Sleep duration, insomnia, and markers of systemic inflammation: results from the Netherlands Study of Depression and Anxiety (NESDA)

Stress and Sleep Duration in Immune and Neuroendocrine Patterning. An Analytical Triangulation in ELSA

Background

Proinflammatory and neuroendocrine mediators are implicated in disease aetiopathogenesis. Stress increases concentrations of immune-neuroendocrine biomarkers through a complex network of brain-body signalling pathways. Suboptimal sleep further modulates these processes by altering major effector systems that sensitise the brain to stress. Given the ubiquitous, impactful nature of material deprivation, we tested for a synergistic association of financial stress and suboptimal sleep with these molecular processes.

Methods

With data drawn from the English Longitudinal Study of Ageing (ELSA), associations were tested on 4,940 participants (~66±9.4 years) across four-years (2008-2012). Through analytical triangulation, we tested whether financial stress (>60% insufficient resources) and suboptimal sleep (≤5/≥9 hours) were independently and interactively associated with immune-neuroendocrine profiles, derived from a latent profile analysis (LPA) of C-reactive protein, fibrinogen, white blood cell counts, hair cortisol, and insulin-like growth factor-1.

Results

A three-class LPA model offered the greatest parsimony. After adjustment for genetic predisposition, sociodemographics, lifestyle, and health, financial stress was associated with short-sleep cross-sectionally (RRR=1.45; 95%CI=1.18-1.79; p<0.001) and longitudinally (RRR=1.31; 95%CI=1.02-1.68; p=0.035), and it increased risk of belonging to the high-risk biomarker profile by 42% (95%CI=1.12-1.80; p=0.004). Suboptimal sleep was not related to future risk of high-risk profile membership, nor did it moderate financial stress-biomarker profile associations.

Discussion

Results advance psychoneuroimmunological knowledge by revealing how immune-neuroendocrine markers cluster in older cohorts and respond to financial stress over time. Financial stress associations with short-sleep are supported. The null role of suboptimal sleep, as exposure and mediator, in profile membership, provides valuable insight into the dynamic role of sleep in immune-neuroendocrine processes.

Examining Anxiety and Insomnia in Internship Students and Their Association with Internet Gaming Disorder

Background: Internships are a mandatory graduation requirement to help medical students transition to the work environment. Some individuals are prone to anxiety in an unfamiliar environment, which is a public concern among young adults. Here, we investigated the mechanism between internet gaming disorder and anxiety and insomnia among internship students. Methods: A convenient sample of 267 internship students was collected in a cross-sectional study module between 17 July and 27 December 2022. The survey contained a 7-item Generalized Anxiety Disorder (GAD-7), Athens Insomnia Scale (AIS), and Internet Gaming Disorder Scale-Short-Form (IGDS9-SF). The association was estimated using Pearson's correlations, and network analysis was performed to characterize these associations. Results: Our results indicate that about 60% of participants exhibited mild to severe anxiety and insomnia, while 2.28% showed symptoms of internet gaming disorder. Also, we found a moderate association between anxiety and insomnia. An item-level analysis indicated that GAD_1 "feeling anxious" and GAD_5 "unable to sit still" are essential for gaming, and that GAD_2 "uncontrollable worrying" is crucial for insomnia. This indicated an interplay between these items, supported by our centrality analysis, where we found that GAD_1 and GAD_2 depicted high centrality. Conclusions: We found high rates of anxiety and insomnia in internship students and the association between selected symptoms of anxiety and insomnia. At the same time, low rates of internet gaming disorder could be attributed to a lack of time for entertainment and an increased awareness of its risks. Given these findings, an awareness of anxiety and insomnia risk should be emphasized.

No causal association between insomnia and bladder cancer: a bidirectional two-sample Mendelian randomization study

BACKGROUND

Previous observational studies have indicated a potential link between insomnia and bladder cancer, yet the underlying causal relationship remains uncertain. The current study employed a bidirectional two-sample Mendelian randomization (MR) analysis to investigate this association.

METHODS

A two-sample MR analysis was conducted utilizing publicly available summary data from genome-wide association studies (GWAS) on insomnia and bladder cancer. Various regression methods including the inverse variance weighted (IVW), weighted median, MR-Egger, weighted mode, and simple mode methods were employed for the MR analysis. The presence of pleiotropy and heterogeneity in the MR results was also assessed. Furthermore, additional sensitivity tests were performed to mitigate potential biases.

RESULTS

No significant causal relationship was detected between insomnia and bladder cancer using IVW method (OR = 0.761, 95% CI 0.996-1.005; P = 0.76). Similarly, the IVW model did not reveal any causal effect of bladder cancer on the risk of insomnia (OR = 1.47, 95% CI 0.772-2.799; P = 0.24). Consistent results were obtained from the other four methods employed. There was no evidence of horizontal pleiotropy or heterogeneity in our MR analysis (P > 0.05). The sensitivity analyses further supported the reliability of the estimated causal effects.

CONCLUSIONS

This study presents no evidence for a causal relationship between insomnia and bladder cancer.

Circadian rhythm regulates the function of immune cells and participates in the development of tumors

Circadian rhythms are present in almost all cells and play a crucial role in regulating various biological processes. Maintaining a stable circadian rhythm is essential for overall health. Disruption of this rhythm can alter the expression of clock genes and cancer-related genes, and affect many metabolic pathways and factors, thereby affecting the function of the immune system and contributing to the occurrence and progression of tumors. This paper aims to elucidate the regulatory effects of BMAL1, clock and other clock genes on immune cells, and reveal the molecular mechanism of circadian rhythm's involvement in tumor and its microenvironment regulation. A deeper understanding of circadian rhythms has the potential to provide new strategies for the treatment of cancer and other immune-related diseases.

Association of Biomarkers of Neuronal Injury and Inflammation With Insomnia Trajectories After Traumatic Brain Injury: A TRACK-TBI Study

BACKGROUND AND OBJECTIVES

Insomnia affects about one-third of patients with traumatic brain injury and is associated with worsened outcomes after injury. We hypothesized that higher levels of plasma neuroinflammation biomarkers at the time of TBI would be associated with worse 12-month insomnia trajectories.

METHODS

Participants were prospectively enrolled from 18 level-1 trauma centers participating in the Transforming Research and Clinical Knowledge in Traumatic Brain Injury study from February 26, 2014, to August 8, 2018. Plasma glial fibrillary acidic protein (GFAP), high-sensitivity C-reactive protein (hsCRP), S100b, neuron-specific enolase (NSE), and ubiquitin carboxyl-terminal hydrolase-L1 (UCH-L1) were collected on days 1 (D1) and 14 (D14) after TBI. The insomnia severity index was collected at 2 weeks, 3, 6, and 12 months postinjury. Participants were classified into insomnia trajectory classes based on a latent class model. We assessed the association of biomarkers with insomnia trajectories, controlling for medical and psychological comorbidities and demographics.

RESULTS

Two thousand twenty-two individuals with TBI were studied. Elevations in D1 hsCRP were associated with persistent insomnia (severe, odds ratio [OR] = 1.33 [1.11, 1.59], p = 0.002; mild, OR = 1.10 [1.02, 1.19], p = 0.011). Similarly, D14 hsCRP elevations were associated with persistent insomnia (severe, OR = 1.27 [1.02, 1.59], p = 0.03). Of interest, D1 GFAP was lower in persistent severe insomnia (median [Q1, Q3]: 154 [19, 445] pg/mL) compared with resolving mild (491 [154, 1,423], p < 0.001) and persistent mild (344 [79, 1,287], p < 0.001). D14 GFAP was similarly lower in persistent (11.8 [6.4, 19.4], p = 0.001) and resolving (13.9 [10.3, 20.7], p = 0.011) severe insomnia compared with resolving mild (20.6 [12.4, 39.6]. Accordingly, increases in D1 GFAP were associated with reduced likelihood of having persistent severe (OR = 0.76 [95% CI 0.63-0.92], p = 0.004) and persistent mild (OR = 0.88 [0.81, 0.96], p = 0.003) compared with mild resolving insomnia. No differences were found with other biomarkers.

DISCUSSION

Elevated plasma hsCRP and, surprisingly, lower GFAP were associated with adverse insomnia trajectories after TBI. Results support future prospective studies to examine their utility in guiding insomnia care after TBI. Further work is needed to explore potential mechanistic connections between GFAP levels and the adverse insomnia trajectories.

Relationship between dietary carotenoid intake and sleep duration in American adults: a population-based study

OBJECTIVE

To investigate the relationship between dietary carotenoid intake and sleep duration.

METHODS

Adults enrolled in the National Health and Nutrition Examination Survey (NHANES) 2007-2018 without missing information on dietary carotenoid intake (α-carotene, β-carotene, β-cryptoxanthin, lycopene, and lutein + zeaxanthin), sleep duration, and covariates were included. Participants' carotenoid consumption was divided into three groups by quartiles and sleep duration was grouped as short (< 7 h/night), optimal (7-8 h/night), and long (> 8 h/night). Multinominal logistic regression was constructed to examine the association between dietary carotenoid intake and sleep duration. Restricted cubic spline (RCS) regression was further utilized to explore their dose-response relationship. The weighted quantile sum (WQS) model was adopted to calculate the mixed and individual effect of 5 carotenoid sub-types on sleep duration.

