Sleep duration and mortality in the elderly: a systematic review with meta-analysis

Association of night-time sleep duration and daytime napping with all-cause and cause-specific mortality in older British men: Findings from the British Regional HeartStudy

Short and long night-time sleep and daytime napping in young and middle-aged populations were associated with increased mortality, but it is unclear in very older people. The aim of this prospective study was to assess the associations in people aged >70 years. We examined the data of British Regional Heart Study, which included 1722 men aged 71-92 years and had night-time sleep duration and daytime napping measured at baseline and were followed up for nine years. There were 597 deaths. Compared to night-time sleep at 7-<8 h, age-adjusted hazard ratio of all-cause mortality in participants sleeping <6 h was 1.04 (95% CI 0.80-1.35), 1.07 (0.85-1.34) in 6-<7 h, 1.04 (0.83-1.30) in 8-<9 h and 0.93 (0.65-1.33) in ≥9 h. Further adjustments for other co-variables still showed no association, and neither the association with cardiovascular mortality nor non-cardiovascular mortality. Daytime napping, however, was associated with mortality. After adjustment for age, smoking, physical activity, obesity, cardiovascular diseases, diabetes, frailty, general health, anti-hypertensive medication and C-reactive protein level, hazard ratio of all-cause mortality in participants with daytime napping >1-h versus no napping was 1.62 (1.18-2.22) and hazard ratio of non-cardiovascular mortality was 1.77 (1.22-2.57). The fully adjusted hazard ratio of cardiovascular mortality was not significantly increased 1.26 (0.69-2.28), although age-adjusted hazard ratio was significant 1.94 (1.20-3.16). In the elderly men, daytime napping was independently associated with increased all-cause and non-cardiovascular mortality, while its association with cardiovascular mortality could be explained by cardiovascular risk factors and co-morbidities. Night-time sleep duration was not associated with mortality risk.

Interventions to Reduce Hospital Readmissions in Older African Americans: A Systematic Review of Studies Including African American Patients

OBJECTIVES

This systematic review aims to summarize interventions that effectively reduced hospital readmission rates for African Americans (AAs) aged 65 and older.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed for this review. Studies were identified by searching PubMed for clinical trials on reducing hospital readmission among older patients published between 1 January 1990 and 31 January 2020. Eligibility criteria for the included studies were mean or median age ≥ 65 years, AAs included in the study, randomized clinical trial or quasi-experimental design, presence of an intervention, and hospital readmission as an outcome.

RESULTS

There were 5270 articles identified and 11 were included in the final review based on eligibility criteria. The majority of studies were conducted in academic centers, were multi-center trials, and included over 200 patients, and 6-90% of participants were older AAs. The length of intervention ranged from 1 week to over a year, with readmission assessed between 30 days and 1 year. Four studies which reported interventions that significantly reduced readmissions included both inpatient (e.g., discharge planning prior to discharge) and outpatient care components (e.g., follow-ups after discharge), and the majority used a multifaceted approach.

CONCLUSION

Findings from the review suggest successful interventions to reduce readmissions among AAs aged 65 and older should include inpatient and outpatient care components at a minimum. This systematic review showed limited evidence of interventions successfully decreasing readmission in older AAs, suggesting a need for research in the area to reduce readmission disparities and improve overall health.

Is there a ubiquitous association between sleep disorder and frailty? findings from LASI (2017-18)

BACKGROUND

Relatively little is known about how sleep disorders affect frailty of seniors. The study uses Fried's frailty index, to investigate the relationship between sleep disorder and frailty among older Indian adults.

METHODS

The study analysed Longitudinal Ageing Study in India (2017-18) data which uses a multistage stratified area probability cluster sampling design. The association between frailty was studied for which the total sample size was 31,902. The principal dependent variable was frailty. Descriptive statistics and cross-tabulation were presented in the study. A binary logistic regression analysis was used to fulfil the study objectives to find the possible association.

RESULTS

The prevalence of frailty in India was 21.3 percent. Older adults with sleep disorder had 66 percent higher likelihood to be frail than their counterparts. The benefits of physical activity in containing frailty is huge, the association were quite high. Poor Self-rated health was significantly associated with higher frailty (OR = 1.73; CI = 1.47-2.04).

CONCLUSIONS

Frailty is an enormously growing public health issue and has bi-directional relation with sleep disorders. The study has clinical relevance since sleep complaints offer a means for identifying those who are vulnerable to frailty and through appropriate intervention, the causes of sleep disorder would help to delay and in some cases reverse frailty.

Sleep measures and cardiovascular disease in type 2 diabetes mellitus

OBJECTIVE

The objective of this study was to assess whether poor sleep is independently associated with cardiovascular disease in people with type 2 diabetes mellitus (T2DM).

METHODS

A cross-sectional study was performed in subjects with T2DM aged between 40 and 80 years. Sleep assessment was achieved by actigraphy and Pittsburgh Sleep Quality Index (PSQI) score.

RESULTS

The study population comprised 108 subjects with T2DM. The mean age was 64.9 years, the median diabetes duration was 6 years and 73.1% were men. No association was shown between sleep parameters as assessed by actigraphy and T2DM-associated micro- and macrovascular complications. However, sleep quality as assessed by PSQI was significantly associated with macrovascular disease in univariate analysis. Multivariate logistic regression analysis showed red blood cell distribution width (RDW) (odds ratio (OR) 1.79, p=0.018) and good sleep quality (OR 0.35, p=0.017) to be independently associated. Binary logistic regression analysis revealed that body mass index (BMI) (OR 1.11, p=0.024), RDW (OR 1.95, p=0.007) and Center for Epidemiologic Studies Depression score (OR 1.06, p=0.012] were independently associated with abnormal carotid intima-media thickness (CIMT).

CONCLUSIONS

Poor sleep quality and higher RDW levels are associated with macrovascular disease in a T2DM population. Increased BMI as well as depression also appear to have an independent role in subclinical atherosclerosis, as assessed by CIMT.

Erwin M, Olmstead R, Jean-Louis G, Parthasarathy S, D. Youngstedt S. Comparisons of Sleep, Demographics, and Health-Related Variables in Older Long and Average Duration Sleepers

Introduction  Long sleep duration is associated with many health risks, particularly in older adults, but little is known about other characteristics associated with long sleep duration. Methods  Across 5 sites, adults aged 60-80 years who reported sleeping 8-9 h ("long sleepers", n = 95) or 6-7.25 h ("average sleepers", n = 103) were assessed for two weeks using actigraphy and sleep diary. Demographic and clinical characteristics, objective sleep apnea screening, self-reported sleep outcomes, and markers of inflammation and glucose regulation were measured. Results  Compared to average sleepers, long sleepers had a greater likelihood of being White and unemployed and/or retired. Long sleepers also reported longer time in bed, total sleep time and wake after sleep onset by sleep diary and by actigraphy. Other measures including medical co-morbidity, apnea/hypopnea index, sleep related outcomes such as sleepiness, fatigue, depressed mood, or markers of inflammation and glucose metabolism did not differ between long and average sleepers. Conclusion  Older adults with long sleep duration were more likely to be White, report unemployment and retirement suggesting the social factors or related sleep opportunity contributed to long sleep duration in the sample. Despite known health risks of long sleep duration, neither co-morbidity nor markers of inflammation or metabolism differed in older adults with long sleep duration compared with those with average sleep duration.

Race and Socioeconomic Status: Interlinked Drivers of Sleep Health Disparities

The effect of race and socioeconomic status on sleep disorders has significant effects on the availability of healthcare and health outcomes. This paper examines how race and SES contribute to sleep health disparities, emphasizing the importance of understanding their impact on sleep disorders and treatment particularly in minority populations and veterans.

The relationship between processing speed and remodeling spatial patterns of intrinsic brain activity in the elderly with different sleep duration

Objective

Brain neuroplasticity in which sleep affects the speed of information processing in the elderly population has not been reported. Therefore, this study was conducted to explore the effects of sleep on information processing speed and its central plasticity mechanism in the elderly.

Methods

A total of 50 individuals aged 60 and older were enrolled in this case control study. All subjects were divided into two groups according to the sleep time: short sleep duration (< 360 min) (6 men and 19 women; mean age: 66.96 ± 4.28 years old), and non-short sleep duration (> 360 min) (13 men and 12 women). Resting-state functional magnetic resonance imaging (rs-fMRI) data were collected, and the amplitude of low frequency fluctuation (ALFF), regional homogeneity (ReHo), and degree centrality (DC) were calculated for each participant. Two-sample t-tests were performed to compare the ALFF, ReHo, and DC maps between the two groups. Then, the relationships among clinical features, fMRI and cognitive function were analyzed using general linear model.

Results

Short sleep duration group showed significantly increased ALFF value in the bilateral middle frontal gyrus and right insula; significantly increased ReHo value in the left superior parietal gyrus, and decreased ReHo value in the right crebellum; significantly decreased DC value in the left inferior occipital gyrus, left superior parietal gyrus and right cerebellum (p < 0.05, AlphaSim correction). The ALFF value of right insula is significantly associated with symbol digit modalities test (SDMT) score (β = -0.363, p = 0.033).

