Sleep deprivation and human immune function

Feasibility and acceptability for LION, a fully remote, randomized clinical trial within the VA for light therapy to improve sleep in Veterans with and without TBI: An MTBI2 sponsored protocol

Sleep-wake disturbances frequently present in Veterans with mild traumatic brain injury (mTBI). These TBI-related sleep impairments confer significant burden and commonly exacerbate other functional impairments. Therapies to improve sleep following mTBI are limited and studies in Veterans are even more scarce. In our previous pilot work, morning bright light therapy (MBLT) was found to be a feasible behavioral sleep intervention in Veterans with a history of mTBI; however, this was single-arm, open-label, and non-randomized, and therefore was not intended to establish efficacy. The present study, LION (light vs ion therapy) extends this preliminary work as a fully powered, sham-controlled, participant-masked randomized controlled trial (NCT03968874), implemented as fully remote within the VA (target n = 120 complete). Randomization at 2:1 allocation ratio to: 1) active: MBLT (n = 80), and 2) sham: deactivated negative ion generator (n = 40); each with identical engagement parameters (60-min duration; within 2-hrs of waking; daily over 28-day duration). Participant masking via deception balanced expectancy assumptions across arms. Outcome measures were assessed following a 14-day baseline (pre-intervention), following 28-days of device engagement (post-intervention), and 28-days after the post-intervention assessment (follow-up). Primary outcomes were sleep measures, including continuous wrist-based actigraphy, self-report, and daily sleep dairy entries. Secondary/exploratory outcomes included cognition, mood, quality of life, circadian rhythm via dim light melatonin onset, and biofluid-based biomarkers. Participant drop out occurred in <10% of those enrolled, incomplete/missing data was present in <15% of key outcome variables, and overall fidelity adherence to the intervention was >85%, collectively establishing feasibility and acceptability for MBLT in Veterans with mTBI.

Human sleep and immunity: The role of circadian patterns

It is well established that sleep promotes health and welfare. Literature data suggests that sleep is a recurrent resting state that performs multiple biological functions, such as memory consolidation and regulation of glucose, lipid metabolism, energy metabolism, eating behavior, and blood pressure, besides, regulating the immune system. These immunological functions depend on regular sleep and circadian rhythms, as both impact the magnitude of immune responses. Circadian rhythm is the 24-h internal clock in our brain that regulates cycles of alertness and sleepiness by responding to light changes in our environment. It encompasses physical and behavioral daily oscillations. Sleep deprivation and circadian misalignment affect immunity, and both have been related to adverse health effects and chronic diseases. Studies have shown that individuals with regular and consistent sleep patterns have a more effective immune response. Thus, understanding how sleep disturbance will affect the immune response is vital in developing interventions to prevent the health burden of irregular sleep patterns and circadian misalignment, favoring a homeostatic immune defense to microbial or inflammatory insults. Therefore, the scope of this chapter is to explore evidence that regular circadian rhythms and sleep patterns are needed for optimal resistance to infectious challenges.

Coming out of isolation: impacts of COVID-19 on physical activity, diet, mental well-being, and sleep over time

Introduction

The COVID-19 pandemic lockdown significantly disrupted daily routines and impacted physical activity, diet, mental well-being, and sleep. This mixed-methods study investigates these changes over three periods-pre-pandemic, pandemic onset, and one-year post-onset-to understand their causes and inform public health policy for improved resilience during future crises.

Methods

A mixed-methods study was conducted with 34 US participants who completed open-ended qualitative questions and quantitative assessments in May 2020 and May 2021. Participants were recruited via social media from 10 states with high COVID-19 cases. Quantitative data categorized health changes (positive, negative, or no change), while qualitative data were analyzed thematically to explore reasons for these changes and uncover interrelationships among health behaviors.

Results

Quantitative results showed that, during the pandemic onset, most participants experienced negative changes in diet, mental well-being, and sleep, while physical activity varied. By one-year post-onset, improvements were noted across all health pillars, with mental well-being and sleep showing the most significant positive changes. Thematic analysis of qualitative data revealed stress, anxiety, and personal motivations as key drivers of health behaviors. Participants' narratives provided a deeper understanding of these shifts that a Likert-style survey alone could not capture, highlighting the interconnectedness of health pillars.

Discussion

The findings demonstrate the importance of addressing mental well-being to improve overall health resilience. Public health interventions should prioritize mental health and consider the interrelated nature of health behaviors. The mixed-methods approach combined quantitative trends with qualitative insights, offering a comprehensive understanding of why health changes occurred, providing actionable guidance for future public health policy.

Sleep patterns and their associations with psychiatric symptoms among Chinese healthcare workers: a latent profile analysis

Background

Healthcare workers often encounter inadequate sleep conditions. However, limited research has examined the underlying sleep patterns among healthcare workers. This study aimed to identify sleep patterns in healthcare workers, explore predictors associated with various sleep patterns, and investigate the relationship between sleep patterns and psychiatric symptoms.

Methods

This cross-sectional study was conducted in Shenzhen, China, from April 2023 to June 2023. In total, data from 1,292 participants were included using a convenience sampling method. A latent profile analysis was conducted to identify sleep patterns based on the seven dimensions of the Pittsburgh Sleep Quality Index. Multinomial logistic regression analysis was conducted to investigate the influence of socio-demographic variables on each profile. A one-way ANOVA test was employed to examine the relationships between sleep patterns and psychiatric symptoms.

Results

Three distinct profiles were identified: good sleepers (63.9%), inefficient sleepers (30.3%), and poor sleepers (5.7%). Multinomial logistic regression analysis indicated that gender and marital status were predictors of various sleep patterns. The ANOVA revealed significant differences in psychiatric symptoms scores among the three sleep patterns; poor sleepers exhibited the highest levels of mental distress.

Conclusion

This study identified three distinct sleep patterns in healthcare workers and their significant associations with psychiatric symptoms. These findings contribute to the development of targeted intervention strategies aimed at improving sleep and reducing psychiatric symptoms among healthcare workers.

Sleep and neuroimmunology: a narrative review

Numerous neuroimmunological disorders present with sleep-related symptoms. The identification of novel autoantibodies introduces new clinical categories in autoimmune diseases of the central nervous system and generates interest in the dynamic interaction between sleep and the immune system. In this review, the complex relationship among sleep, immune regulation, and neuroimmunological disorders was examined with emphasis on the vital role of sleep in modulating immune function and its influence on these conditions, This relationship emphasizes the importance of assessments and management of sleep quality in the treatment approaches for neuroimmunological disorders.

Feasibility and acceptability for LION, a fully remote, randomized clinical trial within the VA for light therapy to improve sleep in Veterans with and without TBI: An MTBI2 sponsored protocol

Sleep-wake disturbances frequently present in Veterans with mild traumatic brain injury (mTBI). These TBI-related sleep impairments confer significant burden and commonly exacerbate other functional impairments. Therapies to improve sleep following mTBI are limited and studies in Veterans are even more scarce. In our previous pilot work, morning bright light therapy (MBLT) was found to be a feasible behavioral sleep intervention in Veterans with a history of mTBI; however, this was single-arm, open-label, and non-randomized, and therefore was not intended to establish efficacy. The present study, LION (light vs ion therapy) extends this preliminary work as a fully powered, sham-controlled, participant-masked randomized controlled trial (NCT03968874), implemented as fully remote within the VA (target n=120 complete). Randomization at 2:1 allocation ratio to: 1) active: MBLT (n=80), and 2) sham: deactivated negative ion generator (n=40); each with identical engagement parameters (60-min duration; within 2-hrs of waking; daily over 28-day duration). Participant masking via deception balanced expectancy assumptions across arms. Outcome measures were assessed following a 14-day baseline (pre-intervention), following 28-days of device engagement (post-intervention), and 28-days after the post-intervention assessment (follow-up). Primary outcomes were sleep measures, including continuous wrist-based actigraphy, self-report, and daily sleep dairy entries. Secondary/exploratory outcomes included cognition, mood, quality of life, circadian rhythm via dim light melatonin onset, and biofluid-based biomarkers. Participant drop out occurred in <10% of those enrolled, incomplete/missing data was present in <15% of key outcome variables, and overall fidelity adherence to the intervention was >85%, collectively establishing feasibility and acceptability for MBLT in Veterans with mTBI.

