Reciprocal Relationship Between Sleep Macrostructure and Evening and Morning Cellular Inflammation in Rheumatoid Arthritis

Active Inflammatory Bowel Disease Is Associated with Short Sleep Duration via Objective Measures

INTRODUCTION

Poor sleep quality has been associated with inflammatory bowel disease (IBD) activity, although studies incorporating actigraphy suggest that the perception of sleep differs rather than objective difference in sleep quality. Short sleep duration has been associated with increased pro-inflammatory cytokines that have been implicated in the pathogenesis of IBD.

METHODS

An observational study incorporated home-based polysomnography that was conducted within twelve weeks of an objective assessment of IBD activity such as calprotectin, colonoscopy, or MRI. Participants completed a survey on subjective measures of sleep quality, clinical IBD activity, depression, and anxiety. Polysomnography results were normalized by standardized results for a healthy population matched by gender and age.

RESULTS

Twenty participants were included in the final analysis. Those with objective evidence of active IBD had shorter stage 2 sleep duration, leading to shorter NREM sleep and total sleep time. Sleep latency was also longer in those with active IBD, leading to worse sleep efficiency-despite no difference in time available for sleep between the two groups. These changes persisted after normalization of polysomnography results by health population age and gender matched norms. Depression scores correlated with sleep latency and stage 2 sleep duration and were associated with objectively active IBD.

CONCLUSIONS

Objectively confirmed active IBD was associated with shorter sleep duration. Observed sleep changes may, in part, relate to coexistent depression. Further research should consider the utility of changes in sleep duration and quality as a means of longitudinally assessing objective IBD activity.

State of the art: Alternative overlap syndrome-asthma and obstructive sleep apnea

In the general population, Bronchial Asthma (BA) and Obstructive Sleep Apnea (OSA) are among the most prevalent chronic respiratory disorders. Significant epidemiologic connections and complex pathogenetic pathways link these disorders via complex interactions at genetic, epigenetic, and environmental levels. The coexistence of BA and OSA in an individual likely represents a distinct syndrome, that is, a collection of clinical manifestations attributable to several mechanisms and pathobiological signatures. To avoid terminological confusion, this association has been named alternative overlap syndrome (vs overlap syndrome represented by the chronic obstructive pulmonary disease-OSA association). This comprehensive review summarizes the complex, often bidirectional links between the constituents of the alternative overlap syndrome. Cross-sectional, population, or clinic-based studies are unlikely to elucidate causality or directionality in these relationships. Even longitudinal epidemiological evaluations in BA cohorts developing over time OSA, or OSA cohorts developing BA during follow-up cannot exclude time factors or causal influence of other known or unknown mediators. As such, a lot of pathophysiological interactions described here have suggestive evidence, biological plausibility, potential or actual directionality. By showcasing existing evidence and current knowledge gaps, the hope is that deliberate, focused, and collaborative efforts in the near-future will be geared toward opportunities to shine light on the unknowns and accelerate discovery in this field of health, clinical care, education, research, and scholarly endeavors.

Analysis of the relationship between sleep-related disorder and systemic immune-inflammation index in the US population

BACKGROUND

The association between sleep-related disorders and inflammation has been demonstrated in previous studies. The systemic immune-inflammation index (SII) is a novel inflammatory index based on leukocytes, but its relationship with sleep-related disorder is unclear. We aimed to investigate the relationship between sleep-related disorder and SII in a nationally representative nonhospitalized sample.

METHODS

Data were obtained from the 2005-2008 National Health and Nutrition Examination Survey (NHANES). Exposure variables included self-reported sleep-related disorders, such as sleep duration, sleep problems, high risk of OSA, and daytime sleepiness. SII and other traditional markers of inflammation were considered as outcome variables, including platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR). Multiple linear regression models were employed to examine the correlation between sleep-related disorders and inflammatory markers. Subgroup interactions were analyzed using likelihood ratio tests, and nonlinear relationships were explored by fitting restricted cubic splines.

RESULTS

A total of 8,505 participants were enrolled in this study. Overall, sleep-related disorders were found to have a stronger association with SII compared to the PLR and NLR. The results of multiple linear regression analysis revealed that participants who experienced sleep problems (β: 21.421; 95% CI 1.484, 41.358), had symptoms of OSA (β: 23.088; 95% CI 0.441, 45.735), and reported daytime sleepiness (β: 30.320; 95% CI 5.851, 54.789) exhibited a positive association with higher SII. For the analysis of other inflammatory markers, we only found that daytime sleepiness was associated with increased NLR levels (β: 0.081; 95% CI 0.002, 0.159).