Conclusion

Short sleep duration and processing speed are significantly associated with remodeling spatial patterns of intrinsic brain activity in the elderly.

Provider Perspectives on Sleep as a Determinant of Health and Housing Outcomes among Veterans Experiencing Homelessness: An Exploratory, Social-Ecological Study

Sleep problems are common among United States (U.S.) veterans and are associated with poor health, mental health, and functioning. Yet, little is known about insufficient sleep and factors contributing to sleep disparities among veterans experiencing homelessness. We conducted semi-structured interviews to better understand the clinical, environmental, and structural factors contributing to insufficient sleep among veterans and to improve care for this population. Interviews were conducted with 13 providers caring for veterans experiencing homelessness, including physicians, psychologists, nurses, social workers, and peer support specialists. Providers worked at a West Coast VA institution serving a large population of veterans experiencing homelessness. Interviews were analyzed for themes pertaining to sleep using the social-ecological model as a framework. On an individual level, factors influencing sleep included psychiatric disorders and use of substances. On an interpersonal level, factors included safety concerns while sleeping. On an environmental level, factors included noise and proximity to others as barriers to sleep. On the organizational level, logistical issues scheduling sleep clinic appointments and lack of transportation to attend sleep clinic appointments were identified as treatment barriers. These findings can inform future research studying the impact of sleep on health and housing outcomes and interventions addressing sleep among veterans experiencing homelessness.

Mortality was predicted by depression and functional dependence in a cohort of elderly adults of Italian descent from southern Brazil

The older population has an increasing burden of non-communicable disease, which can potentially be associated with physical and mental disabilities and shorten life spam. To investigate whether depression, loss of functionality for activities of daily living, and lower social support are associated with all-cause mortality in the older population of Italian descent. This population-based cohort study was conducted in Veranópolis, a country city from southern Brazil, among individuals aged 60 years or older. Interviews were performed in a systematic random sampling regarding demographic, socioeconomic, and psychosocial variables, in addition to depression (Geriatric Depression Scale), activities of daily living (Barthel Index), and social support (Medical Outcomes Study scale). In the follow-up, participants were reinterviewed or, in case of death, the next of kin, and hospital records were revised. Hierarchical analysis was used to determine characteristics independently associated with all-cause mortality, using Poisson regression with robust variance, expressed as relative risk with 95% confidence intervals (RR; 95%CI). A total of 997 participants were enrolled and 882 participants completed the study, after 7.24 ± 2.41 years; with 581 remaining alive. The mean age was 73.12 ± 8.03 years, 4% were nonagenarians or centennials, and 62% were women. Symptoms of depression (RR: 1.04; 1.01-1.06) and functional dependence for ADL (RR: 1.00; 0.99-1.00) were associated with all-cause mortality, even after controlling for confounding factors. Lower social support was not associated with mortality (RR: 1.00; 0.99-1.01). Depression and functional dependence are independent predictors of all-cause mortality in the older population from Italian descent.

Childhood health conditions and insomnia among adults in mid-life

Background

Little is known regarding the influence of childhood health broadly and childhood health conditions specifically on insomnia throughout adulthood.

Methods

Health and Retirement Study (HRS) Baby Boomers born 1954-1965 were investigated. We fitted regression models predicting self-reported insomnia based on twenty-three retrospectively reported specific childhood health conditions (e.g., measles) and general childhood health measures and adjusted for demographics, childhood socioeconomic status, and adult socioeconomic status.

Results

Nearly all the measures of childhood health significantly increased insomnia symptoms in adulthood. In a model where all measures were included, we found that respiratory disorders, headaches, stomach problems, and concussions were particularly strong predictors of insomnia.

Conclusions

Our findings extend past work illustrating the "long arm" of childhood conditions for health, showing that specific health conditions in childhood may indelibly imprint insomnia risk.

Sleep duration, hypnotic drug use, and risk factors: cross- sectional study

Both short sleep duration (SSD) and long sleep duration (LSD) are associated with an increased risk of morbidity and mortality. Here, we aimed to assess the prevalence of sleep duration disturbances among adults in association with demographic, medication use, personal habits, and chronic diseases, while also considering the impact of hypnotic drug use. We performed a cross-sectional study of 9991 adult participants of the Rafsanjan Cohort Study (RCS), as part of the Prospective epidemiological research studies in Iran (PERSIAN). Multivariate logistic regression analyses were conducted to assess the association between short (< 6 h) and long (> 9 h) sleep duration with demographic and lifestyle parameters and common non-communicable diseases. Additionally, we performed stratified analysis to investigate the association of sleep duration with the abovementioned factors and diseases, in groups with and without hypnotic drug use. We found higher odds of SSD significantly associated with age (P < 0.001), BMI (P < 0.001), physical activity (P < 0.001), and depression (P = 0.023). LSD displayed a positive association with the female sex (P < 0.001), opium consumption (P < 0.001), and history of MI (P = 0.045), and a reverse connection with education (P = 0.007), physical activity (P < 0.001) and alcohol consumption (P = 0.027). Stratifying for the hypnotic drug use, our sensitivity analyses indicated that in hypnotic drug users, education (P = 0.034) and physical activity (P < 0.001) were associated with LSD, in this group, significantly increased odds ratio of LSD were associated with opium consumption (P = 0.046) and thyroid dysfunction (P = 0.037). Our findings demonstrated the demographic and lifestyle factors and diseases associated with long and short sleep duration in the population of the RCS. Additionally, after stratifying for hypnotic drug use, our results indicated that some diseases are only associated with abnormal sleep duration upon using hypnotic drugs.

The relationship between sleep duration and activities of daily living (ADL) disability in the Chinese oldest-old: A cross-sectional study

Objective

To investigate the relationship between sleep duration and activities of daily living (ADL) disability, and to explore the optimal sleep duration among oldest-old Chinese individuals.

Methods

In this cross-sectional study, 1,798 participants (73.2% female) were recruited from Dongxing and Shanglin in Guangxi Zhuang Autonomous Region, China in 2019. The restricted cubic spline function was used to assess the dose-response relationship between sleep duration and ADL disability, and the odds ratios (ORs) of the associations were estimated by logistic regression models.

Results

The overall prevalence of ADL disability was 63% (64% in females and 58% in males). The prevalence was 71% in the Han population (72% in females and 68% in males), 60% in the Zhuang population (62% in females and 54% in males) and 53% in other ethnic population (53% in females and 53% in males). A nonlinear relationship between sleep duration and ADL disability was observed. Sleep duration of 8-10 hours was associated with the lowest risk of ADL disability. Sleep duration (≥12 hours) was associated with the risk of ADL disability among the oldest-old individuals after adjusting for confounding factors (OR = 1.47, 95% CI [1.02, 2.10], p < 0.05).

Conclusion

Sleep duration more than 12 hours may be associated with an increased risk of ADL disability in the oldest-old individuals, and the optimal sleep duration among this population could be 8-10 h.

Sleep, circadian rhythm characteristics, and melatonin levels in later life adults with and without coronary artery disease

STUDY OBJECTIVES

The purpose of this study was to conduct a comprehensive assessment of sleep and circadian rhythms in individuals with and without coronary artery disease (CAD).

METHODS

This was a cross-sectional study. Participants were 32 individuals, mean age = 70.9, female 46.9%, 19 with CAD, and 13 without CAD. We assessed sleep quality and 24-hour rest-activity rhythms for 14 days using wrist actigraphy and self-report measures, and circadian rhythm using dim light melatonin onset.

RESULTS

Melatonin levels prior to habitual bedtime were significantly lower in individuals with CAD than in those without CAD (median area under the curve = 12.88 vs 26.33 pg/ml × h, P = .049). The median circadian timing measured by dim light melatonin onset was the same for the 2 groups with 20:26 [hours:minutes] for individuals with CAD and 19:53 for the control group (P = .64, r = .14). Compared to the control group, the CAD group had significantly lower amplitude (P = .03, r =-.48), and lower overall rhythmicity (pseudo-F-statistic P = .004, r = -.65) in their 24-hour rest-activity rhythms.

CONCLUSIONS

This is one of the first studies to comprehensively assess both sleep and circadian rhythm in individuals with CAD. Compared to non-CAD controls, individuals with CAD had lower levels of melatonin prior to habitual bedtime and a lower 24-hour rest-activity rhythm amplitude and overall rhythmicity. Future studies using larger sample sizes should further investigate the possibility of suppressed circadian rhythmicity in individuals with CAD.

CITATION

Moon C, Benson CJ, Albashayreh A, Perkhounkova Y, Burgess HJ. Sleep, circadian rhythm characteristics, and melatonin levels in later life adults with and without coronary artery disease. J Clin Sleep Med. 2023;19(2):283-292.

