The Relationship Between Sleep Disturbance and Apolipoprotein E ε4 in Adults With Mild Cognitive Impairment and Alzheimer’s Disease Dementia: An Integrative Review

Abstract

Background Apolipoprotein E ε4 (APOE ε4) was shown to be a risk factor for mild cognitive impairment (MCI) and Alzheimer’s disease (AD) dementia. When coupled with sleep disturbance, APOE ε4 posed additional risks to cognitive impairment. But the literature on the association between sleep disturbance and the APOE ε4 status of persons who are cognitively impaired has not yet been systematically examined. Objectives To explore and synthesize the relationship between sleep disturbance and APOE ε4 status of adults with MCI and AD. Methods An integrative review was guided by Whittemore and Knafl’s methodology. Systematic searches identified studies with multiple sources published before May 20, 2021. A matrix and narrative synthesis was employed to organize and synthesize the findings. Joanna Briggs Institute (JBI) Critical Appraisal tools (2020) were used to evaluate the quality of the selected studies. Results A total of 7 studies were included. APOE ε4 was associated with poor sleep quality in terms of the deterioration of nighttime total sleep time, 24-hour total sleep time, rapid eye movement, sleep efficiency, sleep latency, and wake after sleep onset in a population with MCI or AD. The interacted and adjusted relationship between sleep disturbance and APOE ε4 on the progression of cognitive decline was inconsistent. Conclusions There is evidence to support an association between sleep disturbance and APOE ε4 in individuals with cognitive impairment, but a further examination of the relationship between sleep parameters and APOE ε4 is warranted, especially as the causal or dose–response relationship remains unclear.

Knowledge Structure and Emerging Trends of Mild Cognitive Impairment with Dyssomnias in Recent 20 Years: A Bibliometric Analysis via CiteSpace and VOSviewer

“…Cluster #11 AD is focused on the keyword “sleep disturbance”. A systematic review has investigated the association between sleep disorders and APOE ε 4 status in individuals with MCI and AD [ 46 ]. The results suggest that APOE ε 4 is associated with poorer sleep quality, including factors such as total sleep time, REM sleep, sleep efficiency, latency, and wakefulness after sleep onset.…”

Respiratory Dysfunction in Alzheimer’s Disease—Consequence or Underlying Cause? Applying Animal Models to the Study of Respiratory Malfunctions

“…The mechanisms underlying the link between APOE-ε4 and AD are far from clear, but the presence of the ε4 allele has been linked to the appearance of amyloid-β (Ab) aggregates, tau hyperphosphorylation, disorganization of mitochondrial networks, and lipid metabolism disruption [130][131][132][133]. APOE-ε4 has also been associated with sleep abnormalities, poor sleep quality, and increased risk of insomnia [134,135]. As for apnea, on the other hand, the data are inconclusive.…”

One-pot, multicomponent oxidative synthesis of 2,4,5-trisubstituted imidazoles from internal alkenes using an I2/DMSO system.

“…132 According to WHO, in 2019, over 50 million people had dementia and AD was the primary cause of dementia as it accounted for 60 -70% dementia cases. 133 AD is a neurodegenerative brain disorder associated with a low level of acetylcholine neurotransmitter either due to reduced synthesis or enzymatic activity of acetylcholinesterase on acetylcholine resulting in memory loss or cognitive impairment. 134 Acetylcholinesterase (AChE) is a hydrolase enzyme that hydrolyzes acetylcholine, which is a major part of central cholinergic pathways in the central nervous system.…”