Sleep disturbance and longitudinal risk of inflammation: Moderating influences of social integration and social isolation in the Coronary Artery Risk Development in Young Adults (CARDIA) study

Correlation between physical exercise levels, depressive symptoms, and sleep quality in college students: Evidence from electroencephalography

BACKGROUND

In recent years, depression has increasingly become a major global public health issue. Among its common physical symptoms, sleep disturbances are prevalent in individuals with depression and are considered a risk factor for the progression of the disorder. Poor sleep quality may be a significant contributor to depression among college students. However, the EEG indicators that are commonly associated with depressive symptoms and sleep quality, as well as the effects of physical exercise on these EEG indicators, remain unclear.

PURPOSE

This study aims to explore the relationship between physical activity levels, depressive symptoms, and sleep quality among college students, based on resting-state electroencephalography (EEG) data in a cross-sectional study.

METHODS

A total of 342 college students were recruited to assess physical activity levels, depressive symptoms, sleep quality, and EEG data. Pearson correlation coefficients were used to evaluate the relationships among these variables, and the PROCESS macro (Model 4) for SPSS was applied to examine the mediating role of sleep quality in the relationship between physical activity levels and depressive symptoms, with mediation effects tested using the bootstrap method.

RESULTS

A significant difference was observed in the Pittsburgh Sleep Quality Index (PSQI) total scores between students with and without depressive symptoms (T = 9.746, P < 0.001). Students with depressive symptoms showed poorer sleep quality across various dimensions, including sleep duration, sleep onset latency, sleep disturbances, and daytime dysfunction. Depression symptom were positively correlated with Sleep Quality (r = 0.547, P < 0.001), indicating that higher depression symptoms are associated with poorer sleep quality. Correlations between depressive symptoms and EEG power values revealed significant associations with theta and beta2 frequencies in multiple brain regions (P < 0.05). Physical exercise showed a significant negative correlation with Sleep Quality scores (r = -0.158, P = 0.004), and with sleep duration (r = -0.141, P = 0.011) and daytime dysfunction (r = -0.142, P = 0.010). Additionally, physical exercise was negatively correlated with theta band power at F8 (P < 0.05). Mediation analysis demonstrated that physical exercise has a direct effect on depressive symptoms (β = -0.123, 95 % CI = -0.287 to -0.069) and an indirect effect through improved sleep quality (β = -0.074, 95 % CI = -0.089 to -0.016), accounting for 60.16 % and 40.65 % of the total effect, respectively.

CONCLUSION

These findings provide a theoretical basis for developing precise exercise intervention programs to improve depressive symptoms and sleep quality among college students. The results indicate that moderate physical activity can help alleviate depressive symptoms and improve sleep quality, thereby enhancing the overall health of college students.

The role of Klotho and sirtuins in sleep-related cardiovascular diseases: a review study

The prevalence of sleep disorders has been reported from 1.6% to 56.0%, worldwide. Sleep deprivation causes cardiovascular diseases (CVDs) including atherosclerosis, vascular aging, hypertension, heart dysfunction, reduced heart rate variability, and cardiac arrhythmia. Reduced tissue oxygen causes various CVDs by activating pro-inflammatory factors and increasing oxidative stress. Sleep disorders are more important and prevalent in older people and cause more severe cardiovascular complications. On the other hand, the reduction of Klotho level, an age-dependent protein whose expression decreases with age, is associated with age-related diseases. Sirtuins, class III histone deacetylases, also are among the essential factors in postponing cellular aging and increasing the lifespan of organisms, and they do this by regulating different pathways in the cell. Sirtuins and Klotho play an important role in the pathophysiology of CVDS and both have anti-oxidative stress and anti-inflammatory activity. Studies have shown that the levels of Klotho and sirtuins are altered in sleep disorders. In this article, alterations of Klotho and sirtuins in sleep disorders and in the development of sleep-related CVDs were reviewed and the possible signaling pathways were discussed. The inclusion criteria were studies with keywords of different types of sleep disorders and CVDs, klotho, SIRT1-7, and sirtuins in PubMed, Scopus, Embase، Science Direct، Web of Sciences and Google Scholar by the end of 2023. The studies revealed there is a bidirectional relationship between sleep disorders and the serum and tissue levels of Klotho and sirtuins and sleep related-CVDs.

Associations of 24-hour movement behaviors with depressive symptoms in rural-dwelling older adults: a compositional data analysis

BACKGROUND

We aimed to explore the association of sleep duration with depressive symptoms among rural-dwelling older adults in China, and to estimate the impact of substituting sleep with sedentary behavior (SB) and physical activity (PA) on the association with depressive symptoms.

METHODS

This population-based cross-sectional study included 2001 rural-dwelling older adults (age ≥ 60 years, 59.2% female). Sleep duration was assessed using the Pittsburgh Sleep Quality Index. We used accelerometers to assess SB and PA, and the 15-item Geriatric Depression Scale to assess depressive symptoms. Data were analyzed using restricted cubic splines, compositional logistic regression, and isotemporal substitution models.

RESULTS

Restricted cubic spline curves showed a U-shaped association between daily sleep duration and the likelihood of depressive symptoms (P-nonlinear < 0.001). Among older adults with sleep duration < 7 h/day, reallocating 60 min/day spent on SB and PA to sleep were associated with multivariable-adjusted odds ratio (OR) of 0.81 (95% confidence interval [CI] = 0.78-0.84) and 0.79 (0.76-0.82), respectively, for depressive symptoms. Among older adults with sleep duration ≥ 7 h/day, reallocating 60 min/day spent in sleep to SB and PA, and reallocating 60 min/day spent on SB to PA were associated with multivariable-adjusted OR of 0.78 (0.74-0.84), 0.73 (0.69-0.78), and 0.94 (0.92-0.96), respectively, for depressive symptoms.

CONCLUSIONS

Our study reveals a U-shaped association of sleep duration with depressive symptoms in rural older adults and further shows that replacing SB and PA with sleep or vice versa is associated with reduced likelihoods of depressive symptoms depending on sleep duration.

Impact of physical therapy techniques and common interventions on sleep quality in patients with chronic pain: A systematic review

This systematic review aims to find effectful healthcare strategies, with special focus on drug-free interventions and physical therapy, as part of the treatment for sleep in patients with chronic musculoskeletal pain. Data search was conducted across seven scientific databases. This review is deposited in the Prospero International prospective register of systematic reviews (CRD42023452574). Seventeen RCTs from different healthcare fields complied with our inclusion criteria. Two RCTs investigated manual therapy, five RCTs therapeutic exercise, one RCT Fu's subcutaneous needling, two RCTs physical agents (one on balneotherapy and one on cryo-stimulation), two RCTs cognitive-behavioral therapy, and four RCTs pharmacological therapy and their effect on sleep quality and/or quantity in patients suffering from chronic pain. We included the four RCT's in this systematic review with the purpose to be able to compare natural interventions with allopathic ones. As allopathic interventions are more prone to have secondary negative effects than physical therapy, compare the two types of interventions could be in favor of choosing the most effective treatment with the least secondary negative effects. Additionally, two RCTs on neurofeedback and limbic neuromodulation were also included. The results of the included studies suggest that strategies such as manual therapy, therapeutic exercise, Fu's subcutaneous needling, balneotherapy, cryo-stimulation, neurofeedback, limbic neuromodulation, cognitive-behavioral therapy, and pharmacological therapies have positive effects on patients suffering from chronic pain and sleep disturbances, especially when they suffer musculoskeletal pain. Secondary negative effects were found for the possible overuse of certain medicines such as morphine, a huge problem in the United States. Sleep deficiency is an independent risk factor for many diseases, including chronic pain syndrome and therefore more studies are needed to find non-toxic interventions for people suffering sleep disorders associated with systemic diseases and pain.

Tai Chi compared with cognitive behavioral therapy and the reversal of systemic, cellular and genomic markers of inflammation in breast cancer survivors with insomnia: A randomized clinical trial

BACKGROUND

Insomnia contributes to inflammation in breast cancer survivors. This study evaluates whether insomnia treatment reverses inflammation in breast cancer survivors with insomnia.

