Sleep and Psychoneuroimmunology

Total Sleep Time and BMI z-score Are Associated With Physical Function Mobility, Peer Relationship, and Pain Interference in Children Undergoing Routine Polysomnography: A PROMIS Approach

INTRODUCTION

Sleep disturbance, especially obstructive sleep apnea (OSA) and inadequate sleep, adversely affect various health-related quality of life (HR-QoL) domains in adults. Few studies have addressed problems with HR-QoL in children with OSA or sleep-related symptoms.

METHODS

Patients between ages 5 to 17 years who were referred to the sleep laboratory from June 2017 to August 2017 for overnight polysomnography were approached to participate in the study.

RESULTS

A total of 86 patients were included in the final analysis; 45 patients (52.3%) were male; and the median (interquartile range) of their mean BMI z-scores was 1.7 (0.5, 2.4). The patients were categorized by OSA severity as follows: 27 (31.4%) mild OSA, 11 (12.8%) moderate OSA, 24 (27.9%) severe OSA, and 24 (27.9%) without OSA. Severity of OSA was not correlated with any PROMIS domain. In univariable analyses, BMI z-score was negatively correlated with physical function mobility score (P = .002) and positively correlated with pain interference (P = .02) and pain intensity (P = .02). Total sleep time was positively correlated with physical function mobility (P = .03) and peer relationship (P = .002). Significant correlations between several PROMIS domains were also observed.

CONCLUSIONS

Total sleep time was associated with physical function mobility and peer relationship. Regression analysis demonstrated a relationship between BMI z-score, physical function mobility, and pain intensity in our study population.

COMMENTARY

A commentary on this article appears in this issue on page 541.

Behavioral, neuroendocrine and physiological indicators of the circadian biology of male and female rabbits

Adult rabbits show robust circadian rhythms of: nursing, food and water intake, hard faeces excretion, locomotion, body temperature, blood and intraocular pressure, corticosteroid secretion, and sleep. Control of several circadian rhythms involves a light-entrained circadian clock and a food-entrained oscillator. Nursing periodicity, however, relies on a suckling stimulation threshold. Brain structures regulating this activity include the paraventricular nucleus and preoptic area, as determined by lesions and quantification of cFOS- and PER1 clock gene-immunoreactive proteins. Melatonin synthesis in the rabbit pineal gland shows a diurnal rhythm, with highest values at night and lowest ones during the day. In kits the main zeitgeber is milk intake, which synchronizes locomotor activity, body temperature, and corticosterone secretion. Brain regions involved in these effects include the median preoptic nucleus and several olfactory structures. As models for particular human illnesses rabbits have been valuable for studying glaucoma and cardiovascular disease. Circadian variations in intraocular pressure (main risk factor for glaucoma) have been found, with highest values at night, which depend on sympathetic innervation. Rabbits fed a high fat diet develop cholesterol plaques and high blood pressure, as do humans, and such increased fat intake directly modulates cardiovascular homeostasis and circadian patterns, independently of white adipose tissue accumulation. Rabbits have also been useful to investigate the characteristics of sleep across the day and its modulation by infections, cytokines and other endogenous humoral factors. Rabbit circadian biology warrants deeper investigation of the role of the suprachiasmatic nucleus in regulating most behavioral and physiological rhythms described above.

Subjective Positive and Negative Sleep Variables Differentially Affect Cellular Immune Activity in a Breast Cancer Survivor: A Time-series Analysis Approach

This study on a breast cancer survivor suffering from cancer-related fatigue (CaRF) and depression investigated the bidirectional relationship between cellular immune activity and subjective sleep. The 49-year-old patient (breast cancer diagnosis 5 years before the study, currently in remission) collected her full urine output for 28 days in 12-h intervals (8:00 p.m. to 8:00 a.m. and 8:00 a.m. to 8:00 p.m.). These urine samples were used to determine urinary neopterin (cellular immune activation marker) and creatinine concentrations via high-pressure liquid chromatography (HPLC). Each morning, the patient answered questions on five sleep variables: sleep quality (SQ), sleep recreational value (SRV), total sleep time (TST), total wake time (TWT), and awakenings during sleep period (ADS). For the purpose of this study, the time series of the nighttime urinary neopterin levels and the five sleep variables were determined. Using centered moving average (CMA) smoothing and cross-correlational analysis, this study showed that increases in the positive sleep variables SQ and SRV were followed by urinary neopterin concentration decreases after 96–120 h (SQ, lag 4: r = −0.411; p = 0.044; SRV: lag 4: r = −0.472; p = 0.021) and 120–144 h (SRV, lag 5: r = −0.464; p = 0.026). Increases in the negative sleep variable TWT, by contrast, were followed by increases in urinary neopterin concentrations 72–96 h later (lag 3: r = 0.522; p = 0.009). No systematic effects in the other direction, i.e., from urinary neopterin levels to sleep, were observed in this study. Although preliminary, the findings of this study highlight the benefit of carefully investigating temporal delays and directions of effects when studying the dynamic relationship between sleep and immune variables in the natural context of everyday life.