RESULTS

Multinominal logistic regression presented that people with higher intakes of α-carotene, β-carotene, β-cryptoxanthin, lycopene, and lutein + zeaxanthin were less likely to sleep too short or too long. Consistent with the findings from multinominal logistic regression, the RCS models suggested a reverse U-shaped relationship between sleep duration and carotenoid intakes. The mixed effects were also significant, where β-cryptoxanthin and lutein + zeaxanthin were the top 2 contributors associated with the decreased risks of short sleep duration, while β-carotene, α-carotene, and β-cryptoxanthin were the main factors related to the lower risk of long sleep duration.

CONCLUSION

Our study revealed that the American adults with optimal sleep duration were associated with more dietary carotenoid intake, in comparison to short or long sleepers.

Combined Use of Sleep Quality and Duration Is More Closely Associated With Mortality Risk Among Older Adults: A Population-based Kyoto-Kameoka Prospective Cohort Study

BACKGROUND

Whether sleep quality and duration assessed from multiple domains, either individually or in combination, are strongly associated with mortality risk in older adults remains unelucidated. We aimed to clarify these relationships.

METHODS

We enrolled 7,668 older (age ≥65 years) Japanese adults in the Kyoto-Kameoka prospective cohort study who provided valid responses to the Pittsburgh Sleep Quality Index (PSQI) in a mail-in survey. Sleep quality and duration were classified into six groups using the previously validated PSQI: short sleep duration (SSD: <360 min/day)/sleep disturbance (SD: ≥5.5 PSQI points), n = 701; SSD/non-sleep disturbance (NSD: <5.5 PSQI points), n = 100; optimal sleep duration (OSD: 360-480 min/day)/NSD, n = 1,863; OSD/SD, n = 2,113; long sleep duration (LSD: >480 min/day)/NSD, n = 1,972; LSD/SD, n = 919. Mortality data were collected from February 15, 2012, to November 30, 2016. We evaluated the relationship between all-cause mortality risk and sleep quality and duration (and their combinations) using a multivariable Cox proportional hazards model that included baseline covariates.

RESULTS

The median follow-up period was 4.75 years (34,826 person-years), with a total of 616 deaths. After adjusting for confounders, compared with other groups, SSD/SD and LSD/SD had the highest hazard ratio (HR) of mortality (SSD/SD: HR 1.56; 95% confidence interval [CI], 1.10-2.19; SSD/NSD: HR 1.27; 95% CI, 0.47-3.48; OSD/NSD: reference; OSD/SD: HR 1.20; 95% CI, 0.91-1.59; LSD/NSD: HR 1.35; 95% CI, 1.03-1.77; LSD/SD: HR 1.83; 95% CI, 1.37-2.45). However, mortality risk was not associated with the interaction between sleep quality and duration.

CONCLUSION

Older adults with sleep disturbances involving SSD and LSD have a strong positive association with mortality risk, suggesting an additive effect between sleep quality and duration.

Effects of Walking Combined With Resistance Band Exercises on Alleviating Cancer-Related Fatigue: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

Cancer-related fatigue (CRF) is a common symptom, and exercise has shown potential in alleviating CRF. However, there is a need for diverse exercise options tailored to individual patient needs.

OBJECTIVE

To evaluate the overall effects of a combined walking and resistance band exercise intervention in relieving CRF among cancer patients through randomized controlled trials.

METHODS

Comprehensive searches were conducted in multiple databases to identify relevant studies up until March 2023. Inclusion criteria required the intervention to involve walking combined with elastic band training, with a clear exercise protocol description. The primary outcome was CRF, and secondary outcomes included walking steps, distance, mood distress, and quality of life. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated using random-effects models.

RESULTS

Ten trials were included. The intervention group showed significant improvements in CRF (SMD, -0.40; 95% CI, -0.60 to -0.20), mood distress (SMD, -0.30; 95% CI, -0.53 to -0.07), and daily walking steps (SMD, 0.52; 95% CI, 0.07-0.96) compared with the control group. Although the 6-Minute Walk Test and quality of life did not show significant differences, a trend toward improvement was observed in the intervention group. Adverse events related to the intervention were infrequent.

CONCLUSION

A combined walking and resistance band exercise intervention can effectively alleviate CRF and improve mood distress and daily walking steps among cancer patients.

IMPLICATIONS FOR PRACTICE

This exercise option may provide an additional strategy to manage CRF. Further research is needed to explore the optimal exercise prescription for individual patients.

Insomnia trajectories predict chronic inflammation over 2 years at the transition to adulthood

Insomnia in adolescents is an important public health concern, as its impacts on both their current and future physical and mental health has been discussed. However, few longitudinal studies have examined insomnia and chronic inflammation at the transition from adolescence to adulthood. This study aimed to examine the predictive effects of insomnia and insomnia trajectories on inflammation in college students by using a prospective design. Using data from the College Student Behaviour and Health Cohort Study, which was conducted between April 2019 and April 2021, with an interval of 6 months. We investigated the associations between insomnia trajectories from Year 1 to Year 3 and five inflammatory biomarkers (C-reactive protein [CRP], tumour necrosis factor [TNF]-α, interleukin [IL]-6, IL-1β, IL-10) at Year 3. The association of insomnia symptoms at baseline, Wave 1 or Wave 2 with inflammatory biomarkers at Wave 4 were also assessed. A total of 312 college students (males: 51.6%) aged 16-26 years (mean [SD] 18.82 [1.22] years) were analysed. We identified two insomnia trajectory classes: increasing insomnia (n = 63 [20.2%]) and decreasing insomnia (n = 249 [79.8%]). Generalised linear model analysis revealed that insomnia symptoms at Wave 1 were associated with significantly elevated CRP and TNF-α levels at Wave 4. Increasing insomnia trajectories predicted consistently higher levels of CRP, TNF-α and IL-10. However, after adjusting for potential confounders, these associations were significantly attenuated. Overall, the findings suggest that insomnia symptoms affect chronic inflammation at the transition to adulthood. Our study needs to be replicated in larger cohorts to further explore how inflammation interacts with insomnia to increase the susceptibility to adverse health conditions.

Sleep disturbances and the risk of lung cancer: a meta-epidemiological study

BACKGROUND

The relationship between sleep disturbances and lung cancer is complex and bidirectional. This meta-epidemiological study aimed to explore the potential association between sleep disruption and the risk of pulmonary cancer.

METHODS

We conducted a comprehensive literature search of the PubMed, Embase, Cochrane Library, and Web of Science databases to retrieve relevant studies. We employed the Newcastle-Ottawa Scale to assess the quality of the observational studies. Stata 17.0 was used to synthesize and conduct a meta-analysis of odds ratios (ORs) and corresponding 95% confidence intervals (CIs). We used funnel plot analysis and Egger's regression test to evaluate potential publication bias.

RESULTS

A total of 11 studies were included with 469,691 participants. The methodological quality of the included studies ranged from moderate to high. Compared with 7-8 h of sleep time, short sleep duration was associated with a 13% higher lung cancer risk [OR, 1.13; 95%CI: 1.02-1.25; I2 = 67.6%; P = 0.018] and long sleep duration with a 22% higher risk [OR, 1.22; 95%CI: 1.12-1.33; I2 = 6.9%; P < 0.001]. Insomnia symptoms [OR, 1.11; 95%CI: 1.07-1.16; I2 = 0%; P < 0.001] and evening chronotype [OR, 1.15; 95%CI: 1.05-1.26; P = 0.002] were all related to a higher risk of lung cancer. Egger's test revealed no publication bias for sleep duration (P = 0.13).

DISCUSSION

This systematic review is the first one which observes positive correction between sleep disturbances and the incidence of lung cancer. While the plausible mechanism is not clear, it is hypothesized that the association of short sleep duration and lung cancer mainly mediated by melatonin secretion and the immune-inflammatory balance. Further studies are needed to examine whether other risk factors, such as age, occupation, cumulative effect of sleep disturbances might mediate the relationship between sleep disturbances and lung cancer risk.

CONCLUSION

The present study revealed that insufficient and excessive sleep duration, insomnia symptoms, and evening chronotype were significantly predictive of an increased risk of lung cancer. This finding underscores the need to account for sleep disturbances as an independent risk factor for evaluating susceptibility to lung cancer.

TRIAL REGISTRATION

CRD42023405351.

Assoication between self-reported sleep duration, physcial activity and the risk of all cause and cardiovascular diseases mortality from the NHANES database

OBJECTIVE

The purpose of this study was to investigate the combined effect of self-reported sleep durations and physical activity (PA) on all cause and cardiovascular diseases mortality.

METHODS

Twenty-nine thousand fifty-eight participants (48.5% male, median age 49 years) from the National Health and Nutrition Examination Survey cycles 2007 to 2016 were included. We classified sleep duration into five categories (< 5.5 h/d,5.5-6.5 h/d,6.5-7.5 h/d,7.5-8.5 h/d, ≥ 8.5 h/d) and classified PA levels into three groups (high, medium and low). PA information and self-reported sleep duration were obtained by questionnaire. We derived 15 PA-sleep duration combinations. The primary endpoint was all-cause mortality, and the major secondary endpoint was cardiovascular diseases (CVD) mortality as of December 2022.

RESULTS

Median follow-up was 91 months. Compared with standard sleep duration (6.5-7.5 h/d), both shorter (< 5.5 h/d) and longer (≥ 8.5 h/d) sleep durations increased risks of all-cause mortality and CVD mortality in low PA. The deleterious associations of sleep duration with all outcomes was amplified by lower PA. There was no significant reduction in CVD mortality risk associated with increased physical activity during short sleep duration (< 6.5 h/d). During standard sleep, low PA significantly increased CVD mortality risk. At medium physical activity, both short and long sleep increased cardiovascular mortality. It was also found that sleep duration (≥ 8.5 h/d) was associated with a increase in all-cause and cardiovascular mortality at both low and high PA levels.

