Potential biochemical pathways for the relationship between sleep duration and mortality

Poor sleep quality increases mortality risk: A population-based longitudinal prospective study in community-dwelling middle-aged and older adults

OBJECTIVES

To assess the association between sleep quality and all-cause mortality in community-dwelling adults living in rural Ecuador.

METHODS

Individuals aged ≥40years enrolled in the prospective population-based Three Villages Study cohort were included. Sleep quality was assessed by means of the Pittsburgh Sleep Quality Index. Study participants were evaluated at baseline and at every annual door-to-door survey until they remained enrolled in the study. Mixed models Poisson regression for repeated Pittsburgh Sleep Quality Index determinations and multivariate Cox-proportional hazards models were fitted to estimate mortality risk according to sleep quality.

RESULTS

Analysis included 1494 individuals (mean age: 56.6 ± 12.5years; 56% women) followed for a median of 6.3 ± 3.3years. At baseline, 978 (65%) individuals had good sleep quality and 516 (35%) had poor sleep quality. The effects of Pittsburgh Sleep Quality Index scores changing over time on mortality was confounded by the impact of the SARS-CoV-2 pandemic on both. One hundred ninety-five individuals (13%) died during the follow-up, resulting in a crude mortality rate of 1.58 per 100 person years (95% C.I.: 1.27-1.88) for individuals with good sleep quality, and 3.18 (95% C.I.: 2.53-3.82) for those with poor sleep quality at baseline. A multivariate Cox-proportional hazards model showed that individuals with poor sleep quality at baseline were 1.38 times (95% C.I.: 1.02-1.85) more likely to die compared to those with good sleep quality; in this model, increased age, poor physical activity, and high fasting glucose remained significant.

CONCLUSIONS

Poor sleep quality is associated with increased mortality risk among middle-aged and older adults.

Actigraphic sleep monitoring in patients with post-traumatic stress disorder (PTSD): A meta-analysis

OBJECTIVE

Sleep disruption is a common complaint among patients with post-traumatic stress disorder (PTSD). Modern technology of activity monitoring (actigraphy) enables extended, objective, unobtrusive recording and measuring of daytime and nighttime activity. We conducted a meta-analysis to investigate the actigraphic sleep patterns in PTSD compared with healthy controls.

METHODS

We searched through seven electronic databases from inception to July 2022. Only case-control studies comparing rest-activity variables measured by actigraphy devices between clinically diagnosed PTSD patients and healthy individuals were included.

RESULTS

We identified 12 eligible studies comparing 323 PTSD patients and 416 healthy controls. Using a random-effects model, we showed that PTSD patients have significantly lower sleep efficiency (SMD: -0.26, 95 % CI = -0.51 to -0.004, p < .05, I² = 29.31 %), more fragmented sleep (SMD: 0.52, 95 % CI = 0.17 to 0.87, p < .01, I² = 0 %), and longer time in bed (SMD: 0.41, 95 % CI = 0.07 to 0.74, p < .05, I² = 0 %) compared to healthy controls.

LIMITATIONS

This study included a limited number of studies. Publication bias was not examined on all variables, which could lead to an overestimation of effect size. Four studies involved veterans, which likely differ from civilians regarding traumatic exposure.

CONCLUSION

This meta-analytic review highlighted a pattern of sleep disturbances in PTSD patients compared with non-PTSD individuals. High-quality, large-scale studies are necessary to draw a definitive conclusion regarding the distinctive sleep profile in PTSD. Future research can pay attention to sleep-specific mechanisms underlying PTSD and explore the momentary interactions between sleep-wake variables.

Sleep duration and risk of cardio-cerebrovascular disease: A dose-response meta-analysis of cohort studies comprising 3.8 million participants

Background

The effect of extreme sleep duration on the risk of cardiovascular and cerebrovascular diseases (CCDs) remains debatable. The pathology of CCDs is consistent in some respects (e.g., vascular factors), suggesting that there may be an overlapping range of sleep duration associated with a low risk of both diseases We aimed to quantify the dose-response relationship between sleep duration and CCDs.

Study objective

To explore whether there is an optimal sleep duration (SD) in reducing the risk of CCDs.