METHODS

Participants (n = 90) were randomized to 3 months of Tai Chi (n = 45) or cognitive behavioral therapy for insomnia (CBT-I)(n = 45), and followed for one year post-intervention to 15 month endpoint. Our previous report found that Tai Chi as compared to CBT-I resulted in similar rates of insomnia response and remission over 15 months. Here, we analyze changes in plasma C-reactive protein and pro- and anti-inflammatory cytokines, Toll-like receptor (TLR)-4 stimulated monocyte production of interleukin (IL)-6 and tumor necrosis factor-α (TNF), and cellular pro-inflammatory and anti-viral gene expression (Conserved Transcriptional Response to Adversity RNA profile; CTRA) over 15 months.

RESULTS

Insomnia treatment resulted in decreases in the TLR-4 stimulated monocyte production of IL-6, TNF, and their co-expression, as well as decreases in the CTRA profile, decreases inflammatory gene transcripts, and increases in anti-viral gene transcripts over 15 months (all P's < 0.01). In addition, as compared to CBT-I, Tai Chi resulted in greater decreases in plasma IL-6 (P < 0.05), and greater decreases in TLR-4 activated monocyte production of IL-6 and co-expression of IL-6 and TNF at 15 month endpoint. CBT-I resulted in greater increases in anti-viral gene transcripts.

CONCLUSIONS

Administration of either CBT-I or Tai Chi effectively treats insomnia, and shows additional benefits of reducing cellular and genomic markers of inflammation, and increasing anti-viral genomic markers in breast cancer survivors with insomnia. Tai Chi, as compared to CBT-I, yields greater and more durable decreases in systemic- and cellular inflammation. Targeting insomnia might mitigate the risk of inflammation-related co-morbidities in breast cancer survivors.

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.

A narrative review of mechanisms linking romantic relationship experiences to sleep quality

Although a significant body of research has revealed associations between romantic relationship experiences and sleep quality, there has not been clarity regarding the mechanisms underlying such associations. Toward this end, we review the existing studies that have tested mechanisms linking romantic relationship experiences to sleep quality. Guided by both theory and existing research, we organize our review around five key categories of mechanisms that may explain associations between romantic relationship experiences and sleep quality: emotional/affective responses, self-perceptions, social perceptions, self-regulation, and biological functioning. Our review of the literature indicates strong evidence in support of the mediating effects of emotional/affective mechanisms (e.g. emotions and mood states) in explaining associations between various aspects of romantic relationships (e.g. relationship satisfaction, partner conflicts, and attachment orientation) and sleep quality. Although there is ample theoretical support for the other mechanisms proposed, and although all proposed mechanisms have been separately linked to both romantic relationship experiences and sleep quality, few studies have directly tested them, pointing to profitable directions for future research. Understanding underlying mechanisms will enable the development of wise, process-based interventions that target specific mechanisms to improve couple members' sleep quality and romantic relationship functioning.

Inverse association between slow-wave sleep and low-grade inflammation in children and adolescents with major depressive disorder

OBJECTIVE

To investigate the relationship between both self-reported and objective sleep variables and low-grade inflammation in children and adolescents with major depressive disorder (MDD) of moderate to severe symptom severity.

METHODS

In this cross-sectional study, we examined twenty-nine children and adolescents diagnosed with MDD and twenty-nine healthy controls (HC). Following a one-week actigraphy assessment, comprehensive sleep evaluations were conducted, including a one-night sleep EEG measurement and self-reported sleep data. Plasma high-sensitivity C-reactive protein (hsCRP) was employed as a marker to assess low-grade inflammation.

RESULTS

No significant difference in hsCRP levels was observed between participants with MDD and HC. Furthermore, after adjusting for sleep difficulties, hsCRP exhibited no correlation with the severity of depressive symptoms. In HC, levels of hsCRP were not linked to self-reported and objective sleep variables. In contrast, depressed participants showed a significant correlation between hsCRP levels and increased subjective insomnia severity (Insomnia Severity Index; r = 0.41, p < 0.05), increased time spent in the N2 sleep stage (r = 0.47, p < 0.01), and decreased time spent in slow-wave sleep (r = - 0.61, p < 0.001). Upon additional adjustments for body mass index, tobacco use and depression severity, only the inverse association between hsCRP and time spent in slow-wave sleep retained statistical significance. Moderation analysis indicated that group status (MDD vs. HC) significantly moderates the association between slow-wave sleep and hsCRP.

CONCLUSION

Our findings suggest that alterations in the architecture of slow-wave sleep may have a significant influence on modulating low-grade inflammatory processes in children and adolescents with MDD.

The Association Between Diets With High Inflammatory Potential and Sleep Quality and Its Parameters: A Systematic Review

CONTEXT

Dietary components or its overall properties can influence an individual's sleep status.

OBJECTIVE

The aim for this study was to critically search, appraise, and synthesize research evidence on the association between dietary inflammatory index (DII) and sleep quality and its parameters.

DATA SOURCES

Original published studies on adults were obtained from the PubMed, SCOPUS, ScienceDirect, Cochrane Library, and Google Scholar databases.

DATA EXTRACTION

The search was conducted without date limitation until April 2023. Duplicated and irrelevant investigations were screened out, and the results of the remaining articles were descriptively summarized, then critically appraised and analyzed. Possible mechanistic pathways regarding diet, systemic inflammation, and sleep status were discussed.

DATA ANALYSIS

Of the 102 studies searched, 23 articles (n = 4 cohort studies, 18 cross-sectional studies, and 1 intervention study) were included in the final review. The association between DII and sleep status was investigated subjectively in 21 studies and objectively in 6 studies. The main studied sleep outcomes were sleep quality, duration, latency, efficiency, apnea, disturbances, the use of sleeping medications, daytime dysfunctions, wakefulness after sleep onset, and rapid eye movement.

CONCLUSIONS

According to most of the evidence, DII may not be related to overall sleep quality, sleep duration, latency, efficiency, and the use of sleeping medications. The evidence of positive association was greater between a high DII score (pro-inflammatory diet) with daytime dysfunctions, wakefulness after sleep onset, and sleep apnea. There is insufficient evidence to make any conclusion regarding sleep disturbances and rapid eye movement.

Network Pharmacology Analysis of the Potential Pharmacological Mechanism of a Sleep Cocktail

Insomnia, also known as sleeplessness, is a sleep disorder due to which people have trouble sleeping, followed by daytime sleepiness, low energy, irritability, and a depressed mood. It may result in an increased risk of accidents of all kinds as well as problems focusing and learning. Dietary supplements have become popular products for alleviating insomnia, while the lenient requirements for pre-market research result in unintelligible mechanisms of different combinations of dietary supplements. In this study, we aim to systematically identify the molecular mechanisms of a sleep cocktail's pharmacological effects based on findings from network pharmacology and molecular docking. A total of 249 targets of the sleep cocktail for the treatment of insomnia were identified and enrichment analysis revealed multiple pathways involved in the nervous system and inflammation. Protein-protein interaction (PPI) network analysis and molecular complex detection (MCODE) analysis yielded 10 hub genes, including AKT1, ADORA1, BCL2, CREB1, IL6, JUN, RELA, STAT3, TNF, and TP53. Results from weighted correlation network analysis (WGCNA) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of insomnia-related transcriptome data from peripheral blood mononuclear cells (PBMCs) showed that a sleep cocktail may also ease insomnia via regulating the inflammatory response. Molecular docking results reveal good affinity of Sleep Cocktail to 9 selected key targets. It is noteworthy that the crucial target HSP90AA1 binds to melatonin most stably, which was further validated by MD simulation.

The Influence of Social Dynamics on Biological Aging and the Health of Historically Marginalized Populations: A Biopsychosocial Model for Health Disparities

Historically marginalized populations are susceptible to social isolation resulting from their unique social dynamics; thus, they incur a higher risk of developing chronic diseases across the course of life. Research has suggested that the cumulative effect of aging trajectories per se, across the lifespan, determines later-in-life disease risks. Emerging evidence has shown the biopsychosocial effects of social stress and social support on one's wellbeing in terms of inflammation. Built upon previous multidisciplinary findings, here, we provide an overarching model that explains how the social dynamics of marginalized populations shape their rate of biological aging through the inflammatory process. Under the framework of social stress and social support theories, this model aims to facilitate our understanding of the biopsychosocial impacts of social dynamics on the wellbeing of historically marginalized individuals, with a special emphasis on biological aging. We leverage this model to advance our mechanistic understanding of the health disparity observed in historically marginalized populations and inform future remediation strategies.

