title: Hippocampal hypertrophy and sleep apnea: a role for the ischemic preconditioning?
abstract: The full impact of multisystem disease such as obstructive sleep apnoea (OSA) on regions of the central nervous system is debated, as the subsequent neurocognitive sequelae are unclear. Several preclinical studies suggest that its purported major culprits, intermittent hypoxia and sleep fragmentation, can differentially affect adult hippocampal neurogenesis. Although the prospective biphasic nature of chronic intermittent hypoxia in animal models of OSA has been acknowledged, so far the evidence for increased 'compensatory' neurogenesis in humans is uncertain. In a cross-sectional study of 32 patients with mixed severity OSA and 32 non-apnoeic matched controls inferential analysis showed bilateral enlargement of hippocampi in the OSA group. Conversely, a trend for smaller thalami in the OSA group was noted. Furthermore, aberrant connectivity between the hippocampus and the cerebellum in the OSA group was also suggested by the correlation analysis. The role for the ischemia/hypoxia preconditioning in the neuropathology of OSA is herein indicated, with possible further reaching clinical implications.
authors.affiliation: Department of Neuroimaging, Institute of Psychiatry, King's College, London, United Kingdom ; Danish Epilepsy Centre, Dianalund, Denmark.
authors.forename: Ivana
authors.initials: I
authors.lastname: Rosenzweig
authors.affiliation: Department of Neuroimaging, Institute of Psychiatry, King's College, London, United Kingdom.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Kempton
authors.affiliation: Department of Neuroimaging, Institute of Psychiatry, King's College, London, United Kingdom.
authors.forename: William R
authors.initials: WR
authors.lastname: Crum
authors.affiliation: Academic Unit of Sleep and Breathing, National Heart and Lung Institute, Imperial College London, London, United Kingdom ; NIHR Respiratory Disease Biomedical Research Unit at the Royal Brompton and Harefield NHS Foundation Trust and Imperial College London, London, United Kingdom.
authors.forename: Martin
authors.initials: M
authors.lastname: Glasser
authors.affiliation: Department for Environmental and Occupational Health, University of Zagreb, School of Medicine, Andrija Štampar School of Public Health, Zagreb, Croatia.
authors.forename: Milan
authors.initials: M
authors.lastname: Milosevic
authors.affiliation: Danish Epilepsy Centre, Dianalund, Denmark ; Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Sandor
authors.initials: S
authors.lastname: Beniczky
authors.affiliation: Manchester Medical School, University of Manchester, Manchester, United Kingdom.
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Corfield
authors.affiliation: Department of Neuroimaging, Institute of Psychiatry, King's College, London, United Kingdom.
authors.forename: Steven C
authors.initials: SC
authors.lastname: Williams
authors.affiliation: Academic Unit of Sleep and Breathing, National Heart and Lung Institute, Imperial College London, London, United Kingdom ; NIHR Respiratory Disease Biomedical Research Unit at the Royal Brompton and Harefield NHS Foundation Trust and Imperial College London, London, United Kingdom.
authors.forename: Mary J
authors.initials: MJ
authors.lastname: Morrell
mesh_terms: D000328:Adult; D005260:Female; D006624:Hippocampus / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D006984:Hypertrophy; D019194:Ischemic Preconditioning; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012891:Sleep Apnea Syndromes / Q000000981:diagnostic imaging* / Q000503:physiopathology