The Pain of Sleep Loss: A Brain Characterization in Humans

Temazepam or Melatonin Versus Placebo for the Treatment of Insomnia in Advanced Cancer: A Three-Arm, Double-Blind, Phase III, Multicenter, Randomized Clinical Trial

Background: Sleep disturbance has a prevalence of 30-78% in patients with advanced cancer. While pharmacotherapy is common, randomized controlled studies (RCTs) investigating available agents are limited. This study examines the efficacy and safety of temazepam or melatonin versus placebo for sleep in advanced cancer. Methods: This is a multicenter, randomized, double-blind, placebo-controlled study of temazepam, melatonin prolonged release (PR) or placebo for insomnia in patients with advanced cancer, and an insomnia severity index (ISI) score of >11. Results: Twenty-one participants were randomized: nine to temazepam, eight to melatonin, and four to placebo. Baseline characteristics between groups were similar. The adjusted mean difference in day 8 ISI score versus placebo was -9.1 (95% confidence interval [CI] -17.5, 0.7, p = 0.04) for temazepam and -9.6 (95% CI -18,-1.2, p = 0.03) for melatonin PR. There was no improvement in global quality of life. Both agents were well tolerated. Conclusion: Temazepam and melatonin PR were associated with a clinically significant improvement in patient-reported insomnia severity compared with placebo. Findings need confirmation with larger patient numbers.

The Impact of Menstrual Disorders on Sleep Quality in Adolescents: An Observational Study

STUDY OBJECTIVE

Premenstrual syndrome (PMS), dysmenorrhea, and abnormal uterine bleeding are frequent gynecological problems in adolescent girls. Studies show that sleep disorders and menstrual cycle irregularities are common conditions and indicate that they may occur together. Studies on the relationship between sleep quality and menstruation are mostly available for late adolescents (17 years and older) and young adult age groups. Our study aims to evaluate this relationship in adolescents aged 12-18.

METHODS

A survey study was structured and consisted of 4 sections. The first section includes anthropometric measurements and medical history of the participants; the second section includes "menstruation and menstruation symptoms history"; the third section includes "The Sleep Quality Scale and Sleep Variable Questionnaire"; and the fourth section includes the "Premenstrual Syndrome Assessment Scale" (PMSAS). Our survey was applied to those who visited the adolescent medicine outpatient clinic.

RESULTS

The Sleep Quality Scale score was significantly lower in those with high PMSAS scores (P < .001). The participants who had dysmenorrhea and experienced other symptoms during menstruation had significantly lower SQS scores and sleep efficiency (SE) (P < .001). There was no significant difference between heavy menstrual bleeding, defined as lasting more than 7 days, requiring more than 5-6 pads/tampons per day, and SE/quality (P > .05).

CONCLUSION

According to our study, dysmenorrhea and the presence of PMS may negatively affect the sleep quality of adolescents. Health professionals dealing with young people should take into account the effects of menstrual problems on sleep quality and offer appropriate support/treatment options.

Modulating the Pronociceptive Effect of Sleep Deprivation: A Possible Role for Cholinergic Neurons in the Medial Habenula

Sleep deprivation has been shown to exacerbate pain sensitivity and may contribute to the onset of chronic pain, yet the precise neural mechanisms underlying this association remain elusive. In our study, we explored the contribution of cholinergic neurons within the medial habenula (MHb) to hyperalgesia induced by sleep deprivation in rats. Our findings indicate that the activity of MHb cholinergic neurons diminishes during sleep deprivation and that chemogenetic stimulation of these neurons can mitigate the results. Interestingly, we did not find a direct response of MHb cholinergic neurons to pain stimulation. Further investigation identified the interpeduncular nucleus (IPN) and the paraventricular nucleus of the thalamus (PVT) as key players in the pro-nociceptive effect of sleep deprivation. Stimulating the pathways connecting the MHb to the IPN and PVT alleviated the hyperalgesia. These results underscore the important role of MHb cholinergic neurons in modulating pain sensitivity linked to sleep deprivation, highlighting potential neural targets for mitigating sleep deprivation-induced hyperalgesia.

Spinal bestrophin-1 and anoctamin-1 channels have a pronociceptive role in the tactile allodynia induced by REM sleep deprivation in rats

Bestrophin-1 and anoctamin-1 are members of the calcium-activated chloride channels (CaCCs) family and are involved in inflammatory and neuropathic pain. However, their role in pain hypersensitivity induced by REM sleep deprivation (REMSD) has not been studied. This study aimed to determine if anoctamin-1 and bestrophin-1 are involved in the pain hypersensitivity induced by REMSD. We used the multiple-platform method to induce REMSD. REM sleep deprivation for 48 h induced tactile allodynia and a transient increase in corticosterone concentration at the beginning of the protocol (12 h) in female and male rats. REMSD enhanced c-Fos and α2δ-1 protein expression but did not change activating transcription factor 3 (ATF3) and KCC2 expression in dorsal root ganglia and dorsal spinal cord. Intrathecal injection of CaCCinh-A01, a non-selective bestrophin-1 blocker, and T16Ainh-A01, a specific anoctamin-1 blocker, reverted REMSD-induced tactile allodynia. However, T16Ainh-A01 had a higher antiallodynic effect in male than female rats. In addition, REMSD increased bestrophin-1 protein expression in DRG but not in DSC in male and female rats. In marked contrast, REMSD decreased anoctamin-1 protein expression in DSC but not in DRG, only in female rats. Bestrophin-1 and anoctamin-1 promote pain and maintain tactile allodynia induced by REM sleep deprivation in both male and female rats, but their expression patterns differ between the sexes.