Identification of Sleep-Modulated Pathways Involved in Neuroprotection from Stroke

STUDY OBJECTIVES

Sleep deprivation (SDp) performed before stroke induces an ischemic tolerance state as observed in other forms of preconditioning. As the mechanisms underlying this effect are not well understood, we used DNA oligonucleotide microarray analysis to identify the genes and the gene-pathways underlying SDp preconditioning effects.

DESIGN

Gene expression was analyzed 3 days after stroke in 4 experimental groups: (i) SDp performed before focal cerebral ischemia (IS) induction; (ii) SDp performed before sham surgery; (iii) IS without SDp; and (iv) sham surgery without SDp. SDp was performed by gentle handling during the last 6 h of the light period, and ischemia was induced immediately after.

SETTINGS

Basic sleep research laboratory.

MEASUREMENTS AND RESULTS

Stroke induced a massive alteration in gene expression both in sleep deprived and non-sleep deprived animals. However, compared to animals that underwent ischemia alone, SDp induced a general reduction in transcriptional changes with a reduction in the upregulation of genes involved in cell cycle regulation and immune response. Moreover, an upregulation of a new neuroendocrine pathway which included melanin concentrating hormone, glycoprotein hormones-α-polypeptide and hypocretin was observed exclusively in rats sleep deprived before stroke.

CONCLUSION

Our data indicate that sleep deprivation before stroke reprogrammed the signaling response to injury. The inhibition of cell cycle regulation and inflammation are neuroprotective mechanisms reported also for other forms of preconditioning treatment, whereas the implication of the neuroendocrine function is novel and has never been described before. These results therefore provide new insights into neuroprotective mechanisms involved in ischemic tolerance mechanisms.

Let’s save our nurses and doctors!

Introduction: Several studies have shown that healthcare service is a dangerous workplace, but the reasons have been remained unexplained. Aim: The aim of the authors was to obtain data on the health condition of health care professionals and identify the underlying risk factors for the increased morbidity. Method: Health care data obtained from 276 bedside nurses in 2004 and 1250 hospital employees in 2009 were analysed. In addition, the fate of department directors of Szent György University Hospital in Székesfehérvár between 1979 and 2010 was recorded and the data were compared to those obtained from a smaller hospital in Budapest during the same time period. Results: The body mass index of bedside nurses between the age of 30–35 years reached the upper limit of normal (which occurred 5–10 years earlier as compared to the average population) and then it increased continuously above the average value. In hospital employees the increase of body mass index was accompanied by an increase in the frequency of chronic diseases such as hypertension, allergy, thyroid dysfunction, rheumatologic diseases, diabetes, peptic ulcer, cancer and depression. When the cause of death of the department directors who died between 1979 and 2010 was analyzed the authors found that cancer death occurred in 77% and 82% of department directors in Székesfehérvár and Budapest hospitals, respectively, while cancer death rate in 2011 was 25.4% in Hungary. Conclusions: The authors propose that continuous psychological stress, night shifts, nonstop standby and surcharge may all suppress the activity of the immune system. This proposal seems to be supported by novel psycho-neuro-immunological research data. The solution could be early prevention using stress control. Orv. Hetil., 2014, 155(52), 2082–2092.

Sleep disorders and systemic lupus erythematosus

Objective

Sleep disturbances are often seen in rheumatic diseases, including systemic lupus erythematosus (SLE). However, the prevalence of sleep disorders in SLE as well as the contributing factors to their occurrence remain poorly understood. The aim of this paper is to review the clinical and psychobiological data on the relationship between sleep disturbances and SLE.

Method

We performed a systematic search of MEDLINE, EMBASE and PsychINFO, using MeSH headings and keywords for “sleep disorders” and “SLE.”