Methods

PubMed and EMBASE were searched until June 24, 2022 to include cohort studies that investigated the longitudinal relationships of SD with incident CCDs, including stroke and coronary heart disease (CHD). The robusterror meta-regression model (REMR model) was conducted to depict the dose-response relationships based on multivariate-adjusted risk estimates.

Results

A total of 71 cohorts with 3.8 million participants were included for meta-analysis, including 57 for cardiovascular diseases (CVD) and 29 for cerebrovascular disease. A significant U-shaped relationship was revealed of nighttime sleep duration with either cardiovascular or cerebrovascular disease. The nighttime sleep duration associated with a lower risk of CVD was situated within 4.3–10.3 h, with the risk hitting bottom at roughly 7.5 h per night (pnon–linearity &lt; 0.0001). Sleep duration associated with a lower risk of cerebrovascular diseases ranges from 5 to 9.7 h per night, with the inflection at 7.5 h per night (pnon–linearity = 0.05). Similar non-linear relationship exited in daily sleep duration and CCDs. Other subgroup analyses showed non-linear relationships close to the above results.

Conclusion

Rational sleep duration (7.5 h/night) is associated with a reduced risk of cardio-cerebrovascular disease for adults.

The Association Between Habitual Sleep Duration and Mortality According to Sex and Age: The Japan Public Health Center-based Prospective Study

BACKGROUND

Short and long sleep durations are associated with mortality outcomes. The association between sleep duration and mortality outcomes may differ according to sex and age.

METHODS

Participants of the Japan Public Health Center-based prospective study (JPHC Study) were aged 40-69 years and had completed a detailed questionnaire on lifestyle factors. Sex- and age-stratified analyses on the association between habitual sleep duration and mortality from all-causes, cardiovascular diseases (CVD), cancer and other causes included 46,152 men and 53,708 women without a history of CVD or cancer. Cox proportional hazards regression models, adjusted for potential confounders, were used to determine hazard ratios and 95% confidence intervals.

RESULTS

Mean follow-up time was 19.9 years for men and 21.0 years for women. In the multivariable sex-stratified models, some categories of sleep durations ≥8 hours were positively associated with mortality from all-causes, CVD, and other causes in men and women compared with 7 hours. The sex- and age-stratified analyses did not reveal any major differences in the association between sleep duration and mortality outcomes in groups younger and older than 50 years of age. The only exception was the significant interaction between sleep duration and age in women for mortality from other causes.

CONCLUSIONS

Sleep durations ≥8 hours are associated with mortality outcomes in men and women. Age may be an effect modifier for the association between sleep duration and mortality from other causes in women.

Sleep duration and risk of all-cause mortality: a systematic review and meta-analysis

AIMS

To determine the association between the sleep duration and the risk of all-cause mortality in adults.

METHODS

A search strategy was conducted in the MEDLINE, CENTRAL, EMBASE and LILACS databases. Searches were also conducted in other databases and unpublished literature. Cohort studies were included without language, time or setting restrictions. The risk of bias was evaluated with a modified Cochrane Collaboration's tool. An analysis of random effects was conducted. The primary outcome was all-cause mortality. The measure of the effect was the risk difference (RD) with a 95% confidence interval (CI). The planned comparisons were 7-9 h of sleep v. <7 h and the same reference v. >9 h.

RESULTS

Thirty-nine studies were included in our qualitative analysis, regarding the quantitative analysis, 19 studies were included in <7 v. 7-9 h analysis, and 18 studies in the >9 v. 7-9 h. A low risk of bias was shown for most of the study items. The overall RD for all-cause mortality was 0.09 (95% CI 0.07-0.11) favouring the >9 h group compared with our reference. In contrast, no differences were found between the <7 h and the reference sleep duration groups (RD 0.00, 95% CI 0.00-0.01).

CONCLUSION

We found a probable association of long sleep duration and higher mortality; however, it could reflect an underlying systemic or neurological disease that cause sleep fragmentation, deterioration in quality and micro-awakenings.

