title: Physical activity in children with Juvenile Idiopathic Arthritis compared to controls.
abstract: BACKGROUND
  To compare physical activity (PA) in children with juvenile idiopathic arthritis (JIA) with controls and to analyse the effect of disease specific factors on PA in children with JIA treated according to current treatment regimes.
  
  
  METHODS
  PA was measured with a 7-day activity diary and expressed as physical activity level (PAL). Moderate to vigorous physical activity (MVPA) (hours/day) and sedentary time (hours/day) was determined. In children with JIA, medication, the number of swollen and/or painful joints, disease activity, functional ability, pain and well-being was determined. Multivariate regression analysis was performed to analyze differences in PA between JIA and controls, adjusted for influences of age, gender, season, Body Mass Index (BMI) and to analyze predictors of PA in JIA patients.
  
  
  RESULTS
  Seventy-six children with JIA (26 boys and 50 girls, mean ± SD age 10.0 ± 1.4 years) and 131 controls (49 boys and 82 girls, mean ± SD age 10.4 ± 1.2 years) participated in this study. Children with JIA had a significantly lower PAL (0.10, p = 0.01) corrected for age, BMI, gender and season. They spent less time in MVPA (0.41 h/day, p = 0.06) and had a significantly higher mean time spent in sedentary activities (0.59 h/day, p 0.02) compared to controls. The activity level of children with JIA was related to age, gender, season, feeling of well-being and pain.
  
  
  CONCLUSIONS
  Children with JIA have a lower PAL, spent less time in MVPA and spent more time on sedentary activities compared to controls despite current medical treatment and PA encouragement.
  
  
  BACKGROUND
  Data of the children with JIA are from the Rheumates@work study ISRCTN92733069 .
authors.affiliation: Department of Rehabilitation Medicine, University of Groningen, University Medical Center Groningen, PO Box 30001, 9700 RB, Groningen, The Netherlands. g.j.f.j.bos@umcg.nl.
authors.forename: G J F Joyce
authors.initials: GJ
authors.lastname: Bos
authors.affiliation: Department of Rehabilitation Medicine, University of Groningen, University Medical Center Groningen, PO Box 30001, 9700 RB, Groningen, The Netherlands.
authors.forename: Otto T H M
authors.initials: OT
authors.lastname: Lelieveld
authors.affiliation: Department of Pediatric Rheumatology, University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, PO Box 30001, 9700 RB, Groningen, The Netherlands.
authors.forename: Wineke
authors.initials: W
authors.lastname: Armbrust
authors.affiliation: University of Groningen, University Medical Center Groningen, Beatrix Children's Hospital, PO Box 30001, 9700 RB, Groningen, The Netherlands.
authors.forename: Pieter J J
authors.initials: PJ
authors.lastname: Sauer
authors.affiliation: Department of Rehabilitation Medicine, University of Groningen, University Medical Center Groningen, PO Box 30001, 9700 RB, Groningen, The Netherlands.
authors.forename: Jan H B
authors.initials: JH
authors.lastname: Geertzen
authors.affiliation: Department of Rehabilitation Medicine, University of Groningen, University Medical Center Groningen, PO Box 30001, 9700 RB, Groningen, The Netherlands.|Department of Oral and Maxillofacial Surgery, University of Groningen, University Medical Center Groningen, PO Box 30001, 9700 RB, Groningen, The Netherlands.
authors.forename: Pieter U
authors.initials: PU
authors.lastname: Dijkstra
mesh_terms: D000203:Activities of Daily Living; D001171:Arthritis, Juvenile; D016022:Case-Control Studies; D002648:Child; D015444:Exercise; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D009426:Netherlands; D010147:Pain Measurement; D012044:Regression Analysis; D012720:Severity of Illness Index
keywords: Juvenile idiopathic arthritis; Physical activity; Physical activity level