Race/ethnicity, sleep duration, and mortality risk in the United States

Current evidence and professional guidance recommend sleeping between 7 and 9 h in a 24-h period for optimal health. The present study examines the association between sleep duration and mortality and assesses whether this association varies by racial/ethnic identity for a large and diverse sample of United States adults. We use data on 274,836 adults, aged 25 and older, from the 2004-2014 waves of the National Health Interview Survey (NHIS) linked to prospective mortality through 2015 (23,382 deaths). Cox proportional hazards models were used in multi-variable regressions to estimate hazard ratios for mortality by sleep duration and racial/ethnic identity, controlling for sociodemographic, socioeconomic, and psychological distress variables. We find elevated risks of mortality from any cause for adults who sleep less than 5 h or more than 9 h in a 24-h period after all adjustments. Further, we find evidence that these elevated risks for mortality are more pronounced for some racial/ethnic groups and less pronounced for others. Improved understanding of differences in sleep duration and sleep health can facilitate more effective and culturally-tailored interventions around sleep health, improving overall well-being and enhancing longevity.

Relationship of sleep duration with incident cardiovascular outcomes: a prospective study of 33,883 adults in a general population

BACKGROUND

Studies on the effect of sleep duration on cardiovascular health have contradictory findings. Underlying health issues may have led to inconsistent results and warrant consideration. We aim to assess the relationship of night sleep duration with incident cardiovascular disease (CVD) in a general population, taking into consideration underlying chronic diseases.

METHODS

Data from Shanghai Suburban Adult Cohort and Biobank with a median follow-up of 5.1 years was used, including 33,883 adults aged 20-74 years old. Incident CVD cases were reported and recorded by the Center for Disease Prevention and Control in Songjiang, Shanghai. We used Cox proportional hazard regression models and restricted cubic spline (RCS) analysis to explore the relationship between different sleep groups and sleep duration with incident CVD outcomes, through stratification by gender and age, as well as different health conditions, with adjustments for potential confounders.

RESULTS

Long sleep duration (> 9 h) compared to > 7 to ≤ 8 h was associated with overall incident CVD in participants aged ≥ 50 years old: HR(95%CI) = 2.07 (1.15, 3.74) for 50-59y and 1.43 (1.04, 1.93) for 60-74y. RCS analysis showed a J-shaped relationship between sleep and CVD risk in those ≥ 50y, which was confirmed only in those with a chronic health condition. Non-linear relationships between sleep and CVD risk factors, such as BMI, blood glucose and glycated haemoglobin, were observed.

CONCLUSIONS

Long sleep duration is associated with increased risk of CVD in people ≥ 50y. However, CVD risk factors and underlying health conditions such as hypertension, and diabetes, may play a driving role in the relationship.

Prevalence and associated factors of poor sleep quality among Chinese retirees: A multicenter cross-sectional study

BACKGROUND

Sleep problems are common among older adults worldwide. The present study aims to determine the prevalence of poor sleep quality and its independent factors among retired people in health check-ups population in China.

METHOD

In this multicenter, cross-sectional survey in 2017, a group of retired people was invited to participate in an online survey of health status, and their data, including socio-demographic information, lifestyle, and medical characteristics, were recorded. Binary logistic regression was used to analyze the independent factors responsible for poor sleep quality.

RESULTS

Data from 17,408 responders who met the inclusion criteria were analyzed; among them, 53.04 % (95 % CI = 52 %-54 %) reported poor sleep quality. Binary logistic regression showed that poor sleep quality was associated with a number of factors, including being female (OR = 1.42, 95 % CI = 1.32-1.53), being single (OR = 1.35, 95 % CI = 1.18-1.54), non-smoker (OR = 1.12, 95 % CI = 1.03-1.22), physical inactivity (OR = 1.14, 95 % CI = 1.05-1.23), poor self-rated health status (OR = 1.69, 95 % CI = 1.43-2.00), long-term medication use (OR = 1.05, 95 % CI = 1.07-1.23), chronic pain (OR = 1.33, 95 % CI = 1.22-1.45), comorbidity (OR = 1.16, 95 % CI = 1.07-1.25), and depressive symptoms (mild depression: OR = 2.14, 95 % CI = 1.96-2.34; moderate depression: OR = 4.00, 95 % CI = 3.49-4.58, moderately severe depression: OR = 4.15, 95 % CI = 3.47-4.97, severe depression: OR = 4.27, 95 % CI = 2.93-6.22); while age (OR = 0.99, 95 % CI = 0.99-1.00) was negatively related to poor sleep quality.

CONCLUSION

The prevalence of poor sleep quality in the studied population is relatively high (53.04 %). Sleep problems are common among Chinese retirees, especially older females, and have a great impact on their quality of life. People living with depression, chronic diseases, and chronic pain were at a higher risk of developing sleep disorders. Therefore, it is critical to formulate effective management strategies for Chinese retirees with poor sleep quality in the context of healthy aging.

Long Sleep Duration Increases the Risk of All-Cause Mortality Among Community-Dwelling Older Adults With Frailty: Evidence From NHANES 2009-2014

Objectives: The aim of this study was to determine the effect of sleep duration on all-cause mortality among older adults with frailty. Methods: The prospective cohort study included 5705 community participants aged 60 or above in the National Health and Nutrition Examination Survey (NHANES). Health indicators were selected in the NHANES to obtain the frailty index and sleep duration. The risk of all-cause mortality was estimated by a Cox proportional hazard model. Results: During the follow-up, long sleep duration was associated with higher all-cause mortality (adjusted HR = 1.28, 95% CI 1.03-1.59). The hazard of all-cause mortality was the lowest from the beginning of sleep until sleep duration reached 5.8 hours among older adults with frailty. Discussion: Long sleep duration was associated with higher all-cause mortality among older adults with frailty. There was a U-shaped relationship between sleep duration and all-cause mortality.

Sleep pattern and predictors of daily versus as-needed hypnotics use in middle-aged and older adults with insomnia

Introduction

This study aims to examine the sleep pattern and predictors of daily vs. as-needed use of hypnotics in middle-aged and older adults with insomnia.

Methods

Patients aged 50–75 who use hypnotics for insomnia were identified via electronic medical records and were recruited. Data about sociodemographics, mood and cognitive screening measures, and questions related to sleep patterns were collected through an interview conducted over the phone.

Results

A sample of 66 participants was recruited, of which 69.7% were females. Three quarters (49/66, 74.2%) used hypnotics daily, with 43% (21/49) of daily hypnotics users sleeping more than 8 h per night. Two-fifths (26/66, 39.4%) of participants still had clinically significant insomnia even after taking hypnotics. After adjusting for age, years of hypnotics use, sleeping hours per night, PHQ-2 score, and frequency of pain at night, the logistic regression model showed that younger age (p = 0.023) and longer sleeping hours per night (p = 0.025) were significantly associated with daily hypnotics use when compared to as needed hypnotics use.

Conclusion

Many hypnotic users still have clinically significant insomnia and poor quality of sleep as reflected by perceived longer sleep duration and more daytime napping which could be related to drug-related residual sedation. Hypnotic use may not be the best solution for insomnia treatment in an older population, and physicians should regularly reassess the use of hypnotics.

The association between subjective-objective discrepancies in sleep duration and mortality in older men

A discrepancy in subjective and objective estimations of sleep duration, which often diverge, could have long-term adverse effects on health outcomes in older adults. Using data from 2674 older adult men (≥ 65 years of age) of the Osteoporotic Fractures in Men Sleep Study, we assessed the longitudinal association between misperception index (MI), calculated as MI = (objective sleep duration - subjective sleep duration)/objective sleep duration, and all-cause mortality. During the follow-up with a mean (standard deviation) of 10.8 (4.2) years, 1596 deaths were observed. As a continuous variable, MI showed a linear relationship with all-cause mortality after adjusting for multiple covariates, including polysomnography-measured objective sleep duration [fully adjusted hazard ratio (HR), 0.69; 95% confidence interval [CI], 0.56-0.84]. As a categorical variable, the lowest MI quartile (vs. the interquartile MI range) was associated with increased mortality (fully adjusted HR, 1.28; 95% CI, 1.12-1.46), whereas the highest MI quartile was not associated with mortality (fully adjusted HR, 0.97; 95% CI, 0.85-1.11). The subjective overestimation of sleep duration may be a risk factor for all-cause mortality in older men. Future studies should examine why subjective overestimation of sleep duration is associated with all-cause mortality from a physiological perspective.

Opposing inflammatory biomarker responses to sleep disruption in cancer patients before and during oncological therapy

Background

Sleep disruption is known to be highly prevalent in cancer patients, aggravated during oncological treatment and closely associated with reduced quality of life, therapeutic outcome and survival. Inflammatory factors are associated with sleep disruption in healthy individuals and cancer patients, but heterogeneity and robustness of inflammatory factors associated with sleep disruption and how these are affected by oncological therapy remain poorly understood. Furthermore, due to the complex crosstalk between sleep-, and therapy-associated factors, including inflammatory factors, there are currently no established biomarkers for predicting sleep disruption in patients undergoing oncological therapy.

