Alzheimer's disease phenotypes show different sleep architecture
Neus Falgàs1,2,3, Christine M Walsh1, Leslie Yack1,4
1Department of Neurology, Memory & Aging Center, Weill Institute for Neurosciences, University of California, San Francisco, California, USA.
Alzheimer'S & Dementia : the Journal of the Alzheimer'S Association
|February 7, 2023
Summary
Alzheimer's disease variants disrupt sleep differently. Typical Alzheimer's disease impairs deep sleep (N3), while atypical forms affect REM sleep more, suggesting distinct brain vulnerabilities and treatment needs.
Area of Science:
- Neuroscience
- Sleep Medicine
- Neurology
Background:
- Sleep-wake disturbances are common in Alzheimer's disease (AD).
- Atypical (non-amnestic) AD syndromes exhibit unique cortical vulnerability patterns.
- This study investigates if atypical AD also shows differential subcortical vulnerability impacting sleep.
Purpose of the Study:
- To compare sleep architecture in amnestic AD, atypical AD, and control groups.
- To test the hypothesis of differential subcortical vulnerability in AD variants.
- To identify distinct sleep dysfunction patterns associated with AD phenotypes.
Main Methods:
- Overnight electroencephalography (EEG) monitoring was conducted on 48 participants (15 amnestic AD, 19 atypical AD, 14 controls).
- AD diagnosis was confirmed by neuropathology or biomarkers.
- Sleep architecture was analyzed using visual scoring and spectral power analysis.
Main Results:
- Alzheimer's disease cases exhibited increased sleep fragmentation and N1 sleep compared to controls.
- Typical AD showed more severe N3 sleep (slow wave sleep) impairment than atypical AD.
- Atypical AD demonstrated relatively more pronounced rapid eye movement (REM) sleep deficits.
Conclusions:
- Amnestic and atypical AD variants differentially affect slow wave sleep and REM sleep, respectively.
- These findings support the hypothesis of selective vulnerability in subcortical nuclei across AD variants.
- Tailored symptomatic treatments for sleep disturbances may be necessary for different clinical AD phenotypes.
Related Concept Videos
01:26Alzheimer's Disease: Overview
594
Alzheimer's Disease (AD) is a continually advancing neurodegenerative disorder, distinguished by escalating memory loss, cognitive dysfunction, and dementia. The disease unfolds in three stages: preclinical, mild cognitive impairment (MCI), and dementia. Its onset is insidious, and the progression gradual, with the cause not well explained by other disorders.
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ...
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ...
594
01:24Sleep-Wake Cycles
1.5K
Sleep is an essential physiological process vital to maintaining overall well-being. The reticular activating system (RAS), a network of neurons in the brainstem, regulates wakefulness and sleep. While it may seem passive, sleep consists of distinct cycles, each with its unique characteristics and functions. Two key sleep phases are non-rapid eye movement (NREM) and rapid eye movement (REM).
NREM Sleep
NREM sleep comprises four progressive stages that seamlessly merge:
NREM Sleep
NREM sleep comprises four progressive stages that seamlessly merge:
1.5K
01:15REM Sleep Behavior Disorder
319
REM Sleep Behavior Disorder (RBD) is a sleep disorder characterized by the absence of muscle paralysis that normally occurs during the REM phase of sleep. This absence allows individuals to physically act out their dreams, which are often vivid and disturbing. Common behaviors exhibited during episodes include kicking, punching, and yelling. These actions can be dangerous, potentially leading to injuries for the person with RBD or their bed partner.
RBD is significantly associated with...
RBD is significantly associated with...
319
01:07Narcolepsy
174
Narcolepsy is a chronic sleep disorder characterized by pervasive, uncontrolled sleepiness and other sleep disturbances. One of its hallmark symptoms is an abrupt transition to REM sleep upon falling asleep, which causes symptoms typically associated with this phase to occur unexpectedly during wakefulness. These include the following symptoms, which typically last from a minute or two to half an hour.
174
01:22Stages of Sleep
413
Sleep progresses through distinct stages, each characterized by specific brain wave patterns and physiological responses ranging from wakefulness to stages of non-rapid eye movement, known as non-REM, to rapid eye movement, referred to as REM. Understanding these stages helps in recognizing how sleep supports various bodily and cognitive functions.
Before sleep begins, in wakefulness, the brain exhibits primarily beta waves, which are high in frequency and low in amplitude, indicating alertness...
Before sleep begins, in wakefulness, the brain exhibits primarily beta waves, which are high in frequency and low in amplitude, indicating alertness...
413
01:24Substance Use Disorders Affecting Sleep
205
Substance use disorders involve a pattern of using drugs more extensively than intended and continuing use despite harmful consequences. This includes legal substances like alcohol and nicotine, as well as illegal drugs. These disorders often involve both physical and psychological dependence, reflecting compulsive use of substances that significantly alter thoughts, feelings, and behaviors, contributing to a major public health issue.
Understanding the concepts of physical dependence,...
Understanding the concepts of physical dependence,...
205