CONCLUSIONS

This study suggested that low PA significantly increased the association of self-reported long and short sleep durations with all-cause and CVD mortality. All cause mortality appears to benefit from medium physical activity, while medium PA did not. Physical activity did not significantly reduce the risk of CVD mortality.

Longitudinal Trends in Sleep and Related Factors Among South Korean Adults From 2009 to 2018

BACKGROUND AND PURPOSE

Excess or insufficient sleep, irregular sleep-wake patterns, and an extreme early or late chronotypes adversely impact physical and mental health. Changes in sleep characteristics should therefore be tracked, and factors that contribute to poor sleep should be identified. We investigated the changes in sleep patterns among South Korean adults during 2009-2018.

METHODS

Using data of a representative sample of South Korean adults from the 2009 (n=2,658, 48.5% males; age=44.5±15.0 years old [mean±standard deviation], age range=19-86 years) and 2018 (n=2,389, 49.1% males; age=47.9±16.3 years, age range=19-92 years) Korean Headache-Sleep Study, we explored changes in sleep timing, sleep duration, chronotype, and social jetlag (SJL). Logistic regression analysis was used to examine the association between average sleep duration and depression.

RESULTS

From 2009 to 2018, bedtimes were advanced by 10 and 25 min on workdays and free days, respectively. Meanwhile, wake-up times were advanced by 13 min and delayed by 12 min on workdays and free days, respectively. The average sleep duration significantly decreased from 7.45 h to 7.13 h. The prevalence of short sleep duration (<7 h) increased, whereas that of long sleep duration (≥8 h) decreased. A circadian preference toward eveningness and SJL increased. The prevalence of depression increased from 4.6% to 8.4%, and there were significant reverse J-shaped and U-shaped associations between average sleep duration and depression in 2009 and 2018, respectively.

CONCLUSIONS

Changes in sleep patterns and the association between sleep duration and depressive mood were determined from a representative sample of the South Korean adult population. Interventions to modify sleep behaviors might improve public health.

All-cause and major-cause mortality associated with sleep latency in the Korean Genome and Epidemiology Study (KoGES): a population-based prospective cohort study

BACKGROUND

The all-cause and cause-specific mortality risk associated with sleep latencies in the general adult population is unknown. We aimed to investigate the association of habitual prolonged sleep latency with long-term all-cause and cause-specific mortality in adults.

METHODS

The Korean Genome and Epidemiology Study (KoGES) is a population-based prospective cohort study comprising community-dwelling men and women aged 40-69 years from Ansan, South Korea. The cohort was studied bi-annually from April 17, 2003, to Dec 15, 2020, and the current analysis included all individuals who completed the Pittsburgh Sleep Quality Index (PSQI) questionnaire between April 17, 2003, and Feb 23, 2005. The final study population comprised 3757 participants. Data were analysed from Aug 1, 2021, to May 31, 2022. The main exposure was sleep latency groups based on the PSQI questionnaire: fell asleep in 15 min or less, fell asleep in 16-30 min, occasional prolonged sleep latency (fell asleep in >30 min once or twice a week in the past month) and habitual prolonged sleep latency (fell asleep in >60 min more than once a week or fell asleep in >30 min ≥3 times a week, or both) in the past month at baseline. Outcomes were all-cause and cause-specific (cancer, cardiovascular disease, and other causes) mortality reported during the 18-year study period. Cox proportional hazards regression models were used to examine the prospective relationship between sleep latency and all-cause mortality, and competing risk analyses were done to investigate the association of sleep latency with cause-specific mortality.

FINDINGS

During a median follow-up of 16·7 years (IQR 16·3-17·4), 226 deaths were reported. After adjusting for demographic characteristics, physical characteristics, lifestyle factors, chronic conditions, and sleep variables, self-reported habitual prolonged sleep latency was associated with an increased risk of all-cause mortality (hazard ratio [HR] 2·22, 95% CI 1·38-3·57) compared to the reference group (those who fell asleep in 16-30 min). In the fully adjusted model, habitual prolonged sleep latency was associated with a more than doubled risk of dying from cancer compared to the reference group (HR 2·74, 95% CI 1·29-5·82). No significant association was observed between habitual prolonged sleep latency and deaths from cardiovascular disease and other causes.

INTERPRETATION

In this population-based prospective cohort study, habitual prolonged sleep latency was independently associated with an increased risk of all-cause and cancer-specific mortality in adults (independently of demographic characteristics, lifestyle factors, chronic morbidities, and other sleep variables). Although further studies are warranted to investigate the causality of the relationship, strategies or interventions to prevent habitual prolonged sleep latencies might enhance longevity in the general adult population.

FUNDING

Korea Centers for Disease Control and Prevention.

Transdiagnostic factors predicting the 2-year disability outcome in patients with anxiety and depressive disorders

BACKGROUND

Both anxiety and depressive disorders are associated with significant long-term disability. Since experienced impairments vary between patients independent of diagnosis and disease severity, identifying transdiagnostic factors that predict the course of disability may provide new targets to reduce disability. This study examines transdiagnostic factors predicting the 2-year disability outcome in patients with anxiety and/or depressive disorders (ADD), focusing on potentially malleable factors.

METHODS

Six hundred fifteen participants with a current diagnosis of ADD from the Netherlands Study of Depression and Anxiety (NESDA) were included. Disability was assessed at baseline and after 2 years of follow-up, using the 32-item WHODAS II questionnaire. Transdiagnostic predictors of 2-year disability outcome were identified using linear regression analysis.

RESULTS

In univariable analyses, transdiagnostic factors associated with the 2-year disability outcome were locus of control (standardized β = -0.116, p = 0.011), extraversion (standardized β = -0.123 p = 0.004) and experiential avoidance (standardized β = 0.139, p = 0.001). In multivariable analysis, extraversion had a unique predictive value (standardized β = -0.143 p = 0.003). A combination of sociodemographic, clinical and transdiagnostic variables resulted in an explained variance (R2) of 0.090). The explained variance of a combination of transdiagnostic factors was 0.050.

CONCLUSION

The studied transdiagnostic variables explain a small but unique part of variability in the 2-year disability outcome. Extraversion is the only malleable transdiagnostic factor predictive of the course of disability independent of other variables. Due to the small contribution to the variance in the disability outcome, the clinical relevance of targeting extraversion seems limited. However, its predictive value is comparable to that of accepted disease severity measures, supporting the importance of looking beyond using disease severity measures as predictors. Furthermore, studies including extraversion in combination with other transdiagnostic and environmental factors may elucidate the unexplained part of variability of the course of disability in patients with ADD.

Sleep duration trajectories and all-cause mortality among Chinese elderly: A community-based cohort study

BACKGROUND

China is among the largest and fastest aging countries. The elderly population is more vulnerable, with higher proportion of inappropriate sleep duration and risk of mortality, compared with young and middle-aged adults. Single-measured sleep duration has been associated with mortality, but the health effects of long-term sleep duration trajectories remain unknown. This study aimed to explore the prospective associations between sleep duration trajectories and all-cause mortality among Chinese elderly.

METHODS

Participants (n = 3,895; median age: 82 years; females: 53.3%) who reported sleep duration in all three surveys (2005, 2008, and 2011) from the community-based Chinese Longitudinal Healthy Longevity Survey (CLHLS) were followed up until 2019 (about 8 years). We identified sleep duration trajectories by latent class mixed model and explored their association with all-cause mortality using Cox hazard proportional regression and Laplace regression models. Further, stratified analysis by demographic characteristics and lifestyles and sensitivity analysis by lag effect, health-related factors, and inverse probability weighting were used to verify the robustness of the association. In addition, we explored the threshold effect of baseline sleep duration on the risk of all-cause mortality.

RESULTS

We documented 1,881 all-cause deaths during 16,689 person-years of follow-up. Five sleep duration trajectories were identified: moderately increased trajectory (28.1%), rapidly increased trajectory (7.2%), persistent sleep trajectory of 7 h (33.7%), moderately decreased trajectory (21.3%), and rapidly decreased trajectory (9.7%). Compared with the persistent sleep trajectory of 7 h, the multivariable-adjusted HRs (95%CI) for moderately increased trajectory, rapidly increased trajectory, moderately decreased trajectory, and rapidly decreased trajectory were 1.21 (1.08, 1.36), 1.21 (1.01, 1.44), 0.95 (0.82, 1.10), and 0.93 (0.78, 1.11), respectively; and the corresponding difference in median survival time (95%CI) were -0.53 (-1.01, -0.05), -0.43 (0.16, -1.02), 0.26 (-0.34, 0.86), and 0.25 (-0.51, 1.02), respectively. Stratified and sensitivity analyses showed consistent results. Threshold analysis indicated a sharply increased risk of mortality in participants whose sleep exceeds 9 h (HR = 1.20, 95%CI: 1.11, 1.30).

CONCLUSION

Compared with the persistent sleep trajectory of 7 h, moderately and rapidly increased sleep duration trajectories were associated with higher subsequent mortality in Chinese elderly. Those who report sleep exceeding 9 h may be at high risk for all-cause mortality.

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.