Results

Nine studies reporting the relationship between sleep disorders and SLE were found. Prevalence rates of sleep disorders ranged between 55% and 85%; differences in assessment techniques appeared to be a major source of this variability. In the majority of the studies an association between sleep disorders and disease activity, pain and fatigue has been reported. Psychosocial variables, depression, steroid use, and the role that sleep disruption has on pain, inflammation and cytokines, have been hypothesized as possible psychobiological factors.

Conclusions

Sleep disorders appear to occur in more than half of patients with SLE and appear to be associated with disease activity. Pain and fatigue are also related to sleep disorders. Among the hypotheses on the possible mechanisms underlining the association between sleep disorders and SLE, psychosocial/psychological factors, especially depression, were the most frequently reported.

Sleep problems and functional disability in children with functional gastrointestinal disorders: an examination of the potential mediating effects of physical and emotional symptoms

Background

Sleep disturbances are increasingly recognized as a common problem for children and adolescents with chronic pain conditions, but little is known about the prevalence, type, and impact of sleep problems in pediatric functional gastrointestinal disorders (FGIDs). The objectives of the current study were two-fold: 1) to describe the pattern of sleep disturbances reported in a large sample of children and adolescents with FGIDs; and, 2) to explore the impact of sleep by examining the inter-relationships between sleep disturbance, physical symptoms, emotional problems, and functional disability in this population.

Methods

Over a 3-year period, 283 children aged 8–17 years who were diagnosed with an FGID and a primary caretaker independently completed questionnaires regarding sleep, emotional functioning, physical symptoms, and functional disability during an initial evaluation for chronic abdominal pain at a pediatric tertiary care center. A verbal review of systems also was collected at that time. Descriptive statistics were used to characterize the pattern of sleep disturbances reported, while structural equation modeling (SEM) was employed to test theorized meditational relationships between sleep and functional disability through physical and emotional symptoms.

Results

Clinically significant elevations in sleep problems were found in 45% of the sample, with difficulties related to sleep onset and maintenance being most common. No difference was seen by specific FGID or by sex, although adolescents were more likely to have sleep onset issues than younger children. Sleep problems were positively associated with functional disability and physical symptoms fully mediated this relationship. Emotional symptoms, while associated with sleep problems, evidenced no direct link to functional disability.

Conclusions

Sleep problems are common in pediatric FGIDs and are associated with functional disability through their impact on physical symptoms. Treatments targeting sleep are likely to be beneficial in improving physical symptoms and, ultimately, daily function in pediatric FGIDs.

Effects of a physical activity behavior change intervention on inflammation and related health outcomes in breast cancer survivors: pilot randomized trial

BACKGROUND

The goal of this pilot study was to determine the magnitude and direction of intervention effect sizes for inflammatory-related serum markers and relevant health outcomes among breast cancer survivors (BCSs) receiving a physical activity behavior change intervention compared with usual care.

METHODS

This randomized controlled trial enrolled 28 stage I, II, or IIIA BCSs who were post-primary treatment and not regular exercisers. Participants were assigned to either a 3-month physical activity behavior change intervention group (ING) or usual care group (UCG). Intervention included supervised aerobic (150 weekly minutes, moderate-intensity) and resistance (2 sessions per week) exercise that gradually shifted to home-based exercise. Outcomes were assessed at baseline and 3 months.

RESULTS

Cardiorespiratory fitness significantly improved in the ING versus the UCG (between-group difference = 3.8 mL/kg/min; d = 1.1; P = .015). Self-reported sleep latency was significantly reduced in the ING versus the UCG (between group difference = -0.5; d = -1.2; P = .02) as was serum leptin (between-group difference = -9.0 ng/mL; d = -1.0; P = .031). Small to medium nonsignificant negative effect sizes were noted for interleukin (IL)-10 and tumor necrosis factor (TNF)-α and ratios of IL-6 to IL-10, IL-8 to IL-10, and TNF-α to IL-10, whereas nonsignificant positive effect sizes were noted for IL-6 and high-molecular-weight adiponectin.

CONCLUSIONS

Physical activity behavior change interventions in BCSs can achieve large effect size changes for several health outcomes. Although effect sizes for inflammatory markers were often small and not significant, changes were in the hypothesized direction for all except IL-6 and IL-10.

Extract of Ganoderma lucidum prolongs sleep time in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Ganoderma lucidum (Ling Zhi) is a basidiomycete white-rot macrofungus that has been used as a tranquilizing agent (i.e., An-Shen effect) for the treatment of restlessness, insomnia, and palpitation in China for hundreds of years.

