Summary Sleep disturbances and cognitive impairment are common in older adults. Mounting evidence points to a potential connection between sleep and cognitive function. Findings from observational studies support a role for sleep disturbances (particularly for sleep duration, sleep fragmentation, and sleep-disordered breathing) in the development of cognitive impairment. Less consistent evidence exists for associations of insomnia and circadian rhythm dysfunction with cognition. These findings suggest that the sleep–wake cycle plays a crucial part in brain ageing, pointing to a potential avenue for improvement of cognitive outcomes in people at risk of cognitive decline and dementia. Several biological mechanisms might underlie the association between sleep and cognition, but these pathways are not completely understood. Future studies that aim to clarify the association between sleep and cognition might help to identify people at risk of cognitive disorders and to facilitate the development of novel therapies to treat and potentially prevent both sleep disturbances and cognitive impairment.

https://www.thelancet.com/pdfs/journals/laneur/PIIS1474-4422(14)70172-3.pdf

Connections between sleep and cognition in older adults

Importance Sleep and circadian problems are very common in Alzheimer disease (AD). Recent animal studies suggest a bidirectional relationship between sleep and β-amyloid (Aβ), a key molecule involved in AD pathogenesis. Objective To test whether Aβ deposition in preclinical AD, prior to the appearance of cognitive impairment, is associated with changes in quality or quantity of sleep. Design Cross-sectional study conducted from October 2010 to June 2012. Setting General community volunteers at the Washington University Knight Alzheimer's Disease Research Center. Participants Cognitively normal individuals (n = 145) 45 years and older were recruited from longitudinal studies of memory and aging at the Washington University Knight Alzheimer's Disease Research Center. Valid actigraphy data were recorded in 142. The majority (124 of 142) were recruited from the Adult Children Study, in which all were aged 45 to 75 years at baseline and 50% have a parental history of late-onset AD. The rest were recruited from a community volunteer cohort in which all were older than 60 years and healthy at baseline. Main Outcome Measures Sleep was objectively measured using actigraphy for 2 weeks. Sleep efficiency, which is the percentage of time in bed spent asleep, was the primary measure of sleep quality. Total sleep time was the primary measure of sleep quantity. Cerebrospinal fluid Aβ42 levels were used to determine whether amyloid deposition was present or absent. Concurrent sleep diaries provided nap information. Results Amyloid deposition, as assessed by Aβ42 levels, was present in 32 participants (22.5%). This group had worse sleep quality, as measured by sleep efficiency (80.4% vs 83.7%), compared with those without amyloid deposition, after correction for age, sex, and APOE ϵ4 allele carrier status (P = .04). In contrast, quantity of sleep was not significantly different between groups, as measured by total sleep time. Frequent napping, 3 or more days per week, was associated with amyloid deposition (31.2% vs 14.7%; P = .03). Conclusions and Relevance Amyloid deposition in the preclinical stage of AD appears to be associated with worse sleep quality but not with changes in sleep quantity.

https://jamanetwork.com/journals/jamaneurology/articlepdf/1663363/noc120110_587_593.pdf

Sleep Quality and Preclinical Alzheimer Disease

BACKGROUND: Results from longitudinal studies on sleep duration and incidence of depression remain controversial. METHODS: PubMed and Web of Science updated on October 22, 2014 were searched for eligible publications. Pooled relative risks (RRs) with 95% confidence interval (CI) were calculated using a random-effects model. RESULTS: Seven prospective studies were included, involving 25,271 participants for short sleep duration and 23,663 participants for long sleep duration. Compared with the normal sleep duration, the pooled RR for depression was 1.31 (95% CI, 1.04-1.64; I(2) = 0%) for the short sleep duration overall. For long sleep duration, the pooled RR was 1.42 (95% CI, 1.04-1.92; I(2) = 0%). The associations between short or long sleep duration and risk of depression did not substantially change in sensitivity and subgroup analyses. No evidence of publication bias was found. CONCLUSION: This meta-analysis indicates that short and long sleep duration was significantly associated with increased risk of depression in adults. Language: en

Sleep duration and depression among adults: a meta-analysis of prospective studies

Sleep is implicated in cognitive functioning in young adults. With increasing age, there are substantial changes to sleep quantity and quality, including changes to slow-wave sleep, spindle density, and sleep continuity/fragmentation. A provocative question for the field of cognitive aging is whether such changes in sleep physiology affect cognition (e.g., memory consolidation). We review nearly a half century of research across seven diverse correlational and experimental domains that historically have had little crosstalk. Broadly speaking, sleep and cognitive functions are often related in advancing age, though the prevalence of null effects in healthy older adults (including correlations in the unexpected, negative direction) indicates that age may be an effect modifier of these associations. We interpret the literature as suggesting that maintaining good sleep quality, at least in young adulthood and middle age, promotes better cognitive functioning and serves to protect against age-related cognitive declines.

/pdf/sleep-cognition-and-normal-aging-integrating-a-half-century-3nsdkjv0vf.pdf

Sleep, cognition, and normal aging: integrating a half century of multidisciplinary research.

Bidirectional relationship between sleep and Alzheimer's disease: role of amyloid, tau, and other factors.

STUDY OBJECTIVES To examine the association between sleep-related factors and memory impairment. DESIGN Cross-sectional study SETTING Community-based study in Guangzhou, China. PARTICIPANTS 28,670 older Chinese (20,776 women and 7,894 men) aged 50 to 85 years. MEASUREMENTS AND RESULTS Demographic and socioeconomic data, sleep-related factors, and cognitive function were collected by face-to-face interview. Potential confounders, such as employment and occupational status, smoking, alcohol and tea use, physical activity, self-rated health, anthropometry, blood pressure, and fasting plasma glucose and lipids were measured. After adjusting for multiple potential confounders, an inverted U-shaped association between sleep duration and delayed word recall test (DWRT) score, a validated measure of memory impairment, was found, with 7 to 8 h of habitual sleep duration showing the highest score (P-values for trend from 3 to 7 h and from 7 to ≥ 10 h were all ≤ 0.001). Compared to sleep duration of 7 h, the adjusted odds ratio for memory impairment from the sleep duration of 3 to 4 or ≥ 10 h was 1.29 (95% confidence interval 1.07-1.56) and 1.52 (1.25-1.86), respectively. Subjects with daily napping, morning tiredness, or insomnia had significantly lower DWRT scores than those without (P ranged from < 0.001 to 0.01). CONCLUSIONS Short or long sleep duration was an important sleep-related factor independently associated with memory impairment and may be a useful marker for increased risk of cognitive impairment in older people.

/pdf/short-or-long-sleep-duration-is-associated-with-memory-3cq7727yp6.pdf

Short or long sleep duration is associated with memory impairment in older Chinese: the Guangzhou Biobank Cohort Study.

Popular Tasks used by Researchers

How can I help with your research?

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

We encountered an error while loading the panel. Please try refreshing the page.

Something went wrong

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

Anyone with the link can view this chat. You can switch it back to private anytime.

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Zhang Ws

Author Tools

Chat about Author

Papers

Short or long sleep duration is associated with memory impairment in older Chinese: the Guangzhou Biobank Cohort Study.