Increased nocturnal interleukin-6 excretion in patients with primary insomnia: a pilot study

Gut microbiota and sleep: Interaction mechanisms and therapeutic prospects

Sleep is crucial for wellness, and emerging research reveals a profound connection to gut microbiota. This review explores the bidirectional relationship between gut microbiota and sleep, exploring the mechanisms involved and the therapeutic opportunities it presents. The gut-brain axis serves as a conduit for the crosstalk between gut microbiota and the central nervous system, with dysbiosis in the microbiota impairing sleep quality and vice versa. Diet, circadian rhythms, and immune modulation all play a part. Specific gut bacteria, like Lactobacillus and Bifidobacterium, enhance sleep through serotonin and gamma-aminobutyric acid production, exemplifying direct microbiome influence. Conversely, sleep deprivation reduces beneficial bacteria, exacerbating dysbiosis. Probiotics, prebiotics, postbiotics, and fecal transplants show therapeutic potential, backed by animal and human research, yet require further study on safety and long-term effects. Unraveling this intricate link paves the way for tailored sleep therapies, utilizing microbiome manipulation to improve sleep and health. Accelerated research is essential to fully tap into this promising field for sleep disorder management.

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 mediation effects of nightmares and depression between insomnia and suicidal ideation in young adults

Suicide is prevalent among young adults, and epidemiological studies indicate that insomnia, nightmares, and depression are significantly associated with a high incidence of suicidal ideation (SI). However, the causal relationship between these factors and SI remains unclear. Therefore, the purpose of this study was to examine the association between nightmares and depression and insomnia and SI in young adults, as well as to develop a mediation model to investigate the causal relationship between insomnia, nightmare, depression, and SI. We assessed insomnia, nightmares, depression, and SI in 546 young adults using the Insomnia Severity Scale (ISI), Disturbing Dream and Nightmare Severity Scale (DDNSI), Depression Study Scale (CESD-20), and Columbia-Suicide Severity Rating Scale (C-SSRS). Using the Bootstrap method, the mediation effects of nightmares and depression between insomnia and SI were calculated. The results demonstrated that nightmares and depression fully mediated the relationship between insomnia and SI, including the chain-mediation of insomnia and SI between nightmare and depression with an effect value of 0.02, 95% CI 0.01-0.04, and depression as a mediator between insomnia and SI with an effect value of 0.22, 95% CI 0.15-0.29. This study found that depression and nightmares may be risk and predictive factors between insomnia and SI, which implies that the assessment and treatment of depression and the simple or linked effect of nightmares play crucial roles in preventing SI in young adults.

Sleep duration and mental health in young adults

BACKGROUND

The association between sleep duration and mental illness has been established in middle-aged and older populations, yet remains less explored in younger adults. Additionally, a common limitation to existing studies is the lack of statistical power to explore less common disorders. The purpose of this study was to examine sleep duration as a predictor for a range of mental disorders and well-being in a longitudinal sample of young adults.

METHODS

Data were derived from two waves (w1, w2) of the SHoT survey, which invited all full-time university and college students in Norway. The response rates were 34.4 % (n = 62,498) in 2021 (w1) and 35.1 % (n = 59,554) 2022 (w2). This study utilized a nested longitudinal sample from both w1 and w2, encompassing 21,289 students. Demographics, sleep duration (w1), and mental health (w2) were measured by self-report questionnaires. Sex-stratified linear regression models and log-link binomial regression analyses were employed to determine the proportion and calculate the risk ratios, respectively, for mental illness across different sleep duration categories.

RESULTS

The mean age of the sample was 24.8 years ± 4.5 years (w1). Students with shorter sleep durations, and to some degree longer sleep durations (illustrating a ᒐ-shaped association), exhibited a higher risk for all assessed mental disorders and well-being outcomes one year later, compared to students sleeping 8-9 h. The ᒐ-shaped trend was consistent for both female and male students.

CONCLUSION

Sleep duration appears to be a transdiagnostic marker for mental health in young adults.

A bidirectional Mendelian randomization study investigating the causal role between gut microbiota and insomnia

Background

It has emerged that disturbances of the gut microbiota (GM) are linked to insomnia. However, the causality of the observed associations remains uncertain.

Methods

We conducted a two-sample Mendelian randomization analysis based on genome-wide association study data to explore the possible causal link between GM and insomnia. The GM data were from the MiBioGen consortium, while the summary statistics of insomnia were obtained from the FinnGen consortium R9 release data. Cochran's Q statistics were used to analyze instrumental variable heterogeneity.

Results

According to the inverse variance weighted estimates, the family Ruminococcaceae (odds ratio = 1.494, 95% confidence interval:1.004-2.223, p = 0.047) and the genus Lachnospiraceae (odds ratio = 1.726, 95% confidence interval: 1.191-2.501, p = 0.004) play a role in insomnia risk. In contrast, the genus Flavonifractor (odds ratio = 0.596, 95% confidence interval: 0.374-0.952, p = 0.030) and the genus Olsenella (odds ratio = 0.808, 95% confidence interval: 0.666-0.980, p = 0.031) tended to protect against insomnia. According to the reverse MR analysis, insomnia can also alter GM composition. Instrumental variables were neither heterogeneous nor horizontal pleiotropic.

Conclusion

In conclusion, our Mendelian randomization study provides evidence of a causal relationship between GM and insomnia. The identified GM may be promising gut biomarkers and new therapeutic targets for insomnia. This investigation also provides a foundation for future studies examining the influence of GM on sleep disorders beyond insomnia, with potential implications for redefining the mechanisms governing sleep regulation.

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.

A two-phase, prescriptive comparative effectiveness study to optimize the treatment of co-occurring insomnia and depression with digital interventions

BACKGROUND

Insomnia and depression frequently co-occur. Significant barriers preclude a majority of patients from receiving first line treatments for both disorders in a sequential treatment episode. Although digital versions of cognitive behavioral therapy for insomnia (CBTI) and for depression (CBTD) hold some promise to meet demand, especially when paired with human support, it is unknown whether heterogeneity of treatment effects exist, such that some patients would be optimally treated with single or sequential interventions.

OBJECTIVE

Describe the protocol for a two-phase, prescriptive comparative effectiveness study to develop and evaluate an individualized intervention rule (IIR) for prescribing the optimal digital treament of co-occurring insomnia and depression.

METHODS

The proposed sample size is 2300 U.S. military veterans with insomnia and depression recruited nationally (Phase 1 = 1500; Phase 2 = 800). In each phase, the primary endpoint will be remission of both depression and insomnia 3 months following a 12-week intervention period. Phase 1 is a 5-arm randomized trial: two single digital interventions (CBT-I or CBT-D); two sequenced interventions (CBT-I + D or CBT-D + I); and a mood monitoring control condition. A cutting-edge ensemble machine learning method will be used to develop the IIR. Phase 2 will evaluate the IIR by randomizing participants with equal allocation to either the IIR predicted optimal intervention for that individual or by randomization to one the four CBT interventions.

RESULTS

Study procedures are ongoing. Results will be reported in future manuscripts.

CONCLUSION

The study will generate evidence on the optimal scalable approach to treat co-occurring insomnia and depression.