Association of sleep duration and risk of mental disorder: a systematic review and meta-analysis

BACKGROUND

The effects of sleep duration on the development of mental illness remain controversial. Therefore, it is necessary to identify the effects of long or short sleep duration on psychological disorders, which could reveal new ways for preventing and treating mental health conditions cheaply.

METHODS

Identifying published papers was accomplished by using the following five English databases on March 16, 2022: PubMed, MEDLINE, Embase, Web of Science databases, and Scopus. Cross-sectional and cohort studies were considered if they evaluated the association of sleep duration with all kinds of mental illness in adults. We excluded case reports, editorials, narrative reviews, and studies without detailed information on sleep duration. Summary effect-size estimates were expressed as risk ratios (RRs) or odds ratios (ORs) with 95% confidence intervals and were evaluated using random-effect models. Mantel-Haenszel's random-effects model was used to estimate the inconsistency index (I2) and Tau2 index (measurement of heterogeneity).

RESULTS

A total of 52 studies were included in this analysis, consisting of 14 cohort studies and 38 cross-sectional studies. These studies involved a combined sample size of 1,407,891 participants who met the inclusion criteria. Cohort (adjusted RR = 1.42, 95% CI: 1.26-1.60, P < .001, I2 = 37.6%, Tau2 = 0.014) and cross-sectional studies (adjusted OR = 1.67, 95% CI: 1.57-1.77, P < .001, I2 = 79.7%, Tau2 = 0.060) concluded that short sleep duration increased mental disorder risks. The same conclusions were acquired in the subgroup analysis, especially for depression (adjusted RR = 1.43, 95% CI: 1.24-1.65, P < .001, I2 = 80.4%, Tau2 = 0.082), anxiety (adjusted RR = 1.30, 95% CI: 1.04-1.63, P = .002, I2 = 0.0%, Tau2 = 0.000), and PTSD (adjusted RR = 1.35, 95% CI: 1.04-1.76, P = .022, I2 = 24.1%, Tau2 = 0.013) in cohort studies. The results of subgroup analysis indicated that long sleep duration was not a risk factor for depression (adjusted RR = 1.15, 95% CI: 0.98-1.34, P = .088, I2 = 63.4%, Tau2 = 0.045) and anxiety (adjusted RR = 1.37, 95% CI: 0.93-2.03, P = .114, I2 = 0.0%, Tau2 = 0.000).

CONCLUSIONS

Short sleep duration, not long sleep duration, is an independent predictor of developing mental disorders, particularly anxiety and depression.

Standardized Extract of Valeriana officinalis Improves Overall Sleep Quality in Human Subjects with Sleep Complaints: A Randomized, Double-Blind, Placebo-Controlled, Clinical Study

INTRODUCTION

Sleep deficit or poor sleep leads to ill-health, whereas sleep deprivation for longer periods of time increases the risk of developing adverse conditions associated with poor quality of life, and high socioeconomic impact. The treatments for sleep disturbances include melatonin and over-the-counter medicines like diphenhydramine and doxylamine, all of which have negative side effects. Valerian (Valeriana officinalis L.) is a traditional herb and the most preferred alternate sleep solution to manage sleep complaints.

METHODS

Eighty adult subjects with sleep complaints were randomized in 1:1 ratio to receive either V. officinalis extract (VE) or placebo for 8 weeks in a double-blind, placebo-controlled, parallel, clinical study. Primary efficacy endpoints included the Pittsburgh Sleep Quality Index (PSQI) and sleep latency using wrist actigraphy (WA), as well as a number of secondary endpoints, including sleep parameters such as actual sleep time and sleep efficiency using WA, the Epworth Sleepiness Scale (ESS), the Beck Anxiety Inventory (BAI), the Visual Analogue Scale (VAS) for the feeling of waking up refreshed, and a tertiary endpoint of sleep parameters using polysomnography (PSG) in a subset of 20 subjects per group. Safety parameters included physical examination, vital sign measurements, hematology, and clinical chemistry tests. Adverse events and serious adverse events were monitored throughout the study period.

RESULTS

Seventy-two subjects (35 and 37 subjects in the placebo and VE groups, respectively) completed the study and were included in the efficacy assessments. On Days 14, 28, and 56, the PSQI Total Score in the VE group decreased significantly (p < 0.05) compared to the placebo group. Further, the VE group showed significant improvements (p < 0.05) in sleep latency and actual sleep time on Days 3, 14, 28, and 56, and sleep efficiency on Days 14, 28, and 56, as evaluated by WA. There was a decrease (p < 0.05) in anxiety (BAI) on Days 14, 28, and 56, daytime drowsiness (ESS) on Days 28 and 56, and an increased feeling of waking up refreshed (VAS) on Days 28 and 56 compared to placebo. PSG results carried out in subset of subjects revealed significant improvements (p < 0.05) in total sleep time, sleep latency, and sleep efficiency on Day 56 in the VE group compared to the placebo group. No safety concerns were observed throughout the study.

CONCLUSION

VE supplementation significantly improved various subjective and objective parameters of sleep in young subjects with mild insomnia symptoms, such as overall sleep quality, sleep latency, sleep efficiency, and total sleep time. We also observed decreased anxiety and daytime sleepiness, and improved feeling of being refreshed after waking up with VE supplementation. VE was found to be safe and well tolerated throughout the study.

TRIAL REGISTRATION

Clinical Trials Registry of India: CTRI/2022/05/042818.

Sleep Duration and Insomnia with Comorbid Depression and Anxiety Symptoms in Chinese Adults: A Cross-Sectional Study

Purpose

Depression and anxiety are two highly prevalent mental disorders that commonly coexist. However, little is known about the association between sleep and comorbid depressive and anxiety symptoms (CDAS). Therefore, this study aims to explore the relationship between sleep duration, insomnia and CDAS.

Methods

This is a cross-sectional study of 22,004 community adults who participated in the China Multi-Ethnic Cohort (CMEC) study. Chinese version of Patient Health Questionnaire-2 and Generalized Anxiety Disorder-2 were used to screen CDAS in community adults. A positive score on each scale was considered indicative of CDAS. All participants received face-to-face interviews, medical examinations, and biochemical examinations to assess sleep duration and insomnia and collect covariates. The self-reported sleep duration was divided into three groups: <7 hr, 7-9 hr and >9 hr groups. Logistic regression was used to analyze the association between sleep duration, insomnia and CDAS. A restricted cubic spline (RCS) was used to explore the dose-response relationship between sleep duration and CDAS. Stratified analysis based on gender and age was conducted.