CONCLUSION

Sleep problems, symptoms of OSA, and daytime sleepiness were found to have a positive association with the SII in US adults. However, further prospective studies are necessary to establish whether there is a causal relationship between these factors.

Revisiting Asthma Obstructive Sleep Apnea Overlap: Current Knowledge and Future Needs

Asthma and obstructive sleep apnea are highly prevalent conditions with a high cost burden. In addition to shared risk factors, existing data suggest a bidirectional relationship between asthma and OSA, where each condition can impact the other. Patients with asthma often complain of sleep fragmentation, nocturnal asthma symptoms, daytime sleepiness, and snoring. The prevalence of OSA increases with asthma severity, as evidenced by multiple large studies. Asthma may lower the threshold for arousal in OSA, resulting in the hypopnea with arousal phenotype. Epidemiologic studies in adults have shown that OSA is associated with worse asthma severity, increased frequency of exacerbation, and poor quality of life. The current literature assessing the relationship among OSA, asthma, and CPAP therapy is heavily dependent on observational studies. There is a need for randomized controlled trials to minimize the interference of confounding shared risk factors.

Disturbance of sleep maintenance, but not sleep duration, activates nuclear factor-κB and signal transducer and activator of transcription family proteins in older adults: sex differences

STUDY OBJECTIVES

Disturbances of sleep maintenance and sleep duration are common in older adults and associated with an increased risk for age-related mortality and morbidity. Converging evidence implicates inflammation as an underlying mechanism, especially in females. However, it is unknown what specific aspects of sleep disturbance impact inflammatory mechanisms in older adults.

METHODS

Using data from community-dwelling older adults who participated in the Sleep Health and Aging Research (SHARE) field study (n = 262, mean age 71.9 ± 8.0 years), we conducted a secondary analysis to examine whether disturbance of sleep maintenance (i.e. greater amount of wake time after sleep onset [WASO]) and sleep duration (i.e. shorter total sleep time [TST]) assessed by sleep diary and actigraphy are associated with greater activation of nuclear factor (NF)-κB and signal transducer and activator of transcription (STAT) family proteins STAT1, STAT3, and STAT5 in peripheral blood monocytic cells. In addition, moderation effects of sex were explored.

RESULTS

Data were available for sleep diary (n = 82), actigraphy (n = 74), and inflammatory signaling and transcriptional measures (n = 132). As assessed by sleep diary, greater amount of WASO (β = 0.39, p < 0.01), but not TST, was associated with higher levels of NF-κB. Whereas diary-assessed sleep measures were not associated with STAT family proteins, a moderation analysis revealed that greater diary-assessed WASO was associated with higher levels of STAT1 (p < 0.05), STAT3 (p < 0.05), and STAT5 (p < 0.01) in females, but not in males. Actigraphy-assessed sleep measures were not associated either with NF-κB or STAT activation.

CONCLUSIONS

In older adults, self-reported disturbance of sleep maintenance assessed by sleep diary was uniquely associated with higher levels of NF-κB, along with higher levels of STAT family proteins in females, but not in males. Our data suggest that improvingself-reported sleep maintenance might mitigate age-related increases in inflammatory signaling and transcriptional pathways, possibly more strongly in females, with the potential to reduce mortality risk in older adults.

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

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

Sleep Disorders Among Individuals With Rheumatoid Arthritis

OBJECTIVE

Self-reported sleep problems are common in rheumatoid arthritis (RA), with potential negative health implications, yet relatively little research has focused on sleep in RA. We examined the prevalence of obstructive sleep apnea (OSA) risk, restless legs syndrome (RLS) symptoms, and short sleep (SS) in a large RA cohort (n = 4,200) and factors associated with each.

METHODS

Data are from FORWARD, The National Databank for Rheumatic Diseases. Validated screening measures assessed OSA risk and RLS symptoms. SS was based on self-reported average sleep time (<6 hours). The Medical Outcomes Study Sleep Problems Index I measured self-reported sleep quality. Multivariable logistic regression models identified independent predictors of sleep disorders and sleep quality and the independent association of OSA risk, RLS symptoms, and SS with self-reported poor sleep quality.

RESULTS

Twenty-one percent (n = 899) had OSA diagnosis or risk, 30% (n = 1,272) had RLS symptoms or diagnosis, and 43% (n = 1,737) reported SS, and RA disease activity was associated with each sleep disorder. Abatacept use was associated with lower odds of RLS and SS. Use of conventional disease-modifying antirheumatic drugs or abatacept was less frequent in the SS group. No medications were associated with OSA in multivariable analyses. Both RLS and SS was associated with worse perceived sleep quality.