Exploring the mechanism of Suanzaoren decoction in treatment of insomnia based on network pharmacology and molecular docking

Objective: To explore the functional mechanisms of Suanzaoren decoction (SZRD) for treating insomnia using network pharmacology and molecular docking. Methods: The active ingredients and corresponding targets of SZRD were obtained from the Traditional Chinese Medicine Systems Pharmacology database, and then, the names of the target proteins were standardized using the UniProt database. The insomnia-related targets were obtained from the GeneCards, DisGeNET, and DrugBank databases. Next, a Venn diagram comprising the drug and disease targets was created, and the intersecting targets were used to draw the active ingredient-target network diagram using Cytoscape software. Next, the STRING database was used to build a protein-protein interaction network, followed by cluster analysis using the MCODE plug-in. The Database for Annotation, Visualization, Integrated Discovery (i.e., DAVID), and the Metascape database were used for Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. AutoDock Vina and Pymol software were used for molecular docking. Results: SZRD contained 138 active ingredients, corresponding to 239 targets. We also identified 2,062 insomnia-related targets, among which, 95 drug and disease targets intersected. The GO analysis identified 490, 62, and 114 genes related to biological processes, cellular components, and molecular functions, respectively. Lipid and atherosclerosis, chemical carcinogen-receptor activation, and neuroactive ligand-receptor interaction were the most common pathways in the KEGG analysis. Molecular docking demonstrated that the primary active components of SZRD for insomnia had good binding capabilities with the core proteins in PPI network. Conclusion: Insomnia treatment with SZRD involves multiple targets and signaling pathways, which may improve insomnia by reducing inflammation, regulating neurotransmitters.

Understanding neuron-glia crosstalk and biological clocks in insomnia

According to the World Health Organization, about one-third of the population experiences insomnia symptoms, and about 10-15% suffer from chronic insomnia, the most common sleep disorder. Sleeping difficulties associated with insomnia are often linked to chronic sleep deprivation, which has a negative health impact partly due to disruption in the internal synchronisation of biological clocks. These are regulated by clock genes and modulate most biological processes. Most studies addressing circadian rhythm regulation have focused on the role of neurons, yet glial cells also impact circadian rhythms and sleep regulation. Chronic insomnia and sleep loss have been associated with glial cell activation, exacerbated neuroinflammation, oxidative stress, altered neuronal metabolism and synaptic plasticity, accelerated age-related processes and decreased lifespan. It is, therefore, essential to highlight the importance of glia-neuron interplay on sleep/circadian regulation and overall healthy brain function. Hence, in this review, we aim to address the main neurobiological mechanisms involved in neuron-glia crosstalk, with an emphasis on microglia and astrocytes, in both healthy sleep, chronic sleep deprivation and chronic insomnia.

Highlighting the importance of healthy sleep patterns in the risk of adult asthma under the combined effects of genetic susceptibility: a large-scale prospective cohort study of 455 405 participants

BACKGROUND

Individuals with asthma usually have comorbid sleep disturbances; however, whether sleep quality affects asthma risk is still unclear. We aimed to determine whether poor sleep patterns could increase the risk of asthma and whether healthy sleep patterns could mitigate the adverse effect of genetic susceptibility.

METHODS

A large-scale prospective study was performed in the UK Biobank cohort involving 455 405 participants aged 38-73 years. Polygenic risk scores (PRSs) and comprehensive sleep scores, including five sleep traits, were constructed. A multivariable Cox proportional hazards regression model was used to investigate the independent and combined effects of sleep pattern and genetic susceptibility (PRS) on asthma incidence. Subgroup analysis across sex and sensitivity analysis, including a 5-year lag, different covariate adjustments and repeat measurements were performed.

RESULTS

A total of 17 836 individuals were diagnosed with asthma during over 10 years of follow-up. Compared with the low-risk group, the HRs and 95% CIs for the highest PRS group and the poor sleep pattern group were 1.47 (95% CI: 1.41 to 1.52) and 1.55 (95% CI: 1.45 to 1.65), respectively. A combination of poor sleep and high genetic susceptibility led to a twofold higher risk compared with the low-risk combination (HR (95% CI): 2.22 (1.97 to 2.49), p<0.001). Further analysis showed that a healthy sleep pattern was associated with a lower risk of asthma in the low, intermediate and high genetic susceptibility groups (HR (95% CI): 0.56 (0.50 to 0.64), 0.59 (0.53 to 0.67) and 0.63 (0.57 to 0.70), respectively). Population-attributable risk analysis indicated that 19% of asthma cases could be prevented when these sleep traits were improved.

CONCLUSIONS

Individuals with poor sleep patterns and higher genetic susceptibility have an additive higher asthma risk. A healthy sleep pattern reflected a lower risk of asthma in adult populations and could be beneficial to asthma prevention regardless of genetic conditions. Early detection and management of sleep disorders could be beneficial to reduce asthma incidence.

Insomnia symptoms and risk of bloodstream infections: prospective data from the prospective population-based Nord-Trøndelag Health Study (HUNT), Norway

Previous research suggests decreased immune function and increased risk of infections in individuals with insomnia. We examined the effect of insomnia symptoms on risk of bloodstream infections (BSIs) and BSI-related mortality in a population-based prospective study. A total of 53,536 participants in the second Norwegian Nord-Trøndelag Health Study (HUNT2) (1995-97) were linked to prospective data on clinically relevant BSIs until 2011. In Cox regression, we estimated hazard ratios (HRs) with 95% confidence intervals (CIs) for a first-time BSI and for BSI-related mortality (BSI registered ≤30 days prior to death) associated with insomnia symptoms. Compared with participants who reported "no symptoms", participants reporting having "difficulty initiating sleep" (DIS) often/almost every night had a HR for a first-time BSI of 1.14 (95% CI 0.96-1.34). Participants reporting "difficulties maintaining sleep" (DMS) often/almost every night had a HR of 1.19 (95% CI 1.01-1.40), whereas those having a feeling of "non-restorative sleep" once a week or more had a HR of 1.23 (95% CI 1.04-1.46). Participants frequently experiencing all three of the above symptoms had a HR of 1.39 (1.04-1.87), whilst those who had both DIS and DMS had a HR of 1.15 (0.93-1.41) and being troubled by insomnia symptoms to a degree that affected work performance was associated with a HR of 1.41 (95% CI 1.08-1.84). The HRs for BSI-related mortality suggest an increased risk with increasing insomnia symptoms, but the CIs are wide and inconclusive. We found that frequent insomnia symptoms and insomnia symptoms that affected work performance were associated with a weak positive increased risk of BSI.

Association between rest-activity rhythm and cognitive function in the elderly: The U.S. National Health and Nutrition Examination Survey, 2011-2014

BACKGROUND

Circadian rhythm plays an essential role in various physiological and pathological processes related to cognitive function. The rest-activity rhythm (RAR) is one of the most prominent outputs of the circadian system. However, little is known about the relationships between RAR and different domains of cognitive function in older adults. The purpose of this study was to examine the relationships between RAR and various fields of cognitive function in older Americans.

METHODS

This study included a total of 2090 older adults ≥ 60 years old from the National Health and Nutrition Examination Survey (NHANES) in 2011-2014. RAR parameters were derived from accelerometer recordings. Cognitive function was assessed using the word learning subtest developed by the Consortium to Establish a Registry for Alzheimer's disease (CERAD W-L), the Animal Fluency Test (AFT) and the Digital Symbol Substitution Test (DSST). Linear regression was used to determine the relationships between RAR parameters (IS, IV, RA, L5, M10) and cognitive function scores (CERAD W-L, AFT, DSST).

RESULTS

After adjusting for potential confounders, lower IS and M10 were associated with lower CERAD W-L scores (P=0.033 and P=0.002, respectively). Weaker RA and higher L5 were associated with lower AFT scores (P<0.001 and P=0.001, respectively). And lower IS, RA, and higher L5 were associated with lower DSST scores (P=0.019, P<0.001 and P<0.001, respectively). In addition, the results of sensitivity analysis were similar to those of our main analyses. The main correlation results between the RAR indicators and cognitive function were robust.

CONCLUSIONS

This study suggested that the weakened and/or disrupted RAR was associated with cognitive decline in different domains in Americans over the age of 60.