Association of Obesity and Frailty in Older Adults: NHANES 1999-2004

OBJECTIVES

Body composition changes with aging can increase rates of obesity, frailty and impact function. Measuring adiposity using body fat (%BF) or central adiposity using waist circumference (WC) have greater diagnostic accuracy than traditional measures such as body mass index (BMI).

DESIGN

This is an observational study.

SETTING

This study focused on older community-dwelling participants.

PARTICIPANTS

We identified individuals age ≥ 60 years old using the 1999-2004 cross-sectional National Health and Nutrition Survey (NHANES).

INTERVENTION

The primary analysis evaluated the association between frailty and %BF or WC. Frailty was the primary predictor (robust=referent) and %BF and WC were considered continuous outcomes. Multiple imputation analyses accounted for missing characteristics.

MEASUREMENT

Dual energy x-ray absorptiometry was used to assess %BF and WC was objectively measured. Frailty was defined using an adapted version of Fried's criteria that was self-reported: (low BMI<18.5kg/m2; slow walking speed [<0.8m/s]; weakness [unable to lift 10lbs]; exhaustion [difficulty walking between rooms on same floor] and low physical activity [compared to others]). Robust, pre-frail and frail persons met zero, 1 or 2, and ≥3 criteria, respectively.

RESULTS

Of the 4,984 participants, the mean age was 71.1±0.2 (SE) years and 56.5% were females. We classified 2,246 (50.4%), 2,195 (40.3%), and 541 (9.2%) individuals as robust, pre-frail and frail, respectively. Percent BF was 35.9±0.13, 38.3±0.20 and 40.0±0.46 in the robust, pre-frail and frail individuals, respectively. WC was 99.5±0.32 in the robust, 100.1±0.43 in pre-frail, 104.7±1.17 in frail individuals. Compared to robust individuals, only frail individuals had greater %BF on average (β=0.97±0.43,p=0.03); however, pre-frail and frail individuals had 2.18 and 4.80 greater WC, respectively (β=2.18±0.64,p=0.002, and β=4.80±1.1,p<0.001).

CONCLUSION

Our results demonstrate that in older adults, frailty and pre-frailty are associated with a greater likelihood of high WC (as dichotomized) and a greater average WC (continuous).

Sleep Latency in Men and Sleep Duration in Women Can Be Frailty Markers in Community-Dwelling Older Adults: The Korean Frailty and Aging Cohort Study (KFACS)

OBJECTIVES

To test whether sleep disturbances are associated with frailty in older men and women.

DESIGN

Cross-sectional analysis of cohort study data. The participants were 1168 community-dwelling older adults aged 70 to 84 years who took part in the Korean Frailty and Aging Cohort Study and completed both self-reported sleep parameters and assessment of frailty. Univariate and multivariate survey logistic regression models were used to calculate odds ratios (OR) with 95% confidence intervals (CI) for frailty. Frailty was defined using the Fried's criteria.

RESULTS

Frailty was associated with sleep latency in men. The odds ratio for this association was 3.39 (95% CI 1.31-8.76) after adjusting for age, body mass index (BMI), physical activity, and select comorbidities, and 2.16 (95% CI 0.75-6.23) after further adjusting for depression. Frailty was associated with long sleep duration of more than 8 hours a night in women. The odds ratio for this association was 3.95 (95% CI, 1.27-12.33) after adjusting for age, BMI, physical activity, select comorbidities, and the number of medications.

CONCLUSION

Prolonged sleep latency (≥60 minutes) in men and long sleep duration (>8hr per night) in women were each independently associated with higher odds of frailty. Long sleep latency in elderly men and long sleep duration in elderly women may suggest they have a high chance of frailty.

Self-Reported Sleep Duration and Quality and Cardiovascular Disease and Mortality: A Dose-Response Meta-Analysis

