title: Working memory impairment and its associated sleep-related respiratory parameters in children with obstructive sleep apnea.
abstract: OBJECTIVE
  Working memory deficits in children with obstructive sleep apnea (OSA) have been reported in previous studies, but the results were inconclusive. This study tried to address this issue by delineating working memory functions into executive processes and storage/maintenance components based on Baddeley's working memory model.
  
  
  METHODS
  Working memory and basic attention tasks were administered on 23 OSA children aged 8-12 years and 22 age-, education-, and general cognitive functioning-matched controls. Data on overnight polysomnographic sleep study and working memory functions were compared between the two groups. Associations between respiratory-related parameters and cognitive performance were explored in the OSA group.
  
  
  RESULTS
  Compared with controls, children with OSA had poorer performance on both tasks of basic storage and central executive components in the verbal domain of working memory, above and beyond basic attention and processing speed impairments; such differences were not significant in the visuo-spatial domain. Moreover, correlational analyses and hierarchical regression analyses further suggested that obstructive apnea-hypopnea index (OAHI) and oxygen saturation (SpO2) nadir were associated with verbal working memory performance, highlighting the potential pathophysiological mechanisms of OSA-induced cognitive deficits.
  
  
  CONCLUSIONS
  Verbal working memory impairments associated with OSA may compromise children's learning potentials and neurocognitive development. Early identification of OSA and assessment of the associated neurocognitive deficits are of paramount importance. Reversibility of cognitive deficits after treatment would be a critical outcome indicator.
authors: Sleep Laboratory, University of Hong Kong, Hong Kong; Department of Psychology, University of Hong Kong, Hong Kong; Department of Psychiatry, University of Hong Kong, Hong Kong. Electronic address: eyylau@hku.hk.
authors: Esther Yuet Ying
authors: EY
authors: Lau
authors: Sleep Laboratory, University of Hong Kong, Hong Kong.
authors: Elizabeth W M
authors: EW
authors: Choi
authors: Sleep Laboratory, University of Hong Kong, Hong Kong.
authors: Esther S K
authors: ES
authors: Lai
authors: Sleep Laboratory, University of Hong Kong, Hong Kong; Department of Psychology, University of Hong Kong, Hong Kong.
authors: Kristy N T
authors: KN
authors: Lau
authors: Department of Pediatrics, Prince of Wales Hospital, Hong Kong.
authors: C T
authors: CT
authors: Au
authors: School of Biomedical Sciences, Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong.
authors: W H
authors: WH
authors: Yung
authors: Department of Pediatrics, Prince of Wales Hospital, Hong Kong.
authors: Albert M
authors: AM
authors: Li
mesh_terms: D016022:Case-Control Studies; D002648:Child; D002681:China; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*; D008570:Memory, Short-Term / Q000502:physiology*; D009483:Neuropsychological Tests; D017286:Polysomnography; D012129:Respiratory Function Tests; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000503:physiopathology / Q000523:psychology*
keywords: Hypoxemia; Neurocognitive; OSA; Pediatric; Sleep; Working memory