Associations between insomnia symptoms and inflammatory cytokines in adolescents with first-episode and recurrent major depressive disorder

BACKGROUND

Insomnia symptoms are often associated with increased levels of inflammatory biomarkers. However, such associations have not been adequately explored in adolescents with major depressive disorder (MDD). This study aimed to examine the associations between insomnia symptoms with inflammatory cytokines in adolescents with first-episode and recurrent MDD.

METHODS

From January to December 2021, this study included 164 adolescents with MDD and 76 healthy controls (HCs). The Center for Epidemiological Studies Depression Scale (CES-D) and the Insomnia Severity Index Scale (ISI) were used to assess depressive and insomnia symptoms, respectively. Also, plasma levels of interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-17 A and tumor necrosis factor-α (TNF-α) were measured.

RESULTS

The prevalence of mild, moderate and severe insomnia in adolescents with MDD was 40.24 %, 36.59 % and 6.71 %, respectively. The patients had higher levels of IL-1β, IL-6 and TNF-α than HCs (all p < 0.05). ISI score was positively correlated with CES-D score and levels of IL-1β, IL-6 and TNF-α in first-episode patients but not in recurrent patients. A further multivariate stepwise linear regression analysis showed that ISI score was independently associated with CES-D score (beta = 0.523, t = 5.833, p < 0.001) and TNF-α levels (beta = 0.254, t = 2.832, p = 0.006).

LIMITATIONS

The cross-sectional design leads to failure to make causal inferences.

CONCLUSION

Insomnia symptoms are common in adolescents with MDD and associated with elevated levels of inflammatory cytokines in first-episode patients. The findings suggest that inflammatory cytokines may relate to the pathogenesis of insomnia symptoms in adolescents with MDD, but further longitudinal studies are needed to explore the causal association between insomnia symptoms and inflammatory cytokines in MDD.

The causal associations of altered inflammatory proteins with sleep duration, insomnia and daytime sleepiness

STUDY OBJECTIVES

Growing evidence linked inflammation with sleep. This study aimed to evaluate the associations and causal effects of sleep traits including insomnia, excessive daytime sleepiness (EDS), and sleep duration (short: <7 h; normal: 7-9 h; long: ≥9 h), with levels of C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), and interleukins.

METHODS

Standard procedures of quantitative analysis were applied to estimate the expression differences for each protein in compared groups. Then, a two-sample Mendelian randomization (MR) analysis was performed to explore their causal relationships with published genome-wide association study summary statistics. The inverse-variance weighted was used as the primary method, followed by several complementary approaches as sensitivity analyses.

RESULTS

A total of 44 publications with 51 879 participants were included in the quantitative analysis. Our results showed that the levels of CRP, interleukin-1β (IL-1β), IL-6, and TNF-α were higher from 0.36 to 0.58 (after standardization) in insomnia compared with controls, while there was no significant difference between participants with EDS and controls. Besides, there was a U/J-shaped expression of CRP and IL-6 with sleep durations. In MR analysis, the primary results demonstrated the causal effects of CRP on sleep duration (estimate: 0.017; 95% confidence intervals [CI], [0.003, 0.031]) and short sleep duration (estimate: -0.006; 95% CI, [-0.011, -0.001]). Also, IL-6 was found to be associated with long sleep duration (estimate: 0.006; 95% CI, [0.000, 0.013]). These results were consistent in sensitivity analyses.

CONCLUSIONS

There are high inflammatory profiles in insomnia and extremes of sleep duration. Meanwhile, elevated CRP and IL-6 have causal effects on longer sleep duration. Further studies can focus on related upstream and downstream mechanisms.

Sleep disturbance, but not depression severity, is associated with inflammation in children and adolescents

STUDY OBJECTIVES

We aimed to examine the association between self-rated and clinician-rated sleep disturbances and C-reactive protein (CRP), an objective marker of inflammation, in pediatric depression.

METHODS

Two hundred fifty-six children and adolescents (15.2 ± 1.6 y, 72.3% female) with moderate to severe symptoms of depression participated in the study. Sleep disturbances were assessed by self-reports (Insomnia Severity Index) and clinician ratings (Kiddie-Schedule for Affective Disorder and Schizophrenia), inflammation by plasma CRP levels.

RESULTS

Higher levels of CRP correlated positively with clinician-rated middle insomnia and hypersomnia. After adjusting for control variables (body mass index, tobacco, alcohol, stress, age, sex, antidepressants, sleep medication, depression severity), regression models confirmed the significant association of clinician-rated hypersomnia and middle insomnia symptoms with elevated CRP levels. In the adjusted regression models, other clinician-rated manifestations of sleep disturbance (eg, initial insomnia) and insomnia self-ratings were not significantly associated with CRP. Body mass index correlated positively with CRP, but body mass index had no mediating effect on the associations between sleep disturbances and CRP. We did not find an association between depression severity, assessed by the Children's Depression Rating Scale-Revised, and CRP.

CONCLUSIONS

Results of the present study indicate a significant association of hypersomnia and middle insomnia symptoms with CRP in pediatric depression, not linked to alterations in the body mass index.

CITATION

Strumberger MA, Häberling I, Emery S, et al. Sleep disturbance, but not depression severity, is associated with inflammation in children and adolescents. J Clin Sleep Med. 2023;19(10):1775-1784.

Heat of the night: sleep disturbance activates inflammatory mechanisms and induces pain in rheumatoid arthritis

Sleep has a homeostatic role in the regulation of the immune system and serves to constrain activation of inflammatory signalling and expression of cellular inflammation. In patients with rheumatoid arthritis (RA), a misaligned inflammatory profile induces a dysregulation of sleep-wake activity, which leads to excessive inflammation and the induction of increased sensitivity to pain. Given that multiple biological mechanisms contribute to sleep disturbances (such as insomnia), and that the central nervous system communicates with the innate immune system via neuroendocrine and neural effector pathways, potential exists to develop prevention opportunities to mitigate the risk of insomnia in RA. Furthermore, understanding these risk mechanisms might inform additional insomnia treatment strategies directed towards steering and reducing the magnitude of the inflammatory response, which together could influence outcomes of pain and disease activity in RA.

Inflammatory hypotheses of sleep disturbance - depression link: Update and research agenda

Studies in human and experimental animal models support a role of inflammation in the aetiology of depression, yet the precise role played by sleep disturbance (i.e., difficulties falling or maintaining sleep) is poorly understood. Consistent evidence from prospective epidemiological studies suggests sleep disturbance as a predictor of major depression episodes and depression recurrence. In parallel, up to 20% of individuals with sleep disturbance have low-grade peripheral inflammation (i.e., CRP>3 mg/l), and preliminary longitudinal evidence showed that sleep disturbance may even predict the levels of inflammation. Therefore, it is possible that sleep disturbance may increase inflammation, which in turn may contribute (i.e., mediate) to the onset - or worsening - of depression. Alternatively, sleep disturbance may serve as a vulnerability factor and increase the risk of developing depressive symptoms when facing an immune challenge. The aim of this review was to summarise the state of the science on the role of sleep disturbance in contributing to depression-related inflammation. A research agenda is also proposed to advance the study of sleep disturbance in the psychoneuroimmunology of depression.

Poor sleep quality, insomnia, and short sleep duration before infection predict long-term symptoms after COVID-19

BACKGROUND

Millions of COVID-19 survivors experience a wide range of long-term symptoms after acute infection, giving rise to serious public health concerns. To date, few risk factors for post-COVID-19 conditions have been determined. This study evaluated the role of pre-infection sleep quality/duration and insomnia severity in the incidence of long-term symptoms after COVID-19.

MATERIAL AND METHODS

This prospective study involved two assessments (April 2020 and 2022). At the baseline (April 2020), sleep quality/duration and insomnia symptoms in participants without current/prior SARS-CoV-2 infection were measured using the Pittsburgh Sleep Quality Index (PSQI) and the Insomnia Severity Index (ISI). At the follow-up (April 2022), we asked a group of COVID-19 survivors to retrospectively evaluate the presence of twenty-one symptoms (psychiatric, neurological, cognitive, bodily, and respiratory) that have been experienced one month (n = 713, infection in April 2020-February 2022) and three months after COVID-19 (n = 333, infection in April 2020-December 2021). In April 2022, participants also reported how many weeks passed to fully recover from COVID-19. Zero-inflated negative binomial models were used to estimate the effect of previous sleep on the number of long-term symptoms. Binomial logistic regressions were performed to evaluate the association between sleep variables, the incidence of each post-COVID-19 symptom, and the odds of recovery four/twelve weeks after infection.