DISCUSSION

Almost two-thirds met criteria for at least one sleep disorder. RA disease activity and pain were significantly associated with each sleep condition. Additional research is needed to identify the causal pathway between sleep disorders and RA disease activity and pain and the long-term consequences of sleep disorders in RA.

Characterizing Patterns of Nurses' Daily Sleep Health: a Latent Profile Analysis

BACKGROUND

Nursing is a demanding occupation characterized by dramatic sleep disruptions. Yet most studies on nurses' sleep treat sleep disturbances as a homogenous construct and do not use daily measures to address recall biases. Using person-centered analyses, we examined heterogeneity in nurses' daily sleep patterns in relation to psychological and physical health.

METHODS

Nurses (N = 392; 92% female, mean age = 39.54 years) completed 14 daily sleep diaries to assess sleep duration, efficiency, quality, and nightmare severity, as well as measures of psychological functioning and a blood draw to assess inflammatory markers interleukin-6 (IL-6) and C-reactive protein (CRP). Using recommended fit indices and a 3-step approach, latent profile analysis was used to identify the best-fitting class solution.

RESULTS

The best-fitting solution suggested three classes: (1) "Poor Overall Sleep" (11.2%), (2) "Nightmares Only" (8.4%), (3) "Good Overall Sleep" (80.4%). Compared to nurses in the Good Overall Sleep class, nurses in the Poor Overall Sleep or Nightmares Only classes were more likely to be shift workers and had greater stress, PTSD symptoms, depression, anxiety, and insomnia severity. In multivariate models, every one-unit increase in insomnia severity and IL-6 was associated with a 33% and a 21% increase in the odds of being in the Poor Overall Sleep compared to the Good Overall Sleep class, respectively.

CONCLUSION

Nurses with more severe and diverse sleep disturbances experience worse health and may be in greatest need of sleep-related and other clinical interventions.

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

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

Examining Relationships between Sleep Physiology and the Gut Microbiome in Pre-Clinical and Translational Research: A Scoping Review Protocol (Preprint)

Background

Objective

Methods

Results

Conclusions

Trial Registration

International Registered Report Identifier (IRRID)

Sleep disorders and vascular responsiveness in patients with rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is the most common systemic autoimmune disease characterized by chronic systemic inflammation. Half of the deaths of patients with RA are due to cardiovascular diseases (CVD), considered to be 1.5 to -2.0-fold that in the general population. Patients with RA also experience poor sleep, which by itself is associated with endothelial dysfunction, CVD events and sudden death. Our aim was to study the mechanistic pathways and the correlations between sleep efficiency and vascular reactivity of patients with RA.

METHODS AND RESULTS

A prospective study that evaluated quality of sleep using ACTi Graphs, vascular inflammation and endothelial function of 18 patients with RA. Inflammation was studied by levels of E-selectin, intercellular adhesion molecule 1 (ICAM-1) and NO in serum. Endothelial function was studied using the brachial artery plethysmography method. Eighteen RA patients (aged 57.56 ± 13.55 years; 16 women) with a long-standing active RA: Eight patients had impaired sleep efficiency and 10 had a good sleep efficiency. Those who had an impaired sleep had larger baseline diameters of the brachial artery (0.39 ± 0.08 cm vs. 0.32 ± 0.04 cm; P = 0.02). Negative correlations were found between baseline brachial artery diameter and sleep efficiency (P = 0.01), and with NO level (P = 0.04). Stepwise regression found that brachial artery diameter at baseline and NO level could predict sleep efficiency (r²  = 0.543, P = 0.01).

CONCLUSION

Vascular reactivity could predict quality of sleep in patients with RA. Quality of sleep may serve as an independent CVD risk factor in patients with RA.