Sleep Immune Cross Talk and Insomnia

Sleep and immunity have bidirectional relationships. In this chapter, we review the links between sleep and immunity, focusing on immune changes occurring in the insomnia disorder. During physiological sleep, there is a decrease of pro-inflammatory cytokines (IL-1, IL-6 and TNF-α) and a decrease of anti-inflammatory cytokines (IL-4, IL-10). Examinations of ratios of pro-inflammatory and anti-inflammatory cytokines allow to identify rather a pro-inflammatory activity at the beginning of the night and confirm then anti-inflammatory during the second part of the night. Immune cells, as NK-cells, decrease in the blood, due to their migration to secondary lymphoid organs, but their activity increases. Inversely, a short sleep duration appears associated with increased inflammatory processes and increased risk of infection.Only few studies have investigated changes in immunity in patients with insomnia disorder. These studies suggest that insomnia disorder is related to deregulation of the immune system, with an increase in the level of pro-inflammatory cytokines and change in rate of secretion and a decrease in the level of lymphocyte. Insomnia treatments, particularly cognitive behavioral therapy (CBT-I), seems to have a restorative effect not only on sleep, but also on the associated inflammation. Melatonin also seems to reduce inflammation in patients suffering from insomnia disorder.More studies are necessary to better understand the pathophysiology of changes in immune system in patients suffering from insomnia disorders and their clinical implications.

Potential Role of Sleep Deficiency in Inducing Immune Dysfunction

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

GOODNIGHT, SLEEP TIGHT, DON'T LET THE MICROBES BITE: A REVIEW OF SLEEP AND ITS EFFECTS ON SEPSIS AND INFLAMMATION

ABSTRACT

Sleep is a restorative biological process that is crucial for health and homeostasis. However, patient sleep is frequently interrupted in the hospital environment, particularly within the intensive care unit. Suboptimal sleep may alter the immune response and make patients more vulnerable to infection and sepsis. In addition, hospitalized patients with sepsis experience altered sleep relative to patients without infectious disease, suggesting a bidirectional interplay. Preclinical studies have generated complementary findings, and together, these studies have expanded our mechanistic understanding. This review article summarizes clinical and preclinical studies describing how sleep affects inflammation and the host's susceptibility to infection. We also highlight potential strategies to reverse the detrimental effects of sleep interruption in the intensive care unit.

Blunted rest-activity rhythm is associated with increased white blood-cell-based inflammatory markers in adults: an analysis from NHANES 2011-2014

Circadian rhythm disruption is associated with immune system disturbance and has been observed in many health problems where chronic-inflammation acts as a major contributor. We aim to examine whether rest-activity circadian rhythm is associated with chronic inflammation using white blood-cell-based inflammatory indices including white blood cell (WBC) count, neutrophil count, neutrophil-to-lymphocyte ratio (NLR) and systemic immune-inflammation index (SII). We analyzed the data from 8089 adults (age≥20) with at least 4 days of validated accelerometer recordings and a valid WBC count from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. Non-parametric rest-activity circadian rhythm parameters were derived from the accelerometer recordings. In the models adjusting multiple covariates, a one-quantile increase in relative amplitude (i.e. more robust circadian rhythm) was associated with 1 × 10⁸ cells/L decrease in WBC number (95% CI: 5 × 10⁷ to 1.5 × 10⁸, P < .001), 7 × 10⁷ cells/L decrease in neutrophils (95% CI: 3 × 10⁷ to 1.1 × 10⁸, P = .003) and 15.2 × 10⁹ /L decrease in SII (95% CI: 6 × 10⁹ /L to 20 × 10⁹/L, P = .019). Consistent results were also observed for the association of M10 value and L5 value with these inflammatory indices. Our results indicated that blunted rest-activity circadian rhythm is associated with increased white blood-cell-based inflammatory indices in adults, suggesting interventions aiming at enhancing circadian rhythm by lifestyle programs may be a novel approach to improve the general health.

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

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

Insomnia with objective short sleep duration in women with temporomandibular joint disorder: quantitative sensory testing, inflammation and clinical pain profiles

OBJECTIVES/BACKGROUND

Temporomandibular joint disorder (TMD) is a disabling facial pain syndrome with a high prevalence of insomnia that primarily affects women. Insomnia with objective short sleep duration (ISSD) is an emerging phenotype linked to cardiometabolic morbidity and increased mortality. The present report examines the association of ISSD on clinical and laboratory pain and systemic inflammation in TMD.

METHODS

We collected baseline data from 128 women with TMD and insomnia as part of a clinical trial evaluating psychological interventions for sleep and pain. Participants completed self-report questionnaires, one-night polysomnography, a two-week actigraphy assessment, quantitative sensory testing (QST) to assess cold pain tolerance, pain sensitivity and central sensitization and circulating Interleukin-6 levels were measured to assess systemic inflammation.

RESULTS

24.2% (n = 31) of the sample met criteria for ISSD [polysomnography (sleep duration <6 h)]. Compared to those with insomnia and normal sleep duration, ISSD were older (40.4 vs. 34.9,p < 0.05) and a greater proportion self-identified as Black (48.4% vs 11.3%,p < 0.001). Multivariate regressions revealed that ISSD endorsed higher self-report pain severity and functional limitation of the jaw. ISSD also demonstrated increased generalized pain sensitivity, enhanced central sensitization, cold pressor tolerance and higher resting interleukin-6 levels.

CONCLUSIONS

This is the first study to characterize the ISSD phenotype in a chronic pain sample and expand the scope of its negative health outcomes to chronic pain. ISSD may be an important chronic pain phenotype associated with a more severe clinical and laboratory pain profile, and future studies should focus on implications for treatment response and disease trajectory.

CLINICAL TRIAL

ClinicalTrials.gov Identifier: NCT01794624.

Poor Sleep Quality is Linked to Elevated Extracellular Vesicle-Associated Inflammatory Cytokines in Warfighters With Chronic Mild Traumatic Brain Injuries

Background: Elevations of inflammatory cytokine levels occur immediately after mild traumatic brain injury (mTBI) and can persist for years. These elevations have been associated with neuropsychological outcomes, including depression and PTSD symptoms. Sleep disorders, another common sequelae of mTBI, are independently associated with inflammation in otherwise healthy individuals. However, whether sleep and inflammation are linked in chronic mTBI has not been reported.

Methods: A retrospective cross-sectional cohort of warfighters was used to investigate the hypothesis that inflammation may be linked to sleep quality in chronic mTBI. Clinical history, peripheral blood samples, and sleep quality scores were collected from 182 warfighters (n = 138 mTBI; n = 44 controls) during enrollment in the Chronic Effects of Neurotrauma Consortium study. Biomarkers of inflammation (IL-6, IL-10, TNFα cytokines) from plasma and plasma-derived extracellular vesicles (EVs) were quantified using single molecule array. Relationships between sleep quality and cytokine levels were assessed, controlling for age, sex, and BMI. Using clinical cutoff scores for sleep quality, mTBI patients were then divided into “good” and “poor” sleepers and cytokine levels compared between groups.

Results: In mTBI participants, sleep quality was significantly associated with EV levels of IL-10 [ß (SE) = 0.11 (0.04), p = 0.01] and TNFα [ß (SE) = 0.07 (0.03), p < 0.01]. When divided according to “good” versus “poor” sleepers, those reporting poor sleep had significantly elevated EV IL-10 compared to those reporting good sleep [ß (SE) = 0.12 (0.04), p < 0.01]. Plasma-derived associations were not significant. No associations were found between sleep quality and cytokine levels in controls.

Conclusion: These results suggest a significant relationship between sleep quality and chronic inflammation in mTBI patients. Clinically, mTBI patients with a high likelihood of sleep disorders demonstrate elevated levels of inflammatory cytokines. Signal from EVs, though smaller in magnitude, may have stronger clinical associations than from plasma. Sleep-focused interventions may also serve to regulate chronic inflammatory processes in these patients. Larger prospective studies are needed to investigate the mechanisms and therapeutic implications of the likely bi-directional relationship between sleep and inflammation following mTBI.