RESULTS

Analyses highlighted a significant effect of pre-infection sleep on the number of symptoms one/three months after COVID-19. Previous higher PSQI and ISI scores, and shorter sleep duration significantly increased the risk of almost every long-term symptom at one/three months from COVID-19. Baseline sleep problems were also associated with longer recovery times to return to the pre-infection daily functioning level after COVID-19.

CONCLUSIONS

This study suggested a prospective dose-dependent association between pre-infection sleep quality/quantity and insomnia severity with the manifestation of post-COVID-19 symptoms. Further research is warranted to determine whether preventively promoting sleep health may mitigate the COVID-19 sequelae, with substantial public health and societal implications.

Mechanism of the association between sleep quality and mortality in middle-aged and older adults: A prospective study analysis of the UK Biobank

BACKGROUND

Although sleep quality is known to be associated with mortality, how poor sleep quality contributes to an increased risk of mortality is still unknown. We aimed to examine whether lifestyle, psychosocial and biological factors mediate the association.

METHODS

205,654 participants from UK Biobank were used for the analysis. The outcome was all-cause, cardiovascular disease (CVD) and cancer mortality by February 2022. Exposure was assessed by a sleep score consisting of five sleep behaviors at baseline. Lifestyle, psychosocial, and biological factors are regarded as potential mediators. Mediation analysis based on Cox proportional hazards models was performed.

RESULTS

Poor sleep quality was associated with a higher risk of all-cause (Hazard Ratio [HR] = 1.098; 95% CI: 1.058-1.140), CVD (HR = 1.139; 95% CI: 1.045-1.243) and cancer mortality (HR = 1.095; 95% CI: 1.040-1.152). Lifestyle mediators (smoking, physical activity, sedentary, BMI and diet) could explain between 2.6% and 34.0% of the increased risk of all-cause mortality in individuals with poor sleep quality. Self-reported health, frailty, depression, and loneliness were significant psychosocial mediators of this association pathway. About one-fifth of the association can be explained by the biological role of CRP. Similar mediating patterns were observed for CVD and cancer mortality.

LIMITATIONS

Both exposure and mediators were measured at baseline, so the possibility of reverse causality cannot be ruled out.

CONCLUSIONS

Poor sleep quality is associated with an increased risk of death through a combination of lifestyle, psychosocial and biological pathways. Adopting healthy lifestyles and staying psychosocial well-being are cost-effective interventions to lower the risk of death.

The Bi-directional Relationship Between Sleep and Inflammation in Muscular Dystrophies: A Narrative Review

Muscular dystrophies vary in presentation and severity, but are associated with profound disability in many people. Although characterised by muscle weakness and wasting, there is also a very high prevalence of sleep problems and disorders which have significant impacts on quality of life in these individuals. There are no curative therapies for muscular dystrophies, with the only options for patients being supportive therapies to aid with symptoms. Therefore, there is an urgent need for new therapeutic targets and a greater understanding of pathogenesis. Inflammation and altered immunity are factors which have prominent roles in some muscular dystrophies and emerging roles in others such as type 1 myotonic dystrophy, signifying a link to pathogenesis. Interestingly, there is also a strong link between inflammation/immunity and sleep. In this review, we will explore this link in the context of muscular dystrophies and how it may influence potential therapeutic targets and interventions.

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.

Racial/ethnic variations in inflammatory markers: exploring the role of sleep duration and sleep efficiency

Individuals from minoritized racial/ethnic groups have higher levels of circulating inflammatory markers. However, the mechanisms underlying these differences remain understudied. The objective of this study was to examine racial/ethnic variations in multiple markers of inflammation and whether impaired sleep contributes to these racial/ethnic differences. Nurses from two regional hospitals in Texas (n = 377; 71.62% White; 6.90% Black; 11.14% Hispanic, 10.34% Asian; mean age = 39.46; 91.78% female) completed seven days of sleep diaries and actigraphy to assess mean and variability in total sleep time (TST) and sleep efficiency (SE). On day 7, blood was drawn to assess 4 inflammatory markers: C-reactive protein (CRP), Interleukin-6 (IL-6), Interleukin-1 beta (IL-1β), and tumor necrosis factor-alpha (TNF-α). Results from regression models showed differences in inflammatory markers by race/ethnicity, adjusting for age and gender. The associations between sleep parameters and inflammatory markers also varied by race/ethnicity. Among White nurses, lower mean and greater variability in actigraphy-determined TST and greater variability in diary-determined TST were associated with higher levels of IL-6. Among Black nurses, lower mean diary-determined SE was associated with higher levels of IL-6 and IL-1β. Among Hispanic nurses, greater diary-determined mean TST was associated with higher CRP. Among Asian nurses, greater intraindividual variability in actigraphy-determined SE was associated with lower CRP. Among nurses, we did not find racial/ethnic disparities in levels of inflammation. However, analyses revealed differential relationships between sleep and inflammatory markers by race/ethnicity. Results highlight the importance of using a within-group approach to understand predictors of inflammatory markers.

Sleep disturbance and activation of cellular and transcriptional mechanisms of inflammation in older adults

BACKGROUND

Sleep disturbance, including poor subjective sleep quality and insomnia disorder, is common in older adults and associated with increases in age-related morbidity risk. Accumulating evidence implicates inflammation as an underlying mechanism. In two complementary studies, we examined whether sleep disturbance is associated with activation of cellular and transcriptional mechanisms of inflammation in older adults.

METHODS

Study 1 examined whether healthy older adults with poor subjective sleep quality (n = 62), compared to those with good subjective sleep quality (n = 101), differed in monocytic production of interleukin (IL)-6 and/or tumor necrosis factor (TNF)-α following stimulation with lipopolysaccharide. Study 2 examined whether older adults with insomnia disorder (n = 17), compared to those without insomnia disorder (n = 25), differed in the regulation of transcription factors (TFs) related to immune activation (i.e., nuclear factor-κB/Rel family), sympathetic nervous system (SNS) activity (i.e., cAMP-response element-binding protein), hypothalamic-pituitary-adrenal (HPA) axis activity (i.e., glucocorticoid receptor) and anti-viral responses (i.e., interferon-regulatory factor/interferon-stimulated response element) assessed in peripheral blood mononuclear cells.

RESULTS

In Study 1, older adults with poor subjective sleep quality, compared to those with good subjective sleep quality, showed higher percentages of stimulated monocytes producing IL-6 only (25.4 ± 16.8 % vs 20.4 ± 13.9 %; p < 0.05, η_p² = 0.03), producing TNF-α only (37.6 ± 13.1 % vs 31.2 ± 14.3 %; p < 0.01, η_p² = 0.05), and co-producing IL-6/TNF-α simultaneously (17.8 ± 11.7 % vs 13.9 ± 9.6 %; p < 0.05, η_p² = 0.03). In Study 2, older adults with insomnia disorder, compared to those without insomnia disorder, showed higher TF activity related to immune activation (p's < 0.05) and SNS function (p's < 0.001), along with lower TF activity related to HPA axis function (p's < 0.05).

CONCLUSION

In older adults, poor subjective sleep quality and insomnia diagnosis are associated with increases in monocytic cytokine production and changes in TF activity related to immune activation, SNS function, and HPA axis function. Activation of markers of cellular and transcriptional inflammation might contribute to the link between sleep disturbance and age-related morbidity risk.

