title: A pilot study of sleep, cognition, and respiration under 4 weeks of intermittent nocturnal hypoxia in adult humans.
abstract: OBJECTIVE
  A pilot study to examine the effects of intermittent nocturnal hypoxia on sleep, respiration and cognition in healthy adult humans.
  
  
  METHODS
  Participants were eight healthy, non-smoking subjects (four male, four female), mean age of 26.4+/-5.2 years, and BMI 22.3+/-2.6 kg/m(2), exposed to 9h of intermittent hypoxia between the hours of 10 P.M. and 7 A.M. for 28 consecutive nights. At a simulated altitude of 13,000 feet (FIO(2) 0.13), intermittent hypoxia was achieved by administering nasal nitrogen, alternating with brief (approximately 5s) boluses of nasal oxygen. Pre- and post-exposure assessments included polysomnography, attention (20-min Psychomotor Vigilance Test), working memory (10-min verbal 2 and 3-back), Multiple Sleep Latency Test, and the Rey Auditory Verbal Learning Test. Obstructive and non-obstructive respiratory events were scored.
  
  
  RESULTS
  Overall sleep quality showed worsening trends but no statistically significant change following exposure. There was no difference after hypoxia in sleepiness, encoding, attention or working memory. Hyperoxic central apneas and post-hyperoxic respiratory instability were noted as special features of disturbed respiratory control induced by intermittent nocturnal hypoxia.
  
  
  CONCLUSIONS
  In this model, exposure to nocturnal intermittent hypoxia for 4 weeks caused no significant deficits in subjective or objective alertness, vigilance, or working memory.
authors.affiliation: Beth Israel Deaconess Medical Center & Harvard Medical School, KB 023, Pulmonary Office, 330 Brookline Avenue, Boston, MA 02215, USA.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Weiss
authors.forename: Renaud
authors.initials: R
authors.lastname: Tamisier
authors.forename: Judith
authors.initials: J
authors.lastname: Boucher
authors.forename: Mekkin
authors.initials: M
authors.lastname: Lynch
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Gilmartin
authors.forename: J Woodrow
authors.initials: JW
authors.lastname: Weiss
authors.forename: Robert Joseph
authors.initials: RJ
authors.lastname: Thomas
mesh_terms: D000328:Adult; D001143:Arousal / Q000502:physiology; D015992:Body Mass Index; D002680:Chin / Q000294:innervation; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology*; D004576:Electromyography; D004585:Electrooculography; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000453:epidemiology* / Q000503:physiopathology*; D008297:Male; D018482:Muscle, Skeletal / Q000294:innervation; D009483:Neuropsychological Tests; D010865:Pilot Projects; D017286:Polysomnography; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis / Q000453:epidemiology*; D012894:Sleep Stages / Q000502:physiology; D014851:Wakefulness