Sleep characteristics and cognitive impairment in the general population: The HypnoLaus study.

TitreSleep characteristics and cognitive impairment in the general population: The HypnoLaus study.
Publication TypeJournal Article
Year of Publication2017
AuthorsHaba-Rubio, J, Marti-Soler, H, Tobback, N, Andries, D, Marques-Vidal, P, Waeber, G, Vollenweider, P, von Gunten, A, Preisig, M, Castelao, E, Tafti, M, Heinzer, R, Popp, J
Date Published2017 Jan 31
Mots-clésAged, Cognitive Dysfunction, Follow-Up Studies, Humans, Mental Status Schedule, Multivariate Analysis, Neuropsychological Tests, Polysomnography, Severity of Illness Index, Sleep, Sleep Wake Disorders, Surveys and Questionnaires, Switzerland

OBJECTIVE: To assess the association between sleep structure and cognitive impairment in the general population.

METHODS: Data stemmed from 580 participants aged >65 years of the population-based CoLaus/PsyCoLaus study (Lausanne, Switzerland) who underwent complete sleep evaluation (HypnoLaus). Evaluations included demographic characteristics, personal and treatment history, sleep complaints and habits (using validated questionnaires), and a complete polysomnography at home. Cognitive function was evaluated using a comprehensive neuropsychological test battery and a questionnaire on the participant's everyday activities. Participants with cognitive impairment (global Clinical Dementia Rating [CDR] scale score > 0) were compared with participants with no cognitive impairment (global CDR score = 0).

RESULTS: The 291 participants with a CDR score > 0 (72.5 ± 4.6 years), compared to the 289 controls with CDR = 0 (72.1 ± 4.6 years), had significantly more light (stage N1) and less deep (stage N3) and REM sleep, as well as lower sleep efficiency, higher intrasleep wake, and higher sleepiness scores (all p < 0.05). Sleep-disordered breathing was more severe in participants with cognitive impairment with an apnea/hypopnea index (AHI) of 18.0 (7.8-35.5)/h (p50 [p25-p75]) (vs 12.9 [7.2-24.5]/h, p < 0.001), and higher oxygen desaturation index (ODI). In the multivariate analysis after adjustments for confounding variables, the AHI and the ODI ≥4% and ≥6% were independently associated with cognitive impairment.

CONCLUSIONS: Participants aged >65 years with cognitive impairment have higher sleepiness scores and a more disrupted sleep. This seems to be related to the occurrence of sleep-disordered breathing and the associated intermittent hypoxia.

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First publication date (online)


Alternate JournalNeurology
Citation Key / SERVAL IDBIB_32B36047428A
Peer reviewRefereed
PubMed ID28039311

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