Poor Diet, Long Sleep, and Lack of Physical Activity Are Associated with Inflammation among Non-Demented Community-Dwelling Elderly

Inflammation in elderly is associated with physical and cognitive morbidity and mortality. We aimed to explore the association of modifiable lifestyle parameters with inflammation among non-demented, community-dwelling elderly. A sub-sample of 117 patients with mild cognitive impairment (MCI, n = 63) and cognitively non-impaired controls (CNI, n = 54) were recruited from a large, population-based cohort in Crete, Greece, of 3140 elders (>60 years old). All participants underwent assessment of medical history/physical examination, extensive neuropsychiatric/neuropsychological evaluation, diet, three-day 24-h actigraphy, subjective sleep, physical activity, and measurement of IL-6 and TNFα plasma levels. Associations between inflammatory markers and diet, objective sleep duration, subjective sleep quality, and lack of physical activity were assessed using multivariate models. Regression analyses in the total group revealed significant associations between TNF-α and low vegetable consumption (p = 0.003), and marginally with objective long nighttime sleep duration (p = 0.04). In addition, IL-6 was associated with low vegetable consumption (p = 0.001) and lack of physical activity (p = 0.001). Poor diet and lack of physical activity appear to be modifiable risk factors of inflammation, whereas long sleep appears to be a marker of increased inflammatory response in elderly. Our findings may have clinical implications given the association of inflammatory response with morbidity, including cognitive decline, and mortality in elderly.

Investigating obesity-related risk factors for childhood asthma

BACKGROUND

We tested the hypothesis that multiple obesity-related risk factors (obesity, physical activity, cardiopulmonary physical fitness, sleep-disorder breathing (SDB), and sleep quality) are associated with childhood asthma using a Mendelian randomization (MR) design. Furthermore, we aim to investigate whether these risk factors were associated with incident asthma prospectively.

METHODS

In total, 7069 children aged 12 from the Taiwan Children Health Study were enrolled in the current study. Cross-sectional logistic regression, one-sample MR, summary-level MR sensitivity analyses, and prospective survival analyses were used to investigate each causal pathway.

RESULTS

In MR analysis, three of the five risk factors (obesity, SDB, and sleep quality) were associated with asthma, with the highest effect sizes per inter-quartile range (IQR) increase observed for sleep quality (odds ratio [OR] = 1.42; 95% confidence interval [CI]: 1.06 to 1.92) and the lowest for obesity (OR = 1.08; 95% CI: 1.00-1.16). In the prospective survival analysis, obesity showed the highest risk of incident asthma per IQR increase (hazard ratio [HR] = 1.28; 95% CI: 1.05 to 1.56), followed by SDB (HR = 1.18; 95% CI: 1.08 to 1.29) and sleep quality (HR = 1.10; 95% CI: 1.03 to 1.17).

CONCLUSION

Among the examined factors, the most plausible risk factors for asthma were obesity, SDB, and poor sleep quality. For the prevention of childhood asthma, relevant stakeholders should prioritize improving children's sleep quality and preventing obesity comorbidities such as SDB.

Characterisation of insomnia as an environmental risk factor for asthma via Mendelian randomization and gene environment interaction

Asthma is a complex disease that is reportedly associated with insomnia. However, the causal directionality of this association is still unclear. We used asthma and insomnia-associated single nucleotide polymorphisms (SNPs) and genome-wide association study (GWAS) summary statistics to test the causal directionality between insomnia and asthma via Mendelian randomization (MR) analysis. We also performed a cross-trait meta-analysis using UK Biobank GWAS summary statistics and a gene–environment interaction study using data from UK Biobank. The interaction of genetic risk score for asthma (GRS_asthma) with insomnia on asthma was tested by logistic regression. Insomnia was a risk factor for the incidence of asthma, as revealed by three different methods of MR analysis. However, asthma did not act as a risk factor for insomnia. The cross-trait meta-analysis identified 28 genetic loci shared between asthma and insomnia. In the gene–environment interaction study, GRS_asthma interacted with insomnia to significantly affect the risk of asthma. The results of this study highlight the importance of insomnia as a risk factor of asthma, and warrant further analysis of the mechanism through which insomnia affects the risk of asthma.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The Epidemiology of Insomnia and Sleep Duration Across Mental and Physical Health: The SHoT Study

Objective

Numerous epidemiological studies have been conducted to examine the prevalence and comorbidities of insomnia and document sleep duration, but a common limitation in many studies is the lack of use of agreed-upon definitions of insomnia, as well as insufficient statistical power to examine comorbid mental and physical disorders/conditions.

Aim

To examine the prevalence of insomnia operationalized according to formal DSM-5 criteria and differences in mean sleep duration across a wide range of mental and physical disorders, examining men and women separately.

Materials and Methods

Data stem from the SHoT study (Students' Health and Wellbeing Study), a national survey of all college and university students in Norway. In all, 162,512 students aged 18-35 received an invitation to participate, of whom 50,054 students completed the internet-based survey (attendance rate: 30.8%). Insomnia was defined according to the Diagnostic and Statistical Manual of Mental Disorders (5th ed.) criteria and sleep duration was calculated separately for weekdays and weekends. Self-reported mental and physical disorders/conditions were assessed using a pre-defined list modified to fit this age group. Pearson chi-squared tests were used to examine the prevalence of insomnia across the various mental and physical disorders/conditions in men and women separately, and log-link binomial regression analysis were used to calculate effect-sizes, adjusting for age.

Results

The prevalence of insomnia in both sexes was significantly higher across all mental disorders compared with a healthy reference group. Among females, the prevalence of insomnia ranged from 61.3% for comorbid depression (adj. RR = 2.49, 95% CI: 2.40) to 83.3% for comorbid schizophrenia (adj. RR = 3.37, 95% CI: 2.61-4.35). For males, the insomnia prevalence ranged from 32.3% for comorbid autism/Asperger (adj. RR = 2.02, 95% CI: 1.39-2.92) to 74.2% for comorbid eating disorder (adj. RR = 4.51, 95% CI: 3.87-5.27). The overall prevalence of insomnia was also significantly higher across most physical conditions compared with the healthy reference group, although generally lower compared to the mental disorders. For females, the insomnia prevalence ranged from 25% for comorbid multiple sclerosis (not significant) to 65.4% for comorbid chronic fatigue syndrome/ME (adj. RR = 2.66, 95% CI: 2.44-2.89). For males, the insomnia prevalence ranged from 20% for both comorbid cancer and diabetes (not significant) to 74.2% for comorbid fibromyalgia (adj. RR = 4.35, 95% CI: 2.96-6.39). Similar patterns were observed for sleep duration, with a significantly shorter sleep duration for across many physical disorders, but especially mental disorders.

Conclusion

Insomnia and short sleep duration are strongly associated with a range of different disorders and conditions. Insomnia is most strongly associated with mental disorders, and physical conditions characterized by some level of psychological or psychosomatic properties.

Changed signals of blood adenosine and cytokines are associated with parameters of sleep and/or cognition in the patients with chronic insomnia disorder

OBJECTIVES

This study aimed to investigate whether plasma levels of adenosine, adenosine deaminase (ADA), and certain cytokines change in patients with chronic insomnia disorder (CID), and if so, whether these alterations are associated with poor sleep quality and cognitive dysfunction.

METHODS

Fifty-five CID patients were selected for the study, along with fifty-five healthy controls (HC) matched to the patients according to their basic data. All subjects completed sleep, emotion, and cognition assessments, with some CID patients also completing an overnight polysomnography. The plasma level of adenosine was measured using liquid chromatography-tandem mass spectrometry, while ADA level was quantified using a quantitative sandwich enzyme-linked immunosorbent assay. Levels of cytokines, including IL-1β, IL-2, IL-4, IL-6, IL-10, IL-12, TNF-α, and IFN-γ, were measured using Luminex liquid chip technology.

RESULTS

CID patients had a lower adenosine level, and higher levels of ADA and some of the cytokines (IL-1β, IL-2, IL-6, IL-10 and TNF-α) compared with controls. In the CID group, plasma concentrations of adenosine were negatively correlated with Pittsburgh Sleep Quality Index scores, while concentrations of IL-1β, IL-6 and TNF-α were positively correlated with these scores. Concentrations of IL-1β and TNF-α were negatively correlated with scores on the Chinese-Beijing Version of the Montreal Cognitive Assessment. Moreover, levels of IL-1β, TNF-α, IL-6, and IL-2 were positively correlated with memory test errors by CID patients after controlling for confounding factors.

