Timing matters: real-world effectiveness of early combination of biologic and conventional synthetic disease-modifying antirheumatic drugs for treating newly diagnosed polyarticular course juvenile idiopathic arthritis.

OBJECTIVES: To compare real-world effectiveness of two adaptive treatment strategies of disease-modifying antirheumatic drugs (DMARDs) in treating children with newly diagnosed polyarticular course juvenile idiopathic arthritis (pcJIA): early aggressive use of biologic DMARDs (bDMARDs) in combination with conventional synthetic DMARDs (csDMARDs) versus conservative delayed use of bDMARDs following the initial csDMARD prescription. METHODS: A single-centre newly diagnosed DMARD-naive pcJIA patient database (n=465) was derived from the electronic medical records between 1 January 2009 and 31 December 2018. The primary study endpoints were clinical Juvenile Arthritis Disease Activity Score (cJADAS) at 6 and 12 months following the first DMARD prescription. The secondary study endpoint was Pediatric Quality of Life Inventory (PedsQL) generic total score at 12 months. Averaged causal treatment effects were assessed using a Bayesian non-parametric casual inference method. RESULTS: Both cJADAS and PedsQL improve over time, regardless of the treatment strategies. Compared with the conservative approach, early aggressive approach is more effective in reducing cJADAS (mean -2.17, 95% CI -3.77 to -0.56) by 6 months. Adding bDMARD after 6 months to the initial treatment provides very little added benefit. The averaged treatment effect was 6.35 (95% CI -5.89 to 18.58) improvement in PedsQL at 12 months. CONCLUSIONS: Timing matters-early aggressive use with bDMARDs is more effective than conservative delayed treatment in lowering disease activity after 6 and 12 months of treatment.

Intra-rater and inter-rater reliability of the 10-point Manual Muscle Test (MMT) of strength in children with juvenile idiopathic inflammatory myopathies (JIIM).

OBJECTIVE: Children with juvenile idiopathic inflammatory myopathies (JIIM) present with muscle inflammation and decreased strength that may affect their functional abilities. The purpose of this study was to determine the intra-rater and inter-rater reliability of the 0 to 10-point manual muscle testing method for children with JIIM. METHODS: For the intra-rater and inter-rater reliability studies, 10 and 9 children with JIIM participated, respectively. For intra-rater reliability, one pediatric therapist completed two assessments in one day with a one-hour break. For inter-rater reliability, four therapists assessed the same child within a single morning. RESULTS: Spearman correlations for intra-rater reliability ranged from 0.70 to 1.00. Kendall's W coefficient for inter-rater reliability of groups of muscles (total, proximal, distal, and peripheral) ranged from 0.51 to 0.76. CONCLUSIONS: The total, proximal, and peripheral Manual Muscle Test (MMT) score, using the 0-10 point scale, has acceptable reliability in JIIM patients.