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long sleep duration
Also known as: LSD, prolonged sleep duration
Facts (54)
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Improvement in sleep duration was associated with higher cognitive ... aging-us.com Oct 20, 2020 36 facts
measurementThe mean score for the Long Sleep Duration (LSD) group at Wave 1 was 8.19 with a standard deviation of 4.58.
claimA transition from short sleep duration (SSD) to long sleep duration (LSD) was associated with lower global cognition scores, including on episodic memory, figure drawing, and TICS tests.
measurementA history of stroke was reported by 2.7% of the less than 6 hours sleep group, 1.7% of the 6-8 hours group, and 2.2% of the greater than 8 hours group, with an overall prevalence of 2.1%.
claimSleep duration was categorized into three groups: Short Sleep Duration (SSD) as <6 hours, Medium Sleep Duration (MSD) as 6-8 hours, and Long Sleep Duration (LSD) as >8 hours.
procedureFor subjects with Short Sleep Duration (SSD) in Wave 1, the study classifies change patterns as: 'Excessive' (if there was one wave with Long Sleep Duration), 'No change' (maintained SSD in two waves), 'Benefit 1' (maintained SSD in one wave and had Moderate Sleep Duration in another), and 'Benefit 2' (Moderate Sleep Duration in two waves).
claimShort or long sleep duration can disrupt the circadian rhythm.
claimShort or long sleep duration and the disruption of the circadian rhythm are risk factors for neurodegenerative diseases, including dementia.
measurementThe mean Body Mass Index (BMI) of all participants was 23.4 (standard deviation 3.7), with the less than 6 hours sleep group at 23.0, the 6-8 hours group at 23.6, and the greater than 8 hours group at 23.2.
referenceA meta-analysis revealed an inverted-U-shaped association between sleep duration and the risk of Alzheimer’s disease, where both short sleep duration (SSD) and long sleep duration (LSD) are associated with a higher risk compared to moderate sleep duration (MSD).
claimA transition from long sleep duration (LSD) to short sleep duration (SSD) was associated with lower episodic memory scores.
measurementThe mean age of all participants in the study was 59.1 years (standard deviation 9.8), with the less than 6 hours sleep group having a mean age of 61.0 years, the 6-8 hours group having a mean age of 58.1 years, and the greater than 8 hours group having a mean age of 59.7 years.
measurementA change from short sleep duration to long sleep duration is associated with lower global cognition scores (β=-0.94, P <0.001) in individuals aged 45 and older.
procedureFor subjects with Long Sleep Duration (LSD) in Wave 1, the study classifies change patterns as: 'Excessive' (if there was one wave with Short Sleep Duration), 'No change' (maintained LSD in the two waves), 'Benefit 1' (maintained LSD in one wave and had Moderate Sleep Duration in another), and 'Benefit 2' (Moderate Sleep Duration in two waves).
claimThe Chinese Longitudinal Healthy Longevity Survey reported that a change from long sleep duration (LSD) to moderate sleep duration (MSD) could decrease the risk of dementia.
referenceThe study defines sleep duration categories as Short Sleep Duration (SSD), Moderate Sleep Duration (MSD), and Long Sleep Duration (LSD).
referenceA 2018 systematic review and meta-analysis by Jike et al. investigated the relationship between long sleep duration and various health outcomes.
measurementIn a 2020 study by Q. Zhu involving 5,419 Chinese participants aged 70-90 from the Chinese Longitudinal Healthy Longevity Survey, a change to long sleep duration (LSD) was associated with a higher risk of mild cognitive impairment (MCI) with an odds ratio (OR) of 1.41 to 3.39.
referenceWestwood et al. (2017) published a study in Neurology titled 'Prolonged sleep duration as a marker of early neurodegeneration predicting incident dementia', which suggests that long sleep duration may indicate early neurodegeneration.
measurementLong sleepers, defined as those sleeping more than 8 hours per night in Wave 1, had lower global cognition scores compared to moderate sleepers (6-8 hours) in the study.
measurementThe prevalence of hypertension was 26.7% in the less than 6 hours sleep group, 22.9% in the 6-8 hours group, and 25.5% in the greater than 8 hours group, with an overall prevalence of 24.2%.
measurementThe effect of long sleep duration on global cognition scores was equivalent to being 6 to 11 years older compared to the moderate sleep-duration group.
measurementA change from long sleep duration to short sleep duration is associated with lower global cognition scores (β=-1.38, P <0.01) in individuals aged 45 and older.
measurementThe study categorized 15,216 participants into three sleep duration groups in Wave 1: less than 6 hours (n=4,453), 6 to 8 hours (n=9,508), and greater than 8 hours (n=1,255).
measurementThe use of tranquilizers was reported by 0.6% of the less than 6 hours sleep group, 0.2% of the 6-8 hours group, and 0.0% of the greater than 8 hours group, with an overall prevalence of 0.3%.
measurementAmong participants who slept more than 8 hours in Wave 1, the 'Excessive' sleep group showed lower global cognition in Wave 3 compared to the 'No-change' group (β=-1.38, P<0.01 for model 2; β=-1.17, P<0.01 for model 3), specifically regarding episodic memory.
claimThe Whitehall Study did not obtain significant findings among people with short sleep duration (SSD) and lacked a sufficient sample size of individuals with long sleep duration (LSD).