The new science of sleep: From cells to large-scale societies

In the past 20 years, more remarkable revelations about sleep and its varied functions have arguably been made than in the previous 200. Building on this swell of recent findings, this essay provides a broad sampling of selected research highlights across genetic, molecular, cellular, and physiological systems within the body, networks within the brain, and large-scale social dynamics. Based on this raft of exciting new discoveries, we have come to realize that sleep, in this moment of its evolution, is very much polyfunctional (rather than monofunctional), yet polyfunctional for reasons we had never previously considered. Moreover, these new polyfunctional insights powerfully reaffirm sleep as a critical biological, and thus health-sustaining, requisite. Indeed, perhaps the only thing more impressive than the unanticipated nature of these newly emerging sleep functions is their striking divergence, from operations of molecular mechanisms inside cells to entire group societal dynamics.

A noradrenergic pathway for the induction of pain by sleep loss

An epidemic of sleep loss currently affects modern societies worldwide and is implicated in numerous physiological disorders, including pain sensitization, although few studies have explored the brain pathways affected by active sleep deprivation (ASD; e.g., due to recreation). Here, we describe a neural circuit responsible for pain sensitization in mice treated with 9-h non-stress ASD. Using a combination of advanced neuroscience methods, we found that ASD stimulates noradrenergic inputs from locus coeruleus (LCNA) to glutamatergic neurons of the hindlimb primary somatosensory cortex (S1HLGlu). Moreover, artificial inhibition of this LCNA→S1HLGlu pathway alleviates ASD-induced pain sensitization in mice, while chemogenetic activation of this pathway recapitulates the pain sensitization observed following ASD. Our study thus implicates activation of the LCNA→S1HLGlu pathway in ASD-induced pain sensitization, expanding our fundamental understanding of the multisystem interplay involved in pain processing.

Exploring the therapeutic potential of cannabidiol for sleep deprivation-induced hyperalgesia

Hyperalgesia resulting from sleep deprivation (SD) poses a significant a global public health challenge with limited treatment options. The nucleus accumbens (NAc) plays a crucial role in the modulation of pain and sleep, with its activity regulated by two distinct types of medium spiny neurons (MSNs) expressing dopamine 1 or dopamine 2 (D1-or D2) receptors (referred to as D1-MSNs and D2-MSNs, respectively). However, the specific involvement of the NAc in SD-induced hyperalgesia remains uncertain. Cannabidiol (CBD), a nonpsychoactive phytocannabinoid, has demonstrated analgesic effects in clinical and preclinical studies. Nevertheless, its potency in addressing this particular issue remains to be determined. Here, we report that SD induced a pronounced pronociceptive effect attributed to the heightened intrinsic excitability of D2-MSNs within the NAc in Male C57BL/6N mice. CBD (30 mg/kg, i.p.) exhibited an anti-hyperalgesic effect. CBD significantly improved the thresholds for thermal and mechanical pain and increased wakefulness by reducing delta power. Additionally, CBD inhibited the intrinsic excitability of D2-MSNs both in vitro and in vivo. Bilateral microinjection of the selective D2 receptor antagonist raclopride into the NAc partially reversed the antinociceptive effect of CBD. Thus, these findings strongly suggested that SD activates NAc D2-MSNs, contributing heightened to pain sensitivity. CBD exhibits antinociceptive effects by activating D2R, thereby inhibiting the excitability of D2-MSNs and promoting wakefulness under SD conditions.

Association between sleep dysfunction and Patient-Reported Outcomes Measurement Information System scores in patients with rotator cuff tears

OBJECTIVES

The purpose of this study was to utilize Patient-Reported Outcomes Measurement Information System (PROMIS) sleep scores to determine the prevalence of sleep dysfunction and its association with other PROMIS scores in patients with rotator cuff tears (RCT).

METHODS

Patients were retrospectively identified using the International Classification of Diseases-10 codes for RCT pathology, and PROMIS outcomes were assessed at multiple visits between November 2017 and February 2020. Generalized linear mixed effects models were fitted with PROMIS sleep score as the predictor variable and other PROMIS scores as the response variable. Additionally, models were fit using a clinically significant dichotomization of PROMIS sleep scores to assess differences in average PROMIS scores.

RESULTS

The study cohort included 481 patients, 201 (41.8 ​%) of whom had disrupted sleep at first visit. A higher percentage of those with disrupted sleep at first visit were female, nonwhite, and not married compared to those with normal sleep. PROMIS scores at first visit differed by sleep category. Higher PROMIS sleep scores were associated with higher anxiety, depression, fatigue, pain intensity, and pain interference scores and lower physical function, social participation, and upper extremity scores. Relationships were similar when dichotomous PROMIS sleep scores were considered.

CONCLUSION

There was a high prevalence of sleep dysfunction in patients with RCT. Sleep disturbance is associated with increased anxiety, depression, fatigue, pain intensity, pain interference and decreased physical function, social participation, and upper extremity function in patients with RCTs.

LEVEL OF EVIDENCE III

Retrospective Cohort Study.