CONCLUSIONS

The reduced adenosine and elevated cytokine levels of CID patients were associated with the severity of insomnia and/or cognitive dysfunction.

Maternal insomnia during the COVID-19 pandemic: associations with depression and anxiety

BACKGROUND

The COVID-19 outbreak has made people more prone to depression, anxiety and insomnia, and females are at a high risk of developing these conditions. As a special group, pregnant and lying-in women must pay close attention to their physical and mental health, as both have consequences for the mother and the fetus. However, knowledge regarding the status of depression, anxiety and insomnia among these women is limited.

AIM

This study aimed to examine insomnia and psychological factors among pregnant and lying-in women during the COVID-19 pandemic and provide theoretical support for intervention research.

METHODS

In total, 2235 pregnant and lying-in women from 12 provinces in China were surveyed; their average age was 30.25 years (SD = 3.99, range = 19-47 years).

PARTICIPANTS AND SETTING

The participants completed electronic questionnaires designed to collect demographic information and assess levels of depression, anxiety and insomnia.

RESULTS

The prevalence of insomnia in the sample was 18.9%. Depression and anxiety were significant predictors of insomnia. Participants in high-risk areas, those with a disease history, those with economic losses due to the outbreak, and those in the postpartum period had significantly higher insomnia scores.

DISCUSSION

The incidence of insomnia among pregnant and lying-in women is not serious in the context of the epidemic, which may be related to the sociocultural background and current epidemic situation in China.

CONCLUSION

Depression and anxiety are more indicative of insomnia than demographic variables.

Understanding the Role of Interleukin-6 (IL-6) in the Joint and Beyond: A Comprehensive Review of IL-6 Inhibition for the Management of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic, debilitating autoimmune disorder involving inflammation and progressive destruction of the joints, affecting up to 1% of the population. The majority of patients with RA have one or more comorbid conditions, the most common being cardiovascular disease, osteoporosis, and depression, the presence of which are associated with poorer clinical outcomes and lower health-related quality of life. RA pathogenesis is driven by a complex network of proinflammatory cells and cytokines, and of these, interleukin-6 (IL-6) plays a key role in the chronic inflammation associated with RA. Through cell signaling that can be initiated by both membrane-bound and soluble forms of its receptor, IL-6 acts both locally to promote joint inflammation and destruction, and in the circulation to mediate extra-articular manifestations of RA, including pain, fatigue, morning stiffness, anemia, and weight loss. This narrative review describes the role of IL-6 in the pathogenesis of RA, its comorbidities, and extra-articular systemic manifestations, and examines the effects of the IL-6 receptor inhibitors sarilumab and tocilizumab on clinical endpoints of RA, patient-reported outcomes, and common comorbidities and extra-articular manifestations.

Cognitive Behavioral Therapy for Insomnia: A Promising Treatment for Insomnia, Pain, and Depression in Patients With IBD

Over 75% of people with active inflammatory bowel diseases (IBDs) report sleep disturbances, which heighten risk for IBD relapse and flares. Despite mounting evidence for sleep disturbances in IBD, discussion of treatment is severely limited. The most common sleep disturbance, insomnia, occurs in over 50% of adults with chronic health conditions. Herein we describe the gold standard treatment for insomnia, Cognitive Behavioral Therapy for Insomnia (CBT-I). Although yet to be studied in IBD, CBT-I reduces a number of IBD-related comorbidities, including chronic pain, depression, and systemic inflammation. We describe treatment with CBT-I, the impact of CBT-I on these comorbidities, and recommendations for providers.

Relationships between objective sleep parameters and inflammatory biomarkers in pregnancy

We examined the relationships between sleep and inflammatory biomarkers during late pregnancy. Seventy-four women underwent an overnight sleep assessment by polysomnography. Blood samples were collected before bedtime and again within 1 h upon awakening to measure C-reactive protein (CRP), interleukin (IL)-6, and IL-6 soluble receptor. Sleep parameters included variables characterizing sleep architecture and sleep continuity. The participants were 32.2 (SD = 4.1) years old, and the average gestational age was 32.8 (3.5) weeks. Controlling for covariates, evening CRP was negatively associated with N3 sleep (β = -0.30, P = 0.010). N3 sleep was also negatively associated with morning CRP (β = -0.26, P = 0.036), with a higher percentage of N3 sleep associated with a lower level of morning CRP. Contrarily, there was a tendency for a positive association between stage N2 sleep and morning CRP (β = 0.23, P = 0.065). Stage N1 sleep was associated with morning IL-6 (β = 0.28, P = 0.021), with a higher percentage of N1 sleep associated with a higher morning IL-6. No significant associations were found between morning inflammatory biomarkers and sleep continuity parameters. In conclusion, increased light sleep was associated with increased inflammatory biomarkers, whereas more deep sleep was associated with decreased inflammatory biomarkers. These findings further support the interactions between sleep and the immune system during late pregnancy.

Chronic Insomnia Is Associated with Higher Circulating Interleukin-8 in Patients with Atherosclerotic Cerebral Small Vessel Disease

OBJECTIVE

Chronic inflammatory responses and leukocyte infiltration are classical pathological features of cerebral small vessel disease (CSVD). To date, limited evidence of a relationship between chronic insomnia and inflammatory responses in patients with CSVD has been uncovered. The purpose of the present study was to investigate the potential relationship between chronic insomnia and pro-inflammatory cytokine levels in patients with atherosclerotic CSVD (A-CSVD).

METHODS

In total, 76 A-CSVD patients with or without chronic insomnia (CI) confirmed using magnetic resonance (MR) were prospectively recruited. Overnight polysomnography (PSG) was performed and serum levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, IL-17A, IL-8, and IL-12 assessed. Cytokine levels were compared between CSVD+CI (study group) and CSVD without CI (control group) patients, and the correlations between PSG parameters and cytokine levels were explored in all patients via multiple linear regression analyses.

RESULTS

The serum IL-8 level of the study group (12.3±4.4 pg/mL) was significantly higher than that of the control group (7.5±2.2 pg/mL; P<0.05). PSG measurements showed that patients in the study group had significantly higher sleep onset latency (SOL), arousal index (ArI) and wake after sleep onset (WASO) as well as lower total sleep time (TST), sleep efficiency (SE) and stage 3 NREM sleep (N-3) ratio, compared with the control group (P<0.05). Multiple linear regression analyses led to the identification of ArI (β=0.026, P<0.05) and TST (β=-0.054, P<0.05) as significant positive and negative predictors of the IL-8 level, respectively.

CONCLUSION

Chronic insomnia, in particular, sleep fragmentation and short sleep duration, may be involved in promotion of serum IL-8 expression in patients with atherosclerotic CSVD.

Sleep and cardiovascular disease: Emerging opportunities for psychology

Sleep disturbances and disorders have been implicated in cardiovascular morbidity and mortality. Converging evidence suggests that psychosocial factors that confer risk or resilience to cardiovascular disease (CVD) are also related to sleep. Profound differences in sleep among racial/ethnic minorities compared with non-Hispanic Whites in the United States suggest that sleep, and its interplay with psychosocial factors, may contribute to observed disparities in CVD and in health and functioning more broadly. Less understood is the extent to which sleep and psychosocial factors interact to influence the pathophysiology and clinical course of CVD. This article reviews observational and experimental evidence linking short sleep duration and insomnia, both modifiable sleep disturbances, to CVD, including key physiological mechanisms. Also reviewed is evidence of significant interrelationships among sleep, race/ethnicity, and psychosocial factors known to confer risk or resilience to CVD, including depression, psychological stress, and close interpersonal relationships. It is proposed that a transdisciplinary research framework that integrates knowledge, methods, and measures from the fields of psychology and sleep research may be used to catalyze advances in the prevention and treatment of CVD. Also discussed are promising new directions, expected challenges, and the importance of training in transdisciplinary science and research approaches. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Clinical Pain-related Outcomes and Inflammatory Cytokine Response to Pain Following Insomnia Improvement in Adults With Knee Osteoarthritis

OBJECTIVES

Clinical insomnia is known to affect pain, but mechanisms are unclear. Insomnia can dysregulate inflammatory pathway, and inflammation plays a mediating role in pain. It is unclear whether insomnia-related alterations in inflammation can be modified with insomnia improvement, and if such alterations parallel improvement in pain. The current study objective was to provide proof of concept for the role of insomnia in inflammation and pain by testing whether improving insomnia would reduce pain and related physical function, and, concurrently, modulate inflammatory responses.