Results

Overall, 2.8% (95% CI 2.6%~3.0%) of participants reported having CDAS. After adjusting the potential covariates, sleep duration <7 hr (OR=1.635, 95% CI=1.335~2.004) was significantly associated with CDAS, compared with sleep 7-9 hr. After RCS analysis, there was a nonlinear relationship between sleep duration and CDAS. The increase in the number of types of insomnia, the greater the likelihood of CDAS (p for trend<0.05). In sensitivity analysis, it was found that the results were consistent with those of the main analysis. After stratification by gender and age, the association between sleep duration and CDAS was only observed in female and young and middle-aged adults, not in men and older adults.

Conclusion

Both insufficient sleep duration and insomnia are associated with a higher prevalence of CDAS in Chinese adults.

Aquilaria sinensis leaf tea affects the immune system and increases sleep in zebrafish

The importance of adequate sleep for good health cannot be overstated. Excessive light exposure at night disrupts sleep, therefore, it is important to find more healthy drinks that can promote sleep under sleep-disturbed conditions. The present study investigated the use of A. sinensis (Lour.) Spreng leaf tea, a natural product, to reduce the adverse effects of nighttime light on sleep. Here, Aquilaria sinensis leaf tea at 1.0 and 1.5 g/L significantly increased sleep time in zebrafish larvae (5-7 dpf) with light-induced sleep disturbance. Transcriptome sequencing and qRT-PCR analysis revealed a decrease in the immune-related genes, such as nfkbiab, tnfrsf1a, nfkbiaa, il1b, traf3, and cd40 in the 1.5 g/L Aquilaria sinensis leaf tea treatment group. In addition, a gene associated with sleep, bhlhe41, showed a significant decrease. Moreover, Aquilaria sinensis leaf tea suppressed the increase in neutrophils of Tg(mpo:GFP) zebrafish under sleep-disturbed conditions, indicating its ability to improve the immune response. Widely targeted metabolic profiling of the Aquilaria sinensis tea using ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry (UPLC-ESI-MS/MS) revealed flavonoids as the predominant component. Network pharmacological and molecular docking analyses suggested that the flavonoids quercetin and eupatilin in Aquilaria sinensis leaf tea improved the sleep of zebrafish by interacting with il1b and cd40 genes under light exposure at night. Therefore, the results of the study provide evidence supporting the notion that Aquilaria sinensis leaf tea has a positive impact on sleep patterns in zebrafish subjected to disrupted sleep due to nighttime light exposure. This suggests that the utilization of Aquilaria sinensis leaf tea as a potential therapeutic intervention for sleep disturbances induced by light may yield advantageous outcomes.

Impact of sleep deprivation on neurocognition and inflammation in rhesus macaques

Sleep deprivation in humans is associated with both cognitive impairment and immune dysregulation. An animal model of neuropathogenesis may provide insight to understand the effects of sleep deprivation on the brain. Human neurocognition is more closely mirrored by nonhuman primates (NHP) than other animals. As such, we developed an NHP model to assess the impact of sleep deprivation on neurocognition and markers of systemic immune activation. Six male rhesus macaques underwent three rounds of sleep deprivation (48 h without sleep) at days 0, 14, and 28. We performed domain specific cognitive assessments using the Cambridge Neuropsychological Test Automated Battery (CANTAB) via a touch screen before and after 24 and 48 h of sleep deprivation. Immune activation markers were measured in the blood by multiplex assay and flow cytometry. Although we observed variability in cognitive performance between the three rounds of sleep deprivation, cognitive impairments were identified in all six animals. We noted more cognitive impairments after 48 h than after 24 h of sleep deprivation. Following 48 h of sleep deprivation, elevations in markers of immune activation in the blood were observed in most animals. The observed impairments largely normalized after sleep. The co-occurrence of systemic immune alterations and cognitive impairment establishes this model as useful for studying the impact of sleep deprivation on neurobehavior and immune perturbations in rhesus macaques.

Lactiplantibacillus plantarum 124 Modulates Sleep Deprivation-Associated Markers of Intestinal Barrier Dysfunction in Mice in Conjunction with the Regulation of Gut Microbiota

Intestinal diseases caused by sleep deprivation (SD) are severe public health threats worldwide. However, whether or not probiotics attenuate the intestinal damage associated with SD remains unclear. In this study, we used antibiotic pretreatment and fecal microbiota transplantation to investigate the protective role of Lactiplantibacillus plantarum (L. plantarum) 124 against SD-related intestinal barrier damage in C57BL/6 mice. Compared with those of a normal sleeping mouse, we observed that intestinal antioxidant capacity and anti-inflammatory cytokine levels were decreased, while pro-inflammatory cytokines were increased in sleep deprivation mice with an increasing duration of sleep deprivation. This resulted in decreased tight junction protein expression and increased intestinal barrier permeability. In contrast, intragastric administration with L. plantarum 124 reversed SD-associated intestinal oxidative stress, inflammation, colonic barrier damage, and the dysbiosis of the microbiota in the colon. In addition, L. plantarum 124 restored gut microbiota homeostasis via restoring abundance, including that of Dubosiella, Faecalibaculum, Bacillus, Lachnoclostridium, and Bifidobacterium. Further studies showed that gut microbiota mediated SD-associated intestinal damage and the treatment L. plantarum 124 in SD-associated colonic barrier damage. L. plantarum 124 is a potential candidate for alleviating SD-associated intestinal barrier damage. Overall, L. plantarum 124 consumption attenuates intestinal oxidative stress, inflammation, and intestinal barrier damage in SD-associated mice via the modulation of gut microbes.

Sleep Deprivation and Its Consequences

OBJECTIVE

This article reviews the clinical, cognitive, behavioral, and physiologic consequences of sleep deprivation in relation to general neurology practice.

LATEST DEVELOPMENTS

Despite being one of the most common sleep problems in modern society, the role of sleep deprivation is underrecognized and underestimated in clinical medicine and general neurology practice. The recognition, diagnosis, and management of sleep deprivation in neurologic practice have only recently received close attention. The consequences of sleep deprivation involve all aspects of general neurology practice, including individuals with neurologic disease, neurologists, communities, and health care systems. The identification and timely management of sleep deprivation symptoms may help to improve symptoms of underlying primary neurologic disorders.

ESSENTIAL POINTS

This article emphasizes complexities related to the identification and evaluation of sleep deprivation in general neurology practice and describes the consequences of sleep deprivation. By recognizing sleep deprivation in patients with neurologic conditions, the neurologist can provide comprehensive care and contribute to improved clinical and neurologic outcomes.

Therapeutic effects of growth hormone in a rat model of total sleep deprivation: Evaluating behavioral, hormonal, biochemical and electrophysiological parameters

OBJECTIVE

Total sleep deprivation (TSD) causes several harmful changes in the brain, including memory impairment, increased stress and depression levels, as well as reduced antioxidant activity. Growth hormone (GH) has been shown to boost antioxidant levels while improving memory and depression. The present study was conducted to explain the possible effects of exogenous GH against behavioral and biochemical disorders caused by TSD and the possible mechanisms involved.

MAIN METHODS

To induce TSD, rats were housed in homemade special cages equipped with stainless steel wire conductors to induce general and inconsistent TSD. They received a mild repetitive electric shock to their paws every 10 min for 21 days. GH (1 ml/kg, sc) was administered to rats during induction of TSD for 21 days. Memory retrieval, anxiety, depression-like behaviors, pain behaviors, antioxidant activity, hippocampal level of BDNF, and simultaneously brain electrical activity were measured at scheduled times after TSD.