Clinical Phenotypes Supporting the Relationship Between Sleep Disturbance and Impairment of Placebo Effects

Lack of good sleep or insomnia can lead to many health issues, including an elevated risk of cardiovascular disease, obesity, fatigue, low mood, and pain. While chronic pain negatively impacts sleep quality, the relationship between descending pain modulatory systems like placebo effects and sleep quality is not thoroughly known. We addressed this aspect in a cross-sectional study in participants with chronic pain. Placebo effects were elicited in a laboratory setting using thermal heat stimulations delivered with visual cues using classical conditioning and verbal suggestions. We estimated the levels of insomnia severity with the Insomnia Severity Index and the sleep quality with the Pittsburg Sleep Quality Index. The previous night's sleep continuity was assessed as total sleep time, sleep efficiency, and sleep midpoint the night before the experiment. 277 people with chronic pain and 189 pain-free control individuals participated. Participants with chronic pain and insomnia showed smaller placebo effects than those with chronic pain without insomnia. Similarly, poor sleep quality was associated with reduced placebo effects among participants with chronic pain. Clinical anxiety measured by Depression Anxiety Stress Scales partially mediated these effects. In contrast, placebo effects were not influenced by the presence of insomnia or poor sleep quality in pain-free participants. Sleep continuity the night before the experiment did not influence the placebo effects. Our results indicate that participants who experience insomnia and/or poor sleep quality and chronic pain have smaller placebo effects, and that the previous night sleep continuity does not influence the magnitude of placebo effects. PERSPECTIVE: This study examined the relationship between sleep disturbances and experimentally induced placebo effects. We found that individuals with chronic pain who experience insomnia and poor sleep quality demonstrated reduced placebo effects compared to their counterparts with good sleep quality and no insomnia.

Pathways of sleep disturbances in juvenile idiopathic arthritis and recommendations for clinical management approaches: A critical review

Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease affecting young people. It has a profound impact on their physical, mental and social lives, leading to long-term disability. With the growing awareness of the importance of sleep in all areas of functioning in young people, an emerging literature has drawn attention to the role of sleep in the pathogenesis of JIA. Sleep disturbances in children and adolescents with JIA arise from a wide range of symptoms and pathways, leading to a vicious cycle that exacerbates subclinical inflammation, symptoms and disease progression. Putative factors contributing to sleep disturbances include chronic inflammation, JIA-associated sleep disorders, JIA symptoms (e.g. pain), psychological comorbidities and potential circadian disruption, which may be exacerbated by the transition to adolescence. Here, we review these pathways and advocate key strategies and alternatives for sleep management in young people with JIA in clinical settings. We identify gaps in knowledge and suggest future directions to improve our understanding of JIA sleep disorders, including clinical trials investigating potential strategies to improve sleep health in this young population.

MS care: integrating advanced therapies and holistic management

Lifestyle and environmental factors are key determinants in disease causality and progression in neurological conditions, including multiple sclerosis (MS). Lack of exercise, poor diet, tobacco smoking, excessive alcohol intake, social determinants of health, concomitant medications, poor sleep and comorbidities can exacerbate MS pathological processes by impacting brain health and depleting neurological reserves, resulting in more rapid disease worsening. In addition to using disease-modifying therapies to alter the disease course, therapeutic strategies in MS should aim to preserve as much neurological reserve as possible by promoting the adoption of a "brain-healthy" and "metabolically-healthy" lifestyle. Here, we recommend self-regulated lifestyle modifications that have the potential to improve brain health, directly impact on disease progression and improve outcomes in people with MS. We emphasise the importance of self-management and adopting a multidisciplinary, collaborative and person-centred approach to care that encompasses the healthcare team, family members and community support groups.

Dysmenorrhea and Sleep: A Review

This review encompasses the clinical features and relevance to investigate sleep in women with dysmenorrhea. Dysmenorrhea is a prevalent gynecologic dysfunction that affects the social and professional lives of women. It can occur at every menstrual cycle, depending on the cause and psychologic factors. Studies have reported poor sleep and insomnia symptoms in dysmenorrhea condition, which may intensify the dysmenorrhea manifestation and interfere negatively to its treatment. There is an urgent need to identify the main cause of this dysfunction and provide efficient treatments to minimize the detrimental effects of dysmenorrhea in quality of life of these women.

Sleep Disorders and Chronic Pain Syndromes in the Pediatric Population

Sleep problems are widespread in children and adolescents suffering from chronic pain disorders. Sleep loss intensifies the experience of pain and is detrimental to the budding self-efficacy of a young individual with limitless horizons. Addressing sleep disorders may prevent the chronification of pain and prevent adverse health outcomes, such as functional impairment, psychiatric comorbidities and overall poor quality of life. This review will explore the cyclical nature between sleep, pain and mood, as well as the functional impact of this relationship on children and adolescents. There will be a discussion about sleep assessment and diagnostic testing, followed by a description of sleep disturbances found in specific pain conditions, ranging from headache, musculoskeletal/abdominal pain, to rheumatologic disorders. Finally, there will be a brief review of pharmacologic and behavioral interventions designed to improve sleep quality, and when possible, to alleviate pain.