Methods

We performed a broad screen of circulating biomarkers with immune-modulating or endocrine functions and coupled these to self-reported sleep quality using the Medical Outcomes Study (MOS) sleep scale. Ninety cancer patients with gastrointestinal, urothelial, breast, brain and tonsillar cancers, aged between 32 and 86 years, and scheduled for adjuvant or palliative oncological therapy were included. Of these, 71 patients were evaluable. Data was collected immediately before and again 3 months after onset of oncological therapy.

Results

Seventeen among a total of 45 investigated plasma proteins were found to be suppressed in cancer patients exhibiting sleep disruption prior to treatment onset, but this association was lost following the first treatment cycle. Patients whose sleep quality was reduced during the treatment period exhibited significantly increased plasma levels of six pro-inflammatory biomarkers (IL-2, IL-6, IL-12, TNF-a, IFN-g, and GM-CSF) 3 months after the start of treatment, whereas biomarkers with anti-inflammatory, growth factor, immune-modulatory, or chemokine functions were unchanged.

Conclusion

Our work suggests that biomarkers of sleep quality are not valid for cancer patients undergoing oncological therapy if analyzed only at a single timepoint. On the other hand, therapy-associated increases in circulating inflammatory biomarkers are closely coupled to reduced sleep quality in cancer patients. These findings indicate a need for testing of inflammatory and other biomarkers as well as sleep quality at multiple times during the patient treatment and care process.

Associations between sleep patterns, smoking, and alcohol use among older adults in Canada: Insights from the Canadian Longitudinal Study on Aging (CLSA)

Poor sleep is associated with chronic health conditions among older adults. As substance use rates increase in this population, age-related physiological and cognitive declines may exacerbate its detrimental consequences, including sleep problems. We analyzed cross-sectional associations between sleep patterns, smoking, and alcohol use using baseline data from 30,097 community-dwelling Canadian adults aged 45-85 years from the Canadian Longitudinal Study on Aging. Insomnia symptoms (difficulties falling/staying asleep), sleep duration (short:<6h; long:>8h), and sleep satisfaction(dissatisfied/neutral/satisfied) were measured. Smoking and alcohol-use frequency (past 12 months), average daily amount (past 30 days), and binge drinking (past 12 months) were self-reported, and associations were examined using modified Poisson regression. Approximately 23% of participants had insomnia symptoms, and 26% reported sleep dissatisfaction. 91% of participants were current non-smokers, whereas 7% reported smoking daily. Over 50% drank ≤ 2 drinks daily, and 3% reported binge drinking. There was a higher adjusted prevalence of insomnia among daily smokers (PR = 1.10, 95% CI = 1.00-1.21) and binge drinkers (PR = 1.21, 95% CI = 1.02-1.43). Odds of short sleep duration were lower among regular drinkers (COR = 0.71, 95% CI = 0.56-0.90) and higher among daily smokers (COR = 1.19, 95% CI = 1.01-1.40). Heavy and frequent smoking and alcohol use are associated with both insomnia symptoms and sleep dissatisfaction, but not consistently with sleep duration. Further longitudinal investigation of this relationship in aging populations is needed in clinical and public health settings to infer the extent of causality and design effective public health interventions in this vulnerable population.

Daytime napping and cardiovascular risk factors, cardiovascular disease, and mortality: A systematic review

Associations between night sleep duration and cardiovascular risk factors in adults have been well documented. However, the associations for daytime napping remain unclear. In this review, six databases were searched for eligible publications to April 8, 2022. A total of 11 articles were identified for umbrella review on the association of daytime napping with diabetes, metabolic syndrome (MetS), cardiovascular disease (CVD), and mortality in adults, 97 for systematic review on the association with CVD and several CVD risk factors. Our umbrella review showed that the associations of daytime napping with diabetes, MetS, CVD, and mortality in most meta-analyses were mainly supported by weak or suggestive evidence. Our systematic review showed that long daytime napping (≥1 h/d) was associated with higher odds of several CVD risk factors, CVD, and mortality, but no significant association was found between short daytime napping and most of the abovementioned outcomes. Our dose-response meta-analyses showed that daytime napping <30 min/d was not significantly associated with higher odds of most CVD risk factors and CVD among young and middle-aged adults. However, among older adults aged >60 years, we observed significant dose-response associations of daytime napping with higher odds of diabetes, dyslipidemia, MetS, and mortality starting from 0 min/d.

Associations between sleep duration and cardiovascular diseases: A meta-review and meta-analysis of observational and Mendelian randomization studies

The associations between sleep duration and cardiovascular diseases (CVDs) have been explored in many observational studies. However, the causality of sleep duration and many CVDs, such as coronary artery disease (CAD), heart failure (HF), and stroke, remains unclear. In this study, we conducted a systematic meta-review and meta-analysis of the results of observational and Mendelian randomization (MR) studies to examine how sleep duration impacts the risk of CVDs. We searched articles published in English and before 10 September 2021 in PubMed, Web of Science, and Embase. The articles were screened independently by two reviewers to minimize potential bias. We combined the meta-analyses of observational studies and 11 MR studies and summarized evidence of the effect of sleep duration on the risk of CAD, HF, stroke, and cardiovascular and all-cause mortality. Results showed that (a) evidence is accumulating that short sleep duration is a causal risk factor for CAD and HF; (b) abundant evidence from observational studies supports that long sleep duration is associated with the risk of CAD, stroke, and mortality, and long sleep duration has no causal associations with stroke and CAD in the MR studies; the causation of long sleep duration and other CVDs should be further studied; and (c) emerging evidence indicates that an increase in hours of sleep is associated with a decreased risk of CAD. Finally, we discussed the underlying pathophysiological mechanisms underlying short sleep duration and CVDs and suggested that increasing sleep duration benefits cardiovascular health.

Sleep Quality Predicts Functional Disability in Older Adults with Low Back Pain: A Longitudinal Study

Low back pain (LBP) and sleep quality are two very prevalent complaints in the older population. However, little is known about the prognostic relationship between sleep quality and disability in older adults with LBP. The aim of this study was to examine the association between sleep quality and disability in older adults with LBP. This was a longitudinal study over a 6-month period. Older adults with LBP in the last 12 weeks and who had preserved cognitive functions were recruited. The questionnaires used were the Pittsburgh Sleep Quality Index and the Roland Morris Disability Questionnaire. At baseline, we collected information on demographic/anthropometric variables, cognitive status, depression, daytime sleepiness, and comorbidities. Linear regression adjusted for potential covariates were performed. Poor sleep at baseline predicted higher disability after 6 months [β = 0.30 (CI95%:0.07 to 0.55)]. Our results support the existence of an important relationship between sleep and disability in older adults with LBP.

Healthy Lifestyle Score Including Sleep Duration and Cardiovascular Disease Risk

INTRODUCTION

Although insufficient or prolonged sleep duration is associated with cardiovascular disease, sleep duration is not included in most lifestyle scores. This study evaluates the relationship between a lifestyle score, including sleep duration and cardiovascular disease risk.

METHODS

A prospective analysis among 67,250 women in the Nurses' Health Study and 29,114 men in Health Professionals Follow-up Study (1986-2016) was conducted in 2021. Lifestyle factors were updated every 2-4 years using self-reported questionnaires. The traditional lifestyle score was defined as not smoking, having a normal BMI, being physically active (≥30 minutes/day of moderate physical activity), eating a healthy diet, and drinking alcohol in moderation. Low-risk sleep duration, defined as sleeping ≥6 to <8 hours/day, was included as an additional component in the updated lifestyle score. Cox proportional hazard regression models were used to estimate cardiovascular disease risk. The likelihood-ratio test and C-statistics were used to compare both scores.

RESULTS

A total of 11,710 incident cardiovascular disease cases during follow-up were documented. The multivariable-adjusted hazard ratios comparing 6 with 0 low-risk factors in the healthy lifestyle score including sleep duration were 0.17 (95% CI=0.12, 0.23) for cardiovascular disease, 0.14 (95% CI=0.10, 0.21) for coronary heart disease, and 0.20 (95% CI=0.12, 0.33) for stroke. Approximately 66% (95% CI=56%, 75%) of cardiovascular disease, 67% (95% CI=54%, 77%) of coronary heart disease, and 62% (95% CI=42%, 76%) of stroke cases were attributable to poor adherence to a healthy lifestyle including sleep. Adding sleep duration to the score slightly increased the C-statistics from 0.64 (95% CI=0.63, 0.64) to 0.65 (95% CI=0.64, 0.65) (p<0.001).

CONCLUSIONS

Adopting a healthy lifestyle including sleep recommendations could substantially reduce the risk of cardiovascular disease in U.S. adults.

Examining the Relationships Between Sleep Physiology and the Gut Microbiome in Preclinical and Translational Research: Protocol for a Scoping Review

BACKGROUND

Sleep is an instrumental behavioral state with evidence supporting its active role in brain function, metabolism, immune function, and cardiovascular systems. Research supports that there are pathways underlying the bidirectional communication between the brain and gastrointestinal system, also known as the "gut-brain axis." Primary research examining sleep and gut microbiome relationships continues to increase. Although current data include both preclinical and clinical research, gut microbiome results are reported through a wide range of metrics (alpha diversity, beta diversity, and bacterial compositional changes), which makes cross-study comparison challenging. Therefore, a synthesis of the research examining sleep and gut microbiome relationships is necessary to understand the state of the science and address gaps in the literature for future research.