MATERIALS AND METHODS

Thirty adults with osteoarthritis knee pain and insomnia (Insomnia Severity Index >10) provided baseline measures of osteoarthritis and laboratory pain, and serial blood samples for inflammatory biomarkers, interleukin 6, and tumor necrosis factor α, before and after pain testing. To manipulate insomnia, participants were randomly assigned to a 6-week cognitive-behavioral therapy for insomnia (n=16); or wait-list control (n=14). At 8-weeks (time 2), all measures were repeated. To directly test insomnia improvement effects, participants were grouped by insomnia status at time 2 after confirming baseline equivalency on all outcomes.

RESULTS

Compared with those maintaining insomnia at time 2 (Insomnia Severity Index ≥8; n=18), those whose insomnia improved at time 2 (n=12) had significantly improved physical functioning, decline in knee pain during transfer activities, and attenuated increase in interleukin 6 and less decrease in tumor necrosis factor α across the pain testing session.

DISCUSSION

These findings suggest further exploration of inflammatory pathways linking clinical insomnia, and its improvement, to chronic pain.

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.

Insomnia and risk of mortality from all-cause, cardiovascular disease, and cancer: Systematic review and meta-analysis of prospective cohort studies

Growing evidence indicates that insomnia may be associated with mortality. However, these findings have been inconsistent. We systematically searched MEDLINE and EMBASE to identify prospective cohort studies that assessed the association between insomnia disorder/individual insomnia symptoms and the risk of mortality among adults aged ≥18 yrs. We addressed this association using summary hazard ratios (HRs) and 95% confidence intervals (CIs) calculated using random-effects meta-analysis, and the GRADE approach to rate the certainty of evidence. Twenty-nine cohorts including 1,598,628 individuals (55.3% men; mean age 63.7 yrs old) with a median follow-up duration of 10.5 yrs proved eligible. Difficulty falling asleep (DFA) and non-restorative sleep (NRS) were associated with an increased risk of all-cause mortality (DFA: HR = 1.13, 95%CI 1.03 to 1.23, p = 0.009, moderate certainty; NRS: HR = 1.23, 95%CI 1.07 to 1.42, p = 0.003, high certainty) and cardiovascular disease mortality (DFA: 1.20, 95%CI: 1.01, 1.43; p = 0.04, moderate certainty; NRS: HR = 1.48, 95%CI 1.06 to 2.06, p = 0.02, moderate certainty). Convincing associations between DFA and all-cause mortality were restricted to the mid to older-aged population (moderate credibility). Insomnia disorder, difficulty maintaining sleep, and early morning awakening proved to be unassociated with all-cause and cardiovascular disease mortality. No insomnia symptoms proved to be associated with cancer-related mortality.

The Sleep-Immune Crosstalk in Health and Disease

Sleep and immunity are bidirectionally linked. Immune system activation alters sleep, and sleep in turn affects the innate and adaptive arm of our body's defense system. Stimulation of the immune system by microbial challenges triggers an inflammatory response, which, depending on its magnitude and time course, can induce an increase in sleep duration and intensity, but also a disruption of sleep. Enhancement of sleep during an infection is assumed to feedback to the immune system to promote host defense. Indeed, sleep affects various immune parameters, is associated with a reduced infection risk, and can improve infection outcome and vaccination responses. The induction of a hormonal constellation that supports immune functions is one likely mechanism underlying the immune-supporting effects of sleep. In the absence of an infectious challenge, sleep appears to promote inflammatory homeostasis through effects on several inflammatory mediators, such as cytokines. This notion is supported by findings that prolonged sleep deficiency (e.g., short sleep duration, sleep disturbance) can lead to chronic, systemic low-grade inflammation and is associated with various diseases that have an inflammatory component, like diabetes, atherosclerosis, and neurodegeneration. Here, we review available data on this regulatory sleep-immune crosstalk, point out methodological challenges, and suggest questions open for future research.

Relations of combat stress and posttraumatic stress disorder to 24-h plasma and cerebrospinal fluid interleukin-6 levels and circadian rhythmicity

BACKGROUND

Acute and chronic stress can lead to a dysregulation of the immune response. Growing evidence suggests peripheral immune dysregulation and low-grade systemic inflammation in posttraumatic stress disorder (PTSD), with numerous reports of elevated plasma interleukin-6 (IL-6) levels. However, only a few studies have assessed IL-6 levels in the cerebrospinal fluid (CSF). Most of those have used single time-point measurements, and thus cannot take circadian level variability and CSF-plasma IL-6 correlations into account.

METHODS

This study used time-matched, sequential 24-h plasma and CSF measurements to investigate the effects of combat stress and PTSD on physiologic levels and biorhythmicity of IL-6 in 35 male study volunteers, divided in 3 groups: (PTSD = 12, combat controls, CC = 12, and non-deployed healthy controls, HC = 11).

RESULTS

Our findings show no differences in diurnal mean concentrations of plasma and CSF IL-6 across the three comparison groups. However, a significantly blunted circadian rhythm of plasma IL-6 across 24 h was observed in all combat-zone deployed participants, with or without PTSD, in comparison to HC. CSF IL-6 rhythmicity was unaffected by combat deployment or PTSD.

CONCLUSIONS

Although no significant group differences in mean IL-6 concentration in either CSF or plasma over a 24-h timeframe was observed, we provide first evidence for a disrupted peripheral IL-6 circadian rhythm as a sequel of combat deployment, with this disruption occurring in both PTSD and CC groups. The plasma IL-6 circadian blunting remains to be replicated and its cause elucidated in future research.

A critical review on grape polyphenols for neuroprotection: Strategies to enhance bioefficacy

The aging of populations worldwide is driving greater demands for dietary polyphenols which have been recognized as promising prophylactic and/or therapeutic agents in the context of neurodegeneration, and are ubiquitously present in plant-based diets. In particular, grape-derived products encompass a wide array of phenolic compounds purported with multiple health benefits including neuroprotective efficacy. Despite the increasing preclinical and clinical evidence demonstrating high potential of grape polyphenol (GPP)-rich botanicals in preventing and attenuating diverse neurodegenerative disorders, the limited bioavailability of GPPs, especially in the brain, generates questions as to their applications and effectiveness in neuroprotection. To address this issue, significant research efforts have been made to enhance oral bioavailability of GPPs via application of novel strategies. This review highlights some critical issues related to the bioavailability and neuroprotective efficacy of GPPs and GPP-rich botanicals. The representative bioavailability-enhancing strategies are critically reviewed to provide practical solutions for augmenting the bioefficacy of GPP-rich botanicals. Synergistic applications of encapsulation techniques (for physiochemical protection and bypassing xenobiotic metabolism) and dietary intervention strategies involving modulation of gut microbiota (for generating more bioavailable phenolic metabolites) appear promising, and may substantially enhance the bioefficacy, especially the neuroprotective efficacy, of orally consumed GPPs.