measurementA history of heart disease was reported by 15.3% of the less than 6 hours sleep group, 11.1% of the 6-8 hours group, and 9.4% of the greater than 8 hours group, with an overall prevalence of 12.1%.
measurementIn a 2011 study by J.E. Ferrie involving 5,431 British participants aged 45-69 from the Whitehall Study, a change to long sleep duration (LSD) was associated with lower cognition with a beta value of -2.74 to -0.72.
measurementCurrent smoking prevalence was 37.2% in the less than 6 hours sleep group, 40.0% in the 6-8 hours group, and 37.2% in the greater than 8 hours group, with an overall prevalence of 39.0%.
measurementIn the study, 8.2% of participants were in the long sleep duration (LSD) group at baseline, and 0.6% of participants remained in the LSD group from Wave 1 to Wave 3.
measurementIn a 2020 study by Q. Zhu involving 5,419 Chinese participants aged 70-90 from the Chinese Longitudinal Healthy Longevity Survey, a change to long sleep duration (LSD) was associated with a lower risk of mild cognitive impairment (MCI) with an odds ratio (OR) of 0.45 to 0.93.
referenceThe Doetinchem Cohort Study, published by van Oostrom et al. in Sleep Medicine (2018), found that long sleep duration is associated with lower cognitive function among middle-aged adults.
measurementThe prevalence of depression among participants was 6.8% for the less than 6 hours sleep group, 6.9% for the 6-8 hours group, and 9.5% for the greater than 8 hours group, with an overall prevalence of 7.1%.
claimFor participants identified as long sleepers in Wave 1, changes in sleep duration had no significant effect on global cognition scores.
measurementIn a 2018 study by Y. Lu involving 7,422 Japanese participants aged 65 or older from the Ohsaki Cohort 2006 study, a change to long sleep duration (LSD) was associated with a higher risk of incident dementia with an odds ratio (OR) of 1.13 to 1.72.
measurementThe study included 232 subjects in the Long Sleep Duration (LSD) group at Wave 1.
U shaped association between sleep duration and long ... nature.com by F Feng · 2025 8 facts
claimSome evidence suggests that prolonged sleep duration (≥ 7.95 hours) may paradoxically increase the risk of cognitive decline in normal elderly individuals.
measurementLong sleep duration of more than 8 hours is associated with a 57% increased odds of cognitive decline (OR = 1.57, 95% CI: 1.31–1.89) after adjusting for potential confounders.
measurementA sensitivity analysis excluding individuals with missing covariate data (n=6366) found that short sleep duration was associated with an adjusted OR of 1.23 for cognitive decline, and long sleep duration was associated with an adjusted OR of 1.47.
referenceYang et al. identified prolonged sleep duration as a predictor of cognitive decline in a meta-analysis encompassing 49 cohort studies.
measurementIn the China Health and Retirement Longitudinal Study (CHARLS), individuals with long sleep duration (> 8 hours) had an odds ratio (OR) of 1.57 (95% CI: 1.31–1.89) for incident cognitive decline.
claimProlonged sleep duration may be an early manifestation of underlying neurodegeneration rather than a causal factor for cognitive decline.
claimThe elevated risk of cognitive decline associated with long sleep duration may be caused by undiagnosed sleep disorders, specifically obstructive sleep apnea syndrome (OSAS) and REM sleep behavior disorder (RBD).
claimProlonged sleep duration is associated with a significantly increased risk of cognitive decline, with a risk magnitude greater than that observed in individuals with insufficient sleep.
Associations Between Sleep Duration and Cognitive Function ... humanfactors.jmir.org 5 facts
claimIn the study using the CHARLS database, the standard sleep duration group exhibited optimal cognitive scores, episodic memory, and mental intactness, while both short and long sleep durations were significantly associated with cognitive decline, with long sleep having a more pronounced negative effect.
claimRisks associated with both short and long sleep duration necessitate individualized sleep health interventions tailored to personal characteristics.
claimLong sleep duration is frequently associated with underlying health conditions, such as elevated inflammatory markers like C-reactive protein and metabolic dysregulation, which may indirectly contribute to cognitive decline.
claimSex differences in physiological, hormonal, and social factors, such as variations in estrogen levels and their neuroprotective effects, may contribute to differing cognitive outcomes between men and women associated with long sleep duration.
claimIn Chinese culture, familial support and traditional health beliefs that promote prolonged rest may exacerbate the negative effects of long sleep duration on older adults by reducing physical activity levels and increasing the prevalence of long sleep.
Why Sleep Matters: Consequences of Sleep Deficiency sleep.hms.harvard.edu 2 facts
Sleep duration, chronotype, health and lifestyle factors ... bmjpublichealth.bmj.com 1 fact
measurementPopulation-based research indicates potential cognitive impairments are associated with both short sleep duration (≤4 hours) and long sleep duration (≥10 hours).
Associations Between Total Sleep Duration and Cognitive Function ... dovepress.com Feb 10, 2022 1 fact
referenceThe Guangzhou Biobank Cohort Study, published in Sleep in 2011, found that both short and long sleep duration are associated with memory impairment in older Chinese adults.
Impact of sleep duration on executive function and brain structure nature.com Mar 3, 2022 1 fact
referenceAuyeung, T. W. et al. found that cognitive deficit is associated with phase advance of sleep-wake rhythm, daily napping, and prolonged sleep duration in a 2013 cross-sectional study of 2,947 community-dwelling older adults published in the journal Age.