OBJECTIVE

In this paper, we outline a scoping review protocol to evaluate and synthesize preclinical and clinical primary research focused on the associations between sleep and the gut microbiome.

METHODS

The search strategy was facilitated through a medical research librarian and involved electronic databases including PubMed/MEDLINE, Embase, Scopus, Web of Science, CENTRAL trials database, BIOSIS Citation Index, and the Zoological Record. Gray literature sources including medRxiv and bioRxiv preprint servers were also searched. Studies were screened according to the aims and exclusion and inclusion criteria of the protocol. After screening, data will be extracted and synthesized from the included studies according to predefined sleep and microbiome methodology metrics.

RESULTS

The search strategy yielded 4622 references that were imported for study screening, and source screening was completed in May 2022 by 2 independent investigators, resulting in a total of 93 sources for data extraction and synthesis. The data synthesis table is expected to be completed by August 2022, and the results will be disseminated through paper submission by December 2022 and presented at conferences related to neuroscience, sleep physiology, bioinformatics, and the microbiome.

CONCLUSIONS

A scoping review of preclinical and clinical research is needed to synthesize the growing data focused on the relationships between sleep and the gut microbiome. We expect the results of this synthesis will identify gaps in the literature and highlight pathways linking the gut-brain axis and sleep physiology to stimulate future research questions.

TRIAL REGISTRATION

Open Science Framework 69TBR; https://osf.io/69tbr.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/38605.

Sleep Deficiency and Cardiometabolic Disease

Epidemiologic studies have demonstrated that short sleep duration is associated with an increased risk of cardio-metabolic health outcomes including cardiovascular disease mortality, coronary heart disease, type 2 diabetes mellitus, hypertension, and metabolic syndrome. Experimental sleep restriction studies have sought to explain these findings. This review describes the main evidence of these associations and possible mechanisms explaining them. Whether sleep extension reverses these now widely acknowledged adverse health effects and the feasibility of implementing such strategies on a public health level is discussed.

Comparison of Time-Frequency Analyzes for a Sleep Staging Application with CNN

Sleep staging is the process of acquiring biological signals during sleep and marking them according to the stages of sleep. The procedure is performed by an experienced physician and takes more time. When this process is automated, the processing load will be reduced and the time required to identify disease will also be reduced. In this paper, 8 different transform methods for automatic sleep-staging based on convolutional neural networks (CNNs) were compared to classify sleep stages using single-channel electroencephalogram (EEG) signals. Five different labels were used to stage the sleep. These are Wake (W), Non Rapid Eye Movement (NonREM)-1 (N1), NonREM-2 (N2), NonREM-3 (N3), and REM (R). The classifications were done end-to-end without any hand-crafted features, ie without requiring any feature engineering. Time-Frequency components obtained by Short Time Fourier Transform, Discrete Wavelet Transform, Discrete Cosine Transform, Hilbert-Huang Transform, Discrete Gabor Transform, Fast Walsh-Hadamard Transform, Choi-Williams Distribution, and Wigner-Willie Distribution were classified with a supervised deep convolutional neural network to perform sleep staging. The discrete Cosine Transform-CNN method (DCT-CNN) showed the highest performance among the methods suggested in this paper with an F1 score of 89% and a value of 0.86 kappa. The findings of this study revealed that the transformation techniques utilized for the most accurate representation of input data are far superior to traditional approaches based on manual feature extraction, which acquires time, frequency, or nonlinear characteristics. The results of this article are expected to be useful to researchers in the development of low-cost, and easily portable devices.

Mortality associated with nonrestorative short sleep or nonrestorative long time-in-bed in middle-aged and older adults

Associations of sleep duration with human health could differ depending on whether sleep is restorative. Using data from 5804 participants of the Sleep Heart Health Study, we examined the longitudinal association of sleep restfulness combined with polysomnography-measured total sleep time (TST) or time in bed (TIB), representing different sleeping behaviors, with all-cause mortality. Among middle-aged adults, compared with restful intermediate TST quartile, the lowest TST quartile with feeling unrested was associated with higher mortality (hazard ratio [HR], 1.54; 95% confidence interval [CI] 1.01–2.33); the highest TST quartile with feeling rested was associated with lower mortality (HR, 0.55; 95% CI 0.32–0.97). Among older adults, the highest TIB quartile with feeling unrested was associated with higher mortality, compared with restful intermediate TIB quartile (HR, 1.57; 95% CI 1.23–2.01). Results suggest a role of restorative sleep in differentiating the effects of sleep duration on health outcomes in midlife and beyond.

A cluster analysis of device-measured physical activity behaviours and the association with chronic conditions, multi-morbidity and healthcare utilisation in adults aged 45 years and older

Most adults do not meet physical activity guidelines with negative implications for health. The aim of this study was to profile adults using multiple physical activity behaviours and to investigate associations with chronic conditions, multi-morbidity and healthcare utilisation. The study used data generated from a sample of adults aged 45 years and older (N = 485), recruited to the Move for Life randomised control trial. Participants wore an accelerometer for eight consecutive days. Hierarchical cluster analysis was conducted using the variables: moderate to vigorous intensity physical activity, light intensity physical activity, step count, waking sedentary time, standing time and bed hours. Descriptive statistics were used to investigate associations with self-reported number of chronic illnesses, multi-morbidity and healthcare utilisation. Four distinct physical activity behaviour profiles were identified: inactive-sedentary (n = 50, 10.3%), low activity (n = 295, 60.8%), active (n = 111, 22.9%) and very active (n = 29, 6%). The inactive-sedentary cluster had the highest prevalence of chronic illnesses, in particular, mental illness (p = 0.006) and chronic lung disease (p = 0.032), as well as multi-morbidity, complex multi-morbidity and healthcare utilisation. The prevalence of any practice nurse visit (p = 0.033), outpatient attendances (p = 0.04) and hospital admission (p = 0.034) were higher in less active clusters. The results have provided an insight into how physical activity behaviour is associated with chronic illness and healthcare utilisation. A group within the group has been identified that is more likely to be unwell. Provisions need to be made to reduce barriers for participation in physical activity for adults with complex multi-morbidity and very low physical activity.

Self-reported sleep characteristics associated with dementia among rural-dwelling Chinese older adults: a population-based study

BACKGROUND

Sleep characteristics associated with dementia are poorly defined and whether their associations vary by demographics and APOE genotype among older adults are unclear.

METHODS

This population-based cross-sectional study included 4742 participants (age ≥ 65 years, 57.1% women) living in rural China. Sleep parameters were measured using the self-rated questionnaires of the Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale. Global cognitive function was assessed with the Mini-Mental State Examination (MMSE). Dementia was diagnosed following the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria, and the National Institute on Aging-Alzheimer's Association criteria for Alzheimer's disease (AD). Data were analysed using multiple logistic and general linear regression models.

RESULTS

Dementia was diagnosed in 173 participants (115 with AD). Multivariable-adjusted odds ratio (OR) of dementia was 1.71 (95%CI, 1.07-2.72) for sleep duration ≤4 h/night (vs. > 6-8 h/night), 0.76 (0.49-1.18) for > 4-6 h/night, 1.63 (1.05-2.55) for > 8 h/night, 1.11 (1.03-1.20) for lower sleep efficiency (per 10% decrease), and 1.85 (1.19-2.89) for excessive daytime sleepiness. Very short sleep duration (≤4 h/night), lower sleep efficiency, and excessive daytime sleepiness were significantly associated with being diagnosed with AD (multivariable-adjusted OR range = 1.12-2.07; p < 0.05). The associations of sleep problems with dementia and AD were evident mainly among young-old adults (65-74 years) or APOE ε4 carriers. Among dementia-free participants, these sleep characteristics were significantly associated with a lower MMSE score.

CONCLUSIONS

Self-reported sleep problems in dementia are characterized by very short or long sleep duration, low sleep efficiency, and excessive daytime sleepiness, especially among young-old people and APOE ε4 carriers.

TRIAL REGISTRATION

ChiCTR1800017758 (Aug 13, 2018).

Association between Sleep Duration and Depression among the Elderly Population in China

OBJECTIVES

The objective of this study was to understand how sleep duration could affect depression among elderly in China.

METHOD

A total of 7103 individuals aged 60 and older were selected from China Health and Retirement Longitudinal Study. A generalized linear mixed-effects model was used to estimate the relationship between sleep duration and depression, and we performed stratified analyses by age: young-old elderly, old-old elderly and oldest-old elderly.

RESULTS

Short sleep duration significantly incresased CES-D10 depression scores. In addition, the participants with middle sleep duration had higher CES-D10 scores compared to the participants with long sleep duration among young-old elderly, and we found that middle sleep duration was not significantly different from CES-D10 scores after adjustment for demographics, frequencies of activities and Chronic diseases.