KEY FINDINGS

The results showed that GH treatment improved memory (p < 0.001) in the PAT test of rats exposed to TSD. These beneficial effects were associated with lowering the level of anxiety and depression-like behavior (p < 0.001), rising the pain threshold (p < 0.01), increasing the activity of antioxidants (p < 0.01), hippocampal BDNF (p < 0.001), and regular brain electrical activity.

SIGNIFICANCE

Our findings show that GH plays a key role in modulating memory, anxiety and depression behaviors, as well as reducing oxidative stress and improve hippocampal single-unit activity in the brain during TSD.

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.

Feasibility and preliminary efficacy for morning bright light therapy to improve sleep and plasma biomarkers in US Veterans with TBI. A prospective, open-label, single-arm trial

Mild traumatic brain injury (TBI) is associated with persistent sleep-wake dysfunction, including insomnia and circadian rhythm disruption, which can exacerbate functional outcomes including mood, pain, and quality of life. Present therapies to treat sleep-wake disturbances in those with TBI (e.g., cognitive behavioral therapy for insomnia) are limited by marginal efficacy, poor patient acceptability, and/or high patient/provider burden. Thus, this study aimed to assess the feasibility and preliminary efficacy of morning bright light therapy, to improve sleep in Veterans with TBI (NCT03578003). Thirty-three Veterans with history of TBI were prospectively enrolled in a single-arm, open-label intervention using a lightbox (~10,000 lux at the eye) for 60-minutes every morning for 4-weeks. Pre- and post-intervention outcomes included questionnaires related to sleep, mood, TBI, post-traumatic stress disorder (PTSD), and pain; wrist actigraphy as a proxy for objective sleep; and blood-based biomarkers related to TBI/sleep. The protocol was rated favorably by ~75% of participants, with adherence to the lightbox and actigraphy being ~87% and 97%, respectively. Post-intervention improvements were observed in self-reported symptoms related to insomnia, mood, and pain; actigraphy-derived measures of sleep; and blood-based biomarkers related to peripheral inflammatory balance. The severity of comorbid PTSD was a significant positive predictor of response to treatment. Morning bright light therapy is a feasible and acceptable intervention that shows preliminary efficacy to treat disrupted sleep in Veterans with TBI. A full-scale randomized, placebo-controlled study with longitudinal follow-up is warranted to assess the efficacy of morning bright light therapy to improve sleep, biomarkers, and other TBI related symptoms.

The association of sleep duration and quality with depressive symptoms in older Chinese women

Poor sleep quality or short and long sleep duration are associated with many negative health outcomes, such as diabetes, hypertension, and fatigue, which may directly or indirectly correlate with poor mental health. Although, the association between sleep duration and quality, and depressive symptoms has been examined, the results of these studies were inconsistent and evidence specifically on older women is lacking. Therefore, we designed a cross-sectional study to evaluate the association between sleep duration and quality, and depressive symptoms in a relatively large sample of older Chinese women. The data were collected from 1,429 older women aged ≥60 years during bone-health examinations in Shanghai. Information on sleep duration and quality were assessed using a self-reported questionnaire. Depressive symptoms were assessed using the Zung self-rating depression scale (SDS), and depressive symptoms were considered present for SDS scores ≥ 45. Logistic regression models were used to analyze the association between sleep and depressive symptoms. After adjusting for all potential confounding factors, a J-shaped association was found between sleep duration and depressive symptoms. When a sleep duration of 6–8 hours was set as a reference, the odds ratios and 95% confidential intervals of short and long sleep duration were 1.31 (0.99, 1.73) and 2.10 (1.40, 3.16), respectively. Moreover, sleep quality was inversely associated with the prevalence of depressive symptoms (p for trend = 0.040). When the SDS cut-off score defining depressive symptoms was changed to 40 and 50, these associations were somewhat weakened, but the trend did not change. This study replicated and extended prior research findings that sleep duration and quality may influence mental health in older women.

Sleep Deprivation, Immune Suppression and SARS-CoV-2 Infection

Sleep health and its adaptation to individual and environmental factors are crucial to promote physical and mental well-being across animal species. In recent years, increasing evidence has been reported regarding the relationship between sleep and the immune system and how sleep disturbances may perturb the delicate balance with severe repercussions on health outcomes. For instance, experimental sleep deprivation studies in vivo have reported several major detrimental effects on immune health, including induced failure of host defense in rats and increased risk for metabolic syndrome (MetS) and immune suppression in humans. In addition, two novel risk factors for dysregulated metabolic physiology have recently been identified: sleep disruption and circadian misalignment. In light of these recent findings about the interplay between sleep and the immune system, in this review, we focus on the relationship between sleep deprivation and immunity against viruses, with a special interest in SARS-CoV-2 infection.

Sleep Disruption Worsens Seizures: Neuroinflammation as a Potential Mechanistic Link

Sleep disturbances, such as insomnia, obstructive sleep apnea, and daytime sleepiness, are common in people diagnosed with epilepsy. These disturbances can be attributed to nocturnal seizures, psychosocial factors, and/or the use of anti-epileptic drugs with sleep-modifying side effects. Epilepsy patients with poor sleep quality have intensified seizure frequency and disease progression compared to their well-rested counterparts. A better understanding of the complex relationship between sleep and epilepsy is needed, since approximately 20% of seizures and more than 90% of sudden unexpected deaths in epilepsy occur during sleep. Emerging studies suggest that neuroinflammation, (e.g., the CNS immune response characterized by the change in expression of inflammatory mediators and glial activation) may be a potential link between sleep deprivation and seizures. Here, we review the mechanisms by which sleep deprivation induces neuroinflammation and propose that neuroinflammation synergizes with seizure activity to worsen neurodegeneration in the epileptic brain. Additionally, we highlight the relevance of sleep interventions, often overlooked by physicians, to manage seizures, prevent epilepsy-related mortality, and improve quality of life.

Toward Predicting Human Performance Outcomes From Wearable Technologies: A Computational Modeling Approach

Wearable technologies for measuring digital and chemical physiology are pervading the consumer market and hold potential to reliably classify states of relevance to human performance including stress, sleep deprivation, and physical exertion. The ability to efficiently and accurately classify physiological states based on wearable devices is improving. However, the inherent variability of human behavior within and across individuals makes it challenging to predict how identified states influence human performance outcomes of relevance to military operations and other high-stakes domains. We describe a computational modeling approach to address this challenge, seeking to translate user states obtained from a variety of sources including wearable devices into relevant and actionable insights across the cognitive and physical domains. Three status predictors were considered: stress level, sleep status, and extent of physical exertion; these independent variables were used to predict three human performance outcomes: reaction time, executive function, and perceptuo-motor control. The approach provides a complete, conditional probabilistic model of the performance variables given the status predictors. Construction of the model leverages diverse raw data sources to estimate marginal probability density functions for each of six independent and dependent variables of interest using parametric modeling and maximum likelihood estimation. The joint distributions among variables were optimized using an adaptive LASSO approach based on the strength and directionality of conditional relationships (effect sizes) derived from meta-analyses of extant research. The model optimization process converged on solutions that maintain the integrity of the original marginal distributions and the directionality and robustness of conditional relationships. The modeling framework described provides a flexible and extensible solution for human performance prediction, affording efficient expansion with additional independent and dependent variables of interest, ingestion of new raw data, and extension to two- and three-way interactions among independent variables. Continuing work includes model expansion to multiple independent and dependent variables, real-time model stimulation by wearable devices, individualized and small-group prediction, and laboratory and field validation.