AIM OF THE STUDY

The present study aimed to investigate whether Ganoderma lucidum extract (GLE) influences the sleep of freely moving rats and the potential mechanism.

MATERIALS AND METHODS

Ganoderma lucidum extract was extracted from fruiting bodies of Ganoderma lucidum. Rats were treated with GLE orally for 3 days, and on the third day, electroencephalographic and electromyographic recordings were made for 6h from 9:00 p.m. to 3:00 a.m. in freely moving rats. Sleep parameters were analyzed using SleepSign software. Tumor necrosis factor-α (TNF-α) levels were measured using the enzyme-linked immunosorbent assay.

RESULTS

Three-day administration of GLE significantly increased total sleep time and non-rapid eye movement (NREM) sleep time at a dose of 80 mg/kg (i.g.) without influencing slow-wave sleep or REM sleep in freely moving rats. TNF-α levels were significantly increased concomitantly in serum, the hypothalamus, and dorsal raphe nucleus. The hypnotic effect of GLE (80 mg/kg, i.g.) was significantly inhibited by intracerebroventricular injection of TNF-α antibody (2.5 μg/rat). Co-administration of GLE (40 mg/kg, i.g.) and TNF-α (12.5 ng/rat, i.c.v.), both at ineffective doses, revealed an additive hypnotic effect.

CONCLUSION

These results suggest that GLE has hypnotic effects in freely moving rats. The mechanism by which the extract promoted sleep remains unclear, but this effect appears to be primarily related to the modulation of cytokines such as TNF-α. Furthermore, these data at least partially support the ethnomedical use of Ganoderma lucidum.

Immunological/virological peripheral blood biomarkers and distinct patterns of sleeping quality in chronic hepatitis C patients

The rational of this study we intended to investigate whether the peripheral blood immunological/virological biomarkers were associated with distinct patterns of sleeping quality in patients with chronic hepatitis C-(HCV). Distinct well-established indexes/scores were used to categorize the sleeping quality of HCV patients, including the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale and Fatigue Severity Scores. Our findings demonstrated that HCV patients classified as 'good sleeper' displayed an enhanced frequency of circulating CD8(+) T cells, lower frequency of activated (CD69(+)) neutrophils and eosinophils but enhanced frequency of activated lymphocytes besides lower seric levels of IL-4/IL-8/IL-10 but higher levels of IL-12, besides lower HCV virus load and lower anti-HCV IgG levels. In contrast, HCV patients classified as 'poor sleeper' displayed enhanced levels of activated neutrophils and eosinophils but lower frequency of activated lymphocytes, higher seric levels of IL-6/TNF-α/IL-10 but lower levels of IL-12 besides higher HCV virus load and increased anti-HCV IgG levels. Positive correlation was further confirmed by the relationship between the leucocyte activation status, the cytokine levels, the HCV viral load and the anti-HCV IgG reactivity with the PSQI indexes. Analysis of cytokine signature curves demonstrated that lower frequency of IL-10 was observed in HCV patients classified as 'good sleepers', whereas enhanced frequency of IL-6 was found HCV patients classified as 'poor sleepers'. In conclusion, our data suggest that immunological biomarkers (leucocytes activation status and seric cytokines levels) are likely to be associated with sleeping quality patterns in HCV patients, suggesting their putative use for clinical monitoring purposes.

Biological Consequences of Disturbed Sleep: Important Mediators of Health?

There is an extensive literature regarding the immunological and endocrinological consequences of illness, stress, and psychopathology. Yet only a modest literature is available regarding the potential unfavorable effects of chronic sleep loss/disruption on immune and endocrine pathways or on various aspects of health. Given that humans spend approximately 1/3 of their lives asleep, it seems pertinent to evaluate this necessary yet understudied behavior. The evidence overwhelmingly indicates that "excessive" sleep disruption or poor sleep quality/continuity may subsequently increase risk for adverse health outcomes, as well as mortality. This is thought to occur through dysregulation of biological pathways. While our information addressing the immunological or endocrinological consequences of poor sleep is mounting, the majority of evidence stems from epidemiologic and cross-sectional studies. The immune and endocrine systems are dynamic and constantly in flux. Thus, the methodologies and study designs used to understand how sleep affects these systems needs to be as dynamic. Experimental manipulations and longitudinal evaluations are needed to effectively understand sleep as a risk factor for health. Thus, this paper is a primer in which to highlight the immunological and endocrinological consequences of disrupted or disturbed sleep as well as describe how these relationships may impact overall health. It is also meant to spark an interest for future evaluations of how the behavior of sleep is relevant to health.

