title: Increased carotid artery intima-media thickness and myeloperoxidase level in children with newly diagnosed juvenile idiopathic arthritis.
abstract: BACKGROUND
  Juvenile idiopathic arthritis (JIA) is a frequent childhood rheumatic disease characterized by chronic inflammation. The latter has been related to impairment of arterial functional-structural properties, atherogenesis and later cardiovascular events. The objective of this study was to examine intima-media thickness (IMT) and the parameters of arterial stiffness in children with JIA at diagnosis and their correlation with JIA subtype and markers of inflammation and atherosclerosis.
  
  
  METHODS
  Thirty-nine newly diagnosed patients with JIA (26 girls; mean age, 13.2 ± 2.6 years) and 27 healthy controls (9 girls; mean age, 13.6 ± 3.4 years) were included in the study. Twelve patients had oligoarthritis, fifteen had extended oligoarthritis and twelve had rheumatoid factor-negative polyarthritis. IMT of the common carotid artery was determined by ultrasonography, carotid-femoral pulse wave velocity (cfPWV) and augmentation index adjusted to a heart rate of 75 beats/min (AIx@75) were determined by applanation tonometry. The serum levels of atherosclerosis-related biomarkers, such as asymmetric dimethylarginine (ADMA), myeloperoxidase (MPO) and adiponectin, were measured by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Mean IMT (0.46 ± 0.04 vs. 0.42 ± 0.04 mm; p = 0.0003) and MPO concentration (115.2 [95% confidence interval {95% CI}, 97.4-136.3] vs. 57.6 [95% CI, 47.1-70.3] ng/ml; p < 0.0001) were higher in the patients with JIA than in the control subjects. The cfPWV, AIx@75 and serum ADMA and adiponectin levels did not significantly differ between the groups and JIA subtypes. Serum adiponectin level correlated negatively with AIx@75 in patients with JIA (r = -0.38; p < 0.05).
  
  
  CONCLUSIONS
  Patients with JIA have increased mean IMT and elevated MPO levels at early stages of the disease. AIx@75 was inversely independently associated with adiponectin level in the patients, suggesting that lower adiponectin levels might influence arterial subclinical stiffening in patients with newly diagnosed JIA.
authors.affiliation: Department of Paediatrics, Faculty of Medicine, University of Tartu, Lunini 6, Tartu, 51014, Estonia. jaanika.ilisson@kliinikum.ee.|Children's Clinic, Tartu University Hospital, Tartu, Estonia. jaanika.ilisson@kliinikum.ee.
authors.forename: Jaanika
authors.initials: J
authors.lastname: Ilisson
authors.affiliation: Department of Biochemistry, Institute of Biomedicine and Translational Medicine, The Centre of Excellence for Translational Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia. maksimzagura@gmail.com.|Department of Cardiology, Faculty of Medicine, University of Tartu, Tartu, Estonia. maksimzagura@gmail.com.
authors.forename: Maksim
authors.initials: M
authors.lastname: Zagura
authors.affiliation: Department of Biochemistry, Institute of Biomedicine and Translational Medicine, The Centre of Excellence for Translational Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia. kersti.zilmer@ut.ee.
authors.forename: Kersti
authors.initials: K
authors.lastname: Zilmer
authors.affiliation: Department of Cardiology, Faculty of Medicine, University of Tartu, Tartu, Estonia. erik.salum@gmail.com.
authors.forename: Erik
authors.initials: E
authors.lastname: Salum
authors.affiliation: Department of Paediatrics, Faculty of Medicine, University of Tartu, Lunini 6, Tartu, 51014, Estonia. kaire.heilman@lastekliinik.ee.|Tallinn Children's Hospital, Tallinn, Estonia. kaire.heilman@lastekliinik.ee.
authors.forename: Kaire
authors.initials: K
authors.lastname: Heilman
authors.affiliation: Department of Biochemistry, Institute of Biomedicine and Translational Medicine, The Centre of Excellence for Translational Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia. anneli.piir@ut.ee.
authors.forename: Anneli
authors.initials: A
authors.lastname: Piir
authors.affiliation: Department of Paediatrics, Faculty of Medicine, University of Tartu, Lunini 6, Tartu, 51014, Estonia. vallo.tillmann@kliinikum.ee.|Children's Clinic, Tartu University Hospital, Tartu, Estonia. vallo.tillmann@kliinikum.ee.
authors.forename: Vallo
authors.initials: V
authors.lastname: Tillmann
authors.affiliation: Department of Biochemistry, Institute of Biomedicine and Translational Medicine, The Centre of Excellence for Translational Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia. jaak.kals@kliinikum.ee.|Department of Vascular Surgery, Tartu University Hospital, Tartu, Estonia. jaak.kals@kliinikum.ee.
authors.forename: Jaak
authors.initials: J
authors.lastname: Kals
authors.affiliation: Department of Biochemistry, Institute of Biomedicine and Translational Medicine, The Centre of Excellence for Translational Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia. mihkel.zilmer@ut.ee.
authors.forename: Mihkel
authors.initials: M
authors.lastname: Zilmer
authors.affiliation: Department of Paediatrics, Faculty of Medicine, University of Tartu, Lunini 6, Tartu, 51014, Estonia. chris.pruunsild@kliinikum.ee.|Children's Clinic, Tartu University Hospital, Tartu, Estonia. chris.pruunsild@kliinikum.ee.
authors.forename: Chris
authors.initials: C
authors.lastname: Pruunsild
mesh_terms: D000293:Adolescent; D001171:Arthritis, Juvenile / Q000097:blood* / Q000175:diagnosis* / Q000201:enzymology; D015415:Biomarkers / Q000097:blood; D059168:Carotid Intima-Media Thickness / Q000639:trends; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009195:Peroxidase / Q000097:blood*
chemical_list: D015415:Biomarkers; D009195:Peroxidase