Unhealthy lifestyle impacts on biological systems involved in stress response: hypothalamic-pituitary-adrenal axis, inflammation and autonomous nervous system

An unhealthy lifestyle has a critical role in the pathogenesis and course of several chronic disorders. It has been hypothesized that lifestyle may also impact biological systems involved in stress response. A global index of unhealthy lifestyle was calculated based on the cumulative presence of five self-reported lifestyle habits (smoking, excessive alcohol use, drug use, low physical activity and short sleep) in 2783 participants (18-65 years) from the Netherlands Study of Depression and Anxiety. The functioning of biological stress systems was based on multiple physiological measures of cortisol, inflammatory cytokines and autonomic cardiac activity. The unhealthy lifestyle index was associated with hyperactivity of hypothalamus-pituitary-adrenal axis and increased inflammation, indicating that with increasing unhealthy habits, the level of biological stress increases. No association with the autonomic nervous system activity was observed; however, the use of drugs increased parasympathetic cardiac activity and significantly impacted on ANS. Results were not impacted by a recent episode of depression or anxiety disorder. An unhealthy lifestyle may unfavorably impact on biological systems involved in stress response, which may underlie progression of several psychiatric as well as somatic chronic disorders.

Functional connectivity between dorsal attention and default mode networks mediates subjective sleep duration and depression in young females

BACKGROUND

Depression prevails throughout the world. Young females are more likely to suffer from depression because of lack of sleep.

METHODS

We recruited 405 young female participants to assess their subjective sleep duration and self-rating depression. The resting-state magnetic resonance imaging (rs-fMRI) data were collected to identify the brain regions related to sleep duration and depression, and a mediating model was established among sleep duration, depression and functional connectivity (FC) of rs-fMRI.

RESULTS

Correlation analysis indicated that subjective sleep duration was negatively associated with self-rating depression in young females (r = -0.22, p < .001). The network connectivity between dorsal attention network (DAN) and default mode network (DMN) positively correlated with self-rating depression (r = 0.13, p < .05), and negatively correlated with subjective sleep duration (r = -0.14, p < .01). Furthermore, the mediation analysis revealed that the FC of DAN-DMN significantly mediated the effect of sleep duration on depression.

LIMITATIONS

The study was a cross-section design and the sleep duration of the participants was subjectively reported. Future studies should consider to track the participants longitudinally and to measure the objective sleep duration by actigraph or polysomnography.

CONCLUSIONS

The participants with less sleep duration are more prone to develop depression feelings. The FC of DAN-DMN mediated the effect of sleep duration on depression. Thus, the FC of DAN-DMN could be consider as a neural target to relieve depression by increasing sleep duration in young females.

Sleep duration, weekend catch-up sleep, and risk of obstructive sleep apnea in relation to handgrip strength

PURPOSE

This cross-sectional study aimed to evaluate whether weekday sleep duration, weekend catch-up sleep, and risk of obstructive sleep apnea are individually and in combination associated with handgrip strength.

METHODS

Data from the Korea National Health and Nutrition Examination Survey 2019, including weekday sleep duration, weekend catch-up sleep, STOP-BANG scores, relative handgrip strength (handgrip strength divided by body mass index), and confounding factors (sociodemographic factors, health behaviors, and health and nutritional status), were evaluated in 3678 Korean adults aged 40 to 80 years. Adequate (vs. inadequate) sleep parameters were defined as weekday sleep duration (6-7 vs. ≤ 5 or ≥ 8 h), weekend catch-up sleep (presence vs. absence), and risk of obstructive sleep apnea (low vs. high based on STOP-BANG scores). Sex-specific quintiles of relative handgrip strength were categorized as high (highest 5th quintile) or low (lower 1^st to 4^th quintiles). A complex-sample logistic regression analysis was performed.

RESULTS

After adjusting for other sleep parameters and confounding variables, each adequate sleep parameter individually and collectively was associated with high relative handgrip strength (adjusted odds ratios [95% confidence interval], 1.43 [1.09, 1.89] for 6-7 h weekday sleep duration; 1.44 [1.10, 1.90] for low risk of obstructive sleep apnea; 1.72 [1.23, 2.40] for any two parameters; 1.81 [1.18, 2.79] for all parameters). The combination of adequate weekend catch-up sleep and obstructive sleep apnea risk had the highest odds ratio for high relative handgrip strength (2.36 [1.45, 3.83]).

CONCLUSIONS

Adequate weekday sleep duration, weekend catch-up sleep, and low obstructive sleep apnea risk were individually and in combination associated with high handgrip strength.

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.

Relationship between genetic polymorphisms of cytokines and self-reported sleep complaints and habitual caffeine consumption

Pro-inflammatory cytokines are involved in sleep-wake regulation and are associated with caffeine consumption. This is a cross-sectional study in 1023 active French workers investigating associations between self-reported sleep complaints (>3months) and total sleep time (TST) with nine single-nucleotide-polymorphisms (SNPs) including pro-inflammatory cytokines, according to caffeine consumption. Participants were characterized as low, moderate and high (0-50, 51-300, and >300 mg/day) caffeine consumers. After adjusting the odd ratios (OR) for age, gender, and smoking, the risk of sleep complaints was higher in subjects with genetic mutations in tumor necrosis factor alpha (TNF-α, rs 1800629) (ORa [95%CI] = 1.43 [1.07-1.92] for both G/A and A/A aggregate genotypes) or interleukin-1 beta (IL-1β, rs1143627) (ORa = 1.61 [1.08-2.44] for homozygous A/A genotype), and the risk was higher when subjects carry the mutations in TNF-α plus IL-1β regardless of caffeine consumption. When stratified with caffeine consumption, the risk of sleep complaints was higher in TNF-α A allele carriers in high caffeine consumers, and in homozygous A/A genotype of IL-1β in moderate and high consumers. None of the nine SNPs influence TST, with the exception of the mutation on CYP1A2 and only when stratified with caffeine consumption. Our results also indicated more caffeine side-effects when carrying mutation on IL1β. This study showed that polymorphisms in TNF-α and/or IL-1β influenced sleep complaints but did not influence total sleep time. This suggests that management of sleep complaints, which can be addressed by clinical interventions, should consider the influence of the genetic profile of pro-inflammatory cytokines.

Associations among acute and chronic musculoskeletal pain, sleep duration, and C-reactive protein (CRP): A cross-sectional study of the UK biobank dataset

Both musculoskeletal pain and sleep disturbances are major health problems worldwide. Literature suggests that the two are reciprocally related and both may be associated with changes in C-reactive protein (CRP) levels. However, the relationships among musculoskeletal pain, sleep duration, and CRP remain unclear. In this cross-sectional study, we investigated the relationship between acute and chronic musculoskeletal pain, sleep, and inflammation using the data from the initial visit of the UK Biobank. 17,642 individuals with chronic musculoskeletal pain, 11,962 individuals with acute musculoskeletal pain, and 29,604 pain-free controls were included in the analysis. In addition, we validated the findings using data from the second visit assessment of the UK Biobank. We found that 1) chronic pain was associated with higher CRP levels compared to both acute pain and the pain-free controls; 2) chronic pain was associated with a lower sleep score (a measurement of sleep patterns), compared to acute pain and the pain-free controls; and acute pain was associated with lower sleep scores compared to the controls; 3) there was a significant negative association between the sleep score and CRP; 4) CRP may partially mediate the association between chronic pain and decreased sleep score. However, the effect size of the mediation was rather small, and the pathophysiological significance remains uncertain. Further validation is needed. These findings were partly replicated in the UK Biobank second visit assessment cohort with a smaller sample size. Our findings, which are based on the large UK Biobank dataset, support the interplay between musculoskeletal pain, sleep patterns, and the potential mediating role of CRP on this reciprocal relationship.

The economic costs of insomnia comorbid with depression and anxiety disorders: an observational study at a sleep clinic in Mexico

Significant advances documenting the costs associated with insomnia have been achieved. However, those related to insomnia associated with mood disorders remain understudied, even though insomnia is more severe in the presence of comorbid conditions such as depression and anxiety. The aim of this study was to determine the direct and indirect costs of insomnia associated with depression and anxiety disorders (DAD) from the perspective of the patient in a private healthcare system. This was an observational study of chronic insomnia associated with DAD at a private Sleep Disorders Clinic in Mexico City between 2019 and 2020. Patients were followed for up to one year. Healthcare resource utilization data were collected through clinical records. Direct and indirect costs associated with insomnia treatment were estimated through micro-costing. The estimated economic burden was projected to 5 years adjusting for inflation and discounting future costs. A deterministic sensitivity analysis was performed. The median cost of the first year of insomnia treatment associated with DAD was US$3537.57 per patient. The work productivity loss represented the highest economic burden (63.84%) followed by direct medical costs (28.32%), and the direct non-medical costs (7.85%). The estimated annual economic burden for patients treated in the private healthcare system in Mexico was US$293 million. The costs of insomnia associated with DAD at a private clinic in México were found to be high. The burden of the costs faced by these patients is substantial relative to the median income of the population. The economic costs at an individual and societal levels are substantial.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-022-00412-6.

Sleep Characteristics and Cancer-Related Outcomes: An Umbrella Review of Systematic Reviews and Meta-Analyses of Observational Studies

BACKGROUND

Sleep is closely related to various diseases. Several meta-analyses have provided evidence of sleep and cancer, and yet the credibility of this evidence has not been comprehensively quantified. Thus, we conducted an umbrella review to quantify the evidence for systematic reviews and meta-analyses of observational studies on sleep characteristics (sleep duration, sleep quality, napping, bedtime, and wake-up time) and cancer-related outcomes.

