title: Regional Cerebral Blood Flow during Wakeful Rest in Older Subjects with Mild to Severe Obstructive Sleep Apnea.
abstract: OBJECTIVE
  To evaluate changes in regional cerebral blood flow (rCBF) during wakeful rest in older subjects with mild to severe obstructive sleep apnea (OSA) and healthy controls, and to identify markers of OSA severity that predict altered rCBF.
  
  
  METHODS
  High-resolution (99m)Tc-HMPAO SPECT imaging during wakeful rest.
  
  
  METHODS
  Research sleep laboratory affiliated with a University hospital.
  
  
  METHODS
  Fifty untreated OSA patients aged between 55 and 85 years, divided into mild, moderate, and severe OSA, and 20 age-matched healthy controls.
  
  
  METHODS
  N/A.
  
  
  METHODS
  Using statistical parametric mapping, rCBF was compared between groups and correlated with clinical, respiratory, and sleep variables.
  
  
  RESULTS
  Whereas no rCBF change was observed in mild and moderate groups, participants with severe OSA had reduced rCBF compared to controls in the left parietal lobules, left precentral gyrus, bilateral postcentral gyri, and right precuneus. Reduced rCBF in these regions and in areas of the bilateral frontal and left temporal cortex was associated with more hypopneas, snoring, hypoxemia, and sleepiness. Higher apnea, microarousal, and body mass indexes were correlated to increased rCBF in the basal ganglia, insula, and limbic system.
  
  
  CONCLUSIONS
  While older individuals with severe obstructive sleep apnea (OSA) had hypoperfusion in the sensorimotor and parietal areas, respiratory variables and subjective sleepiness were correlated with extended regions of hypoperfusion in the lateral cortex. Interestingly, OSA severity, sleep fragmentation, and obesity correlated with increased perfusion in subcortical and medial cortical regions. Anomalies with such a distribution could result in cognitive deficits and reflect impaired vascular regulation, altered neuronal integrity, and/or undergoing neurodegenerative processes.
authors.affiliation: Center for Advanced Research in Sleep Medicine (CARSM), Hôpital du Sacré-Coeur de Montréal, Montreal, Quebec, Canada.|Université de Montréal, Department of Psychiatry, Montreal, Quebec, Canada.
authors.forename: Andrée-Ann
authors.initials: AA
authors.lastname: Baril
authors.affiliation: Center for Advanced Research in Sleep Medicine (CARSM), Hôpital du Sacré-Coeur de Montréal, Montreal, Quebec, Canada.|Université du Québec à Montréal, Department of Psychology, Montreal, Quebec, Canada.
authors.forename: Katia
authors.initials: K
authors.lastname: Gagnon
authors.affiliation: Center for Advanced Research in Sleep Medicine (CARSM), Hôpital du Sacré-Coeur de Montréal, Montreal, Quebec, Canada.|Université de Montréal, Department of Psychology, Montreal, Quebec, Canada.
authors.forename: Caroline
authors.initials: C
authors.lastname: Arbour
authors.affiliation: McGill University, McConnell Brain Imaging Centre, Montreal, Quebec, Canada.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Soucy
authors.affiliation: Center for Advanced Research in Sleep Medicine (CARSM), Hôpital du Sacré-Coeur de Montréal, Montreal, Quebec, Canada.|Université de Montréal, Department of Psychiatry, Montreal, Quebec, Canada.
authors.forename: Jacques
authors.initials: J
authors.lastname: Montplaisir
authors.affiliation: Center for Advanced Research in Sleep Medicine (CARSM), Hôpital du Sacré-Coeur de Montréal, Montreal, Quebec, Canada.|Université du Québec à Montréal, Department of Psychology, Montreal, Quebec, Canada.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Gagnon
authors.affiliation: Center for Advanced Research in Sleep Medicine (CARSM), Hôpital du Sacré-Coeur de Montréal, Montreal, Quebec, Canada.|Université de Montréal, Department of Psychology, Montreal, Quebec, Canada.
authors.forename: Nadia
authors.initials: N
authors.lastname: Gosselin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002540:Cerebral Cortex / Q000098:blood supply / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D003072:Cognition Disorders / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012146:Rest / Q000502:physiology*; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology*; D012892:Sleep Deprivation / Q000503:physiopathology; D012894:Sleep Stages / Q000502:physiology; D015899:Tomography, Emission-Computed, Single-Photon; D014851:Wakefulness / Q000502:physiology*
keywords: SPECT; aging; cerebral perfusion; neuroimaging; obstructive sleep apnea; regional cerebral blood flow; snoring