Longitudinal association between sleep disturbance and inflammation, and the role of positive affect

Previous longitudinal evidence suggested that sleep disturbance (i.e., difficulties in sleep onset and sleep maintenance) may be longitudinally associated with systemic inflammation, which is involved in the pathophysiology of mental and somatic illness. The mechanisms underlying this association, however, remain largely unexplored. In the context of health psychology, a substantial body of literature showed that positive affect may have a favourable impact on immune and inflammatory response and buffer the proinflammatory effects of stress. Therefore, the aim of this study was to assess whether subjective sleep disturbance is longitudinally associated with serum high sensitivity C-reactive protein (hs-CRP), a marker of systemic inflammation, and whether this association is mediated by a decrease in positive affect. The data of 1894 participants aged 64.11 ± 8.02 years from the English Longitudinal Study of Ageing (ELSA) across three waves of data collection were analysed. Self-reported sleep disturbance was assessed in 2008-2009, (wave 4), positive affect was assessed in 2010-2011 (wave 5), and hs-CRP was assessed in 2012-2013 (wave 6). Path analysis adjusted for health-related variables including depressive symptoms, cardiovascular disease, BMI, smoking, alcohol consume, and drug intake showed a significant direct effect of sleep disturbance to positive affect; positive affect directly predicted hs-CRP. Lastly, an indirect effect between sleep disturbance to hs-CRP through the mediating role of positive affect emerged. The findings suggest that sleep onset and sleep maintenance difficulties may be associated with inflammation through the mediation of low positive affect. The clinical significance of the findings should be further explored.

Prevalence and risk factors of sleep disturbance in adults with underlying health conditions during the ongoing COVID-19 pandemic

To determine the prevalence of sleep disturbance during the coronavirus disease 2019 (COVID-19) pandemic among US adults who are more vulnerable to complications because of age and co-morbid conditions, and to identify associated sociodemographic and psychosocial factors. Cross-sectional survey linked to 3 active clinical trials and 2 cohort studies, conducted between 11/30/2020 and 3/3/2021. Five academic internal medicine practices and 2 federally qualified health centers. A total of 715 adults ages 23 to 91 years living with one or more chronic conditions. A fifth (20%) of participants reported poor sleep. Black adults were twice as likely to report poor sleep compared to Whites. Self-reported poor physical function (51%), stress (42%), depression (28%), and anxiety (36%) were also common and all significantly associated with poor sleep. Age ≥70 years and having been vaccinated for COVID-19 were protective against poor sleep. Sex, education, income, alcohol use, and employment status were not significantly associated with sleep quality. In this diverse sample of adults with chronic conditions, by race, ethnicity, and socioeconomic status, disparities in sleep health amid the ongoing pandemic were apparent. Worse physical function and mental health were associated with poor sleep and should be considered targets for health system interventions to prevent the many subsequent consequences of disturbed sleep on health outcomes. Measurements: self-reported sleep quality, physical function, stress, depression, and anxiety.

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.

Alleviating insomnia should decrease the risk of irritable bowel syndrome: Evidence from Mendelian randomization

Background: Associations have been reported between sleep and irritable bowel syndrome (IBS). However, whether there exists a causation between them is still unknown.

Methods: We employed the Mendelian randomization (MR) design to explore the causal relationship between sleep and IBS. All genetic associations with sleep-related traits reached genome-wide significance (p-value < 5 × 10-8). The genetic associations with IBS were obtained from two independent large genome-wide association studies (GWAS), where non-FinnGen GWAS was in the discovery stage and FinnGen GWAS was in the validation stage. Primarily, the inverse-variance weighted method was employed to estimate the causal effects, and a meta-analysis was performed to combine the MR estimates.

Results: In the discovery, we observed that genetic liability to the “morning” chronotype could lower the risk of IBS [OR = 0.81 (0.76, 0.86)]. Also, the genetic liability to insomnia can increase the risk of IBS [OR = 2.86 (1.94, 4.23)] and such causation was supported by short sleep duration. In the validation stage, only insomnia displayed statistical significance [OR = 2.22 (1.09, 4.51)]. The meta-analysis suggested two genetically-determined sleep exposures can increase the risk of IBS, including insomnia [OR = 2.70 (1.92, 3.80)] and short sleep duration [OR = 2.46 (1.25, 4.86)]. Furthermore, the multivariable MR analysis suggested insomnia is an independent risk factor for IBS after adjusting for chronotype [OR = 2.32 (1.57, 3.43)] and short sleep duration [OR = 1.45 (1.13, 1.85)]. IBS cannot increase the risk of insomnia in the reverse MR analysis.

Conclusion: Genetic susceptibility to insomnia can increase the risk of IBS, and improving sleep quality, especially targeting insomnia, can help to prevent IBS.

Why Sleep is Key: Poor Sleep Quality is a Mechanism for the Bidirectional Relationship between Major Depressive Disorder and Generalized Anxiety Disorder Across 18 Years

BACKGROUND

Generalized anxiety disorder (GAD) and major depressive disorder (MDD) reliably precede and predict one another. However, there is insufficient data on mediators through which the longitudinal GAD-MDD association unfold. Based on insomnia theories, such as the hyperarousal model of sleep, we tested the degree to which poor global sleep quality functioned as a mediator of the prospective bidirectional anxiety-depression relationship.

METHOD

Participants were 3,294 community-dwelling adults who partook in three measurement waves nine years apart. The Composite International Diagnostic Interview-Short Form assessed GAD and MDD in-person at baseline (Time 1 [T1]), Time 2 (T2; nine years after T1), and 18 years later (T3). T2 global sleep quality was measured using the multiple-domain Pittsburgh Sleep Quality Index self-report at T2. We used longitudinal structural equation modeling mediation analyses.

RESULTS

Analyses showed that higher T1 MDD and GAD severity individually predicted lower T2 global sleep quality (Cohen's d = -0.561 to -0.480) and less T2 global sleep quality, thereby forecasted both higher T3 MDD and GAD (d = -0.275 to -0.190). Poorer T2 global sleep quality significantly mediated the T1 GAD-T3 MDD relation, explaining 41% of the association. Worse global sleep quality at T2 also significantly mediated the T1 MDD-T3 GAD association, mediating 11% of the T1 MDD-T3 GAD pathway. The results remained similar after controlling for multiple sociodemographic and clinical variables.

CONCLUSIONS

Findings offer evidence for transdiagnostic theories of sleep and insomnia. Theoretical and clinical implications, such as prioritizing sleep improvement in cognitive-behavioral therapies, are also discussed.

Factors Associated With Myocardial Infarction Reoccurrence

BACKGROUND

As recurrent myocardial infarctions (MIRs) constitute almost a third of the annual incidence of myocardial infarction, identifying the traditional and novel variables related to MIR is important.

OBJECTIVE

The aim of this study was to examine modifiable cardiac risks, adiposity, symptoms associated with inflammation (fatigue, depression, sleep) and inflammatory cytokines, and MIR by sex and race.

METHODS

Using a cross-sectional descriptive design, we recruited a convenience sample of adults (N = 156) discharged with first myocardial infarction or had MIR in the last 3 to 7 years. Surveys measured demographics, cardiac risk factors, depression, sleep, and fatigue. Anthropometric measures and cytokines tumor necrosis factor-α, interleukin-6, and high-sensitivity C-reactive protein (hsCRP) were obtained. A maximum likelihood regression was calculated to predict MIR.

RESULTS

The sample included 57% male and 30% Black participants, and the mean (SD) age was 65 (12) years. The hsCRP was the only cytokine related to symptoms: fatigue ( r = 0.309, P < .001) and depression ( r = 0.255, P = .002). An MIR was not associated with race despite White participants reporting better sleep ( t146 = -3.25, P = .002), lower body mass index ( t154 = -3.49, P = .001), and fewer modifiable risk factors ( t152 = -2.05, P = .04). An MIR was associated with being male, higher hsCRP and tumor necrosis factor-α levels ( P < .001), and higher inflammatory symptoms of fatigue ( P = .04), depression ( P = .01), and poor sleep ( P < .001).

CONCLUSION

Further examination of biomarkers to understand the mechanisms associated with inflammatory symptoms of fatigue, depression, and poor sleep and MIR is needed.

Sleep, Positive Affect, and Circulating Interleukin-6 in Women With Temporomandibular Joint Disorder

OBJECTIVE

Systemic inflammation is commonly observed in idiopathic chronic pain conditions, including temporomandibular joint disorder (TMD). Trait positive affect (PA) is associated with lower inflammation in healthy controls, but those effects may be threatened by poor sleep. The associations between PA with proinflammatory cytokine activity and potential moderation by sleep in chronic pain are not known. We thus investigated the association between PA and circulating interleukin-6 (IL-6) and moderation of that association by sleep in a sample of women with TMD and sleep difficulties.

METHODS

Participants (n = 110) completed the insomnia severity index and provided blood samples at five intervals throughout an evoked pain testing session. They then completed a 14-day diary assessing sleep and affect, along with wrist actigraphy.