Sleep Inconsistency and Markers of Inflammation

Objective: Poor sleep is associated with higher levels of inflammatory biomarkers. Conventionally, higher average time awake, lower average time asleep, and lower sleep efficiency define poor sleep. Recent research suggests that, in addition to average sleep, sleep inconsistency is an important indicator of sleep dysfunction. The current study sought to extend our knowledge of the relationship between sleep and inflammation through an examination of sleep inconsistency and inflammatory biomarkers. Methods: Secondary analyses of the Survey of Midlife in the United States (MIDUS) sleep study were conducted. Five hundred thirty-three individuals completed nightly sleep diaries, actigraphy, and underwent a blood draw for the inflammatory biomarkers C-reactive protein, interleukin-6, and fibrinogen. Sleep inconsistency was derived from 7 consecutive nights of assessment and was operationalized as nightly fluctuations in the following variables: terminal wakefulness, number of awakenings, time in bed, sleep onset latency, and wake after sleep onset. Structural equation modeling was used to examine the influence of a latent average sleep and a latent sleep inconsistency variable on a latent inflammation variable. Models were subsequently adjusted for age, sex, BMI, health, and medication. Stratified models by sex were also analyzed. Results: The average sleep model would not converge. The sleep inconsistency model fit the data well. A significant positive association between the latent factors sleep inconsistency and inflammation was observed (β = 10.18, SE = 4.40, p = 0.021), suggesting inconsistent sleep is associated with higher levels of inflammatory biomarkers. When stratified by sex, the association between the latent sleep inconsistency factor and inflammation was significant for women (β = 1.93, SE = 0.82, p = 0.018), but not men (β = 0.20, SE = 0.35, p = 0.566). The association between sleep inconsistency and inflammation weakened following multivariate adjustment (β = 6.23, SE = 3.71, p = 0.093). Conclusions: Inconsistent sleep may be an associated feature of inflammatory dysfunction, especially in women. Future studies should build upon this preliminary work and examine these associations longitudinally and through treatment trials.

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.

Rheumatoid arthritis is associated with negatively variable impacts on domains of sleep disturbances: evidence from a systematic review and meta-analysis

The aim of this study was to identify the impact of rheumatoid arthritis (RA) on specific sleep quality domains and to determine its prevalence. A systematic literature search was performed on PubMed, Web of Science, Cochrane Library, and Embase until January 2018 to obtain eligible studies. Score of the Pittsburgh Sleep Quality Index (PSQI) was used as the outcome measurement, and weight mean differences (WMD) with 95% confidence intervals (CI) were calculated. In total, eight studies were eligible for inclusion criteria, comprising 658 RA patients and 485 healthy controls. In this meta-analysis, each domain of the PSQI score: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disorders, use of sleep medication, daytime dysfunction and the total score were higher in RA patients than healthy controls. In addition, the relative risk of sleep disturbances among people with RA was 2.37 (95% CI: 1.80, 3.11) compared with people without RA.In conclusion, RA patients scored higher in each dimension of PSQI, and sleep disturbances was more prevalent in RA patients than in controls. Further research is needed to identify effective strategies for preventing and treating sleep disturbances among RA patients.

Sleep and inflammation: partners in sickness and in health

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

Alzheimer's disease pathogenesis: The role of disturbed sleep in attenuated brain plasticity and neurodegenerative processes

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by cognitive impairments. The classical symptoms of the disease include gradual deterioration of memory and language. Epidemiological studies indicate that around 25-40% of AD patients have sleep-wake cycle disturbances. Importantly, a series of studies suggested that the relationship between AD and sleep disturbance may be complex and bidirectional. Indeed, accumulation of the extracellular neuronal protein amyloid-beta (Aβ) leads to altered sleep-wake behavior in both mice and humans. At the same time, disturbances of the normal sleep-wake cycle may facilitate AD pathogenesis. This paper will review the mechanisms underlying this potential interrelated connection including locus coeruleus damage, reductions in orexin neurotransmission, alterations in melatonin levels, and elevated cytokine levels. In addition, we will also highlight how both the development of AD and sleep disturbances lead to changes in intracellular signaling pathways involved in regulating neuronal plasticity and connectivity, particularly extremes in cofilin phosphorylation. Finally, current pharmacological and nonpharmacological therapeutic approaches will be discussed.

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.

A new design for a chronological release profile of etodolac from coated bilayer tablets: In-vitro and in-vivo assessment

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Bilayer tablet formulation of etodolac was formulated with a fast and a sustained release layers.

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Compression of optimized fast and sustained release layers into a bilayer tablet.

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Three successive coating layers of Opadry®, HPMC and Surelease® were applied on bilayer tablet.

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In-vitro dissolution showed a lag time of 4 h followed by a prolonged release over 24 h.

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Optimized formulation showed a prolonged anti inflammatory effect in rats.

Repeated dose medication usually maximizes adverse effects, while sustained release systems did not offer a fast onset of action. Etodolac was formulated to enable pulsatile and sustained drug release, which was chronologically more suitable as an anti-inflammatory drug. Eudragit® RSPO, Eudragit® RLPO, and HPMC K15M were added in the sustained release layer and tried in different ratios. Croscarmellose sodium or sodium starch glycolate were used as superdisintegrants for the fast release layer offering the loading dose for rapid onset of drug action. Bilayer tablets were successively coated with Opadry®II, HPMC K4M and E5 (1:40), and Surelease®. All formulations complied with the Pharmacopeial standards for post-compression parameters. In-vitro release profile illustrated a lag-time of 4 h followed by a rapid loading dose release for 2 h. A prolonged steady state release with a t_1/2 of 11 h lastly occurred. The coated bilayer tablet showed pulsatile and sustained release effects in rats. The licking time and swelling degree were tested and results demonstrated significant difference (P < 0.05) between the sustained anti-inflammatory action of formulation C1 compared to other groups. Therefore the new chronological design could provide a consistent drug release over 24 h with good protection against associated symptoms of gastric release.