CONCLUSIONS

These findings suggested that there was a complex association between depression and sleep duration among elderly in China. Different from previous research results on the middle or normal sleep time of the elderly, the middle sleep duration maybe not optimal sleep duration in this study. Investigation of sleep extension to prevent depression may be warranted among the elderly.

Sleep Disturbance and Self-management in Adults With Subarachnoid Hemorrhage: A Qualitative Study

Subarachnoid hemorrhage (SAH) survivors often experience sleep disturbances. Little is known about sleep-management practices used to improve their sleep. The purpose of this qualitative study was to explore interest in and engagement with self-management practices to promote sleep health in SAH survivors. We conducted a cross-sectional qualitative study using semi-structured interviews with a convenience sample of 30 SAH survivors recruited from a university hospital. We conducted content analysis of interview transcripts. Three themes and 15 subcategories were identified: (1) sleep disturbances (difficulties falling asleep, wake after sleep onset, daytime sleepiness, too much or insufficient sleep, and poor sleep quality); (2) sleep-management practices (exercise, regular sleep schedule, relaxation, keeping busy and staying active, changing beverage intake, taking supplements, taking medications, recharging energy, and barriers to sleep management); and (3) consulting with healthcare providers (discussing sleep problems with healthcare providers). Self-management strategies focusing on health-promoting behaviors may improve SAH survivors' sleep health.

Multimodal Exercise Effects in Older Adults Depend on Sleep, Movement Biography, and Habitual Physical Activity: A Randomized Controlled Trial

Background: The promotion of healthy aging is one of the major challenges for healthcare systems in current times. The present study investigates the effects of a standardized physical activity intervention for older adults on cognitive capacity, self-reported health, fear of falls, balance, leg strength and gait under consideration of movement biography, sleep duration, and current activity behavior. Methods: This single-blinded, randomized controlled trial included 49 community-dwelling older adults (36 women; 82.9 ± 4.5 years of age (Mean [M] ± SD); intervention group = 25; control group = 24). Movement biography, sleep duration, cognitive capacity, self-reported health status, and fear of falls were assessed by means of questionnaires. Leg strength, gait, and current activity levels were captured using a pressure plate, accelerometers, and conducting the functional-reach and chair-rising-test. The multicomponent intervention took place twice a week for 45 min and lasted 16 weeks. Sub-cohorts of different sleep duration were formed to distinguish between intervention effects and benefits of healthy sleep durations. Change scores were evaluated in univariate analyses of covariances (ANCOVAs) between groups and sub-cohorts of different sleep duration in both groups. Changes in cognitive capacity, self-reported health, fear of falls, balance, leg strength, and gait were investigated using the respective baseline values, movement biography, and current activity levels as covariates. Analysis was by intention-to-treat (ITT). Results: We found sub-cohort differences in cognitive capacity change scores [F _(3,48) = 5.498, p = 0.003, ηp ² = 0.287]. Effects on fear of falls [F _(1,48) = 12.961, p = 0.001, ηp ² = 0.240] and balance change scores F _(1,48) = 4.521, p = 0.040, ηp ² = (0.099) were modified by the level of current activity. Effects on gait cadence were modified by the movement biography [F _(1,48) = 4.545; p = 0.039, ηp ² = 0.100]. Conclusions: Unlike for functional outcomes, our multicomponent intervention in combination with adequate sleep duration appears to provide combinable beneficial effects for cognitive capacity in older adults. Trainability of gait, fear of falls, and flexibility seems to be affected by movement biography and current physical activity levels. Trial registration: This study was registered at the DRKS (German Clinical Trials Register) on November 11, 2020 with the corresponding trial number: DRKS00020472.

The association of sleep duration and metabolic syndrome in the Bandare-Kong cohort study, a cross-sectional survey (finding from PERSIAN cohort study)

BACKGROUND

A variety of health problems, such as metabolic syndrome (MetS), have been linked to sleep disorders. While numerous epidemiological studies have shown a U-shaped relationship between sleep duration and poor health outcomes, the results were limited and inconsistent. This study was designed to evaluate the relationship between sleep duration and MetS.

METHODS

This population-based study was conducted on the participants aged 35-70 of Bandare-Kong Non-Communicable Diseases (BKNCD) Cohort Study, a part of Prospective Epidemiological Research Studies in IrAN (PERSIAN). MetS was diagnosed according to the National Cholesterol Education Program (NCEP) criteria and the Iranian-specific cut-off for waist circumference (≥ 95 cm). Sleep information was extracted through a standard questionnaire based on self-reported information. Data were analyzed by R software using generalized additive models (GAMs). A statistically significant level was considered as P < 0.05.

RESULTS

A total of 3695 participants were included in the analyses. The mean age was 48.05 years (SD 9.36), and 2067 (55.9%) were female. The estimated Prevalence of MetS was 35.9%, and women appeared to be more likely to have MetS than men (P < 0.001). There was a non-linear and linear association between sleep duration and the risk of MetS in women and men, respectively. The lowest risk was observed among those with 7-7.5 h of sleep duration per night.

CONCLUSION

Long sleep duration was associated with increased risk of MetS and higher MetS severity score in both genders, while the short sleep duration increased the risk of Mets as well as MetS severity score just in women. The longitudinal studies would be suggested to assess the relationship between sleep quality and quantity components and MetS.

Understanding the Associations of Prenatal Androgen Exposure on Sleep Physiology, Circadian Proteins, Anthropometric Parameters, Hormonal Factors, Quality of Life, and Sex Among Healthy Young Adults: Protocol for an International, Multicenter Study

Background

The ratio of the second finger length to the fourth finger length (2D:4D ratio) is considered to be negatively correlated with prenatal androgen exposure (PAE) and positively correlated with prenatal estrogen. Coincidentally, various brain regions are sensitive to PAE, and their functions in adults may be influenced by the prenatal actions of sex hormones.

Objective

This study aims to assess the relationship between PAE (indicated by the 2D:4D ratio) and various physiological (sex hormone levels and sleep-wake parameters), psychological (mental health), and sexual parameters in healthy young adults.

Methods

This study consists of two phases. In phase 1, we will conduct a survey-based study and anthropometric assessments (including 2D:4D ratio and BMI) in healthy young adults. Using validated questionnaires, we will collect self-reported data on sleep quality, sexual function, sleep chronotype, anxiety, and depressive symptoms. In phase 2, a subsample of phase 1 will undergo polysomnography and physiological and genetic assessments. Sleep architecture data will be obtained using portable polysomnography. The levels of testosterone, estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, prolactin, melatonin, and circadian regulatory proteins (circadian locomotor output cycles kaput [CLOCK], timeless [TIM], and period [PER]) and the expression levels of some miRNAs will be measured using blood samples. The rest and activity cycle will be monitored using actigraphy for a 7-day period.

Results

In Poland, 720 participants were recruited for phase 1. Among these, 140 completed anthropometric measurements. In addition, 25 participants joined and completed phase 2 data collection. Recruitment from other sites will follow.

Conclusions

Findings from our study may help to better understand the plausible role of PAE in sleep physiology, mental health, and sexual quality of life in young adults.

International Registered Report Identifier (IRRID)

DERR1-10.2196/29199

Sleep duration, Health Promotion Index (HPI), sRAGE and ApoE-ε4 genotype are associated with telomere length (TL) in healthy elderly Australians

Significant alterations in sleep duration and/or quality of sleep become more pronounced as people get older. Poor sleep in elderly people is associated with adverse health outcomes and cellular ageing. We examined the relationship between TL and sleep duration, Health Promotion Index (HPI), and tested whether the presence of ApoE-ε4 allele impacts both sleep and TL. The present study was carried out in 174 healthy elderly subjects (21% male; mean age 53.79 years) from South Australia. Lymphocyte telomere length (TL) was measured by real-time qPCR and ApoE genotype was determined by TaqMan assay. HPI was calculated from a questionnaire regarding 8 lifestyle habits, including sleeping hours. Multivariate regression analysis was used to establish these associations adjusted for specified confounders. TL was found to be inversely associated with age (r = - 0.199; p = 0.008) and BMI (r = - 0.121; p = 0.11), and was significantly shorter in participants who slept for <7 hours (p = 0.001) relative to those sleeping ≥7 hours. TL was positively correlated with HPI (r = 0.195; p = 0.009). ApoE-ε4 allele carriers who slept for less than 7 hours had shortest TL (p = 0.01) compared to non-carriers. Plasma sRAGE level was significantly (p = 0.001) lower in individuals who sleep <7 hours and ApoE-ϵ4 carriers. Our results suggest that inadequate sleep duration or poor HPI is associated with shorter TL in cognitively normal elderly people and that carriage of APOE-ε4 genotype may influence the extent of these effects.

Association of Sleep Duration With All- and Major-Cause Mortality Among Adults in Japan, China, Singapore, and Korea

IMPORTANCE

The association between long sleep duration and mortality appears stronger in East Asian populations than in North American or European populations.