Background There is growing evidence that sleep duration and quality may be associated with cardiovascular harm and mortality. Methods and Results We conducted a systematic review, meta-analysis, and spline analysis of prospective cohort studies that evaluate the association between sleep duration and quality and cardiovascular outcomes. We searched MEDLINE and EMBASE for these studies and extracted data from identified studies. We utilized linear and nonlinear dose-response meta-analysis models and used DerSimonian-Laird random-effects meta-analysis models of risk ratios, with inverse variance weighting, and the I2 statistic to quantify heterogeneity. Seventy-four studies including 3 340 684 participants with 242 240 deaths among 2 564 029 participants who reported death events were reviewed. Findings were broadly similar across both linear and nonlinear dose-response models in 30 studies with >1 000 000 participants, and we report results from the linear model. Self-reported duration of sleep >8 hours was associated with a moderate increased risk of all-cause mortality, with risk ratio , 1.14 (1.05-1.25) for 9 hours, risk ratio, 1.30 (1.19-1.42) for 10 hours, and risk ratio, 1.47 (1.33-1.64) for 11 hours. No significant difference was identified for periods of self-reported sleep <7 hours, whereas similar patterns were observed for stroke and cardiovascular disease mortality. Subjective poor sleep quality was associated with coronary heart disease (risk ratio , 1.44; 95% confidence interval, 1.09-1.90), but no difference in mortality and other outcomes. Conclusions Divergence from the recommended 7 to 8 hours of sleep is associated with a higher risk of mortality and cardiovascular events. Longer duration of sleep may be more associated with adverse outcomes compared with shorter sleep durations.

The association of major patterns of physical activity, sedentary behavior and sleeping with mortality in older adults

Objective: To identify major patterns of physical activity (PA), sedentary behavior (SB) and sleeping (all self-reported), and their association with long-term mortality. Methods: Cohort of 2,851 individuals aged ≥ 60 from Spain. Mortality was ascertain from 2003 up to July 2013. Patterns of PA, SB and sleeping were identified by factor analysis. Results: During follow-up, 1,145 deaths occurred. The first pattern, named "sedentary and non-active pattern", was characterized by long sleeping or lying time, and not doing even light PA (household chores or walking). The second pattern was named "active and non-sedentary pattern", and was characterized long time devoted to vigorous activities, long walking time, and short seating time. Compared to those in the first quartile of the "sedentary and non-active pattern", those in the highest quartile showed a 71% higher mortality (HR: 1.71; 95%CI: 1.42-2.07; p-trend:<0.001); it corresponds to being 6-year older. By contrast, being in the highest versus the lowest quartile of the "active and non-sedentary pattern" was associated with a 32% lower mortality (HR: 0.68: 0.57-0.82; p-trend:<0.001); it corresponds to being 4-year younger. Conclusion: The "sedentary and non-active" pattern had a large impact on mortality. The "active and non-sedentary" pattern showed an opposite and slightly lower association.

The association of sleep duration and quality with all-cause and cause-specific mortality in the Women's Health Initiative

BACKGROUND/OBJECTIVE

Many studies have shown a U-shaped association of sleep duration with mortality; however, this association is difficult to interpret owing to possible reverse causation, residual confounding, and measurement issues. We used data from the Women's Health Initiative to examine the associations of sleep duration, insomnia, and use of sleep aids with death from cardiovascular disease (CVD), cancer, "other" causes, and all causes combined.

METHODS

Cox proportional hazards models were used in the analysis of baseline data and in time-dependent analyses of repeated measures to estimate associations of sleep-related factors with mortality. Among 158,203 women with information regarding sleep, 30,400 total deaths, 8857 CVD deaths, 9284 cancer deaths, and 11,928 other deaths were ascertained over a median of 17.8 years.

RESULTS

In both baseline and time-dependent analyses, both short (≤5 h) and long sleep (≥9 h) durations were associated with increased risk of total, CVD, and "other" deaths, but not with cancer deaths. Insomnia showed no association with mortality, whereas use of sleep medications was associated with an increased mortality risk.

CONCLUSIONS

While our findings showed a small but robust association of sleep duration with mortality in postmenopausal women, studies including objective measurements of sleep quality and efficiency are needed to clarify these associations.

Sleep Duration Interacts With Lifestyle Risk Factors and Health Status to Alter Risk of All-Cause Mortality: The Rural Chinese Cohort Study

STUDY OBJECTIVES

Many studies suggest an association of both short and long sleep duration with all-cause mortality, but the effect of co-occurrence of sleep duration and other lifestyle risk factors or health status remains unclear.