A review of sleep disturbance in hepatitis C

Sleep disturbances occur in up to 60% of patients with chronic hepatitis C (CHC) and is often interrelated with comorbid psychiatric disorders. Moreover, neuropsychiatric complications of interferon-alpha during CHC treatment can manifest as sleep problems. Newly diagnosed sleep disturbance occurs in up to 60% and 30% of untreated CHC patients and patients undergoing interferon-alpha therapy, respectively. However, the presentation of insomnia in patients with CHC is influenced by significant psychiatric comorbidity, such as depression, and medical conditions, such as anemia and hypothyroidism. Therefore, prompt recognition using screening tools and exclusion of comorbid conditions contributing sleep pathology can enhance treatment outcomes. Owing to the paucity of studies, treatment recommendations for sleep disorders in CHC patients are derived from recommendations from general sleep disorder treatment guidelines. Further research is needed to elucidate the efficacy of pharmacological and nonpharmacological treatments of sleep disorders in CHC patients.

Disturbed sleep is associated with increased C-reactive protein in young women

Evidence links disturbed sleep with an exaggerated inflammatory response and increased risk of adverse health outcomes. An emerging risk factor for many adverse health outcomes is chronic, low-grade inflammation. An exaggerated inflammatory response could provide a biological link between disturbed sleep and adverse health outcomes. The relationship between sleep and chronic, low-grade inflammation has been sparsely examined in otherwise healthy, young women. We evaluated cross-sectional relationships between self-reported sleep and three inflammatory markers. Participants were community dwelling nonpregnant women (N=43, 28.2+/-5.2 years of age). Measures included the Pittsburgh Sleep Quality Index (PSQI), sleep diaries, and serum levels of IL-6, TNF-alpha and C-reactive protein. Poor sleep quality and continuity were associated with higher CRP levels after controlling for covariates. No significant relationships were observed between PSQI scores and IL-6 or TNF-alpha; sleep duration was not related to any of the inflammatory markers. Poor sleep, in young adulthood, may contribute to the chronic, low-grade inflammation associated with an increased risk for future adverse health outcomes. Future work should longitudinally evaluate how these relationships may affect development of gender-specific diseases in apparently healthy young women.

Disease severity, scratching, and sleep quality in patients with atopic dermatitis

BACKGROUND

The relationship between sleep quality and disease severity in patients with atopic dermatitis has not been clearly defined.

METHODS

Sleep efficiency and scratching were measured over 2 nights by polysomnography, actigraphy, and self-report in 20 adults with atopic dermatitis. Tumor necrosis factor, interleukin (IL)-6, and IL-10 were assayed from a subset of 9 participants.

RESULTS

Sleep measured by actigraphy and polysomnography were strongly associated with each other. Decreased sleep efficiency was associated with increasing disease severity, scratching, and IL-6. Self-reported sleep quality and quality of life were not significantly correlated with either objective sleep measure.

LIMITATIONS

Results in this pilot study await confirmation in a larger investigation.

CONCLUSION

Objective measures but not self-report documented that increasing severity of atopic dermatitis results in more scratching and declining sleep quality. Our data also suggest an important relationship between sleep and IL-6.

Metabolic complications of obstructive sleep apnea syndrome

Obstructive sleep apnea syndrome is a widely prevalent disorder, hallmarked by partial or total upper airway obstruction during sleep. These events fracture sleep integrity resulting in chronic partial sleep deprivation with destructive metabolic sequelae, the focus of this review.

Who are the long sleepers? Towards an understanding of the mortality relationship

While much is known about the negative health implications of insufficient sleep, relatively little is known about risks associated with excessive sleep. However, epidemiological studies have repeatedly found a mortality risk associated with reported habitual long sleep. This paper will summarize and describe the numerous studies demonstrating increased mortality risk associated with long sleep. Although these studies establish a mortality link, they do not sufficiently explain why such a relationship might occur. Possible mechanisms for this relationship will be proposed and described, including (1) sleep fragmentation, (2) fatigue, (3) immune function, (4) photoperiodic abnormalities, (5) lack of challenge, (6) depression, or (7) underlying disease process such as (a) sleep apnea, (b) heart disease, or (c) failing health. Following this, we will take a step back and carefully consider all of the historical and current literature regarding long sleep, to determine whether the scientific evidence supports these proposed mechanisms and ascertain what future research directions may clarify or test these hypotheses regarding the relationship between long sleep and mortality.