Sleep quality and COVID-19 outcomes: the evidence-based lessons in the framework of predictive, preventive and personalised (3P) medicine

Sleep quality and duration play a pivotal role in maintaining physical and mental health. In turn, sleep shortage, deprivation and disorders are per evidence the risk factors and facilitators of a broad spectrum of disorders, amongst others including depression, stroke, chronic inflammation, cancers, immune defence insufficiency and individual predisposition to infection diseases with poor outcomes, for example, related to the COVID-19 pandemic. Keeping in mind that COVID-19-related global infection distribution is neither the first nor the last pandemic severely affecting societies around the globe to the costs of human lives accompanied with enormous economic burden, lessons by predictive, preventive and personalised (3P) medical approach are essential to learn and to follow being better prepared to defend against global pandemics. To this end, under extreme conditions such as the current COVID-19 pandemic, the reciprocal interrelationship between the sleep quality and individual outcomes becomes evident, namely, at the levels of disease predisposition, severe versus mild disease progression, development of disease complications, poor outcomes and related mortality for both - population and healthcare givers. The latter is the prominent example clearly demonstrating the causality of severe outcomes, when the long-lasting work overload and shift work rhythm evidently lead to the sleep shortage and/or deprivation that in turn causes immune response insufficiency and strong predisposition to the acute infection with complications. This article highlights and provides an in-depth analysis of the concerted risk factors related to the sleep disturbances under the COVID-19 pandemic followed by the evidence-based recommendations in the framework of predictive, preventive and personalised medical approach.

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 feasibility of at-home sleep extension in adolescents and young adults: A meta-analysis and systematic review

Insufficient sleep duration is detrimental to health and performance and is alarmingly common in adolescents and young adults. The aim of this pre-registered meta-analysis was to determine the feasibility of at-home sleep extension as a means to improve sleep duration and daytime sleepiness, and maintain or improve sleep quality and efficiency, in adolescents and young adults. Peer-reviewed journal articles and dissertations were screened to identify studies with at least five consecutive days of at-home sleep extension, pre- and post-extension measurement of sleep duration, and participants 13-30 years of age. Out of 2254 studies assessed for eligibility, 17 met review inclusion criteria - seven in adolescents and ten in young adults. At-home extension of sleep opportunity reliably increased sleep duration and sleep quality, and decreased daytime sleepiness when compared to unmanipulated sleep opportunity. These results indicate that at-home sleep extension is feasible in adolescents and young adults. However, the degree of improvement in sleep duration, sleep quality, and daytime sleepiness varied by study population and sleep extension method, which will have downstream consequences for the effectiveness of sleep extension as an experimental manipulation and intervention to improve health and performance during adolescence and young adulthood.

Sleep Deprivation and Neurological Disorders

Sleep plays an important role in maintaining neuronal circuitry, signalling and helps maintain overall health and wellbeing. Sleep deprivation (SD) disturbs the circadian physiology and exerts a negative impact on brain and behavioural functions. SD impairs the cellular clearance of misfolded neurotoxin proteins like α-synuclein, amyloid-β, and tau which are involved in major neurodegenerative diseases like Alzheimer's disease and Parkinson's disease. In addition, SD is also shown to affect the glymphatic system, a glial-dependent metabolic waste clearance pathway, causing accumulation of misfolded faulty proteins in synaptic compartments resulting in cognitive decline. Also, SD affects the immunological and redox system resulting in neuroinflammation and oxidative stress. Hence, it is important to understand the molecular and biochemical alterations that are the causative factors leading to these pathophysiological effects on the neuronal system. This review is an attempt in this direction. It provides up-to-date information on the alterations in the key processes, pathways, and proteins that are negatively affected by SD and become reasons for neurological disorders over a prolonged period of time, if left unattended.

Does the compromised sleep and circadian disruption of night and shiftworkers make them highly vulnerable to 2019 coronavirus disease (COVID-19)?

Rotating and permanent night shiftwork schedules typically result in acute and sometimes chronic sleep deprivation plus acute and sometimes chronic disruption of the circadian time structure. Immune system processes and functionalities are organized as circadian rhythms, and they are also strongly influenced by sleep status. Sleep is a vital behavioral state of living beings and a modulator of immune function and responsiveness. Shiftworkers show increased risk for developing viral infections due to possible compromise of both innate and acquired immunity responses. Short sleep and sleep loss, common consequences of shiftwork, are associated with altered integrity of the immune system. We discuss the possible excess risk for COVID-19 infection in the context of the common conditions among shiftworkers, including nurses, doctors, and first responders, among others of high exposure to the contagion, of sleep imbalance and circadian disruption.

ABBREVIATIONS

ACE2: Angiotensin-converting enzyme 2; APC: Antigen.-presenting .cells; CCL: Chemokine (C-C motif) ligand; CD⁺: .Adhesion molecule expression; COVID-19: 2019 coronavirus disease; DCs: Dendritic cells; GH: Growth hormone; HPA: Hypothalamic-pituitary-adrenal; HSF: Heat shock factor; HSP70: Heat shock protein 70; HSP90: Heat shock protein 90; IL: Interleukin; INFγ: Interferon-gamma; LT/LB: T/B lymphocytes; MHC: Major histocompatibility complex; NK: Natural .killer; RAAS: renin-angiotensin-aldosterone system; SARS: .Severe acute respiratory syndrome; SCN: Suprachiasmatic nucleus;SD: Sleep deprivation; SNS: Sympathetic nervous system; Th1/Th2: T helper lymphocytes 1/2; TLR2/TLR4: Toll-like receptor 2/4; TNF-α: Tumor .necrosis .factor alpha; VEGF: Vascular endothelial growth factor.

Neuromodulation of the Pineal Gland via Electrical Stimulation of Its Sympathetic Innervation Pathway

Stimulation of the pineal gland via its sympathetic innervation pathway results in the production of N-acetylserotonin and melatonin. Melatonin has many therapeutic roles and is heavily implicated in the regulation of the sleep-wake cycle. In addition, N-acetylserotonin has recently been reported to promote neurogenesis in the brain. Upregulation of these indoleamines is possible via neuromodulation of the pineal gland. This is achieved by electrical stimulation of structures or fibres in the pineal gland sympathetic innervation pathway. Many studies have performed such pineal neuromodulation using both invasive and non-invasive methods. However, the effects of various experimental variables and stimulation paradigms has not yet been reviewed and evaluated. This review summarises these studies and presents the optimal experimental protocols and stimulation parameters necessary for maximal upregulation of melatonin metabolic output.

The association between allergic rhinitis and sleep: A systematic review and meta-analysis of observational studies

This systematic review and meta-analysis examines the associations of allergic rhinitis with sleep duration and sleep impairment. Observational studies published before August 2019 were obtained through English language literature searches in the PubMed, Embase, and CINAHL databases. Mean differences and odds ratios with 95% confidence intervals were extracted and used for meta-analysis. Heterogeneity was confirmed by the I2-heterogeneity test. Subgroup analysis was conducted to evaluate the influence of study design. The Grading of Recommendations Assessment, Development, and Evaluation approach was used to determine the level of evidence. In total, 2544 records were identified through database searches; 914 duplicate records were excluded, 1452 records were removed after screening of titles and abstracts, 151 records were excluded after full-text screening, and 27 articles were included in the final meta-analyses. A total of 240,706,026 patients (19,444,043 with allergic rhinitis) were considered. No significant difference in sleep duration between the allergic rhinitis and the control groups was found. Patients with allergic rhinitis presented with significantly higher sleep quality scores, sleep disturbances scores, and sleep latency scores; more frequent use of sleep medications; and lower sleep efficiency as measured by the Pittsburgh Sleep Quality Index and polysomnography. Meta-analyses for adjusted odds ratios showed that allergic rhinitis was also associated with higher risks of nocturnal dysfunctions, including insomnia, nocturnal enuresis, restless sleep, sleep-disordered breathing, obstructive sleep apnea, and snoring. Meta-analysis for adjusted odds ratio also showed that allergic rhinitis was associated with daytime dysfunction, including difficulty waking up, daytime sleepiness, morning headache, and the use of sleep medications. The overall quality of evidence ranged from low to very low, indicating that caution is required when interpreting these results. This study demonstrates that there is a significant association of AR with sleep characteristics.