METHODS

A total of 17,184 participants aged 18 years or older from rural areas of China were examined at baseline from 2007 to 2008 and followed up from 2013 to 2014. Cox proportional hazard models were used to estimate the hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

During 6-year follow-up, we identified 1,101 deaths. The multivariable-adjusted mortality risk was significantly higher with short-duration sleepers (< 6.5 hours) (HR = 1.37, 95% CI 1.01-1.86) and long-duration sleepers (≥ 9.5 hours) (HR = 1.35, 95% CI 1.05-1.74) versus 6.5-7.5 hours. The multiplicative interaction of long sleep duration with some lifestyle risk factors and health statuses increased the mortality risk in men (low level of physical activity: HR = 1.03, 95% CI 1.02-1.04; hypertension: HR = 1.06, 95% CI 1.04-1.09; type 2 diabetes mellitus [T2DM]: HR = 1.07, 95% CI 1.04-1.11). Similar results were found in women (low level of physical activity: HR = 1.03, 95% CI 1.02-1.05; T2DM: HR = 1.07, 95% CI 1.05-1.10).

CONCLUSIONS

Sleep duration could be a predictor of all-cause mortality and its interaction with physical activity, hypertension, and T2DM may increase the risk of mortality.

Long and Short Sleep Duration and Physical Frailty in Community-Dwelling Older Adults

OBJECTIVE

The objective of this study was to investigate whether older adults who have a particularly long sleep duration are likely to exhibit physical frailty, similar to those with a particularly short sleep duration.

DESIGN

Cross-sectional study.

SETTING

The National Center for Geriatrics and Gerontology - Study of Geriatric Syndromes.

PARTICIPANTS

A total of 9,824 older adults (mean age: 73.6 ± 5.5 years, 4,812 men and 5,012 women) met the entry criteria for this study.

MEASUREMENTS

We divided the participants into three groups according to self-reported sleep duration (Short: ≤6 h, Mid: 6.1-8.9 h (control), Long: ≥ 9 h). Physical frailty was characterized based on the criteria from the Cardiovascular Health Study. Multinomial logistic regression analysis was performed to evaluate the effect of sleep duration on physical frailty by sex.

RESULTS

Among all participants, the prevalence of physical frailty was higher in the Short (10.5%) and Long (17.9%) groups than in the Mid (7.4%) group (p < 0.001). Multinomial logistic regression analysis showed that both Short and Long groups had a significantly higher odds ratio (OR) for physical frailty than the Mid group [Short: OR 1.53, 95% confidence interval (CI) 1.26-1.87; Long: OR 2.39, 95% CI 1.90-3.00], even after adjusting for age, educational level, number of medications, body mass index, Mini Mental State Examination score, current smoking and alcohol habits, self-perceived health, and medical history.

CONCLUSION

Both long and short sleep durations were associated with physical frailty. Further studies are required to confirm the effect of sleep duration on the incidence or worsening of physical frailty in older adults.

Relationship of Sleep Duration With All-Cause Mortality and Cardiovascular Events: A Systematic Review and Dose-Response Meta-Analysis of Prospective Cohort Studies

Background

Effects of extreme sleep duration on risk of mortality and cardiovascular outcomes remain controversial. We aimed to quantify the dose‐response relationships of sleep duration with risk of all‐cause mortality, total cardiovascular disease, coronary heart disease, and stroke.

Methods and Results

PubMed and Embase were systematically searched for prospective cohort studies published before December 1, 2016, that examined the associations between sleep duration and at least 1 of the 4 outcomes in generally healthy populations. U‐shaped associations were indicated between sleep duration and risk of all outcomes, with the lowest risk observed for ≈7‐hour sleep duration per day, which was varied little by sex. For all‐cause mortality, when sleep duration was <7 hours per day, the pooled relative risk (RR) was 1.06 (95% CI, 1.04–1.07) per 1‐hour reduction; when sleep duration was >7 hours per day, the pooled RR was 1.13 (95% CI, 1.11–1.15) per 1‐hour increment. For total cardiovascular disease, the pooled RR was 1.06 (95% CI, 1.03–1.08) per 1‐hour reduction and 1.12 (95% CI, 1.08–1.16) per 1‐hour increment of sleep duration. For coronary heart disease, the pooled RR was 1.07 (95% CI, 1.03–1.12) per 1‐hour reduction and 1.05 (95% CI, 1.00–1.10) per 1‐hour increment of sleep duration. For stroke, the pooled RR was 1.05 (95% CI, 1.01–1.09) per 1‐hour reduction and 1.18 (95% CI, 1.14–1.21) per 1‐hour increment of sleep duration.