Relationship of Sleep Health and Endoscopic Disease Activity in Inflammatory Bowel Disease: Endoscopic Disease Activity and Sleep

Among adults with inflammatory bowel disease (IBD), self-reported sleep disturbances are associated with active symptoms, but the association between sleep measures and endoscopic disease activity is unknown. This study aimed to (1) compare sleep-wake behaviors among IBD patients based on endoscopic and clinical disease activity and (2) describe associations between actigraphy, self-reported sleep measures, and symptoms of fatigue, anxiety, and depression. Participants wore a wrist actigraph for 10 consecutive days and completed self-reported sleep questionnaires (Pittsburgh Sleep Quality Index [PSQI] and Patient-Reported Outcome Measures System [PROMIS] Sleep Disturbance and Sleep Interference questionnaires). Clinical and endoscopic disease activity were assessed. Based on actigraphic recordings ( n = 26), average total nighttime sleep was 437 minutes and sleep efficiency was 84%. Objective sleep measures did not differ based on endoscopic or clinical disease activity. Individuals with active clinical disease had higher PROMIS Sleep Disturbance (57.3 vs. 49.7, d = 1.28) and PROMIS Sleep-Related Impairment (58.1 vs. 52.8, d = 0.51) compared with those with inactive clinical disease. Self-reported sleep was significantly associated with anxiety, depression, and fatigue. Further research is needed to better characterize the relationship between sleep and endoscopic disease activity, and determine underlying mechanisms related to poor sleep in the IBD population.

The endocannabinoid N-arachidonoyl dopamine is critical for hyperalgesia induced by chronic sleep disruption

Chronic pain is highly prevalent and is linked to a broad range of comorbidities, including sleep disorders. Epidemiological and clinical evidence suggests that chronic sleep disruption (CSD) leads to heightened pain sensitivity, referred to as CSD-induced hyperalgesia. However, the underlying mechanisms are unclear. The thalamic reticular nucleus (TRN) has unique integrative functions in sensory processing, attention/arousal and sleep spindle generation. We report that the TRN played an important role in CSD-induced hyperalgesia in mice, through its projections to the ventroposterior region of the thalamus. Metabolomics revealed that the level of N-arachidonoyl dopamine (NADA), an endocannabinoid, was decreased in the TRN after CSD. Using a recently developed CB1 receptor (cannabinoid receptor 1) activity sensor with spatiotemporal resolution, CB1 receptor activity in the TRN was found to be decreased after CSD. Moreover, CSD-induced hyperalgesia was attenuated by local NADA administration to the TRN. Taken together, these results suggest that TRN NADA signaling is critical for CSD-induced hyperalgesia.

Bidirectional Links of Daily Sleep Quality and Duration With Pain and Self-rated Health in Older Adults' Daily Lives

BACKGROUND

Sleep and health perceptions, such as self-ratings of pain and health are closely linked. However, the temporal ordering of such associations is not well understood, and it remains unclear whether sleep quality and sleep duration show similar or differential associations with health perceptions.

METHODS

We used ecological momentary assessment data from 123 young-old (66-69 years, 47% women) and 47 old-old adults (84-90 years, 60% women). Across 7 consecutive days, participants reported their sleep quality and sleep duration each morning and rated their momentary pain and health 6 times per day. We applied dynamic structural equation models to examine bidirectional links of morning reports of sleep quality and duration with daily levels of self-rated pain and health.

RESULTS

In line with the hypotheses, results showed that when participants reported better sleep quality than what is typical for them, they reported less pain and better self-rated health on the day that followed. Longer sleep duration was not linked with subsequent pain or self-rated health. On days when people rated their health as better than usual, they reported better sleep quality but not longer sleep duration the following night. These associations were not moderated by age, gender, or chronic pain.

CONCLUSION

Findings suggest that in old age, sleep quality is more relevant for health perceptions than sleep duration. Associations between sleep quality and self-rated health seem to be bidirectional; daily pain was linked to prior but not subsequent sleep quality.

Lengthening sleep reduces pain in childhood arthritis: a crossover randomised controlled trial

OBJECTIVES

Juvenile idiopathic arthritis (JIA) is a common chronic childhood disease and chronic pain is a debilitating feature. A strong link has been shown between poor sleep and pain in JIA. However, the causal direction is unknown. This study's aim was to determine if, in adolescents with JIA, a recommended healthful sleep duration leads to reductions in pain when compared with the restricted sleep (RS) duration that is commonly seen.

METHODS

Patients with JIA (12-18 years old; pain score of ≥1 on a visual analogue scale) participated in a randomised, crossover sleep manipulation protocol. The 3-week protocol comprised a baseline week (BL), a week with healthy sleep duration (HSD; 9.5 hours in bed/night) and a RS week (RS; 6.5 hours in bed/night). After BL, participants were randomly assigned to either HSD or RS, and then crossed over to the other condition. Pain was self-assessed using the iCanCope with Pain app. We used Bayesian hierarchical models to estimate the effect of sleep duration on pain.

RESULTS

Participants (n=31; mean age=15.0±1.8 years) averaged 1.4 (95% credible interval (CrI) 1.2-1.6) more hours of sleep per night during HSD relative to RS. Compared with RS, HSD resulted in a favourable effect on pain scores (OR 0.61, 95% CrI 0.39-0.95).

CONCLUSION

It is possible to have adolescents with childhood arthritis get a healthier sleep duration, and this longer sleep results in reduced pain. These findings complement prior correlational studies and confirm a causal relationship between reduced sleep duration and increased pain.

TRIAL REGISTRATION NUMBER

NCT04133662.

The experience of pain and its ontological modelling from a philosophical point of view: Phenomenological description and ontological revision of the McGill Pain Questionnaire

The aim of the article is to identify, on the basis of the phenomenological and ontological analysis of the experience of pain and the ways in which this experience is expressed in natural language, an ontological modelling of the language of pain and, at the same time, a revision of the traditional version of the McGill questionnaire. The purpose is to provide a different characterisation and an adequate evaluation of the phenomenon of pain, and, consequently, an effective measure of the actual experience of the suffering subject.