Poor preoperative sleep quality is a risk factor for severe postoperative pain after breast cancer surgery: A prospective cohort study

The aim of this study was to assess the effect of preoperative sleep quality on acute postoperative pain in breast cancer patients.The Pittsburgh Sleep Quality Index questionnaire (PSQI) was used to assess the overall sleep status of women scheduled for unilateral modified radical mastectomy in the past month. Based on the responses, patients were allocated to good sleep group or poor sleep group. Postoperatively, acute pain was assessed using the numerical rating score in the first 24 hours; in addition, the requirement of analgesics and the incidence of postoperative complications were recorded.A total of 108 breast surgery patients were enrolled. Based on the PSQI results, 55 (51%) patients were allocated to poor sleep group and 53 (49%) to good sleep group. Pain scores were similar in the 2 groups at the end of surgery (P = .589); however, poor sleep group reported higher postoperative pain scores than the good sleep group at 2 (P = .002), 6 (P < .001), 12 (P < .001), and 24 (P = .002) hours after surgery. The incidence of severe pain in the poor sleep group was higher than that in the good sleep group (27% vs 8%, P = .018), and the ratio of participants who required rescued analgesics was greater in the poor sleep group (52% vs 22%, P = .002). In addition, patients with poor sleep quality had more postoperative complications and longer hospital stay.In this study, breast cancer patients with poor preoperative sleep quality reported more severe postoperative pain, required more analgesics, experienced more complications, and had longer hospital stay.

The Global Problem of Insufficient Sleep and Its Serious Public Health Implications

Good sleep is necessary for good physical and mental health and a good quality of life. Insufficient sleep is a pervasive and prominent problem in the modern 24-h society. A considerable body of evidence suggests that insufficient sleep causes hosts of adverse medical and mental dysfunctions. An extensive literature search was done in all the major databases for “insufficient sleep” and “public health implications” in this review. Globally, insufficient sleep is prevalent across various age groups, considered to be a public health epidemic that is often unrecognized, under-reported, and that has rather high economic costs. This paper addresses a brief overview on insufficient sleep, causes, and consequences, and how it adds to the existing burden of diseases. Insufficient sleep leads to the derailment of body systems, leading to increased incidences of cardiovascular morbidity, increased chances of diabetes mellitus, obesity, derailment of cognitive functions, vehicular accidents, and increased accidents at workplaces. The increased usage of smart phones and electronic devices is worsening the epidemic. Adolescents with insufficient sleep are likely to be overweight and may suffer from depressive symptoms. The paper concludes by emphasizing sleep quality assessments as an important early risk indicator, thereby reducing the incidence of a wide spectrum of morbidities.

Relationship between Problematic Internet Use, Sleep Problems, and Oral Health in Korean Adolescents: A National Survey

We examined the relationship between Problematic Internet Use (PIU), sleep (sleep satisfaction, sleep duration), and experience of oral disease symptoms in Korean adolescents by gender. This cross-sectional study utilized the 6th (2010) Korean Youth Risk Behavior Web-based Survey. Participants comprised 74,980 students from 400 middle schools and 400 high schools nationwide. Among these, 73,238 students from 799 schools (38,391 boys, 34,847 girls, aged 13–18 years) were included in the analysis (inclusion rate = 97.7%). Multiple logistic regression and analysis of moment structures (AMOS) analyses were performed to identify meaningful relationships between the three factors. The “high risk group” of problematic internet usage had increased experience of oral disease symptoms (boys: adjusted odds ratio (AOR) = 1.92, 95% confidence interval (CI) = 1.63–2.28, girls: AOR = 1.98, 95% CI = 1.50–2.63) compared to the general group. Boys who used the Internet for “5–6 h” had a higher risk of oral disease symptoms compared to those who used it for “less than 1 h” (OR = 1.24, 95% CI = 1.01–1.53); however, this difference was not significant in Models II and III. For girls, the risk of 5–6 h of use (Model I: OR = 1.69, 95% CI = 1.40–2.04) was higher than that of the boys. In addition, the difference was significant in Models II and III for girl students who used the Internet for 5–6 h. In subgroup analysis, the high-risk group had a higher odds ratio for mild symptoms of bad breath to severe symptoms such as sore and bleeding gums. In addition, in the path analysis, PIU affected sleep and indirectly affected oral health. Direct and indirect causal relationships between the three factors were confirmed. Therefore, it is important to recognize that PIU can have a detrimental effect on mental, physical, and oral health.

Regional differences in the risk of insomnia symptoms among patients from general hospital outpatient clinics

BACKGROUND

Region-specific differences in the prevalence of insomnia symptoms in outpatient clinics in China have received little systematic study. This study was conducted preliminarily to examine region-specific differences in the risk of insomnia symptoms in Chinese outpatients.

METHOD

In total, 4,399 adult outpatients (urban vs rural residents: 1,768 vs 2,631) who completed three questions focusing on insomnia symptoms were included. Their sociodemographic and clinical information were collected with standardized questionnaires.

RESULTS

The prevalence of self-reported insomnia symptoms in urban residents (23.4%) was more frequent than the prevalence in rural residents (21.2%). The estimated prevalence of insomnia symptoms was significantly lower in rural than urban residents after adjusting for the potential confounders (P=0.015). Similarly, more urban (22.9%) than rural (13.4%) residents with insomnia symptoms had significantly higher treatment rates (χ ²=14.9, P<0.001). Multiple regression analyses showed that depressive symptoms, old age, and low education level were the most common risk factors for insomnia symptoms in both urban and rural residents.

CONCLUSION

Our findings show that the prevalence of insomnia symptoms was relatively lower in rural than urban residents. Longitudinal studies are warranted to confirm the current findings.

Poor habitual sleep efficiency is associated with increased cardiovascular and cortisol stress reactivity in men

Inadequate sleep and psychological stress can both elevate physiological stress markers, such as cortisol. Prior studies that have applied induced psychosocial stress after a night of experimental sleep deprivation have found these effects to be compounded. We examined whether the relationship between stress reactivity and poor sleep also extends to habitual sleep patterns. Fifty-nine adult male participants were recruited. Habitual sleep patterns were monitored with actigraphy for a week. Participants subsequently underwent the Trier Social Stress Test. Cardiovascular responses and salivary cortisol were measured at baseline, during stress, and during recovery. Subjects who showed poor habitual sleep efficiency during the week before stress induction responded with higher stress-related elevations of blood pressure and cortisol levels as compared to subjects with high sleep efficiency. This relationship between poor sleep efficiency and elevated blood pressure persisted during the post-stress recovery period. Similar associations between total sleep time in the week prior to the stress induction and physiological reactivity did not reach significance. Our findings indicate that habitual low sleep efficiency exaggerates cardiovascular and neuroendocrine effects of psychosocial stress, in a male population.