OBJECTIVES

To assess the sex-specific association between sleep duration and all-cause and major-cause mortality in a pooled longitudinal cohort and to stratify the association by age and body mass index.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study of individual-level data from 9 cohorts in the Asia Cohort Consortium was performed from January 1, 1984, to December 31, 2002. The final population included participants from Japan, China, Singapore, and Korea. Mean (SD) follow-up time was 14.0 (5.0) years for men and 13.4 (5.3) years for women. Data analysis was performed from August 1, 2018, to May 31, 2021.

EXPOSURES

Self-reported sleep duration, with 7 hours as the reference category.

MAIN OUTCOMES AND MEASURES

Mortality, including deaths from all causes, cardiovascular disease, cancer, and other causes. Sex-specific hazard ratios (HRs) and 95% CIs were estimated using Cox proportional hazards regression with shared frailty models adjusted for age and the key self-reported covariates of marital status, body mass index, smoking status, alcohol consumption, physical activity, history of diabetes and hypertension, and menopausal status (for women).

RESULTS

For 322 721 participants (mean [SD] age, 54.5 [9.2] years; 178 542 [55.3%] female), 19 419 deaths occurred among men (mean [SD] age of men, 53.6 [9.0] years) and 13 768 deaths among women (mean [SD] age of women, 55.3 [9.2] years). A sleep duration of 7 hours was the nadir for associations with all-cause, cardiovascular disease, and other-cause mortality in both men and women, whereas 8 hours was the mode sleep duration among men and the second most common sleep duration among women. The association between sleep duration and all-cause mortality was J-shaped for both men and women. The greatest association for all-cause mortality was with sleep durations of 10 hours or longer for both men (hazard ratio [HR], 1.34; 95% CI, 1.26-1.44) and women (HR, 1.48; 95% CI, 1.36-1.61). Sex was a significant modifier of the association between sleep duration and mortality from cardiovascular disease (χ25 = 13.47, P = .02), cancer (χ25 = 16.04, P = .007), and other causes (χ25 = 12.79, P = .03). Age was a significant modifier of the associations among men only (all-cause mortality: χ25 = 41.49, P < .001; cancer: χ25 = 27.94, P < .001; other-cause mortality: χ25 = 24.51, P < .001).

CONCLUSIONS AND RELEVANCE

The findings of this cohort study suggest that sleep duration is a behavioral risk factor for mortality in both men and women. Age was a modifier of the association between sleep duration in men but not in women. Sleep duration recommendations in these populations may need to be considered in the context of sex and age.

Gender differences in self-reported sleep problems among older adults in six middle-income countries: a cross-sectional study

This study examines gender differences in sleep problems among older adults in India, China, Ghana, Mexico, Russia, and South Africa. We used data on 33,929 individuals (50+ years) from the WHO-SAGE. Results showed significant gender differences in the prevalence of sleep problems with the largest difference in Russia followed by India. Regression results showed higher odds of sleep problems among women in India, China, Russia, and South Africa. Age, low back pain, depression, and poor self-rated health were significantly associated with sleep problems. This research confirms significant gender differences in sleep problems among the older population in middle-income countries.

Association of objectively measured sleep with frailty and 5-year mortality in community-dwelling older adults

STUDY OBJECTIVES

To determine whether actigraphy-measured sleep was independently associated with risk of frailty and mortality over a 5-year period among older adults.

METHODS

We used data from Waves 2 (W2) and 3 (W3) (2010-2015) of the National Social Life, Health and Aging Project, a prospective cohort of community-dwelling older adults born between 1920 and 1947. One-third of W2 respondents were randomly selected to participate in a sleep study, of whom N = 727 consented and N = 615 were included in the analytic sample. Participants were instructed to wear a wrist actigraph for 72 h (2.93 ± 0.01 nights). Actigraphic sleep parameters were averaged across nights and included total sleep time, percent sleep, sleep fragmentation index, and wake after sleep onset. Subjective sleep was collected via questionnaire. Frailty was assessed using modified Fried Frailty Index. Vital status was ascertained at the time of the W3 interview. W3 frailty/mortality status was analyzed jointly with a four-level variable: robust, pre-frail, frail, and deceased. Associations were modeled per 10-unit increase.

RESULTS

After controlling for baseline frailty (robust and pre-frail categories), age, sex, education, body mass index, and sleep time preference, a higher sleep fragmentation index was associated with frailty (OR = 1.70, 95% CI: 1.02-2.84) and mortality (OR = 2.12, 95% CI: 1.09-4.09). Greater wake after sleep onset (OR = 1.24, 95% CI: 1.02-1.50) and lower percent sleep (OR = 0.41, 95% CI: 0.17-0.97) were associated with mortality.

CONCLUSIONS

Among community-dwelling older adults, actigraphic sleep is associated with frailty and all-cause mortality over a 5-year period. Further investigation is warranted to elucidate the physiological mechanisms underlying these associations.

Habitual Physical Activity and Sleep Duration in Institutionalized Older Adults

Background: Physical activity and sleep quality are both major factors for improving one's health. Knowledge on the interactions of sleep quality and the amount of physical activity may be helpful for implementing multimodal health interventions in older adults.

Methods: This preliminary cross-sectional study is based on 64 participants [82.1 ± 6.4 years (MD ± SD); 22 male: 42 female]. The amount of physical activity was assessed by means of an accelerometer (MyWellness Key). Self-reported sleep parameters were obtained using the Pittsburgh Sleep Quality Index. The Barthel Index was used for physical disability rating. Bivariate correlations (Spearman's Rho) were used to explore relationships between the amount of physical activity and sleep quality. To analyse differences between categorial subgroups univariate ANOVAs were applied; in cases of significance, these were followed by Tukey-HSD post-hoc analyses.

Results: No linear association between physical activity and sleep quality was found (r = 0.119; p > 0.05). In subgroup analyses (n = 41, Barthel Index ≥90 pts, free of pre-existing conditions), physical activity levels differed significantly between groups of different sleep duration (≥7 h; ≥6 to <7 h; ≥5 to <6 h; <5h; p = 0.037).

Conclusion: There is no general association between higher activity levels and better sleep quality in the investigated cohort. However, a sleep duration of ≥5 to <6 h, corresponding to 7.6 h bed rest time, was associated with a higher level of physical activity.

Sleep Characteristics and Hearing Loss in Older Adults: The National Health and Nutrition Examination Survey 2005-2006

BACKGROUND

Sleep characteristics might be associated with hearing loss through disturbed energy metabolism and disrupted cochlear blood flow, but prior evidence is limited. This study aims to investigate cross-sectional associations of sleep duration and signs/symptoms of sleep-disordered breathing with hearing in a nationally representative cohort of U.S. older adults aged 70 and over.

METHODS

We studied 632 older adults aged 70+ years from the 2005-2006 cycle of National Health and Nutrition Examination Survey (NHANES). Hearing thresholds were measured using pure-tone audiometry and were averaged to create speech-frequency (0.5-4 kHz), low-frequency (0.5-2 kHz) and high-frequency (4-8 kHz) pure-tone averages (PTAs) in better-hearing ear, with higher values indicate worse hearing. Sleep duration and signs/symptoms of sleep-disordered breathing (snoring, snorting/stopping breathing, excessive sleepiness) were collected through questionnaire. Multivariable-adjusted spline models with knots at 6 and 8 hours were fitted for associations between sleep duration and PTAs. Multivariable-adjusted linear regression was used for associations between sleep-disordered breathing and PTAs. Primary models adjusted for demographic and lifestyle factors, secondary models additionally adjusted for cardiovascular factors.

RESULTS

When sleep duration exceeded 8 hours, every additional hour of sleep duration was marginally associated with higher(poorer) high-frequency PTA (Primary:2.45 dB HL, 95% CI:-0.34, 5.24; Secondary:2.89 dB HL, 95% CI:0.02, 5.76). No associations were observed between sleep-disordered breathing and hearing.

CONCLUSIONS

Longer sleep duration is marginally associated with poorer high-frequency hearing among older adults sleeping more than 8 hours. However, we cannot infer temporality given the cross-sectional design. Future longitudinal studies are needed to establish temporality and clarify mechanisms.

Sleep duration, vegetable consumption and all-cause mortality among older adults in China: a 6-year prospective study

BACKGROUND

Sleep duration and vegetable consumption are associated with mortality at old age (termed as sleep-mortality linkage and vegetable-mortality linkage, respectively). Yet, little is known about the interplay of sleep duration and vegetable consumption on mortality.

METHODS

A dataset of nationwide longitudinal survey with 13,441 participants aged 65 years or older recruited in 2008 and followed up till 2014 was used. Sleep duration was classified into five groups (≤5, 6, 7-8, 9, and ≥ 10 h/day). Vegetable consumption was classified as either high frequency (eating vegetables almost daily) or low frequency. We used parametric Weibull hazard regression models to estimate associations of sleep duration and frequency of vegetable consumption with mortality, adjusting for demographics, socioeconomic factors, family/social support, health practice, and health conditions.