Conclusions

Our findings indicate that both short and long sleep duration is associated with an increased risk of all‐cause mortality and cardiovascular events.

Long sleep duration and health outcomes: A systematic review, meta-analysis and meta-regression

We examined the dose-response relationship between long sleep duration and health outcomes including mortality and the incidence of diabetes mellitus, hypertension, cardiovascular diseases, stroke, coronary heart diseases, obesity, depression and dyslipidemia. We collected data from 5,134,036 participants from 137 prospective cohort studies. For the independent variable, we categorized participants at baseline as having long sleep duration or normal sleep duration. Risk ratios (RRs) for mortality and incident health conditions during follow-up were calculated through meta-analyses of adjusted data from individual studies. Meta-regression analyses were performed to investigate the association between each outcome and specific thresholds of long sleep. Long sleep was significantly associated with mortality (RR, 1.39; 95% CI, 1.31-1.47), incident diabetes mellitus (1.26, 1.11-1.43), cardiovascular disease (1.25, 1.14-1.37), stroke (1.46, 1.26-1.69), coronary heart disease (1.24, 1.13-1.37), and obesity (1.08, 1.02-1.15). Long sleep was not significantly related to incident hypertension (1.01, 0.95-1.07). Insufficient data were available for depression and dyslipidemia. Meta-regression analyses found statistically significant linear associations between longer sleep duration and increased mortality and incident cardiovascular disease. Future studies should address whether the relationship between long sleep and health outcomes is causal and modifiable.

Sleep duration and risk of all-cause mortality: A flexible, non-linear, meta-regression of 40 prospective cohort studies

Approximately 27-37% of the general population experience prolonged sleep duration and 12-16% report shortened sleep duration. However, prolonged or shortened sleep duration may be associated with serious health problems. A comprehensive, flexible, non-linear meta-regression with restricted cubic spline (RCS) was used to investigate the dose-response relationship between sleep duration and all-cause mortality in adults. Medline (Ovid), Embase, EBSCOhost-PsycINFO, and EBSCOhost-CINAHL Plus databases, reference lists of relevant review articles, and included studies were searched up to Nov. 29, 2015. Prospective cohort studies investigating the association between sleep duration and all-cause mortality in adults with at least three categories of sleep duration were eligible for inclusion. We eventually included in our study 40 cohort studies enrolling 2,200,425 participants with 271,507 deaths. A J-shaped association between sleep duration and all-cause mortality was present: compared with 7 h of sleep (reference for 24-h sleep duration), both shortened and prolonged sleep durations were associated with increased risk of all-cause mortality (4 h: relative risk [RR] = 1.05; 95% confidence interval [CI] = 1.02-1.07; 5 h: RR = 1.06; 95% CI = 1.03-1.09; 6 h: RR = 1.04; 95% CI = 1.03-1.06; 8 h: RR = 1.03; 95% CI = 1.02-1.05; 9 h: RR = 1.13; 95% CI = 1.10-1.16; 10 h: RR = 1.25; 95% CI = 1.22-1.28; 11 h: RR = 1.38; 95% CI = 1.33-1.44; n = 29; P < 0.01 for non-linear test). With regard to the night-sleep duration, prolonged night-sleep duration was associated with increased all-cause mortality (8 h: RR = 1.01; 95% CI = 0.99-1.02; 9 h: RR = 1.08; 95% CI = 1.05-1.11; 10 h: RR = 1.24; 95% CI = 1.21-1.28; n = 13; P < 0.01 for non-linear test). Subgroup analysis showed females with short sleep duration a day (<7 h) were at high risk of all-cause mortality (4 h: RR = 1.07; 95% CI = 1.02-1.13; 5 h: RR = 1.08; 95% CI = 1.03-1.14; 6 h: RR = 1.05; 95% CI = 1.02-1.09), but males were not (4 h: RR = 1.01; 95% CI = 0.96-1.06; 5 h: RR = 1.02; 95% CI = 0.97-1.08; 6 h: RR = 1.02; 95% CI = 0.98-1.06). The current evidence suggests that insufficient or prolonged sleep may increase all-cause mortality. Women may be more susceptible to short sleep duration on all-cause mortality.