Associations of Self-Reported Sleep Quality with Circulating Interferon Gamma-Inducible Protein 10, Interleukin 6, and High-Sensitivity C-Reactive Protein in Healthy Menopausal Women

Introduction

Sleep disturbance is very common in menopausal women and poor sleep quality has been linked to systemic inflammation. However, the impact of poor sleep quality on health outcomes of menopausal women remains unclear. This study evaluated the relationships between sleep quality and inflammation in menopausal women.

Participants and design

This cross-sectional study enrolled 281 healthy women aged 45 to 60 years. The Pittsburgh Sleep Quality Index (PSQI) was used to measure quality of sleep. Multiplex assays were used to measure the levels of 9 cytokines in morning fasting plasma samples. Other variables measured in this study included clinical characteristics and high-sensitivity C-reactive protein (hs-CRP).

Setting

The study was performed at a medical center.

Results

The 281 participants comprised 79 (28%) perimenopausal women and 202 (72%) postmenopausal women. Global PSQI scores were positively correlated with plasma hs-CRP levels (P = 0.012) and were marginally associated with interferon gamma-inducible protein-10 (IP10), interleukin 6 (IL6), and macrophage inflammatory protein-1beta (MIP-1β) levels. After adjusting for age, body mass index, menopause duration, and follicle stimulating hormone, multiple linear regression analysis revealed that high PSQI scores and sleep efficiency < 65% were associated with elevated plasma levels of hs-CRP, IP10, and IL6. In addition, sleep duration < 5 hours was associated with high hs-CRP levels.

Conclusion

Our data show that poor sleep quality and low sleep efficiency are associated with elevated levels of circulating inflammatory factors IP10, IL6 and hs-CRP and that short sleep duration is associated with high levels of hs-CRP in menopausal women. These findings provide novel evidence that poor sleep quality is linked to low-grade systemic inflammation in menopausal women.

Sensory Hypersensitivity Predicts Reduced Sleeping Quality in Patients With Major Affective Disorders

The goal of this study was to examine the sensory profile (expressed as hypersensitivity or hyposensitivity) of patients with major affective disorders and its relative contribution to the prediction of sleep quality while considering affective temperaments and depression, which may impact sleep quality. We recruited 176 participants (mean age, 47.3 y), of whom 56.8% had a diagnosis of unipolar major depressive disorder and 43.2% a diagnosis of bipolar disorder. Reduced sleep quality was evaluated using the Pittsburgh Sleep Quality Index. Affective temperaments were assessed using the Temperament Evaluation of Memphis, Pisa, Paris and San Diego. Sensory hypersensitivity, assessed using the Adolescent/Adult Sensory Profile, significantly distinguished between poor and good sleepers. Sleep quality was mainly predicted by the Beck Depression Inventory-II total score and anxious temperament. Sensory hypersensitivity contributed to this prediction mainly with regard to sleep efficiency and related daytime dysfunction.

Sleep, immunity and shift workers: A review

To date, shift workers represent between 15% and 25% of the modern day workforce. Work time poses a great challenge to workers as it requires that they balance productivity and sleep time between shifts. As a result, these workers experience chronic sleep deprivation with increased fatigue and drowsiness due to this sleep deprivation. The impact of this kind of work on the immune system is not yet known. We conducted a literature review with the aim of evaluating articles on this specific type of work's effects on sleep and immunity.

Blood-Brain Barrier Disruption Induced by Chronic Sleep Loss: Low-Grade Inflammation May Be the Link

Sleep is a vital phenomenon related to immunomodulation at the central and peripheral level. Sleep deficient in duration and/or quality is a common problem in the modern society and is considered a risk factor to develop neurodegenerative diseases. Sleep loss in rodents induces blood-brain barrier disruption and the underlying mechanism is still unknown. Several reports indicate that sleep loss induces a systemic low-grade inflammation characterized by the release of several molecules, such as cytokines, chemokines, and acute-phase proteins; all of them may promote changes in cellular components of the blood-brain barrier, particularly on brain endothelial cells. In the present review we discuss the role of inflammatory mediators that increase during sleep loss and their association with general disturbances in peripheral endothelium and epithelium and how those inflammatory mediators may alter the blood-brain barrier. Finally, this manuscript proposes a hypothetical mechanism by which sleep loss may induce blood-brain barrier disruption, emphasizing the regulatory effect of inflammatory molecules on tight junction proteins.

Sleep Disturbance and Depression as Barriers to Adherence

This study examined the relationships among subjective sleep disturbance, depressive symptoms, and adherence to medications among HIV-infected women. HIV-infected women ( N = 173) were recruited through community AIDS service organizations throughout South Carolina. Participants completed the Pittsburgh Sleep Quality Index (PSQI), the Centers for Epidemiological Studies Depression Scale (CES-D), and a modified version of the Adults AIDS Clinical Trials Group Adherence Baseline Questionnaire. Women who reported greater sleep disturbance also reported a higher level of depressive symptoms and reported poor adherence to their medication regimen. Depression helped to explain the relationship between sleep quality and adherence. Results indicate that assessment and management of sleep disturbance and depressive symptoms in women with HIV disease is important to promote medication adherence.

The Contribution of Individual Differences in Hostility to the Associations between Daily Interpersonal Conflict, Affect, and Sleep

Adults of both sexes completed phone interviews assessing interpersonal conflict, state negative and positive affect (NA and PA), and sleep from the previous night on 7 consecutive evenings. Greater interpersonal conflict was associated with increased NA and decreased PA that day and increased sleep disturbance that night (measured on the next day). Mediational analyses were consistent with NA on the conflict day (but not PA) being a partial mediator of the prospective relation between greater conflict and greater sleep disturbance. Greater NA was associated with retrospective reports of obtaining less sleep and experiencing greater sleep disturbance the previous night but conflict was not associated with NA or PA on the following day. The associations between conflict and greater NA and sleep disturbance were exacerbated among individuals higher in cynical hostility. This exacerbation was not due to individuals higher in hostility reporting a greater number conflicts or more severe conflicts.

Effects of different periods of paradoxical sleep deprivation and sleep recovery on lipid and glucose metabolism and appetite hormones in rats

Sleep has a fundamental role in the regulation of energy balance, and it is an essential and natural process whose precise impacts on health and disease have not yet been fully elucidated. The aim of this study was to assess the consequences of different periods of paradoxical sleep deprivation (PSD) and recovery from PSD on lipid profile, oral glucose tolerance test (OGTT) results, and changes in insulin, corticosterone, ghrelin, and leptin concentrations. Three-month-old male Wistar rats weighing 250–350 g were submitted to 24, 96, or 192 h of PSD or 192 h of PSD with 480 h of recovery. The PSD was induced by the multiple platforms method. Subsequently, the animals were submitted to an OGTT. One day later, the animals were killed and the levels of triglycerides, total cholesterol, lipoproteins (low-density lipoprotein, very-low-density lipoprotein, and high-density lipoprotein), insulin, ghrelin, leptin, and corticosterone in plasma were quantified. There was a progressive decrease in body weight with increasing duration of PSD. The PSD induced basal hypoglycemia over all time periods evaluated. Evaluation of areas under the curve revealed progressive hypoglycemia only after 96 and 192 h of PSD. There was an increase in corticosterone levels after 192 h of PSD. We conclude that PSD induces alterations in metabolism that are reversed after a recovery period of 20 days.