RESULTS

Over the six-year study period, when only demographics were present, participants sleeping ≤5, 6, 9, and ≥ 10 h/day had relative hazard (RH) of mortality 1.18 (p < 0.001), 1.14(p < 0.01), 1.06 (p > 0.1), and 1.30 (p < 0.001), respectively, compared to those sleeping 7-8 h/day. The HRs were attenuated to 1.08 (p < 0.05), 1.08 (p < 0.05), 1.09 (p < 0.1), 1.18(p < 0.001), respectively, when all other covariates were additionally adjusted for. High frequency of eating vegetables was associated with 22% lower risk of mortality (RH= 0.78, p < 0.001) compared to low frequency in the demographic model, and with 9% lower risk (RH = 0.91, p < 0.05) in the full model. Subpopulation and interaction analyses show that the sleeping-mortality linkage was stronger in female, urban, oldest-old (aged ≥80), and illiterate participants compared to their respective male, rural, young-old, and literate counterparts. High frequency of vegetable intakes could offset the higher mortality risk in participants with short-sleeping duration, but low frequency of eating vegetables could exacerbate mortality risk for participants with either short or long sleep duration; and except for few cases, these findings held in subpopulations.

CONCLUSIONS

Too short and too long sleep durations were associated with higher mortality risk, and infrequent vegetable consumption could exacerbate the risk, although frequent vegetable intake could offset the risk for short sleep duration. The relationship between these two lifestyles and mortality was complex and varied among subpopulations.

Association of Rapid Eye Movement Sleep With Mortality in Middle-aged and Older Adults

Importance

Rapid eye movement (REM) sleep has been linked with health outcomes, but little is known about the relationship between REM sleep and mortality.

Objective

To investigate whether REM sleep is associated with greater risk of mortality in 2 independent cohorts and to explore whether another sleep stage could be driving the findings.

Design, Setting, and Participants

This multicenter population-based cross-sectional study used data from the Outcomes of Sleep Disorders in Older Men (MrOS) Sleep Study and Wisconsin Sleep Cohort (WSC). MrOS participants were recruited from December 2003 to March 2005, and WSC began in 1988. MrOS and WSC participants who had REM sleep and mortality data were included. Analysis began May 2018 and ended December 2019.

Main Outcomes and Measures

All-cause and cause-specific mortality confirmed with death certificates.

Results

The MrOS cohort included 2675 individuals (2675 men [100%]; mean [SD] age, 76.3 [5.5] years) and was followed up for a median (interquartile range) of 12.1 (7.8-13.2) years. The WSC cohort included 1386 individuals (753 men [54.3%]; mean [SD] age, 51.5 [8.5] years) and was followed up for a median (interquartile range) of 20.8 (17.9-22.4) years. MrOS participants had a 13% higher mortality rate for every 5% reduction in REM sleep (percentage REM sleep SD = 6.6%) after adjusting for multiple demographic, sleep, and health covariates (age-adjusted hazard ratio, 1.12; fully adjusted hazard ratio, 1.13; 95% CI, 1.08-1.19). Results were similar for cardiovascular and other causes of death. Possible threshold effects were seen on the Kaplan-Meier curves, particularly for cancer; individuals with less than 15% REM sleep had a higher mortality rate compared with individuals with 15% or more for each mortality outcome with odds ratios ranging from 1.20 to 1.35. Findings were replicated in the WSC cohort despite younger age, inclusion of women, and longer follow-up (hazard ratio, 1.17; 95% CI, 1.03-1.34). A random forest model identified REM sleep as the most important sleep stage associated with survival.

Conclusions and Relevance

Decreased percentage REM sleep was associated with greater risk of all-cause, cardiovascular, and other noncancer-related mortality in 2 independent cohorts.

The Relationship Between Diet and Sleep in Older Adults: a Narrative Review

PURPOSE OF REVIEW

Older adults more frequently experience reduced sleep quality and quantity compared to younger adults. Diet is one modifiable lifestyle factor that may influence sleep outcomes in older adults. The purpose of this review is to synthesise the current literature investigating the impact of diet, including foods and nutrients, on the sleep quality and quantity of older adults.

RECENT FINDINGS

Overall, the observational and intervention studies suggest that following a Mediterranean diet, and the consumption of certain food items (e.g. milk), and nutrients (e.g. vitamin D and vitamin E) may influence (improve or reduce) sleep quality and quantity. This review describes the potential efficacy for dietary factors to improve sleep outcomes in older adults. However, given the heterogeneity of included studies in this review (i.e. aims, methodologies, and outcomes assessed), it is difficult to consolidate the available evidence to make specific recommendations. More targeted research exploring the relationship between diet and sleep in older adults is needed to strengthen the current evidence base.

Are periodontal diseases associated with sleep duration or sleep quality? A systematic review

OBJECTIVES

This study aimed to systematically review the associations between periodontal diseases/tooth loss and sleep duration/quality.

MATERIAL AND METHODS

PubMed, Scopus, and Embase databases were searched (up to May 2021) to identify studies that assessed the association between periodontal diseases or number of teeth with sleep quality and sleep duration. Two researchers independently selected the studies and extracted the data. Considering the high heterogeneity among the included studies, meta-analysis was deemed unviable. Results are presented descriptively for sleep quality (studies that have used PSQI), self-reported sleep hours, and other tools that assessed sleep patterns.

RESULTS

Twenty studies (16 cross-sectional, two case-control, and two cohort) were included. Eight studies used the Pittsburgh Sleep Quality Index (PSQI) to assess quality of sleep. Six of these studies demonstrated that individuals with worse periodontal conditions demonstrated poorer sleep quality. However, most of the included studies that performed adjusted analysis showed no statistically significant association between self-reported hours of sleep and periodontitis. The mean number of present teeth was assessed in four studies; three of them demonstrated lower numbers of present teeth in individuals with inadequate sleep.

CONCLUSION

The literature shows conflicting results for the association between sleep hours and periodontitis. However, inadequate sleep may be associated with lower number of present teeth and periodontal diseases. Further studies are necessary in order to confirm these results.

Daily variation in sleep characteristics in individuals with and without post traumatic stress disorder

BACKGROUND

Sleep disturbances are common in individuals with post traumatic stress disorder (PTSD). However, little is known about how daily variation in sleep characteristics is related to PTSD. This study examined the night-to-night and weekday versus weekend variation in sleep duration, sleep quality, trouble falling asleep, and difficulty staying asleep in individuals with and without PTSD.

METHODS

Participants (N = 157; 80 with PTSD, 77 without PTSD) completed daily self-reports of their nighttime sleep characteristics for 15 consecutive days. Linear mixed models were used to examine the associations between the 7 days of the week and weekday versus weekend variation in sleep characteristics and PTSD.

RESULTS

Individuals with PTSD reported shorter sleep duration, lower sleep quality, more trouble falling asleep, and more difficulty staying asleep than individuals without PTSD. The pattern of change across the week and between weekdays and weekends was different between those with and without PTSD for sleep quality and trouble falling asleep. Among those with PTSD, sleep duration, sleep quality, and trouble falling asleep differed across the 7 days of the week and showed differences between weekdays and weekends. For those without PTSD, only sleep duration differed across the 7 days of the week and showed differences between weekdays and weekends. Neither group showed 7 days of the week nor weekday versus weekend differences in difficulty staying asleep.

CONCLUSIONS

On average those with PTSD had shorter sleep duration, poorer sleep quality, and greater trouble falling and staying asleep. In particular, the day of week variation in sleep quality and trouble falling asleep specifically distinguishes those with PTSD from those without PTSD. Our findings suggest that clinical care might be improved by assessments of sleep patterns and disturbances across at least a week, including weekdays and weekends. Future studies should explore the mechanisms related to the patterns of sleep disturbance among those with PTSD.

Family aggregation of sleep characteristics: Results of the Heinz Nixdorf Recall and the Multi-Generation Study

INTRODUCTION

Poor sleep is a risk factor for adverse health events. For health prevention, it may be helpful to know whether poor sleep or sleep disorders in individuals are associated with sleep problems in their partners or children.

METHODS

In the MultiGeneration Study (MGS, conducted from 2013 to 2016), 1237 partners (aged 27 to 90 years) and 1660 adult children (aged 18 to 66 years) of index persons were recruited. Index persons are participants of the Heinz Nixdorf Recall Study, a population-based cohort study in the Ruhr area (study start 1999-2001, 4841 participants aged 45-75 years). We used two analysis populations: one with 1181 index persons whose partners were in MGS, and one with 1083 index persons with at least one adult child in MGS. Sleep characteristics were assessed using questionnaires (including the Pittsburgh Sleep Quality Index). The exposure was the presence of a sleep characteristic of the index subject.

RESULTS

Children showed the investigated sleep characteristics more often if these were also present in their parent (e.g., RR (relative risk) = 1.28 (95% CI: 1.06-1.55) for poor sleep quality). In partners, strong associations were observed for rising times and napping, but only weak associations for snoring, poor sleep quality and sleep disorders. Snoring of the bed partner is a risk factor for poor sleep (e.g., RR = 1.67 (0.91-3.07) for difficulties falling asleep).

CONCLUSION

Aggregation is observed for many sleep characteristics in people living in partnerships as well as in parents and their adult children.