title: Urinary concentration of 8-isoprostane as marker of severity of pediatric OSAS.
abstract: BACKGROUND
  F2-isoprostanes are considered to be a reliable standard biomarker of oxidative stress in vivo because they are not influenced by the intake of lipids in the diet, and they are chemically stable molecules and easily detected. This study aimed to test the hypothesis that 8-isoprostane level is a useful marker to valuate the severity of pediatric obstructive sleep apnea (OSA).
  
  
  METHODS
  Sixty-five children with sleep-disordered breathing (SDB) (mean age 5.9±2.0 years; 63.1% males) were recruited. The urine sample for the measurement of 8-isoprostane was collected the morning after the polysomnographic recording. Children were divided into two groups according to their apnea-hypopnea index (AHI).
  
  
  RESULTS
  Urinary 8-isoprostane levels positively correlated with the sleep clinical record score (r=0.38, p=0.002) and AHI (r=0.24, p=0.05) and negatively correlated with age (r=-0.36, p=0.003) and body surface area (r=-0.38, p=0.002). Urinary 8-isoprostane levels were significantly higher in the group with AHI of ≥5 events (ev)/h than in the group with AHI of <5 ev/h (p<0.01).
  
  
  CONCLUSIONS
  Urinary 8-isoprostane may be used as a specific inflammatory marker to predict the severity of OSA; this method has the advantage of being noninvasive and easy to use in both compliant and noncompliant children.
authors.affiliation: Neuroscience, Mental Health and Sense Organs Department, Sleep Disorder Centre, Faculty of Medicine and Psychology, "La Sapienza" University, Rome, Italy, mariapia.villa@uniroma1.it.
authors.forename: Maria Pia
authors.initials: MP
authors.lastname: Villa
authors.forename: Maria Chiara
authors.initials: MC
authors.lastname: Supino
authors.forename: Susanna
authors.initials: S
authors.lastname: Fedeli
authors.forename: Jole
authors.initials: J
authors.lastname: Rabasco
authors.forename: Ottavio
authors.initials: O
authors.lastname: Vitelli
authors.forename: Marco
authors.initials: M
authors.lastname: Del Pozzo
authors.forename: Giovanna
authors.initials: G
authors.lastname: Gentile
authors.forename: Luana
authors.initials: L
authors.lastname: Lionetto
authors.forename: Mario
authors.initials: M
authors.lastname: Barreto
authors.forename: Maurizio
authors.initials: M
authors.lastname: Simmaco
mesh_terms: D015415:Biomarkers / Q000652:urine*; D002648:Child; D002675:Child, Preschool; D015237:Dinoprost / Q000031:analogs & derivatives* / Q000652:urine; D005260:Female; D006801:Humans; D008297:Male; D018384:Oxidative Stress / Q000502:physiology; D017286:Polysomnography; D011237:Predictive Value of Tests; D012016:Reference Values; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis* / Q000652:urine*
chemical_list: D015415:Biomarkers; C075750:8-epi-prostaglandin F2alpha; D015237:Dinoprost