Nighttime sleep duration, 24-hour sleep duration and risk of all-cause mortality among adults: a meta-analysis of prospective cohort studies

A dose-response meta-analysis was conducted to summarize evidence from prospective cohort studies about the association of nighttime sleep duration and 24-hour sleep duration with risk of all-cause mortality among adults. Pertinent studies were identified by a search of Embase and PubMed databases to March 2015. A two-stage random-effects dose-response meta-analysis was used to combine study-specific relative risks and 95% confidence intervals [RRs (95% CIs)]. Thirty-five articles were included. Compared with 7 hours/day, the RRs (95% CIs) of all-cause mortality were 1.07 (1.03-1.13), 1.04 (1.01-1.07), 1.01 (1.00-1.02), 1.07 (1.06-1.09), 1.21 (1.18-1.24), 1.37 (1.32-1.42) and 1.55 (1.47-1.63) for 4, 5, 6, 8, 9, 10 and 11 hours/day of nighttime sleep, respectively (146,830 death cases among 1,526,609 participants), and the risks were 1.09 (1.04-1.14), 1.05 (1.02-1.09), 1.02 (1.00-1.03), 1.08 (1.05-1.10), 1.27 (1.20-1.36), 1.53 (1.38-1.70) and 1.84 (1.59-2.13) for 4, 5, 6, 8, 9, 10 and 11 hours/day of 24-hour sleep, respectively (101,641 death cases among 903,727 participants). The above relationships were also found in subjects without cardiovascular diseases and cancer at baseline, and other covariates did not influence the relationships substantially. The results suggested that 7 hours/day of sleep duration should be recommended to prevent premature death among adults.

Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society on the Recommended Amount of Sleep for a Healthy Adult: Methodology and Discussion

The American Academy of Sleep Medicine and Sleep Research Society recently released a Consensus Statement regarding the recommended amount of sleep to promote optimal health in adults. This paper describes the methodology, background literature, voting process, and voting results for the consensus statement. In addition, we address important assumptions and challenges encountered during the consensus process. Finally, we outline future directions that will advance our understanding of sleep need and place sleep duration in the broader context of sleep health.

Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society on the Recommended Amount of Sleep for a Healthy Adult: Methodology and Discussion

The American Academy of Sleep Medicine and Sleep Research Society recently released a Consensus Statement regarding the recommended amount of sleep to promote optimal health in adults. This paper describes the methodology, background literature, voting process, and voting results for the consensus statement. In addition, we address important assumptions and challenges encountered during the consensus process. Finally, we outline future directions that will advance our understanding of sleep need and place sleep duration in the broader context of sleep health.

Sleep disturbances, TBI and PTSD: Implications for treatment and recovery

Post-Traumatic Stress Disorder (PTSD), traumatic brain injury (TBI), and sleep problems significantly affect recovery and functional status in military personnel and Veterans returning from combat. Despite recent attention, sleep is understudied in the Veteran population. Few treatments and rehabilitation protocols target sleep, although poor sleep remains at clinical levels and continues to adversely impact functioning even after the resolution of PTSD or mild TBI symptoms. Recent developments in non-pharmacologic sleep treatments have proven efficacious as stand-alone interventions and have potential to improve treatment outcomes by augmenting traditional behavioral and cognitive therapies. This review discusses the extensive scope of work in the area of sleep as it relates to TBI and PTSD, including pathophysiology and neurobiology of sleep; existing and emerging treatment options; as well as methodological issues in sleep measurements for TBI and PTSD. Understanding sleep problems and their role in the development and maintenance of PTSD and TBI symptoms may lead to improvement in overall treatment outcomes while offering a non-stigmatizing entry in mental health services and make current treatments more comprehensive by helping to address a broader spectrum of difficulties.