METHODS

PubMed, Web of Science (Core Collection), and Embase databases were searched from inception until 29 July 2022. Assessment of Multiple Systematic Reviews, version 1, was used to evaluate the methodological quality of each eligible systematic review or meta-analysis. For each association, the summary effect with a 95% confidence interval was evaluated by fixed and random effects models. The 95% prediction interval, heterogeneity, small-study effects, and excess significance bias were also evaluated. Evidence of the associations from systematic reviews and meta-analyses was ranked based on the established criteria of published literature as convincing, highly suggestive, suggestive, weak, or non-significant.

RESULTS

The umbrella review identified thirty meta-analyses on the aforementioned associations from six articles. The methodological quality of five articles was high or moderate. Suggestive evidence was found for associations between long sleep duration and a 21% increased risk of colorectal cancer, a 9% increased all-cancer mortality and a 65% increased mortality of lung cancer, and associations between short sleep duration and a 21% increased mortality of lung cancer. Additionally, the evidence of associations between short sleep duration and lung cancer mortality was upgraded to convincing, and between long sleep duration and lung cancer mortality was upgraded to highly suggestive, among the population reporting 24 h sleep duration.

CONCLUSION

Abnormal sleep duration might be linked to several adverse cancer-related outcomes.

Sleep quality traits correlate with inflammatory markers in the breast tissue of women

BACKGROUND

Several mechanisms have been posited to play a role in the sleep and breast cancer association, including alterations in immune function, but evidence remains inconclusive. A closer look at how sleep quality traits affect the breast microenvironment may provide clues for molecular mechanisms underlying the link between sleep and breast cancer. We examined the association between sleep quality traits (sleep duration, sleep aids, and insomnia) and tissue-based protein levels and gene expression of several inflammatory markers associated with breast cancer.

METHODS

Breast tissues (normal n = 165 and adipose n = 74) were surgically obtained from women diagnosed with breast cancer. Protein levels by immunohistochemistry were determined using the quickscore method for 11 inflammatory markers in the normal epithelial breast tissue (interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), cyclooxygenase-2 (COX-2), leptin, serum amyloid A1 (SAA1), lactoferrin, transforming growth factor-beta (TGF-β), and signal transducer and activator of transcription 3 markers (STAT3). Relative quantification of 4 genes (COX-2, IL-6, TNF-α and LEP) in the adipose breast tissue was carried out using qPCR. Patient characteristics and sleep traits (average sleep duration per night, taking sleeping aids in the past year, and the average number of insomnia episodes per month) were determined by telephone interview. Associations were tested using Spearman's rank correlation (r_s) coefficients adjusted (ar_s) for age at surgery, menopausal status and PCR batch when applicable. Sleep duration categories (<7, 7-9, >9 h) and root- or log-transformed biomarker levels were examined with adjusted linear mixed models.

RESULTS

TGF-β and CRP levels in normal epithelial breast tissue were positively correlated with sleep aids (ar_s = 0.28, p = 0.013), and insomnia (ar_s = 0.23, p = 0.044) in postmenopausal women, respectively. IL-6 in the adipose breast tissue was inversely correlated with sleep aids (ar_s = -0.26, p = 0.029) in all women. None of the sleep traits significantly correlated with inflammatory markers in premenopausal women. Several markers tended to correlate at 0.05 ≥ p ≤ 0.10. Adjusted mean levels of inflammatory markers were significantly different across sleep duration categories (<7, 7-9, >9 h). Higher mean levels of IL-6, CRP, IL-10, and IL-6 and COX-2 expression were noted in the breast tissues of women sleeping < 7, and particularly, >9 h per night (p < 0.05).

CONCLUSION

Our findings indicate that sleep duration, sleep aids, and insomnia may differently affect women's breast tissues depending on menopausal status. From a public health perspective, these results warrant further validation in larger studies. Since sleep is a modifiable factor, it may be an interesting approach for breast cancer prevention.

Sleep duration and incident and persistent depressive symptoms among a rural ageing population in South Africa

BACKGROUND

The aim of the study was to assess the relationship between sleep duration and incident depressive symptoms (IDS) and persistent depressive symptoms (PDS) using longitudinal data from South Africa.

METHODS

This longitudinal community study enrolled 3891 adults (≥40 years) from the "Health and Ageing in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI)". Sleep duration was assessed by self-report at wave 1, and depressive symptoms were assessed using the Center for Epidemiological Studies Depression Scale at wave 1 and 2. Outcomes were incident and persistent depressive symptoms at wave 2. Multivariable logistic regression analysis was conducted to assess the associations between sleep duration at wave 1 and incident, and persistent depressive symptoms.

RESULTS

The prevalence of IDS was 25.6% and PDS 30.8%. The prevalence of very short, short, normal, and long sleep duration at baseline was 3.6%, 10.1%, 60.9% and 25.4%, respectively. In the fully adjusted model, long sleep duration was positively associated with IDS among men (AOR: 1.37, 95% CI: 1.02-1.84), but not among women (AOR: 0.91, 95% CI: 0.67-1.23). No models among both men and women showed a significant association between short sleep and IDS. Long sleep duration was associated with PDS (AOR: 2.04, 95% CI: 1.20-3.48) among men but not among women (AOR: 1.26, 95% CI: 0.76-2.11). Short sleep showed among both sexes no significant associations with PDS.

CONCLUSION

Long but not short sleep duration was independently associated with IDS and PDS among men but not among women.

Metal ions in cerebrospinal fluid: Associations with anxiety, depression, and insomnia among cigarette smokers

OBJECTIVE

The study aimed to investigate the relationship between cerebrospinal fluid (CSF) metal ions and anxiety, depression, and insomnia among cigarette smokers.

METHODS

We measured CSF levels of various metal ions from 178 Chinese male subjects. Apart from sociodemographic and clinical characteristics data, the Fagerstrom Test for Nicotine Dependence (FTND), Beck Depression Inventory (BDI), Self-Rating Anxiety Scale (SAS), and Pittsburgh Sleep Quality Index (PSQI) were applied.

RESULTS

BDI and PSQI scores (all p < 0.001) were significantly higher in active smokers than nonsmokers. Active smokers have significantly higher CSF levels of magnesium, zinc, iron, lead, lithium, and aluminum (all p ≤ 0.002). Some metal ions, including zinc, iron, lead, and aluminum, were found to have a significant correlation with BDI scores, whereas metal ions, including zinc and lead, were found to have a significant correlation with PSQI scores in the general group. More interesting, mediation analysis showed that aluminum mediated the relationship between smoking and depression.

CONCLUSIONS

Cigarette smoking was indeed associated with depression and insomnia. Active smokers had significantly higher CSF levels of magnesium, zinc, iron, lead, lithium, and aluminum. Furthermore, CSF aluminum played a mediating role in the relationship between smoking and depression, which further confirmed its neurotoxicity.

Impact of Sleep Duration on Decline in Kidney Function in Adult Patients with Hypertension: A Community-Based Prospective Cohort Study

Background

Sleep duration is associated with various health conditions, including chronic kidney disease. However, the association between sleep duration and decline in kidney function in the South Korean population remains unclear. We aimed to investigate the impact of sleep duration on kidney function decline in adult patients with hypertension.

Methods

This cohort study was performed using data obtained from the Korean Genome and Epidemiology Study; 2,837 patients with hypertension who initially had normal kidney function were included. Glomerular filtration rates (GFRs) were estimated at baseline and throughout the 16 years of follow-up. A person was considered to have a decline in kidney function if they had a GFR <60 mL/min/1.73 m². Sleep duration data were obtained through interviewer-assisted questionnaires. Sleep durations were classified as short (<6 hours), normal (≥6 hours but <9 hours), and long (≥9 hours). The Cox proportional hazards model was applied, with adjustments for covariates.

Results

After adjusting for covariates, sleep duration was not associated with a decline in kidney function. However, among men with poorly controlled hypertension at baseline, compared to men with normal sleep durations, men with sleep durations <6 hours had a significantly higher risk of kidney function decline (hazard ratio, 1.56; 95% confidence interval, 1.02–2.36).

Conclusion

Short sleep duration did not seem to be associated with an increased risk of decline in kidney function; however, it may be a risk factor for the decline in kidney function in men with poorly controlled hypertension.

Prospective association between sleep duration and cognitive impairment: Findings from the China Health and Retirement Longitudinal Study (CHARLS)

Objective

The association between sleep duration and cognition are inconclusive. Our study aimed to comprehensively investigate the effects of sleep duration on the risk of cognitive impairment in the middle-aged and older Chinese population.

Methods

We used the longitudinal cohort data from waves 1–4 (2011–2018) of the China Health and Retirement Longitudinal Study (CHARLS). Self-reported exposures included total sleep duration, nocturnal sleep duration, post-lunch napping, and changes in sleep duration over time according to face-to-face interviews. Cognitive function was assessed by a Chinese version of the Modified Mini-Mental State Examination (MMSE).

Results

A total of 7,342 eligible participants were included. The mean age was 61.5 ± 6.5 years, and 48.9% (3,588/7,342) were male. We identified a U-shaped association of total sleep duration as well as nocturnal sleep duration with the risk of cognitive impairment. People with 7–8 h of total sleep duration and 6–7 h of nocturnal sleep had the lowest risk of cognitive impairment. Further results showed that post-lunch napping within 2 h was beneficial to cognition and 60 min was optimal. Moreover, analyses of changes in sleep duration further supported that sleeping less or more was harmful to cognition. Notably, those “excessive-change” sleepers (from ≤6 to ≥9 h, or from ≥9 to ≤6 h) had more risks.