Prospective Analyses of Cytokine Mediation of Sleep and Survival in the Context of Advanced Cancer

OBJECTIVE

The aims of this study were to examine the potential association between sleep problems, symptom burden, and survival in patients with advanced cancer.

METHODS

A prospective study of 294 patients with gastrointestinal cancer administered questionnaires assessing sleep, depression, anxiety, stress, pain, fatigue, and health-related quality of life. Serum levels of cytokines including interleukin (IL)-1α, IL-1β, tumor necrosis factor α, IL-10, IL-2, and interferon-γ were measured to assess biological mediation between sleep and survival. Survival was measured as time from diagnosis to death.

RESULTS

Fifty-nine percent of patients reported poor sleep quality, 53% reported poor sleep efficiency, 39% reported sleep latency greater than 30 minutes, and 45% reported sleeping less than 6 hours or greater than 10 hours. We found a significant association between sleep duration and symptom burden. Shorter sleep duration was significantly associated with higher levels of fatigue (r = -0.169, p = .01), pain (r = -0.302, p = .01), anxiety (r = -0.182, p = .01), depression (r = -0.172, p = .003), and lower levels of quality of life (r = 0.240, p = .01). After adjustment for demographic, psychological, and disease-specific factors, short sleep duration was associated with reduced survival (hazard ratio [HR] linear = 0.485, 95% confidence interval = 0.275-0.857) and there was also evidence for a quadratic pattern (HR quadrati = 1.064, 95% confidence interval = 1.015-1.115) suggesting a curvilinear relationship between sleep duration and survival. Interleukin 2 was the only cytokine significantly related to survival (HR = 1.01, p = .003) and sleep duration (β = -30.11, p = .027). When of IL-2 was added to the multivariable model, short and long sleep (β = -0.557, p = .097; β = 0.046, p = .114) were no longer significantly related to survival, suggesting mediation by IL-2.

CONCLUSION

Sleep duration was associated with symptom burden and poorer survival and IL-2 was found to mediate the association between sleep and survival. Screening and treatment of sleep problems in patients diagnosed with cancer are warranted.

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.

Fatigue in Rheumatoid Arthritis

PURPOSE OF REVIEW

The purpose of this study was to review the current information on fatigue in rheumatoid arthritis (RA).

RECENT FINDINGS

Severe fatigue is common among individuals with RA and has a significant impact on quality of life (QOL). RA-related factors (e.g., inflammation, pain) are associated with greater fatigue, but other factors, such as obesity, physical inactivity, sleep disturbance, and depression, explain the majority of variation in fatigue. Medications targeting RA have little effect on fatigue. Instead, the most effective interventions seem to address non-RA-specific factors such as physical inactivity or use cognitive behavioral approaches. No recommendations have been made for tools to measure fatigue in RA, leading to potential difficulty comparing studies. Although fatigue has great impact on patients' QOL, effective interventions that are feasible for broad dissemination remain elusive. Additional multi-faceted research is needed to identify modifiable sources of fatigue. Such research would be enhanced by harmonization of fatigue measurement across studies.

Sleep Health: Reciprocal Regulation of Sleep and Innate Immunity

Sleep disturbances including insomnia independently contribute to risk of inflammatory disorders and major depressive disorder. This review and overview provides an integrated understanding of the reciprocal relationships between sleep and the innate immune system and considers the role of sleep in the nocturnal regulation of the inflammatory biology dynamics; the impact of insomnia complaints, extremes of sleep duration, and experimental sleep deprivation on genomic, cellular, and systemic markers of inflammation; and the influence of sleep complaints and insomnia on inflammaging and molecular processes of cellular aging. Clinical implications of this research include discussion of the contribution of sleep disturbance to depression and especially inflammation-related depressive symptoms. Reciprocal action of inflammatory mediators on the homeostatic regulation of sleep continuity and sleep macrostructure, and the potential of interventions that target insomnia to reverse inflammation, are also reviewed. Together, interactions between sleep and inflammatory biology mechanisms underscore the implications of sleep disturbance for inflammatory disease risk, and provide a map to guide the development of treatments that modulate inflammation, improve sleep, and promote sleep health.