The impact of sleep disturbance on pain perception: A systematic review examining the moderating effect of sex and age

Females have increased pain sensitivity and are more vulnerable to chronic pain conditions. Sleep disturbances are comorbid with chronic pain and exacerbate pain symptoms. Different types of sleep disturbance affect pain perception distinctly, but it is not clear if these effects are equal in men and women. This systematic review investigated potential differences in how sleep disturbance affects pain in males and females. We searched EBSCO, MEDLINE, Psych INFO, Science Direct, and Web of Science from January 2001 to November 2022 and found 38 studies with 978 participants. Separate random-effects models were used to estimate the pooled effect sizes based on standardized mean differences (SMDs) of experimental sleep disturbance paradigms on various pain outcomes. Sex moderated the effect of sleep disturbance on pain facilitation (SMD = 0.13; 95%CI: 0.004 to 0.022; p=.009) and pain inhibition (SMD = 0.033; 95%CI: 0.011 to 0.054; p=.005), with increased facilitation and decreased inhibition in females, but the opposite effect in males. Further, age moderated the effects of total sleep deprivation (SMD = -0.194; 95%CI -0.328 to -0.060; p=.008) on pain sensitivity and fragmented sleep (SMD = -0.110; 95%CI: 0.148 to -0.072; p<.001) on pain threshold. While the moderating effect of sex and age on the sleep-pain relationship was small, these factors need to be considered in future sleep-pain research.

Effects of eyeshades in sleep quality and pain after surgery in school-age children with supracondylar humeral fractures

Objective

This study aimed to explore the effects of eye masks on the sleep quality and pain of children over 5 years old with humeral supracondylar fracture after surgery.

Methods

Fifty children with humeral supracondylar fracture who underwent closed reduction and percutaneous pinning (CRPP) in the Pediatric orthopaedic Department of a provincial hospital in China from February 2020 to December 2021 were selected. The children were randomly divided into the experimental group (n = 25) and the control group (n = 25). Children in the control group were given routine sleep care, and the children in the experimental group were given a sleep intervention with eye masks for three nights after surgery. The Pittsburgh Sleep Quality Index was used to evaluate the sleep quality of the children. The Children's Pain Behaviour Scale was used to evaluate the pain of the children.

Results

After three nights of receiving the eye mask intervention, the children in the experimental group had significantly lower sleep quality scores than those in the control group; the difference was statistically significant (p < 0.05), and the children in the experimental group had higher sleep quality. The experimental group's pain scores were significantly lower than the control group's, and the difference was statistically significant (p < 0.05), and the children in the experimental group experienced less post-operative pain.

Conclusions

Eye masks are a simple, safe and economical intervention, that is beneficial for improving the sleep quality and reducing pain in children over 5 years old with humeral supracondylar fracture after closed reduction and percutaneous pinning. It can be used as a reference and basis for clinical pain relief and sleep quality after surgery for supracondylar fractures of the humerus in children.

Extended Reality Use in Paediatric Intensive Care: A Scoping Review

Background: Extended reality (XR) technology such as virtual and augmented reality is increasingly being utilised in paediatric medicine due to its role in medical education and reported positive impacts on outcomes including pain, anxiety, and sleep. To the author's knowledge, no previous reviews investigating the use of XR in paediatric intensive care have been undertaken. Objectives: To scope the use of XR in paediatric intensive care, and assess its barriers to adoption, including safety considerations, cleaning and infection control. Eligibility criteria: All articles of any methodological design discussing the use of XR within paediatric intensive and critical care were included. Sources of evidence: Four databases (EMBASE, CINAHL, PsychInfo, PubMed) and Google Scholar were searched without any limitations on publication year. Charting methods: Data was extracted into Microsoft Excel by two authors independently (AG & SF) and cross-checked for completeness. Results: One hundred and eighty-eight articles were originally identified. Following the application of eligibility criteria 16 articles utilising XR in clinical interventions (n = 7) and medical education (n = 9) were included. Articles utilised VR and AR for highly variable purposes within both medical education (eg disaster preparedness, intubation) and clinical interventions (eg decrease pain, nausea, anxiety and improve Glasgow Coma Scale). Conclusions: While research into the use of XR in paediatric intensive care is still in its infancy it has increased dramatically over the past 5 years within two key areas. Firstly, in healthcare education, to assist in the acquisition of PICU-specific knowledge and practice of skills such as intubation of difficult airways. Secondly, studies have evaluated and demonstrated that with appropriate use, VR appears to be a safe and feasible intervention to decrease pain and anxiety in PICU patients.

A common neuronal ensemble in nucleus accumbens regulates pain-like behaviour and sleep

A comorbidity of chronic pain is sleep disturbance. Here, we identify a dual-functional ensemble that regulates both pain-like behaviour induced by chronic constrictive injury or complete Freund's adjuvant, and sleep wakefulness, in the nucleus accumbens (NAc) in mice. Specifically, a select population of NAc neurons exhibits increased activity either upon nociceptive stimulation or during wakefulness. Experimental activation of the ensemble neurons exacerbates pain-like (nociceptive) responses and reduces NREM sleep, while inactivation of these neurons produces the opposite effects. Furthermore, NAc ensemble primarily consists of D1 neurons and projects divergently to the ventral tegmental area (VTA) and preoptic area (POA). Silencing an ensemble innervating VTA neurons selectively increases nociceptive responses without affecting sleep, whereas inhibiting ensemble-innervating POA neurons decreases NREM sleep without affecting nociception. These results suggest a common NAc ensemble that encodes chronic pain and controls sleep, and achieves the modality specificity through its divergent downstream circuit targets.

