Changes in Neurocognitive Architecture in Patients with Obstructive Sleep Apnea Treated with Continuous Positive Airway Pressure.
BACKGROUND
Obstructive sleep apnea (OSA) is a chronic, multisystem disorder that has a bidirectional relationship with several major neurological disorders, including Alzheimer's dementia. Treatment with Continuous Positive Airway Pressure (CPAP) offers some protection from the effects of OSA, although it is still unclear which populations should be targeted, for how long, and what the effects of treatment are on different organ systems. We investigated whether cognitive improvements can be achieved as early as one month into CPAP treatment in patients with OSA.


METHODS
55 patients (mean (SD) age: 47.6 (11.1) years) with newly diagnosed moderate-severe OSA (Oxygen Desaturation Index: 36.6 (25.2) events/hour; Epworth sleepiness score (ESS): 12.8 (4.9)) and 35 matched healthy volunteers were studied. All participants underwent neurocognitive testing, neuroimaging and polysomnography. Patients were randomized into parallel groups: CPAP with best supportive care (BSC), or BSC alone for one month, after which they were re-tested.


RESULTS
One month of CPAP with BSC resulted in a hypertrophic trend in the right thalamus [mean difference (%): 4.04, 95% CI: 1.47 to 6.61], which was absent in the BSC group [-2.29, 95% CI: -4.34 to -0.24]. Significant improvement was also recorded in ESS, in the CPAP plus BSC group, following treatment [mean difference (%): -27.97, 95% CI: -36.75 to -19.19 vs 2.46, 95% CI: -5.23 to 10.15; P=0.012], correlated to neuroplastic changes in brainstem (r=-0.37; P=0.05), and improvements in delayed logical memory scores [57.20, 95% CI: 42.94 to 71.46 vs 23.41, 95% CI: 17.17 to 29.65; P=0.037].


CONCLUSIONS
One month of CPAP treatment can lead to adaptive alterations in the neurocognitive architecture that underlies the reduced sleepiness, and improved verbal episodic memory in patients with OSA. We propose that partial neural recovery occurs during short periods of treatment with CPAP.
Sleep and Brain Plasticity Centre, Department of Neuroimaging, IoPPN, King's College and Imperial College London, UK; Danish Epilepsy Centre, Dianalund, Denmark; Sleep Disorders Centre, Guy's and St Thomas' NHS Foundation Trust, UK. Electronic address: ivana.1.rosenzweig@kcl.ac.uk.
Ivana
I
Rosenzweig
Academic Unit of Sleep and Breathing, National Heart and Lung Institute, Imperial College London, UK; NIHR Respiratory Disease Biomedical Research Unit at the Royal Brompton and Harefield NHS Foundation Trust, Sydney Street, London SW3 6NP, UK.
Martin
M
Glasser
Sleep and Brain Plasticity Centre, Department of Neuroimaging, IoPPN, King's College and Imperial College London, UK; IoPPN, King's College London, UK.
William R
WR
Crum
Sleep and Brain Plasticity Centre, Department of Neuroimaging, IoPPN, King's College and Imperial College London, UK; IoPPN, King's College London, UK.
Matthew J
MJ
Kempton
Department for Environmental and Occupational Health, University of Zagreb, School of Medicine, Andrija Štampar School of Public Health, Zagreb, Croatia.
Milan
M
Milosevic
Academic Unit of Sleep and Breathing, National Heart and Lung Institute, Imperial College London, UK; NIHR Respiratory Disease Biomedical Research Unit at the Royal Brompton and Harefield NHS Foundation Trust, Sydney Street, London SW3 6NP, UK.
Alison
A
McMillan
Sleep and Brain Plasticity Centre, Department of Neuroimaging, IoPPN, King's College and Imperial College London, UK; Sleep Disorders Centre, Guy's and St Thomas' NHS Foundation Trust, UK; Department of Basic and Clinical Neuroscience, IoPPN, King's College London, UK.
Guy D
GD
Leschziner
Department of Psychology, IoPPN, King's College London, UK.
Veena
V
Kumari
Department of Basic and Clinical Neuroscience, IoPPN, King's College London, UK; IoPPN, King's College London, UK.
Peter
P
Goadsby
Academic Unit of Sleep and Breathing, National Heart and Lung Institute, Imperial College London, UK; NIHR Respiratory Disease Biomedical Research Unit at the Royal Brompton and Harefield NHS Foundation Trust, Sydney Street, London SW3 6NP, UK.
Anita K
AK
Simonds
Sleep and Brain Plasticity Centre, Department of Neuroimaging, IoPPN, King's College and Imperial College London, UK; IoPPN, King's College London, UK.
Steve C R
SC
Williams
Sleep and Brain Plasticity Centre, Department of Neuroimaging, IoPPN, King's College and Imperial College London, UK; Academic Unit of Sleep and Breathing, National Heart and Lung Institute, Imperial College London, UK; NIHR Respiratory Disease Biomedical Research Unit at the Royal Brompton and Harefield NHS Foundation Trust, Sydney Street, London SW3 6NP, UK.
Mary J
MJ
Morrell
D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging*; D003071:Cognition / Q000502:physiology*; D045422:Continuous Positive Airway Pressure / Q000379:methods*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D017286:Polysomnography; D011788:Quality of Life; D011897:Random Allocation; D020181:Sleep Apnea, Obstructive / Q000473:pathology / Q000628:therapy*; D016896:Treatment Outcome
Cognition; Continuous Positive Airway Pressure; Neuroimaging; Obstructive sleep apnea