RESULTS

There was not a significant main effect of PA on resting or pain-evoked IL-6 (b = 0.04, p = .33). Diary total sleep time (b = -0.002, p = .008), sleep efficiency (b = -0.01, p = .005), sleep onset latency (b = 0.006, p = .010), and wake after sleep onset (b = 0.003, p = .033) interacted with PA to predict IL-6, such that PA inversely predicted IL-6 at higher levels of total sleep time and sleep efficiency and at lower levels of sleep onset latency and wake after sleep onset. Surprisingly, when sleep was poor, PA predicted greater IL-6.

CONCLUSIONS

The potential salutary effects of PA on resting IL-6 erode when sleep is poor, underscoring the importance of considering sleep in conceptual and intervention models of TMD.

Symptoms of obstructive sleep apnea are associated with less frequent exercise and worse subjective cognitive function across adulthood

STUDY OBJECTIVES

To determine whether subjective measures of exercise and sleep are associated with cognitive complaints and whether exercise effects are mediated by sleep.

METHODS

This study analyzed questionnaire data from adults (18-89) enrolled in a recruitment registry. The Cognitive Function Instrument (CFI) assessed cognitive complaints. Medical Outcomes Study Sleep Scale (MOS-SS) subscales and factor scores assessed sleep quality, daytime sleepiness, nighttime disturbance, and insomnia and obstructive sleep apnea (OSA)-like symptoms. Exercise frequency was defined as the weekly number of exercise sessions. Exercise frequency, MOS-SS subscales, and factor scores were examined as predictors of CFI score, adjusting for age, body mass index, education, sex, cancer diagnosis, antidepressant usage, psychiatric conditions, and medical comorbidities. Analyses of covariance examined the relationship between sleep duration groups (short, mid-range, and long) and CFI score, adjusting for covariates. Mediation by sleep in the exercise-CFI score relationship was tested.

RESULTS

Data from 2106 adults were analyzed. Exercise and MOS-SS subscales and factor scores were associated with CFI score. Higher Sleep Adequacy scores were associated with fewer cognitive complaints, whereas higher Sleep Somnolence, Sleep Disturbance, Sleep Problems Index I, Sleep Problems Index II, and factor scores were associated with more cognitive complaints. MOS-SS subscales and factor scores, except Sleep Disturbance and the insomnia factor score, mediated the association between exercise and cognitive complaints.

CONCLUSIONS

The relationship between exercise frequency and subjective cognitive performance is mediated by sleep. In particular, the mediation effect appears to be driven by symptoms possibly suggestive of OSA which are negatively associated with exercise engagement, sleep quality, daytime sleepiness, and subjective cognitive performance.

Association of Poor Sleep With Depressive and Anxiety Symptoms by HIV Disease Status: Women's Interagency HIV Study

BACKGROUND

Sleep disturbances are prevalent in women living with HIV (WLWH) and can affect mental health and overall quality of life. We examined the prevalence and predictors of poor sleep quality in a US cohort of WLWH and HIV-uninfected controls and the relationship between sleep quality and mental health symptom burden stratified by HIV disease status (viremic WLWH, aviremic WLWH, and HIV-uninfected women).

METHODS

Sleep quality was assessed using the Pittsburgh Sleep Quality Index in 1583 (400 viremic WLWH, 723 aviremic WLWH, and 460 HIV-uninfected women) Women's Interagency HIV Study participants. Depressive and anxiety symptoms were concurrently assessed using the Center for Epidemiological Studies-Depression (CES-D) scale and General Anxiety Disorder (GAD-7) scale. Associations between poor sleep quality (global Pittsburgh Sleep Quality Index >5) and both high depressive (CES-D ≥16) and anxiety (GAD-7 ≥10) symptoms were each assessed by HIV disease status using multivariable logistic regression models.

RESULTS

Prevalence of poor sleep quality in the overall sample was 52%, differed by HIV disease status (P = 0.045), and was significantly associated with high depressive and anxiety symptoms in (1) viremic WLWH, (2) aviremic WLWH, and (3) HIV-uninfected women [CES-D: (1) adjusted odds ratio (aOR) = 7.50, 95% confidence interval (CI): 4.10 to 13.7; (2) aOR = 4.54, 95% CI: 3.07 to 6.73; and (3) aOR = 6.03, 95% CI: 3.50 to 10.4; GAD-7: (1) aOR = 5.20; 95% CI: 2.60 to 10.4, (2) aOR = 6.03; 95% CI: 3.67 to 9.91, and (3) aOR = 6.24; 95% CI: 3.11 to 12.6].

CONCLUSIONS

Poor sleep quality is highly prevalent, as is mental health symptom burden, among WLWH and HIV-uninfected controls. Future longitudinal studies are necessary to clarify the directionality of the relationship.

Loneliness and multiple health domains: associations among emerging adults

Emerging adults (18–25 years), particularly racially/ethnically diverse and sexual and gender minority populations, may experience loneliness following major life transitions. How loneliness relates to health and health disparities during this developmental period is not well understood. We examine associations of loneliness with physical (self-rated health), behavioral (alcohol/marijuana consequences; nicotine dependence), and health behavior outcomes (weekday and weekend sleep; trouble sleeping), and investigate moderating effects by sex, race/ethnicity, and sexual/gender minority (SGM) status. Adjusted models using cross-sectional data from 2,534 emerging adults, predominantly in California, examined associations between loneliness and each outcome and tested interactions of loneliness with sex, race/ethnicity, and SGM status. Higher loneliness was significantly associated with worse self-rated health, higher marijuana consequences, less weekday sleep, and greater odds of feeling bothered by trouble sleeping. None of the interactions were significant. Findings suggest that interventions to reduce loneliness may help promote healthy development among emerging adults across subgroups.

Insomnia and other sleep disorders in dermatology patients: A questionnaire-based study with 634 patients

Insufficient sleep duration and quality are associated with various adverse health outcomes. Whereas sleep disorders have been studied in a few skin conditions, data in a more comprehensive dermatology population are lacking. We sought to describe the prevalence, causes, and consequences of sleep disorders in dermatology patients. In this cross-sectional, single-center study, dermatology patients completed a questionnaire addressing skin-related and non-skin-related health, sleep behavior, causes, and consequences of sleep disorders. According to the Regensburg Insomnia Scale, 27.92% of the 634 participants had insomnia (177 of 634 patients). Of these 177 patients, 115 (64.97%) were subjectively sleep disturbed, with skin-related causes accounting for 55.65% (64 of 115 patients), non-skin-related accounting for 33.04% (38 of 115 patients), and combined accounting for 11.30% (13 of 115 patients). Itch was the leading cause of skin-related sleep disorders (64.49%, 50 of 77 patients), followed by skin-related pain (55.84%, 43 of 77 patients) and skin-related fearful thoughts (54.55%, 42 of 77 patients). Sleep disorders reduced daytime performance in 68.70% (79 of 115 patients) and sleep quality of relatives in 20.87% (24 of 115 patients). The prevalence of insomnia among different diagnostic categories ranged from 20.31% to 50.00%. The most common strategy to improve sleep was taking sleep medication (57.39%, 66 of 115 patients). We conclude that sleep disorders are highly prevalent in dermatology patients, often leading to reduced daytime performance, impaired sleep among the patients' relatives, and increased use of substances.

Insomnia and inflammation in phase 1 of the clinical antipsychotic trials of intervention effectiveness study

Insomnia and inflammation are both common in schizophrenia. In the general population, insomnia is associated with inflammation. In n=519 subjects from the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) schizophrenia trial, terminal insomnia was investigated as an indicator of inflammation using non-parametric ANCOVA. After controlling for potential confounders, insomnia was significantly associated with higher blood IL-6 (F=4.12, p=0.007) and leptin (F=9.67, p<0.001) with large effect sizes (d=1.03 and d=0.79, respectively). Findings suggest that the assessment of insomnia is relevant to studies of inflammation in schizophrenia, and germane to trials of adjunctive hypnotics and anti-inflammatory agents in these patients.

Does the Interaction between Local and Systemic Inflammation Provide a Link from Psychology and Lifestyle to Tissue Health in Musculoskeletal Conditions?

