response in Juvenile Dermatomyositis: An International Myositis Assessment and Clinical Studies Group/Paediatric Rheumatology International Trials Organisation Collaborative Initiative.

OBJECTIVE: To develop response criteria for juvenile dermatomyositis (DM). METHODS: We analyzed the performance of 312 definitions that used core set measures from either the International Myositis Assessment and Clinical Studies Group (IMACS) or the Paediatric Rheumatology International Trials Organisation (PRINTO) and were derived from natural history data and a conjoint analysis survey. They were further validated using data from the PRINTO trial of prednisone alone compared to prednisone with methotrexate or cyclosporine and the Rituximab in Myositis (RIM) trial. At a consensus conference, experts considered 14 top candidate criteria based on their performance characteristics and clinical face validity, using nominal group technique. RESULTS: Consensus was reached for a conjoint analysis-based continuous model with a total improvement score of 0-100, using absolute percent change in core set measures of minimal (≥30), moderate (≥45), and major (≥70) improvement. The same criteria were chosen for adult DM/polymyositis, with differing thresholds for improvement. The sensitivity and specificity were 89% and 91-98% for minimal improvement, 92-94% and 94-99% for moderate improvement, and 91-98% and 85-86% for major improvement, respectively, in juvenile DM patient cohorts using the IMACS and PRINTO core set measures. These criteria were validated in the PRINTO trial for differentiating between treatment arms for minimal and moderate improvement (P = 0.009-0.057) and in the RIM trial for significantly differentiating the physician's rating for improvement (P < 0.006). CONCLUSION: The response criteria for juvenile DM consisted of a conjoint analysis-based model using a continuous improvement score based on absolute percent change in core set measures, with thresholds for minimal, moderate, and major improvement.