The Underlying Mechanisms of Sleep Deprivation Exacerbating Neuropathic Pain

Pain disrupts sleep, and sleep deprivation or interference can alter pain perception in animals and humans, for example by increasing sensitivity to pain. However, the mechanism by which sleep affects neuropathic pain remains unclear. In this review, we discuss the available evidence from the epidemiologic, clinical, and human, as well as laboratory studies. In previous studies, we have found that sleep deprivation affects various injurious systems, including opioids, dopaminergic, immune, orexins, hypothalamic-pituitary-adrenal axis, and adenosine. At the same time, these systems play a crucial role in neuropathic pain regulation. In the complex interactions between these neurobiological systems, there may be potential regulatory pathways through which sleep deprivation amplifies neuropathic pain. Because of the impact sleep problems and neuropathic pain can have on the patients' quality of life, studying the link between sleep and neuropathic pain is important for neuropathic pain prevention and public health.

Brain-predicted age difference mediates the association between PROMIS sleep impairment, and self-reported pain measure in persons with knee pain

Knee pain, the most common cause of musculoskeletal pain (MSK), constitutes a severe public health burden. Its neurobiological causes, however, remain poorly understood. Among many possible causes, it has been proposed that sleep problems could lead to an increase in chronic pain symptomatology, which may be driven by central nervous system changes. In fact, we previously found that brain cortical thickness mediated the relationship between sleep qualities and pain severity in older adults with MSK. We also demonstrated a significant difference in a machine-learning-derived brain-aging biomarker between participants with low-and high-impact knee pain. Considering this, we examined whether brain aging was associated with self-reported sleep and pain measures, and whether brain aging mediated the relationship between sleep problems and knee pain. Exploratory Spearman and Pearson partial correlations, controlling for age, sex, race and study site, showed a significant association of brain aging with sleep related impairment and self-reported pain measures. Moreover, mediation analysis showed that brain aging significantly mediated the effect of sleep related impairment on clinical pain and physical symptoms. Our findings extend our prior work demonstrating advanced brain aging among individuals with chronic pain and the mediating role of brain-aging on the association between sleep and pain severity. Future longitudinal studies are needed to further understand whether the brain can be a therapeutic target to reverse the possible effect of sleep problems on chronic pain.

Pain in Huntington's disease and its potential mechanisms

Pain is common and frequent in many neurodegenerative diseases, although it has not received much attention. In Huntington's disease (HD), pain is often ignored and under-researched because attention is more focused on motor and cognitive decline than psychiatric symptoms. In HD progression, pain symptoms are complex and involved in multiple etiologies, particularly mental issues such as apathy, anxiety and irritability. Because of psychiatric issues, HD patients rarely complain of pain, although their bodies show severe pain symptoms, ultimately resulting in insufficient awareness and lack of research. In HD, few studies have focused on pain and pain-related features. A detailed and systemic pain history is crucial to assess and explore pain pathophysiology in HD. This review provides an overview concentrating on pain-related factors in HD, including neuropathology, frequency, features, affecting factors and mechanisms. More attention and studies are still needed in this interesting field in the future.

Role of astrocytes in sleep deprivation: accomplices, resisters, or bystanders?

Sleep plays an essential role in all studied animals with a nervous system. However, sleep deprivation leads to various pathological changes and neurobehavioral problems. Astrocytes are the most abundant cells in the brain and are involved in various important functions, including neurotransmitter and ion homeostasis, synaptic and neuronal modulation, and blood-brain barrier maintenance; furthermore, they are associated with numerous neurodegenerative diseases, pain, and mood disorders. Moreover, astrocytes are increasingly being recognized as vital contributors to the regulation of sleep-wake cycles, both locally and in specific neural circuits. In this review, we begin by describing the role of astrocytes in regulating sleep and circadian rhythms, focusing on: (i) neuronal activity; (ii) metabolism; (iii) the glymphatic system; (iv) neuroinflammation; and (v) astrocyte-microglia cross-talk. Moreover, we review the role of astrocytes in sleep deprivation comorbidities and sleep deprivation-related brain disorders. Finally, we discuss potential interventions targeting astrocytes to prevent or treat sleep deprivation-related brain disorders. Pursuing these questions would pave the way for a deeper understanding of the cellular and neural mechanisms underlying sleep deprivation-comorbid brain disorders.

Lagged effect of Patient-Reported Outcomes Measurement Information System (PROMIS) Sleep Disturbance on subacute postsurgical PROMIS Pain Behavior

Sleep disturbance is a modifiable risk factor that, when reduced, may improve subacute postsurgical outcomes (e.g., pain-related impact). Evidence also indicates that pain and sleep may have a bidirectional longitudinal relationship before to (sub) acutely after surgery. The objective of the present study is to examine the degree to which sleep disturbances and pain behavior have uni- or bidirectional relationships in a sample of patients undergoing sports orthopedic surgery. In this observational, longitudinal cohort study, participants ( = 296) were adult (ages 18+) active duty service members who underwent open or arthroscopic shoulder or knee surgery at Walter Reed National Military Medical Center. Participants were asked to complete PROMIS Sleep Disturbance and Pain Behavior computer adaptive testing item banks before surgery, 6 weeks postsurgery, and 3 months postsurgery. Patient-level covariates were analyzed for interrelationships using nonparametric bivariate statistics. Autoregressive and cross-lagged structural equation modeling examined the bidirectional relationships of patient-level covariates and PROMIS outcomes. When controlling for patient-level covariates, sleep disturbance at presurgical and 2-week postsurgical timepoints were positively associated with both sleep disturbance and pain behavior at the subsequent timepoint. Sleep disturbance may contribute to pain-related functioning and quality of life after sports orthopedic surgery. Future studies utilizing multidimensional patient report outcomes and robust analytics are needed to better understand whether sleep-targeted interventions can improve subacute and long-term orthopedic sports surgery outcomes.