Musculoskeletal conditions are known to involve biological, psychological, social and, often, lifestyle elements. However, these domains are generally considered in isolation from each other. This siloed approach is unlikely to be adequate to understand the complexity of these conditions and likely explains a major component of the disappointing effects of treatment. This paper presents a hypothesis that aims to provide a foundation to understand the interaction and integration between these domains. We propose a hypothesis that provides a plausible link between psychology and lifestyle factors with tissue level effects (such as connective tissue dysregulation/accumulation) in musculoskeletal conditions that is founded on understanding the molecular basis for interaction between systemic and local inflammation. The hypothesis provides plausible and testable links between mind and body, for which empirical evidence can be found for many aspects. We present this hypothesis from the perspective of connective tissue biology and pathology (fibrosis), the role of inflammation locally (tissue level), and how this inflammation is shaped by systemic inflammation through bidirectional pathways, and various psychological and lifestyle factors via their influence on systemic inflammation. This hypothesis provides a foundation for new consideration of the development and refinement of personalized multidimensional treatments for individuals with musculoskeletal conditions.

Endocrine and immunomodulatory effects of social isolation and loneliness across adulthood

Experimental and observational evidence agreed on two interconnected biological mechanisms responsible for the links between social isolation/loneliness and health: alterations in the activity of the hypothalamic-pituitary-adrenal (HPA) axis and compromised functioning of the innate immune system. However, most existing studies did not consider the simultaneous impact of social isolation and loneliness on biological outcomes. Further, they only assessed one biological outcome at a time and did not test any moderation by age, despite empirical and theoretical evidence supporting the plausibility of this hypothesis. To address these gaps in the literature, we tested the associations between two indicators of social isolation (living status and frequency of social contacts) and loneliness and daily cortisol secretion and two markers of systemic inflammation (C-reactive protein [CRP] and interleukin-6 [IL-6]) in a sample of adults aged between 25 and 75 years old. Data were drawn from the Midlife in the United States (MIDUS) Refresher study (N = 314). We found that, above and beyond loneliness, living alone was associated with a flattened diurnal cortisol slope (i.e., reduced changes in cortisol levels during waking hours that are indicative of a dysregulated HPA axis) and higher CRP levels. On the other hand, higher loneliness was associated with higher IL-6 levels, above and beyond our measures of social isolation. Loneliness did not mediate any of the effects of social isolation on either cortisol or CRP, and age did not moderate any of the relationships reported above. Our findings support the idea that social isolation and loneliness have unique and independent endocrine and immune effects despite being linked to each other. Understanding the specific biological pathways through which these aspects of social well-being exert their effects on health across the lifespan has critical consequences for both intervention development and public health policies.

Calcium Intake Is Inversely Related to Risk of Obesity among American Young Adults over a 30-Year Follow-Up

BACKGROUND

Calcium (Ca) is an essential nutrient that may play an important role in weight maintenance through its involvement in energy or lipid metabolism. However, little is known about the long-term associations of Ca intake with obesity risk.

OBJECTIVES

We aimed to prospectively examine the association between cumulative Ca intake and the incidence of obesity among American young adults over 30 y of follow-up.

METHODS

Participants were from the CARDIA (Coronary Artery Risk Development in Young Adults) study. A total of 4097 of 5115 black and white individuals aged 18-30 y at baseline in 1985-1986 were included in the current analysis. Dietary and supplemental Ca intake was assessed by the validated interview-based CARDIA diet history at baseline and exam years 7 and 20. Incident cases of obesity were identified when BMI was ≥30 kg/m2 for the first time since baseline. A survival analysis was performed using Cox proportional hazards regression models to estimate the HRs and corresponding 95% CIs for obesity incidence during follow-up.

RESULTS

During a 30-y follow-up (mean ± SD: 20 ± 10 y), 1675 participants developed obesity. Cumulative total Ca intake (dietary plus supplemental Ca) was inversely associated with incidence of obesity in multivariable-adjusted analysis [quintile (Q)5 (highest intake) compared with Q1 (lowest intake): HR: 0.68; 95% CI: 0.56, 0.82; P-trend < 0.01]. This inverse association persisted among Ca supplement users (Q5 compared with Q1: HR: 0.53; 95% CI: 0.40, 0.70; P-trend < 0.01), but was not seen among nonusers.

CONCLUSIONS

Following a cohort of Americans from young adulthood to midlife, an inverse association between calcium intake and obesity incidence was observed. Further studies are needed to confirm our findings.

Progressive increase in the complexity and translatability of rodent testing to assess space-radiation induced cognitive impairment

Ground-based rodent models have established that space radiation doses (approximately those that astronauts will be exposed to on a mission to Mars) significantly impair performance in a wide range of cognitive tasks. Over the last 40 years there has been a progressive increase in both the complexity and the translatability (to humans) of the cognitive tasks investigated. This review outlines technical and conceptual advances in space radiation rodent testing approaches, along with the advances in analytical approaches, that will make data from ground based studies more amenable to probabilistic risk analysis. While great progress has been made in determining the impact of space radiation on many advanced cognitive processes, challenges remain that need to be addressed prior to commencing deep space missions. A summary of on-going attempts to address existing knowledge gaps and the critical role that rodent studies will have in establishing the impact of space radiation on even more complex (human) cognitive tasks are presented and discussed.

Acute and chronic sleep deprivation in residents: Cognition and stress biomarkers

OBJECTIVES

Insufficient sleep affects circadian hormonal profiles and inflammatory markers and may modulate attention, executive functioning and decision-making. Medical professionals and specifically resident physicians, who are involved in long-term nightshift schedules during their post-graduate training, are prone to acute and chronic sleep deprivation and disruption, putting them at risk for making medical errors. The aim of the study was to evaluate the impact of chronic and acute-on-chronic sleep deprivation and disruption among residents on selected physiological and cognitive measures.

METHODS

Thirty-three medical and surgical residents were evaluated twice - at baseline and after a 26-hour shift. Eighteen young attending physicians who did not engage in nightshift schedules served as controls and were evaluated once. Measures included morning cortisol and high-sensitivity C-reactive protein (hs-CRP), computerised tests of attention and behaviour, the Behaviour Rating Inventory of Executive Function, a risk-taking questionnaire and the Pittsburgh Sleep Quality Index.

RESULTS

Residents, but not attendings, reported chronic sleep disruption and deprivation. Residents at baseline exhibited reduced morning cortisol levels and elevated hs-CRP levels, compared to attendings. Residents at baseline had impaired global executive function compared to attendings. A nightshift with acute sleep deprivation further reduced residents' executive function. Residents at baseline and after a nightshift demonstrated increased impulsivity and slower processing time than attendings. Residents and attendings did not differ in risk-taking tendencies which were assessed in a separate cohort.

CONCLUSIONS

In a real-life setting, resident physicians exhibit increased low-grade systemic inflammation (hs-CRP) and impaired HPA-axis function. Their chronic sleep curtailment is associated with greater impulsivity, slower cognitive processing, and impaired executive function. Future research is warranted to understand how improving working schedule by increasing sleep duration may minimise the short-term and potential long-term risks to physicians in training.

Sleep and social relationships in healthy populations: A systematic review

Over the past decade, research linking sleep and social relationships has burgeoned. Researchers across the globe are trying to understand whether the quality and quantity of our social relationships matter for sleep, and vice versa. We conducted a systematic review of the literature, identifying over 200 relevant articles examining sleep and social relationships in healthy populations. Here, we summarize our findings by reviewing 1) links between sleep and broad social ties across the lifespan, and 2) links between sleep and specific social relationships identified in the literature search, including romantic relationships, family relationships, and work relationships. Taken together, the literature provides evidence that the quality and presence of social relationships, especially our closest relationships, play a role in how we sleep. Likewise, sleep appears to influence our social bonds. However, the majority of work is correlational, limiting conclusions about the directionality of these effects. We conclude by synthesizing the findings, considering the limitations of the present literature, and identifying key future directions for this emerging area of research.

The Associations of Trajectory of Sleep Duration and Inflammation with Hypertension: A Longitudinal Study in China

BACKGROUND

Existing evidence suggested that sleep duration may be involved in hypertension; however, the conclusions were still controversial. This study aimed to examine the association of longitudinal trajectory of sleep duration with hypertension and to explore the role of the inflammation in such associations.