Conclusions

Keeping 7–8 h per day was related to the lowest risk of cognitive impairment in midlife and late life, and an optimal post-lunch napping was 60 min for these stable sleepers. Especially, excessive changes in sleep duration over time led to poorer cognition. Our work highlights the importance of optimal sleep habits to cognitive function. The self-reported sleep measures limited our findings, and further studies are needed for verification.

Potential Role of Sleep Deficiency in Inducing Immune Dysfunction

Sleep deficiency and insomnia deteriorate the quality of patients’ lives, yet the exact influence of these factors on the immune system has only begun to gain interest in recent years. Growing evidence shows that insomnia is a risk factor for numerous diseases, including common infections and autoimmune diseases. Levels of inflammatory markers also seem to be abnormal in sleep deficient individuals, which may lead to low-grade inflammation. The interpretation of studies is difficult due to the equivocal term “sleep disturbances,” as well as due to the various criteria used in studies. This narrative review aims to summarize the available knowledge regarding the bidirectional influence of the immune system and sleep disturbances.

Sleep disruption induces activation of inflammation and heightens risk for infectious disease: Role of impairments in thermoregulation and elevated ambient temperature

Thermoregulation and sleep are tightly coordinated, with evidence that impairments in thermoregulation as well as increases in ambient temperature increase the risk of sleep disturbance. As a period of rest and low demand for metabolic resources, sleep functions to support host responses to prior immunological challenges. In addition by priming the innate immune response, sleep prepares the body for injury or infection which might occur the following day. However when sleep is disrupted, this phasic organization between nocturnal sleep and the immune system becomes misaligned, cellular and genomic markers of inflammation are activated, and increases of proinflammatory cytokines shift from the nighttime to the day. Moreover, when sleep disturbance is perpetuated due to thermal factors such as elevated ambient temperature, the beneficial crosstalk between sleep and immune system becomes further imbalanced. Elevations in proinflammatory cytokines have reciprocal effects and induce sleep fragmentation with decreases in sleep efficiency, decreases in deep sleep, and increases in rapid eye movement sleep, further fomenting inflammation and inflammatory disease risk. Under these conditions, sleep disturbance has additional potent effects to decrease adaptive immune response, impair vaccine responses, and increase vulnerability to infectious disease. Behavioral interventions effectively treat insomnia and reverse systemic and cellular inflammation. Further, insomnia treatment redirects the misaligned inflammatory- and adaptive immune transcriptional profiles with the potential to mitigate risk of inflammation-related cardiovascular, neurodegenerative, and mental health diseases, as well as susceptibility to infectious disease.

Microglia Are Necessary to Regulate Sleep after an Immune Challenge

Microglia play a critical role in the neuroimmune response, but little is known about the role of microglia in sleep following an inflammatory trigger. Nevertheless, decades of research have been predicated on the assumption that an inflammatory trigger increases sleep through microglial activation. We hypothesized that mice (n = 30) with depleted microglia using PLX5622 (PLX) would sleep less following the administration of lipopolysaccharide (LPS) to induce inflammation. Brains were collected and microglial morphology was assessed using quantitative skeletal analyses and physiological parameters were recorded using non-invasive piezoelectric cages. Mice fed PLX diet had a transient increase in sleep that dissipated by week 2. Subsequently, following a first LPS injection (0.4 mg/kg), mice with depleted microglia slept more than mice on the control diet. All mice were returned to normal rodent chow to repopulate microglia in the PLX group (10 days). Nominal differences in sleep existed during the microglia repopulation period. However, following a second LPS injection, mice with repopulated microglia slept similarly to control mice during the dark period but with longer bouts during the light period. Comparing sleep after the first LPS injection to sleep after the second LPS injection, controls exhibited temporal changes in sleep patterns but no change in cumulative minutes slept, whereas cumulative sleep in mice with repopulated microglia decreased during the dark period across all days. Repopulated microglia had a reactive morphology. We conclude that microglia are necessary to regulate sleep after an immune challenge.

Potential Psychoactive Effects of Microalgal Bioactive Compounds for the Case of Sleep and Mood Regulation: Opportunities and Challenges

Sleep deficiency is now considered an emerging global epidemic associated with many serious health problems, and a major cause of financial and social burdens. Sleep and mental health are closely connected, further exacerbating the negative impact of sleep deficiency on overall health and well-being. A major drawback of conventional treatments is the wide range of undesirable side-effects typically associated with benzodiazepines and antidepressants, which can be more debilitating than the initial disorder. It is therefore valuable to explore the efficiency of other remedies for complementarity and synergism with existing conventional treatments, leading to possible reduction in undesirable side-effects. This review explores the relevance of microalgae bioactives as a sustainable source of valuable phytochemicals that can contribute positively to mood and sleep disorders. Microalgae species producing these compounds are also catalogued, thus creating a useful reference of the state of the art for further exploration of this proposed approach. While we highlight possibilities awaiting investigation, we also identify the associated issues, including minimum dose for therapeutic effect, bioavailability, possible interactions with conventional treatments and the ability to cross the blood brain barrier. We conclude that physical and biological functionalization of microalgae bioactives can have potential in overcoming some of these challenges.

Sleep duration and risk of cancer incidence and mortality: a pooled analysis of six population-based cohorts in Japan

Sleep duration is emerging as an important modifiable risk factor for morbidity and mortality. We assessed the association between sleep duration and cancer incidence and mortality among Japanese adults using data from six population-based cohorts with 271 694 participants. During a total follow-up period of about 5.9 million person-years, we identified 40 751 incident cancer cases and 18 323 cancer deaths. We computed study-specific hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox proportional hazards regression models and pooled the estimates using random-effects meta-analysis. Sleep duration of ≥ 10 h (vs. 7 h) was associated with increased risk of cancer incidence among women (HR 1.19, 95% CI 1.02-1.38), but not men, and increased risk of cancer mortality among men (HR 1.18, 95% CI 1.00-1.39) and women (HR 1.44, 95% CI 1.20-1.73). Sleep duration of ≤ 5 h (vs. 7 h) was not associated with cancer incidence and mortality. However, among post-menopausal women, sleep durations of both ≤ 5 h and ≥ 10 h (vs. 7 h) were associated with an increased risk of cancer mortality. Among Japanese adults, sleep duration of ≥ 10 h is associated with increased risk of cancer incidence and mortality among women and cancer mortality among men. This article is protected by copyright. All rights reserved.

Modifiable predictive factors and all-cause mortality in the non-hospitalized elderly population: An umbrella review of meta-analyses

OBJECTIVE

This umbrella review aimed to summarize the association between modifiable predictive factors and all-cause mortality in the non-hospitalized elderly population, and estimated the credibility and strength of the current evidence.

METHODS

PubMed, Embase, Web of science, and EBSCOhost were searched up to February 28, 2022. Random-effect summary effect sizes and 95% confidence intervals (CIs), heterogeneity, small-study effect, excess significance bias, as well as 95% prediction intervals (PIs) were calculated. Methodological quality was assessed with the Assessment of Multiple Systematic Reviews 2 (AMSTAR-2) tool. The credibility of the included meta-analyses was graded from convincing to weak using established criteria. This umbrella review was registered with PROSPERO, CRD 42021282183.

RESULTS

In total, 32 predictive factors involving 49 associations extracted from 35 meta-analyses were analyzed. Forty-three of the 49 (87.8%) associations presented nominal significant effects by the random-effect model (P < 0.05), of which 34 had harmful associations and nine had beneficial associations with all-cause mortality. Frailty (FRAIL scale), low short physical performance battery (SPPB) score, and fewer daily steps carried a more than three-fold risk for all-cause mortality. Convincing evidence showed that weight fluctuation, prefrailty and frailty status, sarcopenia, low SPPB score, fewer daily steps, and fatigue increased the risk of all-cause mortality, while daily moderate-to-vigorous physical activity (MVPA) duration and total physical activity participation reduced the risk of death. There were twenty, nine, five, and six associations that yielded highly suggestive, suggestive, weak, and non-significant grades of evidence. Thirty-four (69.4%) of the associations exhibited significant heterogeneity. Twenty-two associations presented 95% PIs excluding the null value, two indicated small-study effects, and three had evidence for excess significance bias, respectively. The methodological quality of most meta-analyses was rated as low (37.1%) or critically low (42.9%).

CONCLUSIONS

A summary of the currently available meta-analyses suggests that a broad range of modifiable predictive factors are significantly associated with all-cause mortality risk in the non-hospitalized elderly population. The most credible evidence indicates that physical function represented by frailty and sarcopenia, as well as physical activity, are significant predictors for all-cause mortality. This umbrella review may provide prognostic information to direct appropriate diagnostic evaluation and treatment goals in the future. More solid evidence is still needed coming from moderate-to-high quality meta-analyses.