Associations between resting state brain activity and A1 adenosine receptor availability in the healthy brain: Effects of acute sleep deprivation

Introduction

Previous resting-state fMRI (Rs-fMRI) and positron emission tomography (PET) studies have shown that sleep deprivation (SD) affects both spontaneous brain activity and A1 adenosine receptor (A1AR) availability. Nevertheless, the hypothesis that the neuromodulatory adenosinergic system acts as regulator of the individual neuronal activity remains unexplored.

Methods

Therefore, fourteen young men underwent Rs-fMRI, A1AR PET scans, and neuropsychological tests after 52 h of SD and after 14 h of recovery sleep.

Results

Our findings suggested higher oscillations or regional homogeneity in multiple temporal and visual cortices, whereas decreased oscillations in cerebellum after sleep loss. At the same time, we found that connectivity strengths increased in sensorimotor areas and decreased in subcortical areas and cerebellum.

Discussion

Moreover, negative correlations between A1AR availability and rs-fMRI metrics of BOLD activity in the left superior/middle temporal gyrus and left postcentral gyrus of the human brain provide new insights into the molecular basis of neuronal responses induced by high homeostatic sleep pressure.

Pain interferes with daily activities, emotions and sleep in adults with severe, moderate and mild haemophilia: A national cross-sectional survey

INTRODUCTION

Pain is a major issue in people with haemophilia (PwH). Few studies comprehensively assessed pain in PwH using a biopsychosocial framework and studies in mild PwH are lacking.

AIM

To assess pain prevalence, pain interference and their relationship with health-related quality of life (HR-QoL) in male adults with haemophilia.

METHODS

A survey was initiated by the Belgian national member organisation. Pain in the last 24 h, pain severity (BPI-PS) and pain interference (BPI-PI) scores were obtained with the Brief Pain Inventory short-form (BPI). HR-QoL was evaluated with the EQ-5D-3L, giving the health utility index (EQ-HUI). Associations between EQ-HUI, BPI-PS and BPI-PI were analysed using Pearson's correlation test. A multiple regression analysed the relationship between HR-QoL and BPI-PS, with age and haemophilia severity as confounding factors.

RESULTS

Within 185 respondents (97, 31 and 57 respectively severe, moderate and mild PwH), 67% (118/177) reported pain. In severe, moderate and mild PwH, respectively 86% (79/92), 71% (22/31) and 32% (17/54) reported pain. Median [IQR] BPI-PS, BPI-PI and EQ-HUI scores were respectively 1.5 [.0; 4.0], 1.6 [.0; 3.6] and .81 [.69; 1.00]. PwH reported pain interference with general activity (56% (99/176)), psychosocial factors such as mood (53% (93/175)), and sleep (51% (90/177)). Moderate correlations were found between EQ-HUI, BPI-PS and BPI-PI. After adjusting for age and haemophilia severity, BPI-PS explained 14% of HR-QoL variance.

CONCLUSIONS

Pain is a major issue amongst PwH, including people with mild haemophilia. Pain interferes with activities, emotions, sleep and HR-QoL, arguing for a comprehensive biopsychosocial approach of pain.

Chronic pain recruits hypothalamic dynorphin/kappa opioid receptor signalling to promote wakefulness and vigilance

Increased vigilance in settings of potential threats or in states of vulnerability related to pain is important for survival. Pain disrupts sleep and conversely, sleep disruption enhances pain, but the underlying mechanisms remain unknown. Chronic pain engages brain stress circuits and increases secretion of dynorphin, an endogenous ligand of the kappa opioid receptor (KOR). We therefore hypothesized that hypothalamic dynorphin/KOR signalling may be a previously unknown mechanism that is recruited in pathological conditions requiring increased vigilance. We investigated the role of KOR in wakefulness, non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep in freely moving naïve mice and in mice with neuropathic pain induced by partial sciatic nerve ligation using EEG/EMG recordings. Systemic continuous administration of U69,593, a KOR agonist, over 5 days through an osmotic minipump decreased the amount of NREM and REM sleep and increased sleep fragmentation in naïve mice throughout the light-dark sleep cycle. We used KORcre mice to selectively express a Gi-coupled designer receptor activated by designer drugs (Gi-DREADD) in KORcre neurons of the hypothalamic paraventricular nucleus, a key node of the hypothalamic-pituitary-adrenal stress response. Sustained activation of Gi-DREADD with clozapine-N-oxide delivered in drinking water over 4 days, disrupted sleep in these mice in a similar way as systemic U69,593. Mice with chronic neuropathic pain also showed disrupted NREM and total sleep that was normalized by systemic administration of two structurally different KOR antagonists, norbinaltorphimine and NMRA-140, currently in phase II clinical development, or by CRISPR/Cas9 editing of paraventricular nucleus KOR, consistent with endogenous KOR activation disrupting sleep in chronic pain. Unexpectedly, REM sleep was diminished by either systemic KOR antagonist or by CRISPR/Cas9 editing of paraventricular nucleus KOR in sham-operated mice. Our findings reveal previously unknown physiological and pathophysiological roles of dynorphin/KOR in eliciting arousal. Physiologically, dynorphin/KOR signalling affects transitions between sleep stages that promote REM sleep. Furthermore, while KOR antagonists do not promote somnolence in the absence of pain, they normalized disrupted sleep in chronic pain, revealing a pathophysiological role of KOR signalling that is selectively recruited to promote vigilance, increasing chances of survival. Notably, while this mechanism is likely beneficial in the short-term, disruption of the homeostatic need for sleep over longer periods may become maladaptive resulting in sustained pain chronicity. A novel approach for treatment of chronic pain may thus result from normalization of chronic pain-related sleep disruption by KOR antagonism.

