Bone mass predictors in a large cohort of children with juvenile idiopathic arthritis (JIA)

Methods The study population included 162 pts (113 F and 49 M, mean age 10.6 ± 3.1 yrs) affected with JIA: 77 oligoarticular, 48 polyarticular RF-, 15 systemic, and 22 enthesitisrelated arthritis (ERA) onset. All patients underwent bone mass evaluation by DXA at lumbar spine (L2–L4). DXA values were correlated with JIA category, age at onset, disease duration, ESR, CRP, flare rate, and medications. Ageand sex-specific reference values from an age-matched healthy population were used to calculate z-scores. Twoway analysis of variance was used to determine whether the DXA z-score correlated with disease category, medications, age at onset, disease duration.