title: Time course of EEG slow-wave activity in pre-school children with sleep disordered breathing: a possible mechanism for daytime deficits?
abstract: BACKGROUND
  Daytime deficits in children with sleep disordered breathing (SDB) are theorized to result from hypoxic insult to the developing brain or fragmented sleep. Yet, these do not explain why deficits occur in primary snorers (PS). The time course of slow wave EEG activity (SWA), a proxy of homeostatic regulation and cortical maturation, may provide insight.
  
  
  METHODS
  Clinical and control subjects (N=175: mean age 4.3±0.9 y: 61% male) participated in overnight polysomnography (PSG). Standard sleep scoring and power spectral analyses were conducted on EEG (C4/A1; 0.5-<3.9Hz). Univariate ANOVA's evaluated group differences in sleep stages and respiratory parameters. Repeated-measures ANCOVA evaluated group differences in the time course of SWA.
  
  
  RESULTS
  Four groups were classified: controls (OAHI ≤ 1 event/h; no clinical history); PS (OAHI ≤ 1 event/h; clinical history); mild OSA (OAHI=1-5 events/h); and moderate to severe OSA (MS OSA: OAHI>5 events/h). Group differences were found in the percentage of time spent in NREM Stages 1 and 4 (p<0.001) and in the time course of SWA. PS and Mild OSA children had higher SWA in the first NREM period than controls (p<0.05). All SDB groups had higher SWA in the fourth NREM period (p<0.01).
  
  
  CONCLUSIONS
  These results suggest enhanced sleep pressure but impaired restorative sleep function in pre-school children with SDB, providing new insights into the possible mechanism for daytime deficits observed in all severities of SDB.
authors: The Ritchie Centre, Monash Institute of Medical Research, Monash University, Melbourne, Australia. sarah.biggs@monash.edu
authors: Sarah N
authors: SN
authors: Biggs
authors: Lisa M
authors: LM
authors: Walter
authors: Lauren C
authors: LC
authors: Nisbet
authors: Angela R
authors: AR
authors: Jackman
authors: Vicki
authors: V
authors: Anderson
authors: Gillian M
authors: GM
authors: Nixon
authors: Margot J
authors: MJ
authors: Davey
authors: John
authors: J
authors: Trinder
authors: Robert
authors: R
authors: Hoffmann
authors: Roseanne
authors: R
authors: Armitage
authors: Rosemary S C
authors: RS
authors: Horne
mesh_terms: D002540:Cerebral Cortex / Q000254:growth & development / Q000502:physiology; D002675:Child, Preschool; D006970:Disorders of Excessive Somnolence / Q000209:etiology* / Q000503:physiopathology*; D004569:Electroencephalography; D005260:Female; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D008297:Male; D017286:Polysomnography; D011930:Reaction Time / Q000502:physiology; D012890:Sleep / Q000502:physiology*; D012891:Sleep Apnea Syndromes / Q000150:complications* / Q000503:physiopathology*; D012892:Sleep Deprivation / Q000209:etiology / Q000503:physiopathology; D012894:Sleep Stages / Q000502:physiology