Are Sleep Disorders Associated With Cognitive Decline?

Check out this answer from Consensus:

The evidence strongly supports an association between sleep disorders and cognitive decline. Specific conditions like REM Sleep Behavior Disorder, Excessive Daytime Sleepiness, and Obstructive Sleep Apnea are particularly implicated. Poor sleep quality and abnormal sleep duration also contribute to cognitive impairment. These findings highlight the importance of sleep management in potentially mitigating the risk of cognitive decline and dementia.

Sleep disorders are increasingly recognized as potential risk factors for cognitive decline and dementia. This synthesis examines the association between various sleep disturbances and cognitive impairment, drawing on findings from multiple research studies.

Key Insights

• General Association Between Sleep Disorders and Cognitive Decline:
  • Multiple studies confirm that sleep disorders, including insomnia, sleep fragmentation, and excessive daytime sleepiness, are linked to a higher risk of cognitive decline and dementia1 5 6 9.
• Specific Sleep Disorders and Cognitive Impairment:
  • REM Sleep Behavior Disorder (RBD) and Excessive Daytime Sleepiness (EDS) are particularly associated with deficits in global cognitive functioning, memory, executive functions, and attention/working memory2 7 10.
  • Obstructive Sleep Apnea (OSA) is linked to mild cognitive impairment (MCI) and Alzheimer’s disease (AD), with CPAP treatment potentially improving cognitive outcomes in OSA patients3 9.
• Sleep Quality and Aging:
  • Poor sleep quality, including reduced REM sleep, sleep efficiency, and increased sleep latency, is associated with cognitive impairment in older adults, including those with MCI and AD4 8.
• Daytime Sleepiness and Cognitive Decline:
  • Excessive daytime sleepiness is independently associated with an increased risk of dementia and cognitive decline, suggesting it may serve as an early marker for neurodegenerative diseases7 10.
• Sleep Duration and Cognitive Health:
  • A U-shaped relationship exists between sleep duration and cognitive health, with both short and long sleep durations linked to higher risks of cognitive disorders1.

Are sleep disorders associated with cognitive decline?

Michelle Olaithe has answered Near Certain

An expert from University of Western Australia in Psychology, Sleep Research

Sleep disorder is an important, and potentially modifiable risk factor for Alzhemier’s disease and other dementias [1] [2] [3]. Obstructive Sleep Apnoea (OSA) is a highly prevalent sleep and breathing disorder involving blood gas disruptions and disturbed sleep. Despite its ubiquity, OSA is likely underdiagnosed [4] and certainly under-treated [5]. This is problematic, as the longer OSA goes untreated the greater the risk of Mild Cognitive Impairment (MCI) [1], dementia [2], and early onset of Alzheimer’s disease [3]. Furthermore, there is delayed onset of MCI and dementia with successful treatment of OSA [1] [2] [3]. 

1.           Yaffe, K., A.M. Laffan, and S.L. Harrison, Sleep-disordered breathing, hypoxia, and risk of mild cognitive impairment and dementia in older women. JAMA, 2011. 306: p. 613-19.
2.           Daulatzai, M.A., Evidence of neurodegeneration in obstructive sleep apnea: Relationship between obstructive sleep apnea and cognitive dysfunction in the elderly. J Neurosci Res, 2015. 93(12): p. 1778-94.
3.           Osorio, R.S., et al., Sleep-disordered breathing advances cognitive decline in the elderly. Neurology, 2015. 84(19): p. 1964-71.
4.           Simpson, L., et al., High prevalence of undiagnosed obstructive sleep apnoea in the general population and methods for screening for representative controls. Sleep and Breathing, 2012. 17(3): p. 967-73.
5.           Gibson, G.J., Obstructive sleep apnoea syndrome: underestimated and undertreated. British Medical Bulletin, 2004. 72(1): p. 49-64.