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Sleep, Cognition and Dementia


The older patient population is growing rapidly around the world and in the USA. Almost half of seniors over age 65 who live at home are dissatisfied with their sleep, and nearly two-thirds of those residing in nursing home facilities suffer from sleep disorders. Chronic and pervasive sleep complaints and disturbances are frequently associated with excessive daytime sleepiness and may result in impaired cognition, diminished intellect, poor memory, confusion, and psychomotor retardation all of which may be misinterpreted as dementia. The key sleep disorders impacting patients with dementia include insomnia, hypersomnolence, circadian rhythm misalignment, sleep disordered breathing, motor disturbances of sleep such as periodic leg movement disorder of sleep and restless leg syndrome, and parasomnias, mostly in the form of rapid eye movement (REM) sleep behavior disorder (RBD). RBD is a pre-clinical marker for a class of neurodegenerative diseases, the “synucleinopathies”, and requires formal polysomnographic evaluation. Untreated sleep disorders may exacerbate cognitive and behavioral symptoms in patients with dementia and are a source of considerable stress for bed partners and family members. When left untreated, sleep disturbances may also increase the risk of injury at night, compromise health-related quality of life, and precipitate and accelerate social and economic burdens for caregivers.

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This material is the result of work supported with the resources and use of facilities at the UCLA Department of Neurology in Los Angeles, California, USA.

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Correspondence to Alon Y. Avidan.

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Verna R. Porter and William G. Buxton declare that they have no conflict of interest.

Alon Y. Avidan is a consultant for Vanda, Merck, is on the speaker’s bureau for Merck and Xenoport and received stipends as an author and lecturer on behalf of the Elsevier, LWW, Best Doctors, AAN, AASM, ACCP, and CHEST.

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Porter, V.R., Buxton, W.G. & Avidan, A.Y. Sleep, Cognition and Dementia. Curr Psychiatry Rep 17, 97 (2015).

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  • Sleep
  • Sleep disorders
  • Dementia
  • Neurodegenerative disease
  • Sun-downing
  • Aging
  • REM sleep behavior disorder
  • Alpha synucleinopathies
  • Alzheimer’s dementia