Differential effects of an experimental model of prolonged sleep disturbance on inflammation in healthy females and males

Sleep disturbances, including disrupted sleep and short sleep duration, are highly prevalent and are prospectively associated with an increased risk for various widespread diseases, including cardiometabolic, neurodegenerative, chronic pain, and autoimmune diseases. Systemic inflammation, which has been observed in populations experiencing sleep disturbances, may mechanistically link disturbed sleep with increased disease risks. To determine whether sleep disturbances are causally responsible for the inflammatory changes reported in population-based studies, we developed a 19-day in-hospital experimental model of prolonged sleep disturbance inducing disrupted and shortened sleep. The model included delayed sleep onset, frequent nighttime awakenings, and advanced sleep offset, interspersed with intermittent nights of undisturbed sleep. This pattern aimed at providing an ecologically highly valid experimental model of the typical sleep disturbances often reported in the general and patient populations. Unexpectedly, the experimental sleep disturbance model reduced several of the assessed proinflammatory markers, namely interleukin(IL)-6 production by monocytes and plasma levels of IL-6 and C-reactive protein (CRP), presumably due to intermittent increases in the counterinflammatory hormone cortisol. Striking sex differences were observed with females presenting a reduction in proinflammatory markers and males showing a predominantly proinflammatory response and reductions of cortisol levels. Our findings indicate that sleep disturbances causally dysregulate inflammatory pathways, with opposing effects in females and males. These results have the potential to advance our mechanistic understanding of the pronounced sexual dimorphism in the many diseases for which sleep disturbances are a risk factor.

Sleep Duration/Quality With Health Outcomes: An Umbrella Review of Meta-Analyses of Prospective Studies

Background

To quantitatively evaluate the evidence of duration and quality of sleep as measured by multiple health outcomes.

Methods

This review is registered with PROSPERO, number CRD42021235587. We systematically searched three databases from inception until November 15, 2020. For each meta-analysis, the summary effect size using fixed and random effects models, the 95% confidence interval, and the 95% prediction interval were assessed; heterogeneity, evidence of small-study effects, and excess significance bias were also estimated. According to the above metrics, we evaluated the credibility of each association.

Results

A total of 85 meta-analyses with 36 health outcomes were included in the study. We observed highly suggestive evidence for an association between long sleep and an increased risk of all-cause mortality. Moreover, suggestive evidence supported the associations between long sleep and 5 increased risk of health outcomes (stroke, dyslipidaemia, mortality of coronary heart disease, stroke mortality, and the development or death of stroke); short sleep and increased risk of overweight and/or obesity; poor sleep quality and increased risk of diabetes mellitus and gestational diabetes mellitus.

Conclusions

Only the evidence of the association of long sleep with an increased risk of all-cause mortality was graded as highly suggestive. Additional studies are needed to be conducted.

Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42021235587

Immune targets for therapeutic development in depression: towards precision medicine

Over the past two decades, compelling evidence has emerged indicating that immune mechanisms can contribute to the pathogenesis of major depressive disorder (MDD) and that drugs with primary immune targets can improve depressive symptoms. Patients with MDD are heterogeneous with respect to symptoms, treatment responses and biological correlates. Defining a narrower patient group based on biology could increase the treatment response rates in certain subgroups: a major advance in clinical psychiatry. For example, patients with MDD and elevated pro-inflammatory biomarkers are less likely to respond to conventional antidepressant drugs, but novel immune-based therapeutics could potentially address their unmet clinical needs. This article outlines a framework for developing drugs targeting a novel patient subtype within MDD and reviews the current state of neuroimmune drug development for mood disorders. We discuss evidence for a causal role of immune mechanisms in the pathogenesis of depression, together with targets under investigation in randomized controlled trials, biomarker evidence elucidating the link to neural mechanisms, biological and phenotypic patient selection strategies, and the unmet clinical need among patients with MDD.

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.

Oral contraceptives, depressive and insomnia symptoms in adult women with and without depression

BACKGROUND

Worldwide, oral contraceptive (OC) use is a very common form of birth control, although it has been associated with symptoms of depression and insomnia. Insomnia is a risk factor for major depressive disorder (MDD) but may also be a symptom of the disorder. Despite the large number of women who use OC, it is yet unknown whether women with previous or current diagnosis of depression are more likely to experience more severe depressive and insomnia symptoms during concurrent OC use than women without diagnosis of depression.

AIM

This study examined associations between OC use and concurrent symptoms of depression (including atypical depression) and insomnia as well as between OC and prevalences of concurrent dysthymia and MDD. Participants were adult women with and without a history of MDD or dysthymia. We hypothesized that OC use is associated with concurrent increased severity of depressive symptoms and insomnia symptoms, as well as with an increased prevalence of concurrent diagnoses of dysthymia and MDD. We also hypothesized that a history of MDD or dysthymia moderates the relationship between OC use and depressive and insomnia symptoms.

METHODS

Measurements from premenopausal adult women from the Netherlands Study of Depression and Anxiety (NESDA) were grouped, based on whether participants were using OC or naturally cycling (NC). OC use, timing and regularity of the menstrual cycle were assessed with a structured interview, self-reported symptoms of depression (including atypical depression), insomnia with validated questionnaires, and MDD and dysthymia with structured diagnostic interviews.

RESULTS

We included a total of 1301 measurements in women who reported OC use and 1913 measurements in NC women (mean age 35.6, 49.8% and 28.9% of measurements in women with a previous depression or current depression, respectively). Linear mixed models showed that overall, OC use was neither associated with more severe depressive symptoms (including atypical depressive symptoms), nor with higher prevalence of diagnoses of MDD or dysthymia. However, by disentangling the amalgamated overall effect, within-person estimates indicated increased depressive symptoms and depressive disorder prevalence during OC use, whereas between-person estimated indicated lower depressive symptoms and prevalence of depressive disorders. OC use was consistently associated with more severe concurrent insomnia symptoms, in the overall estimates as well as in the within-person and between-person estimates. Presence of current or previous MDD or dysthymia did not moderate the associations between OC use and depressive or insomnia symptoms.

DISCUSSION

The study findings showed consistent associations between OC use and more severe insomnia symptoms, but no consistent associations between OC and depressive symptoms or diagnoses. Instead, post-hoc analyses showed that associations between OC and depression differed between within- and between person-estimates. This indicates that, although OC shows no associations on the overall level, some individuals might experience OC-associated mood symptoms. Our findings underscore the importance of accounting for individual differences in experiences during OC use. Furthermore, it raises new questions about mechanisms underlying associations between OC, depression and insomnia.

Suicidal ideation and suicide attempts: associations with sleep duration, insomnia, and inflammation

BACKGROUND

Sleep disturbance has been consistently identified as an independent contributor to suicide risk. Inflammation has emerged as a potential mechanism linked to both sleep disturbance and suicide risk. This study tested associations between sleep duration, insomnia, and inflammation on suicidal ideation (SI) and history of a suicide attempt (SA).

METHODS

Participants included 2329 adults with current or remitted depression and/or anxiety enrolled in the Netherlands Study of Depression and Anxiety. Sleep duration, insomnia, past week SI, and SA were assessed with self-report measures. Plasma levels of C-reactive protein, interleukin-6, and tumor necrosis factor-α were obtained.

RESULTS

Short sleep duration (⩽6 h) compared to normal sleep duration (7-9 h) was associated with reporting a prior SA, adjusting for covariates [adjusted odds ratio (AOR) 1.68, 95% CI 1.13-2.51]. A higher likelihood of SI during the past week was observed for participants with long sleep duration (⩾10 h) compared to normal sleep duration (AOR 2.22, 95% CI 1.02-4.82), more insomnia symptoms (AOR 1.44, 95% CI 1.14-1.83), and higher IL-6 (AOR 1.31, 95% CI 1.02-1.68). Mediation analyses indicated that the association between long sleep duration and SI was partially explained by IL-6 (AOR 1.02, 95% CI 1.00-1.05).

CONCLUSIONS

These findings from a large sample of adults with depression and/or anxiety provide evidence that both short and long sleep duration, insomnia symptoms, and IL-6 are associated with the indicators of suicide risk. Furthermore, the association between long sleep duration and SI may operate through IL-6.

Black-White racial health disparities in inflammation and physical health: Cumulative stress, social isolation, and health behaviors

Black Americans have vastly increased odds and earlier onsets of stress- and age-related disease compared to White Americans. However, what contributes to these racial health disparities remains poorly understood. Using a sample of 1577 older adults (32.7% Black; ages 55-65 at baseline), we examined whether stress, health behaviors, social isolation, and inflammation are associated with racial disparities in self-reported physical health. A latent cumulative stress factor and unique stress-domain specific factors were modeled by applying bifactor confirmatory analysis to assessments across the lifespan (i.e., childhood maltreatment, trauma exposure, discrimination, stressful life events, and indices of socioeconomic status). Physical health, health behavior, and social isolation were assessed using self-report. Interleukin-6 (IL-6) and C-reactive protein (CRP) were assayed from morning fasting serum samples; a z-scored inflammation index was formed across these 2 cytokines. A parallel serial mediational model tested whether race (i.e., Black/White) is indirectly associated with health through the following 3 independent pathways: (1) cumulative stress to preventative health behaviors (e.g., healthy eating) to inflammation, (2) cumulative stress to risky health behaviors (e.g., substance use) to inflammation; and (3) cumulative stress to social isolation to inflammation. There were significant indirect effects between race and self-reported physical health through cumulative stress, preventative health behaviors, and inflammation (B = -0.02, 95% CI: -0.05, -0.01). Specifically, Black Americans were exposed to greater cumulative stress, which was associated with reduced engagement in preventative health behaviors, which was, in turn, associated with greater inflammation and reduced physical health. A unique SES factor also indirectly linked race to physical health through preventative health behaviors. Cumulative stress exposure and unique aspects of socioeconomic status are indirectly associated with Black-White racial health disparities through behavioral (i.e., preventative health behavior) and biological (i.e., inflammation) factors. Culturally responsive evidence-based interventions that enhance engagement in preventative health behaviors are needed to directly confront health disparities. Ultimately, large scale anti-racist public policies that reduce cumulative stress burden (e.g., a living wage, universal healthcare) may best attenuate racial health disparities.