METHODS

A total of 3178 subjects over 30 years of age without hypertension were enrolled in 2004, and they were followed until 2009. Self-reported sleep duration was recorded, and inflammation was measured by highly sensitive C reactive protein (hs-CRP). Log-binomial regression models were applied to examine the association of sleep duration trajectory and inflammation with the risk of hypertension. The mediating effect of elevated hs-CRP was examined by the bootstrap and the process software.

RESULTS

The prevalence of persistent short (≤7 hours/day), normal (8-9 hours/day), and long (>9 hours/day) sleep duration over 5 years were 9.1%, 37.7%, and 2.3%, respectively. The incidence of hypertension was 26.6% during the follow-up period. Compared with those who persistently slept 8-9 hours/day from baseline to follow-up, those who persistently slept ≤7 hours/day, persistently slept ≥10 hours/day, and those whose sleep duration changed have higher risks of hypertension by 1.375-fold (95% CI: 1.121, 1.686), 1.557-fold (95% CI: 1.171, 2.069) and 1.299-fold (95% CI: 1.135, 1.487), respectively. In addition, persistently slept ≤7 hours/day was found to be associated with higher risk of inflammation (RR: 1.285, 95% CI: 1.008, 1.638). The mediation analysis did not find significant mediating effect of elevated CRP on the association between sleep duration trajectory and hypertension.

CONCLUSION

Experiencing both a short or long sleep duration, especially for a long time, could lead to higher risk of hypertension. Persistent exposure to short sleep duration was also associated with inflammation. However, the higher risk of hypertension caused by persistent short sleep duration does not seem to be directly mediated through inflammation.

Suicidal ideation among nurses: Unique and cumulative effects of different subtypes of sleep problems

BACKGROUND

Nurses have high rates of sleep problems, and higher risk of suicide than the general population. However, there is no empirical evidence showing the extent to which sleep problems among nurses are related to suicidal ideation.

METHODS

Multistage stratified cluster sampling was performed to recruit nurses from tertiary hospitals in Shandong, China. Item 9 of the Patient Health Questionnaire-9 was used to assess suicidal ideation. The Pittsburgh Sleep Quality Index was used to assess different subtypes of sleep problems.

RESULTS

Overall prevalence of suicidal ideation among the sample was 10.8%. Nurses with sleep problems were at high risk for suicidal ideation (^bOR = 1.79, 95% CI = 1.20-2.65). Among different sleep problem subtypes, only "cannot breathe comfortably" was independently related to suicidal ideation. Different subtypes of sleep problems had cumulative effects on suicidal ideation: the more subtypes of sleep problems nurses experienced, the higher the likelihood of suicidal ideation.

LIMITATIONS

The cross-sectional study design prevents inferring causation, and the use of self-report measures may lead to recall bias. Other physical/mental conditions, besides depression, were not assessed. Statistical power may have been insufficient due to the small sub-sample who reported suicidal ideation. Also, the generalizability of the results is limited, as the sample only comprised nurses in tertiary hospitals.

CONCLUSIONS

Nurses experiencing sleep problems were associated with increased likelihood of suicidal ideation. It may be beneficial to incorporate sleep problems into routine screening and intervention for suicide prevention in clinical practice.

Association of sleep duration and quality with elevated hs-CRP among healthy Korean adults

This study aimed to investigate the association of sleep duration and quality with high-sensitivity C-reactive protein (hs-CRP) among middle-aged and elderly Koreans. Among a total of 74,867 participants (25,069 men and 49,798 women) recruited for the Health Examinees (HEXA) study, adjusted geometric means of hs-CRP level were compared across categories of sleep duration (<6, 6–7, 8–9, and ≥10 hours) and sleep quality (difficulty in initiating sleep and maintaining sleep) using ANCOVA models. Odds ratios (ORs) and 95% confidence intervals (CIs) for elevated hs-CRP (>3 mg/L) associated with sleep characteristics were estimated using multivariable-adjusted logistic regression models. Men who slept ≥10 hours per day were significantly associated with elevated hs-CRP (OR = 1.47, 95% CI 1.11–1.95). Whereas in women, difficulty in initiating sleep (OR = 1.28, 95% CI 1.04–1.57 for “Always”), and maintaining sleep was significantly associated with elevated hs-CRP levels (OR = 1.13, 95% CI 1.02–1.26 for “Often”; OR = 1.11, 95% CI 0.97–1.28 for “Always”). Additionally, women who experienced poor sleep quality presented an elevated level of hs-CRP (OR = 1.13, 95% CI 1.03–1.23). Our findings suggest that excessive sleep duration and poor sleep quality are significantly associated with the elevated inflammatory marker, specifically hs-CRP. Further research is needed to examine the effect of sleep interventions focused on these factors.

Biopsychosocial factors associated to self-percepted sleep function in Brazilian elderly people: analysis of a national survey

BACKGROUND

Sleep is a dimension of well-being and health. Non-restful sleep is related to health dysfunctions, especially in vulnerable populations, considering that related factors change contextually. Thus, the objective of the present study was to measure the magnitude of the reduction in sleep restorative function (SRF) and related biopsychosocial factors in Brazilian elderly.

METHOD

Secondary data from the 2013 National Health Survey of cross-sectional design were analyzed. The sample consisted of individuals as from 60 years old. The outcome considered was the prevalence of reduced self-perceived sleep restorative function (SRF). Health and sleep characteristics, emotional behavior, lifestyle, social support, and urbanization were all investigated. The association with outcome was measured with the prevalence ratio (PR) and estimated with Cox regression, assuming α ≤ 0.05.

RESULTS

SRF was reduced by 29.2% (95%CI 27.2 - 30.6%). It is related to depression (PR = 3.37; 95%CI 2.87 - 3.97), insomnia/sleepiness (PR = 2.45; 95%CI 2.14 - 2.79); behavioral oscillation (PR = 1.75; 95%CI 1.53 - 1.99), negative health perception (PR = 1.50; 95%CI 1.23 - 1.82), computer and internet (PR = 1.44; 95%CI 1.01 - 2.07) and functional difficulty (PR = 1.13; 95%CI 1.01 - 1.27). Living in urban areas (PR = 1.32; 95%CI 1.14 - 1.52) and having a chronic condition (PR = 1.58; 95%CI 1.11 - 2.40) were only associated to the worst situation of reduced SRF.

CONCLUSION

The reduction in SRF affects one third of the elderly in Brazil and is closely related to biopsychosocial factors, requiring intersectoral public health promotion approaches.

Volunteering, Subjective Sleep Quality, and Chronic Inflammation: A 5-Year Follow-Up of the National Social Life, Health, and Aging Project

Studies indicate that the benefits of volunteering may extend to biological risk factors in disease development including chronic inflammation, though the pathway through which volunteer activity predicts chronic inflammation remains unclear. The current project focuses on the link between volunteering and C-reactive protein (CRP) as a measure of chronic inflammation, while paying a particular attention to sleep quality as a pathway. Using panel data from the National Social Life, Health, and Aging Project (N = 1,124), the present study examined whether sleep quality operates indirectly linking volunteer activity and CRP (indirect pathway), compensates for the lack of volunteerism (moderation-compensation), or regulates the benefits of volunteering on CRP (moderation-regulation). The findings suggest sleep quality as a compensatory pathway, in that sufficient sleep buffers the inflammatory effect of lack of volunteerism. The findings show that helping others may be beneficial for the helpers in terms of chronic inflammation and sleep quality as interconnected health outcomes.

Sleep and inflammation: partners in sickness and in health

The discovery of reciprocal connections between the central nervous system, sleep and the immune system has shown that sleep enhances immune defences and that afferent signals from immune cells promote sleep. One mechanism by which sleep is proposed to provide a survival advantage is in terms of supporting a neurally integrated immune system that might anticipate injury and infectious threats. However, in modern times, chronic social threats can drive the development of sleep disturbances in humans, which can contribute to the dysregulation of inflammatory and antiviral responses. In this Review, I describe our current understanding of the relationship between sleep dynamics and host defence mechanisms, with a focus on cytokine responses, the neuroendocrine and autonomic pathways that connect sleep with the immune system and the role of inflammatory peptides in the homeostatic regulation of sleep. Furthermore, I discuss the therapeutic potential of harnessing these reciprocal mechanisms of sleep-immune regulation to mitigate the risk of inflammatory and infectious diseases.