Glucocorticoid and inflammatory reactivity to a repeated physiological stressor in insomnia disorder

Despite known associations of insomnia disorder with alterations in cytokine and glucocorticoid (GC) production, neither the sensitivity of immune cells to a GC signal nor the reactivity of the hypothalamus-pituitary-adrenal (HPA) axis and inflammatory system to stress, or adaptation of these systems to repeated stress have been assessed in patients with insomnia. To investigate potential dysregulation in stress reactivity and adaptation to repeated exposure, a physiological stressor (the cold pressor test; CPT) was repeatedly administered to N = 20 participants with insomnia disorder (based on DSM-V, 18 females, age 30 ± 2.5 years) and N = 20 sex-matched healthy controls following an at-home actigraphy and in-laboratory PSG. HPA and inflammatory markers (serum cortisol, plasma interleukin [IL]-6) were measured at baseline/resting levels and following each of the three CPTs. In addition, sensitivity of monocytes to the synthetic GC dexamethasone was assessed in-vitro at baseline levels in order to examine the cortisol-IL-6 interplay at the cell level. Compared to healthy controls, individuals with insomnia disorder exhibited shorter sleep duration as assessed by actigraphy and PSG (p ≤ 0.05). HPA, but not inflammatory reactivity to the repeated CPT challenge was greater in insomnia disorder (p ≤ 0.05 for group effect), due to greater cortisol responses to the initial CPT (p ≤ 0.05). There were no between-group differences in the ability of the HPA to adapt to stress repetition nor in basal/resting levels of cortisol, IL-6, and GC sensitivity. These findings suggest that insomnia disorder potentiates HPA axis reactivity to initial/novel stressors, which may constitute a pathway underlying adverse health consequences in the long term.

Insomnia and hypertension: A systematic review

Insomnia is a prevalent sleep disorder that is associated with a multitude of health consequences. Particularly, insomnia has been associated with cardiovascular disease and its precursors, such as hypertension and blood pressure (BP) non-dipping. The present systematic review aimed to summarize the evidence on the concurrent and prospective associations between insomnia and hypertension and/or BP. Using electronic search engines (PubMed, SCOPUS, PsycINFO), 5,618 articles published from January 1970 to December 2017 were identified, and 64 met the inclusion criteria (26 to 162,121 participants; age range: 18-100; 46.4% male). Insomnia was based on diagnostic or non-diagnostic criteria. Hypertension was based on self-or physician-reports, antihypertensive medication use, and/or measured BP. Findings indicate that when insomnia is frequent, chronic, and/or accompanied with short sleep duration or objective markers of arousal, there is a strong association with hypertension/BP. Based on limited studies, hypertension did not significantly predict future insomnia in middle-aged adults, but did in older adults. Based on a majority of case-control studies, no differences in BP were found between participants with and without insomnia. Further research is needed to identify putative pathophysiological mechanisms underlying the link between insomnia and hypertension. The impact of insomnia therapy on BP should also be further examined in the future.

Increased Risk of Myofascial Pain Syndrome Among Patients with Insomnia

Objective

The aim of this study is to evaluate the risk of developing myofascial pain syndrome among patients diagnosed with insomnia.

Methods

We conducted a population-based longitudinal study of a matched cohort with 7,895 participants (1,579 patients with insomnia and 6,316 controls) who were selected from the Taiwan National Health Insurance Research Database. The patients were observed for a maximum of 10 years to determine the incidence of newly diagnosed myofascial pain syndrome. A Cox regression analysis was performed to identify the risk factors associated with myofascial pain syndrome in patients with insomnia.

Results

During the 10-year follow-up period, 182 insomnia patients (14.9 per 1,000 person-years) and 379 controls (7.5 per 1,000 person-years) were diagnosed with myofascial pain syndrome. The incidence risk ratio of myofascial pain syndrome between the insomnia and control patients was 2.00 (95% confidence interval [CI] = 1.67-2.38, P  < 0.001). After adjusting for age, sex, monthly income, urbanization, and comorbidities, the insomnia patients were 1.93 times more likely to develop myofascial pain syndrome (95% CI = 1.62-2.31, P  < .001) than the control patients. Malignant neoplasm (hazard ratio = 3.08) and living in urban areas (hazard ratio = 3.05) were identified as independent risk factors for myofascial pain syndrome in patients with insomnia.

Conclusions

Patients with insomnia had a higher risk of developing myofascial pain syndrome than controls. This study adds to the understanding of the complex relationship between sleep disturbance and pain.

Insomnia Symptoms Are Associated With Abnormal Endothelial Function

BACKGROUND

Insomnia is a prevalent sleep disorder, and it has been increasingly associated with cardiovascular morbidity and mortality. The reasons for this relationship are not completely understood but may involve endothelial dysfunction. In this study, we hypothesized that insomnia symptoms would be associated with reduced endothelial function.

METHODS

Working adults (n = 496, 67.5% female, 78.6% white, mean age 48.7 [SD, 10.8] years, body mass index 28.2 [SD, 6.7] kg/m, diabetes 5.8%, hypertension 20.0%, hyperlipidemia 17.9%, heart disease 2.6%) enrolled in the Emory-Georgia Tech Predictive Health Institute study completed baseline demographic, clinical, depression (Beck Depression Inventory II), anxiety (General Anxiety Disorder 7), sleep (Pittsburg Sleep Quality Index), and noninvasive endothelial function (brachial artery flow-mediated dilation [FMD]) measures. Insomnia symptoms were defined as subjective sleep latency of 30 minutes or longer, nighttime or early morning awakenings, and/or sleep medication use occurring 3 times or more per week in the past month.

RESULTS

Insomnia symptoms were reported by 39.5% of participants. Multivariable regression models showed that insomnia symptoms, age, baseline artery diameter, and dyslipidemia were inversely related to FMD. After adjusting for age, baseline artery diameter, and dyslipidemia, participants reporting insomnia symptoms had lower FMD than did participants reporting better sleep (adjusted FMD mean, 6.13% [SD, 0.28%] vs 6.83% [SD, 0.26%], P = .035).

CONCLUSION

In this study, insomnia symptoms were associated with reduced FMD. Research examining the therapeutic benefits of treating insomnia on endothelial function and future cardiovascular risk is warranted.

Altered nocturnal blood pressure profiles in women with insomnia disorder in the menopausal transition

OBJECTIVE

Insomnia disorder is a risk factor for cardiovascular (CV) pathology. It is unknown whether insomnia that develops in the context of the menopausal transition (MT) impacts the CV system. We assessed nocturnal blood pressure (BP) and heart rate (HR) profiles in women with insomnia disorder in the MT.

METHODS

Twelve women meeting DSM-IV criteria for insomnia in the MT (age, mean ± SD: 50.5 ± 3.6 y) and 11 controls (age, mean ± SD: 49.0 ± 3.0 y) had polysomnographic recordings on one or two nights during which beat-to-beat BP and HR were assessed and analyzed hourly from lights-out across the first 6 hours of the night and according to sleep stage. Physiological hot flashes were identified from fluctuations in sternal skin conductance.

RESULTS

Women with insomnia and controls had similar distributions of sleep stages and awakenings/arousals across hours of the night, although insomnia participants tended to have more wakefulness overall. More women in the insomnia group (7 of 12) than in the control group (2 of 11) had at least one physiological hot flash at night (P < 0.05). Both groups showed a drop in BP in the first part of the night; however, systolic and diastolic BP patterns diverged later, remaining low in controls but increasing in insomnia participants 4 to 6 hours after lights-out (P < 0.05). Both groups showed a similar pattern of decline in HR across the night.

CONCLUSIONS

Our findings suggest altered regulatory control of BP during sleep in the MT insomnia. The causes and long-term consequences of this altered nocturnal BP profile remain to be determined.

Proinflammatory Cytokines, Mood, and Sleep in Interepisode Bipolar Disorder and Insomnia: A Pilot Study With Implications for Psychosocial Interventions

OBJECTIVE

Proinflammatory cytokines are associated with bipolar disorder (BD), but less is known about how cytokines function during the interepisode period. This study examined cytokines, mood symptoms, and sleep in individuals with interepisode BD with complaints of insomnia. We also investigated the effects of a BD-specific modification of cognitive behavior therapy for insomnia (CBTI-BP) on cytokine levels.