Association between sleep deficiency and cardiometabolic disease: implications for health disparities

BACKGROUND

Cardiometabolic diseases, which include obesity, diabetes, hypertension, and cardiovascular disease, are associated with reduced quality of life and reduced life expectancy. Unfortunately, there are racial/ethnic and socioeconomic disparities associated with these diseases such that minority populations, such as African Americans and Hispanics, and those of lower socioeconomic status, experience a greater burden. Several reports have indicated that there are differences in sleep duration and quality that mirror the disparities in cardiometabolic disease. The goal of this paper is to review the association between sleep and cardiometabolic disease risk because of the possibility that suboptimal sleep may partially mediate the cardiometabolic disease disparities.

METHODS

We review both experimental studies that have restricted sleep duration or impaired sleep quality and examined biomarkers of cardiometabolic disease risk, including glucose metabolism and insulin sensitivity, appetite regulation and food intake, and immune function. We also review observational studies that have examined the association between habitual sleep duration and quality, and the prevalence or risk of obesity, diabetes, hypertension, and cardiovascular disease.

CONCLUSION

Many experimental and observational studies do support an association between suboptimal sleep and increased cardiometabolic disease risk.

Relationship between daily isoflavone intake and sleep in Japanese adults: a cross-sectional study

Background

Isoflavones comprise a class of phytoestrogens that resemble human estrogen in chemical structure, and have weak estrogenic effects. Because estrogen modulates sleep duration and quality, we hypothesized that isoflavones would have a beneficial effect on sleep status in a way similar to estrogen. We conducted a cross-sectional study to investigate the relationship between daily isoflavone intake and sleep status in Japanese subjects.

Methods

Our study included 1076 Japanese adults aged 20-78 years. Daily isoflavone intake was assessed using a brief self-administered diet history questionnaire, and sleep was evaluated using a self-reported questionnaire.

Results

The prevalence of regular sleep duration (7–8 h/day) and sufficient sleep quality were 13.3 % and 56.2 %, respectively. After adjusting for potential confounding factors, the odds ratios (95 % CIs) for optimal sleep duration (7–8 h) when higher isoflavone intakes (Q2–Q4) were compared with low isoflavone intake (Q1) were Q2: 0.94 (0.53–1.56); Q3: 1.28 (0.73–2.24); and Q4: 1.84 (1.06–3.18) (p for trend = 0.013). In the final adjusted model, sufficient sleep quality across categories of isoflavone intake was Q1: 1.00 (reference); Q2: 1.30 (0.91–1.84); Q3: 1.48 (1.03–2.12); and Q4: 1.78 (1.22–2.60); (p for trend = 0.002).

Conclusion

Higher daily isoflavone intake was positively associated with optimal sleep duration and quality in a Japanese population. This finding suggests that daily isoflavone intake may have a potentially beneficial effect on sleep status.

A meta-analysis of sleep-promoting interventions during critical illness

BACKGROUND

Sleep quality and quantity are severely reduced in critically ill patients receiving mechanical ventilation with a potential for adverse consequences. Our objective was to synthesize the randomized controlled trials (RCTs) that measured the efficacy of sleep-promoting interventions on sleep quality and quantity in critically ill patients.

METHODS

We included RCTs that objectively measured sleep with electroencephalography or its derivatives and excluded observational studies and those that measured sleep by subjective reports. The research was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

Of 6022 studies identified, 13 met eligibility criteria involving 296 critically ill patients. Eight trials looked at different modes of mechanical ventilation as sleep interventions, and the remaining 5 involved pharmacologic, nonpharmacologic, or environmental interventions. Meta-analysis of the studies revealed that sleep-promoting interventions improved sleep quantity (pooled standardized mean difference [SMD], 0.37; 95% confidence interval [CI], 0.05-0.69; P = .02) and sleep quality through reduction in sleep fragmentation (SMD, -0.31; 95% CI, -0.60 to -0.01; P = .04). Subgroup analysis revealed that timed modes of ventilation improved sleep quantity when compared with spontaneous modes of ventilation (SMD, 0.45; 95% CI, 0.10-0.81; P = .01). Nonmechanical ventilation interventions tended to improve sleep quantity (SMD, 0.65; 95% CI, -0.03 to 1.33; P = .06) and to reduce sleep fragmentation (SMD, -0.29; 95% CI, -0.61 to 0.03; P = .07).

CONCLUSIONS

The synthesized evidence suggests that both mechanical ventilation- and nonmechanical ventilation-based therapies improve sleep quantity and quality in critically ill patients, but the clinical significance is unclear. In the future, adequately powered multicenter RCTs involving pharmacologic interventions to promote sleep in critically ill patients are warranted.

Perceived Immune Status and Sleep: A Survey among Dutch Students

Reduced immune functioning may have a negative impact on sleep and health, and vice versa. A survey among Dutch young adults (18–35 years old) was administered to collect information on perception of reduced immunity and its relationship to sleep disorders, sleep duration, and quality. Sleep disorders were assessed with the SLEEP-50 questionnaire subscales of sleep apnea, insomnia, circadian rhythm disorder, and daily functioning. Dutch young adults (N = 574) completed the survey. Among them, subjects (N = 209; 36.4%) reported perceived reduced immunity. Relative to those with a normal immune status, subjects reporting reduced immunity had significantly higher scores (p = 0.0001) on sleep apnea (2.6 versus 3.6), insomnia (5.1 versus 6.8), and circadian rhythm disorder (2.1 versus 2.7). Subjects reporting reduced immunity also had significantly poorer daily functioning scores (5.4 versus 7.6, p = 0.0001). No differences were observed in total sleep time, but those reporting reduced immunity had significantly poorer ratings of sleep quality (6.8 versus 7.2, p = 0.0001). Our findings suggest that perceived reduced immunity is associated with sleep disturbances, impaired daily functioning, and a poorer sleep quality. Experimental studies including the assessment of immune biomarkers and objective measures of sleep (polysomnography) should confirm the current observations.

Effect of long-term sleep restriction and subsequent recovery sleep on the diurnal rhythms of white blood cell subpopulations

While acute modifications of sleep duration induces a wide array of immune function alterations, less is known of how longer periods with insufficient sleep affect immune functions and how they return to normal once recovery sleep is obtained. The purpose of the present study was to investigate the effects of five days of restricted sleep and a subsequent 7-day period of sleep recovery on white blood cell (WBC) subpopulation count and diurnal rhythms. Nine healthy males participated in a sleep protocol consisting of two baseline days (8h of sleep/night), five nights with restricted sleep (4h of sleep/night) and seven days of recovery sleep (8h of sleep/night). During nine of these days, blood was drawn hourly during night-time end every third hour during daytime, and differential WBC count was analyzed. Gradual increase across the days of sleep restriction was observed for total WBC (p<.001), monocytes (p<.001), neutrophils (p<.001) and lymphocytes (p<.05). Subsequent recovery sleep resulted in a gradual decrease in monocytes (p<.001) and lymphocytes (p=.001), but not in neutrophils that remained elevated over baseline level at the end of the 7-day recovery period. These effects were associated with altered diurnal rhythms of total WBC and neutrophils, restricted sleep being associated with higher levels during the night and at awakening, resulting in a flattening of the rhythm. The diurnal alterations were reversed when recovery sleep was allowed, although the amplitude of total WBC, neutrophils and monocytes was increased at the end of the recovery period in comparison to baseline. Altogether, these data show that long-term sleep restriction leads to a gradual increase of circulating WBC subpopulations and alterations of the respective diurnal rhythms. Although some of the effects caused by five days of restricted sleep were restored within the first days of recovery, some parameters were not back to baseline even after a period of seven recovery days.