Body composition and adipokines in patients with juvenile idiopathic arthritis and systemic glucocorticoids

The aim of this cross-sectional study was to explore body composition, and the relationship of serum adipokines with bone mass and disease activity, in a cohort of JIA patients with at least three months' exposure to systemic glucocorticoids (GC).

Fifty patients with JIA (34 girls, median age 12.4 years and disease duration 6.3 years) and 88 controls matched for gender and age participated in this study. Bone mineral content (BMC) and areal bone mineral density (BMD) of the lumbar spine and whole body, as well as body composition were assessed with dual-energy x-ray absorptiometry. Fasting serum leptin and adiponectin were measured.

Fat and lean mass were similar between patients and controls, but patients had slightly decreased BMD Z-scores. Serum leptin and adiponectin concentrations were similar. Disease activity was low, and no correlation with adipokines was observed. Patients with bone age-corrected lumbar spine BMD Z-score ≤-1.0 ("low BMD") did not show alterations in body composition, GC exposure or current disease activity, but had decreased BMC-to-lean mass ratio (p<0.001) and tendency for increased serum leptin (p=0.064). However, no association of leptin with BMD in multivariate analysis existed in patients or controls. An inverse association between adiponectin and whole body BMD was observed in both groups.

Normal body composition was observed in a JIA cohort with low-dose GC exposure. Patients with "low BMD" tended to have increased serum leptin, but leptin did not associate with BMD. In this cohort with low disease activity, no correlation between adipokines and disease activity was present.