METHODS

Twenty-two adults with interepisode BD type I and insomnia were drawn from a subset of a National Institute of Mental Health funded study. Participants were randomly allocated to CBTI-BP (n = 11) or psychoeducation (n = 11). Participants completed a sleep diary, rated self-report measures of mania and depression, and provided samples assayed for interleukin (IL)-6 and tumor necrosis factor soluble receptor 2 (sTNF-R2).

RESULTS

IL-6 was associated with mania symptoms (rs = 0.44, p = .041) and total sleep time (rs = -0.49, p = .026). IL-6 was related to depression symptoms at the trend level (rs = 0.43, p = .052). sTNF-R2 was not significantly related to mood or sleep measures. From pretreatment to posttreatment, CBTI-BP compared with psychoeducation was associated with a nonsignificant, large effect size decrease in IL-6 (z = -1.61, p = .13, d = -0.78) and a nonsignificant, small-medium effect size decrease in sTNF-R2 (z = -0.79, p = .44, d = -0.38).

CONCLUSIONS

These findings provide preliminary evidence that IL-6 is related to mania symptoms and shorter total sleep time in interepisode BD. A treatment that targets sleep in BD could potentially decrease IL-6 although replication is warranted.

Antisuicidal Response Following Ketamine Infusion Is Associated With Decreased Nighttime Wakefulness in Major Depressive Disorder and Bipolar Disorder

OBJECTIVE

Insomnia and disrupted sleep are associated with increased risk of suicide. The N-methyl-d-aspartate antagonist ketamine has been associated with reduced suicidal thoughts, but the mechanism of action is unknown. This study sought to evaluate differences in nocturnal wakefulness in depressed individuals who did and did not have an antisuicidal response to ketamine.

METHODS

Thirty-four participants with baseline suicidal ideation diagnosed with either DSM-IV major depressive disorder (n = 23) or bipolar depression (n = 11) between 2006 and 2013 completed nighttime electroencephalography (EEG) the night before and the night after a single ketamine infusion (0.5 mg/kg over 40 minutes). Suicidal ideation was assessed at baseline and the morning after ketamine infusion via several measures, including the Hamilton Depression Rating Scale suicide item, the suicide item of the Montgomery-Asberg Depression Rating Scale, and the first 5 items of the Scale for Suicide Ideation. A generalized linear mixed model evaluated differences in nocturnal wakefulness, as verified by EEG, between those who had an antisuicidal response to ketamine and those who did not, controlling for baseline nocturnal wakefulness. Results were also compared to the sleep of healthy controls (n = 22).

RESULTS

After analyses adjusted for baseline sleep, participants with an antisuicidal response to ketamine showed significantly reduced nocturnal wakefulness the night after ketamine infusion compared to those without an antisuicidal response (F₁,₂₂ = 5.04, P = .04). Level of nocturnal wakefulness after antisuicidal response to ketamine did not differ significantly from nocturnal wakefulness in the control sample but did differ at a trend level (F₁,₄₀ = 3.15, P = .08).

CONCLUSIONS

Reductions in wakefulness following ketamine may point to a biological mechanism underlying the effect of ketamine on suicidal ideation.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00088699.

Is insomnia a risk factor for new-onset asthma? A population-based study in Taiwan

OBJECTIVES

To determine whether insomnia at baseline is a risk factor for new-onset asthma.

METHODS

We recruited 48 871 patients with insomnia (insomnia group) newly diagnosed between 2002 and 2007, and 97 742 matched controls without insomnia (control group) from Taiwan's Longitudinal Health Insurance Database 2000. All of the patients were followed up for 4 years to see whether new-onset asthma developed. Patients with previous asthma or insomnia were excluded. The Poisson regression was used to estimate the incidence rate ratios (IRRs) and 95% CIs of asthma. Cox proportional hazard regression was used to calculate the risk of asthma between the two groups.

RESULTS

After a 4-year follow-up, 424 patients in the insomnia group and 409 in the control group developed asthma. The incidence rate of asthma was significantly higher in the insomnia group (22.01vs10.57 per 10 000 person-years). Patients with insomnia have a higher risk of developing new-onset asthma during the 4-year follow-up (HR: 2.08, 95% CI 1.82 to 2.39). The difference remained significant after adjustment (adjusted HR: 1.89, 95% CI 1.64 to 2.17).

CONCLUSIONS

This large population-based study suggests that insomnia at baseline is a risk factor for developing asthma.

Insomnia as a Precipitating Factor in New Onset Mental Illness: a Systematic Review of Recent Findings

PURPOSE

We aimed to systematically review recent publications (01/2014-03/2017) with longitudinal designs allowing for the assessment of the prospective risk of insomnia on new onset mental illness in key conditions: anxiety, depression, bipolar disorder, posttraumatic stress disorder, substance use disorders, and suicide.

RECENT FINDINGS

A literature yielded 1859 unique articles meeting search criteria were identified; 16 articles met all selection criteria and reviewed with some studies reporting on more than one mental health outcome. Overall, the review supports the hypothesis that insomnia is a predictor of subsequent mental illness. The evidence is strongest for an insomnia-depression relationship. The new studies identified and reviewed add to a modest number of publications supporting a prospective role of insomnia in new onset mental illness in three areas: anxiety disorders, bipolar disorder, and suicide. The few selected new studies focused on SUD were mixed, and no studies focused on PTSD were identified that met the selection criteria. Treatment of insomnia may also be a preventive mental health strategy.

Is Insomnia a Risk Factor for Decreased Influenza Vaccine Response?

Healthy young adult college students (N = 133) with Insomnia (n = 65) or No Insomnia (n = 68) were compared on influenza serum antibody levels pre- and four weeks postvaccination. Volunteers underwent structured clinical interviews for sleep disorders to ensure insomnia diagnoses, as well as psychiatric interviews, physical examinations, and drug testing to ensure comorbid health problems were not potential confounds. There were significant time (both groups had increases in antibody levels pre- to postvaccination) and group (Insomnia group had lower HI antibody levels overall) main effects, but the time × group interaction was nonsignificant. Exploratory analyses did find significant PSQI x Time (p < .001) and Insomnia Status × Time (p = .002) interaction effects. Results indicate insomnia may be a risk factor for lowered immunity to the influenza virus.

Hypertension with unsatisfactory sleep health (HUSH): study protocol for a randomized controlled trial

BACKGROUND

Insomnia is common in primary care medical practices. Although behavioral treatments for insomnia are safe, efficacious, and recommended in practice guidelines, they are not widely-available, and their effects on comorbid medical conditions remain uncertain. We are conducting a pragmatic clinical trial to test the efficacy of two cognitive behavioral treatments for insomnia (Brief Behavioral Treatment for Insomnia (BBTI) and Sleep Healthy Using the Internet (SHUTi)) versus an enhanced usual care condition (EUC).

METHODS/DESIGN

The study is a three-arm, parallel group, randomized controlled trial. Participants include 625 adults with hypertension and insomnia, recruited via electronic health records from primary care practices affiliated with a large academic medical center. After screening and baseline assessments, participants are randomized to treatment. BBTI is delivered individually with a live therapist via web-interface/telehealth sessions, while SHUTi is a self-guided, automated, interactive, web-based form of cognitive behavioral therapy for insomnia. Participants in EUC receive an individualized sleep report, educational resources, and an online educational video. Treatment outcomes are measured at 9 weeks, 6 months, and 12 months. The primary outcome is patient-reported sleep disturbances. Secondary outcomes include other self-reported sleep measures, home blood pressure, body mass index, quality of life, health functioning, healthcare utilization, and side effects.

DISCUSSION

This randomized clinical trial compares two efficacious insomnia interventions to EUC, and provides a cost-effective and efficient examination of their similarities and differences. The pragmatic orientation of this trial may impact sleep treatment delivery in real world clinical settings and advance the dissemination and implementation of behavioral sleep interventions.

TRIAL REGISTRATION

ClinicalTrials.gov (Identifier: NCT02508129 ; Date Registered: July 21, 2015).