Sleep duration and health outcomes: an umbrella review

PURPOSE

To collect existing evidence on the relationship between sleep duration and health outcomes.

METHODS

A thorough search was conducted in PubMed, Web of Science, Embase, and the Cochrane Database of Systematic Reviews from inception to January, 2021. Meta-analyses of observational and interventional studies were eligible if they examined the associations between sleep duration and human health.

RESULTS

In total, this umbrella review identified 69 meta-analyses with 11 outcomes for cancers and 30 outcomes for non-cancer conditions. Inappropriate sleep durations may significantly elevate the risk for cardiovascular disease (CVD), cognitive decline, coronary heart disease (CHD), depression, falls, frailty, lung cancer, metabolic syndrome (MS), and stroke. Dose-response analysis revealed that a 1-h reduction per 24 hours is associated with an increased risk by 3-11% of all-cause mortality, CHD, osteoporosis, stroke, and T2DM among short sleepers. Conversely, a 1-h increment in long sleepers is associated with a 7-17% higher risk of stroke mortality, CHD, stroke, and T2DM in adults.

CONCLUSION

Inappropriate sleep duration is a risk factor for developing non-cancer conditions. Decreasing and increasing sleep hours towards extreme sleep durations are associated with poor health outcomes.

Depressive and anxiety disorders in concert-A synthesis of findings on comorbidity in the NESDA study

BACKGROUND

Comorbidity of depressive and anxiety disorders is common and remains incompletely comprehended. This paper summarizes findings from the Netherlands Study of Depression and Anxiety (NESDA) regarding prevalence, temporal sequence, course and longitudinal patterns; sociodemographic, vulnerability and neurobiological indicators; and functional, somatic and mental health indicators of comorbidity.

METHODS

Narrative synthesis of earlier NESDA based papers on comorbidity (n=76).

RESULTS

Comorbidity was the rule in over three-quarter of subjects with depressive and/or anxiety disorders, most often preceded by an anxiety disorder. Higher severity and chronicity characterized a poorer comorbidity course. Over time, transitions between depressive and anxiety disorders were common. Consistent comorbidity risk indicators in subjects with depressive and anxiety disorders were childhood trauma, neuroticism and early age of onset. Psychological vulnerabilities, such as trait avoidance tendencies, were more pronounced in comorbid than in single disorders. In general, there were few differences in biological markers and neuroimaging findings between persons with comorbid versus single disorders. Most functional, somatic, and other mental health indicators, ranging from disability to cardiovascular and psychiatric multimorbidity, were highest in comorbid disorders.

LIMITATIONS

The observational design of NESDA limits causal inference. Attrition was higher in comorbid relative to single disorders.

CONCLUSIONS

As compared to single disorders, persons with comorbid depressive and anxiety disorders were characterized by more psychosocial risk determinants, more somatic and other psychiatric morbidities, more functional impairments, and poorer outcome. These results justify specific attention for comorbidity of depressive and anxiety disorders, particularly in treatment settings.

Sleep duration is related to increased mortality risk through white blood cell counts in a large national sample

OBJECTIVES

Sleep, like many biological processes, is linked with immunity and inflammation such that "abnormal" sleep is associated with changes in circulating immune cells. These sleep patterns are also associated with increased mortality risk, and it may be that altered immune cell counts are one biological pathway through which sleep affects mortality. We used NHANES survey data to examine the associations between sleep duration, total white blood cell (WBC) count, and mortality from biological causes.

METHODS

Several waves of public NHANES data (2005-2011; n = 11 353, ages 18+) were analyzed using bivariate statistics and causal mediation models including corrections for complex survey design.

RESULTS

Deceased individuals were characterized by higher WBC but lower monocyte counts relative to surviving individuals. Significant associations between sleep duration, total WBC count, monocytes and mortality were found, as were marginally significant relationships between sleep and these cell counts. Significant mediated effects of sleep on mortality were found. Including covariates known to affect mortality, such as BMI, age, and self-reported health resulted in a nonsignificant mediated effect of sleep on mortality for monocytes, while mediated effects for total WBC count remained.

CONCLUSIONS

This large, cross-sectional analysis suggests that sleep duration is associated with changes in mortality risk through-in part-effects on leukocyte count. These findings support an immunological/inflammatory pathway linking sleep and mortality. Further research in populations with quantitatively different sleep patterns can determine whether this sleep-immune-mortality pathway is restricted to Western, industrial samples or is characteristic of humans in general.

The Association Between Sleep and Metabolic Syndrome: A Systematic Review and Meta-Analysis

PURPOSE

Sleep duration is thought to play a key role in the development of metabolic syndrome. However, the results have been inconsistent.

METHODS

We conducted a systematic review and meta-analysis of cohort studies and searched publications in PubMed, Embase, Cochrane Central Register of Controlled Trials, and Clinicaltrials.gov. The summary relative risks (RRs) were estimated using a random model. The sensitivity analysis was performed by sequentially excluding each study to test the robustness of the pooled estimates.

FINDING

We included 13 studies involving 300,202 patients in which short sleep and long sleep significantly increased the risk of metabolic syndrome 15% (RR = 1.15, 95%CI = 1.09-1.22, p < 0.001) and 19% (RR = 1.19, 95%CI = 1.05-1.35, p < 0.001). Moreover, the relationship between sleep duration and metabolic syndrome risk presented a U-shaped curve. Short and long sleep increased the risk of obesity by 14% (RR = 1.14, 95%CI = 1.07-1.22, p<0.001) and 15% (RR = 1.15, 95%CI = 1.00-1.30, p = 0.04), and high blood pressure 16% (RR = 1.16, 95%CI = 1.02-1.31, p = 0.03) and 13% (RR = 1.13, 95%CI = 1.04-1.24, p = 0.01), respectively. Short sleep can potentially increase the risk of high blood sugar by 12% (RR = 1.12, 95%CI = 1.00-1.15, P = 0.05).

IMPLICATIONS

Based on our findings, sleep is a behavior that can be changed and is economical. Clinically doctors and health professionals should be encouraged to increase their efforts to promote healthy sleep for all people.

The association of occupational stress and sleep duration with anxiety symptoms among healthy employees: A cohort study

The aim of this study is to identify occupational stress associated with the development of new-onset anxiety symptoms and the dose-response relationship between sleep duration and the onset of anxiety symptoms. Data from 29,251 healthy employees who had undergone at least two comprehensive health examinations at Kangbuk Samsung Hospital Health Screening Center were analysed. Anxiety symptoms were assessed using the Beck Anxiety Inventory. Occupational stress and sleep duration were measured using a self-reported questionnaire about total sleep time and the Korean Occupational Stress Scale-Short Form (KOSS-SF), respectively. Flexible parametric proportional hazards model used to estimate the hazard ratios. Compared with the groups without case-level anxiety, discomfort in an organizational climate, high job demands, job insecurity, organizational injustice and lack of reward were associated with the onset of case-level anxiety. Compared with less than 6 hr of sleep per day, the beneficial level of sleep duration was 7 ≤ to <9 hr a day. Almost all subscales of job stress were associated with the development of anxiety symptoms. In addition, the efficacious level of sleep duration for reducing the onset of future anxiety symptoms was 7 ≤ to <9 hr a day.

The effect of insomnia on development of Alzheimer's disease

Alzheimer's disease (AD) is the most common type of dementia and a neurodegenerative disorder characterized by memory deficits especially forgetting recent information, recall ability impairment, and loss of time tracking, problem-solving, language, and recognition difficulties. AD is also a globally important health issue but despite all scientific efforts, the treatment of AD is still a challenge. Sleep has important roles in learning and memory consolidation. Studies have shown that sleep deprivation (SD) and insomnia are associated with the pathogenesis of Alzheimer's disease and may have an impact on the symptoms and development. Thus, sleep disorders have decisive effects on AD; this association deserves more attention in research, diagnostics, and treatment, and knowing this relation also can help to prevent AD through screening and proper management of sleep disorders. This study aimed to show the potential role of SD and insomnia in the pathogenesis and progression of AD.

Getting under the skin: Does biology help predict chronicity of depression?

BACKGROUND

Depressed patients are at risk of an unfavourable course including chronic episodes. Various psychiatric characteristics have shown to be predictive of depression's course trajectory, but whether indicators of somatic health further contribute to course prediction remains unclear. This study aimed to identify somatic health indicators (i.e. biomarkers, health status and lifestyle) that predict 2-year chronicity above and beyond an extensive list of sociodemographic and psychiatric characteristics.

METHODS

Data are from patients with current depression at baseline (n = 903) and available 2-year follow-up participating in a longitudinal cohort study. Baseline demographic, psychiatric and somatic health indicators were associated with 2-year course trajectories, classified as non-chronic versus chronic RESULTS: At 2-year follow up, 40% of the patients showed a chronic course. Of the twenty tested somatic health indicators, short sleep and high interleukin-6 improved the regression model predicting chronicity with a significant, but modest, effect (ROC = 0.78; p = 0.03).

LIMITATIONS

Due to the observational design we did not have the ability to reliably consider the impact of psychiatric treatment. More elaborate information on somatic health such as dietary patterns would strengthen the study.

CONCLUSIONS

This study showed that short sleep duration and high interleukin-6 contributed significantly to the regression model as independent predictors, suggestive of clinical implications for patients with sleep disturbances and elevated inflammation levels. Other somatic health indicators did not add to the model. Overall, somatic health indicators showed modest additive value for predicting chronic course above and beyond sociodemographic and psychiatric indicators.