ArticleBrain sciences2017
In Search of Sleep Biomarkers of Alzheimer's Disease: K-Complexes Do Not Discriminate between Patients with Mild Cognitive Impairment and Healthy Controls.
Article in Brain sciences, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 25 papers, 2 of them syntheses that pooled it.
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Who cites it
25 citing papers in PubMed, 2 syntheses or guidelines pooled it, 50 citations in OpenAlex.
- Characteristics of macroscopic sleep structure in patients with mild cognitive impairment: a systematic review.Frontiers in psychiatry · 2023Pooled it
- Characteristics of Sleep Structure Assessed by Objective Measurements in Patients With Amnestic Mild Cognitive Impairment: A Meta-Analysis.Frontiers in neurology · 2020Pooled it
- A New Electrophysiological Approach to Sleep Microstructure: The Gülhane Classification of K-Complex Subtypes in Narcolepsy Type 1 and Type 2.Life (Basel, Switzerland) · 2026Article
- Transformer-Based Multi-Channel K-Complex Detection Algorithm Tailored for Elderly Patients With Amnestic Mild Cognitive Impairment.Journal of sleep research · 2026Article
- Disruption of sleep macro- and microstructure in Alzheimer's disease: overlaps between neuropsychology, neurophysiology, and neuroimaging.GeroScience · 2025Article
- Slow wave synchrony during NREM sleep tracks cognitive impairment in prodromal Alzheimer's disease.Alzheimer's & dementia : the journal of the Alzheimer's Association · 2025Article
- Sleep architecture in Alzheimer's disease continuum: The deep sleep question.Open life sciences · 2025Article
- Linking activity dyshomeostasis and sleep disturbances in Alzheimer disease.Nature reviews. Neuroscience · 2024Review
- An Exploratory Study of Sleep-Wake Differences of Autonomic Activity in Patients with Mild Cognitive Impairment: The Role of Melatonin as a Modulating Factor.Clinical interventions in aging · 2023Article
- How non-rapid eye movement sleep and Alzheimer pathology are linked.World journal of psychiatry · 2021Review
- Sleep disorders in Alzheimer's disease: the predictive roles and potential mechanisms.Neural regeneration research · 2021Review
- The Regional EEG Pattern of the Sleep Onset Process in Older Adults.Brain sciences · 2021Article
- EEG alterations during wake and sleep in mild cognitive impairment and Alzheimer's disease.iScience · 2021Article
- Sleep-Based Interventions in Alzheimer's Disease: Promising Approaches from Prevention to Treatment along the Disease Trajectory.Pharmaceuticals (Basel, Switzerland) · 2021Review
- Sleep in the Aging Brain.Brain sciences · 2021Article
- Sleep, Mild Cognitive Impairment, and Interventions for Sleep Improvement: An Integrative Review.Western journal of nursing research · 2021Article
- Association between sleep structure and amnesic mild cognitive impairment in patients with insomnia disorder: a case-control study.Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine · 2021Article
- Insights from human sleep research on neural mechanisms of Alzheimer's disease.Neural regeneration research · 2020Article
- Sleep spindles, K-complexes, limb movements and sleep stage proportions may be biomarkers for amnestic mild cognitive impairment and Alzheimer's disease.Sleep & breathing = Schlaf & Atmung · 2020Article
- The Influence of Sleep Quality, Vigilance, and Sleepiness on Driving-Related Cognitive Abilities: A Comparison between Young and Older Adults.Brain sciences · 2020Article
Corrections and comments
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Authors and funding
13 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The K-complex (KC) is one of the hallmarks of Non-Rapid Eye Movement (NREM) sleep. Recent observations point to a drastic decrease of spontaneous KCs in Alzheimer's disease (AD). However, no study has investigated when, in the development of AD, this phenomenon starts. The assessment of KC density in mild cognitive impairment (MCI), a clinical condition considered a possible transitional stage between normal cognitive function and probable AD, is still lacking. The aim of the present study was to compare KC density in AD/MCI patients and healthy controls (HCs), also assessing the relationship between KC density and cognitive decline. Twenty amnesic MCI patients underwent a polysomnographic recording of a nocturnal sleep. Their data were compared to those of previously recorded 20 HCs and 20 AD patients. KCs during stage 2 NREM sleep were visually identified and KC densities of the three groups were compared. AD patients showed a significant KC density decrease compared with MCI patients and HCs, while no differences were observed between MCI patients and HCs. KC density was positively correlated with Mini-Mental State Examination (MMSE) scores. Our results point to the existence of an alteration of KC density only in a full-blown phase of AD, which was not observable in the early stage of the pathology (MCI), but linked with cognitive deterioration.
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