Sleep staging in the ICU with heart rate variability and breathing signals. An exploratory cross-sectional study using deep neural networks

Introduction: To measure sleep in the intensive care unit (ICU), full polysomnography is impractical, while activity monitoring and subjective assessments are severely confounded. However, sleep is an intensely networked state, and reflected in numerous signals. Here, we explore the feasibility of estimating conventional sleep indices in the ICU with heart rate variability (HRV) and respiration signals using artificial intelligence methods Methods: We used deep learning models to stage sleep with HRV (through electrocardiogram) and respiratory effort (through a wearable belt) signals in critically ill adult patients admitted to surgical and medical ICUs, and in age and sex-matched sleep laboratory patients Results: We studied 102 adult patients in the ICU across multiple days and nights, and 220 patients in a clinical sleep laboratory. We found that sleep stages predicted by HRV- and breathing-based models showed agreement in 60% of the ICU data and in 81% of the sleep laboratory data. In the ICU, deep NREM (N2 + N3) proportion of total sleep duration was reduced (ICU 39%, sleep laboratory 57%, p < 0.01), REM proportion showed heavy-tailed distribution, and the number of wake transitions per hour of sleep (median 3.6) was comparable to sleep laboratory patients with sleep-disordered breathing (median 3.9). Sleep in the ICU was also fragmented, with 38% of sleep occurring during daytime hours. Finally, patients in the ICU showed faster and less variable breathing patterns compared to sleep laboratory patients Conclusion: The cardiovascular and respiratory networks encode sleep state information, which, together with artificial intelligence methods, can be utilized to measure sleep state in the ICU.

Probing different paradigms of morphine withdrawal on sleep behavior in male and female C57BL/6J mice

Opioid misuse has dramatically increased over the last few decades resulting in many people suffering from opioid use disorder (OUD). The prevalence of opioid overdose has been driven by the development of new synthetic opioids, increased availability of prescription opioids, and more recently, the COVID-19 pandemic. Coinciding with increases in exposure to opioids, the United States has also observed increases in multiple Narcan (naloxone) administrations as life-saving measures for respiratory depression, and, thus, consequently, naloxone-precipitated withdrawal. Sleep dysregulation is a main symptom of OUD and opioid withdrawal syndrome, and therefore, should be a key facet of animal models of OUD. Here we examine the effect of precipitated and spontaneous morphine withdrawal on sleep behaviors in C57BL/6J mice. We find that morphine administration and withdrawal dysregulate sleep, but not equally across morphine exposure paradigms. Furthermore, many environmental triggers promote relapse to drug-seeking/taking behavior, and the stress of disrupted sleep may fall into that category. We find that sleep deprivation dysregulates sleep in mice that had previous opioid withdrawal experience. Our data suggest that the 3-day precipitated withdrawal paradigm has the most profound effects on opioid-induced sleep dysregulation and further validates the construct of this model for opioid dependence and OUD.

Highlights

Morphine withdrawal differentially dysregulates the sleep of male and female mice3-day precipitated withdrawal results in larger changes than spontaneous withdrawalOpioid withdrawal affects responses to future sleep deprivation differently between sexes.

Pathological Cycle between Pain, Insomnia, and Anxiety in Women with Fibromyalgia and its Association with Disease Impact

BACKGROUND

Pain, sleep disturbances, and mood disorders are considered common symptoms of fibromyalgia (FM). However, the interactions that are established between them and the implication that this has in the disease are not clear. The main objective of this study is to clarify the relationships established between insomnia, pain intensity and anxiety in women with FM. Additionally, the effect that the indicated pathological cycle between pain, insomnia and anxiety may have on the impact of the disease in these patients is explored.

METHODS

A total of 228 women diagnosed with FM participated in this study (mean age = 56.99 years, SD = 10.35). Measurements were conducted at two time points. Initially, the women completed self-report questionnaires about anxiety (The Hospital Anxiety and Depression Scale; HADS), sleep problems (The Insomnia Severity Index; ISI) and pain intensity (Brief Pain Inventory; BPI), and a week later, they answered questions about the impact of fibromyalgia (Fibromyalgia Impact Questionnaire- Revised; FIQ-R). For data analysis, models 4 and 6 of the Macro Process for SPSS were used.

RESULTS

Insomnia predicts higher levels of pain, which in turn predicts higher levels of anxiety, which in turn predicts a higher impact of fibromyalgia (B = 2.76, SE = 1.10, 95% CI = [0.79,5.11]). No significant results were found for the other interactions between the variables.

CONCLUSIONS

Due to the clinical and scientific relevance of the insomnia-pain-anxiety pathological cycle and given the impact it has on FM, it is especially relevant to develop programs for patients with fibromyalgia based mainly on improving sleep quality.

Dehydrocorydaline alleviates sleep deprivation-induced persistent postoperative pain in adolescent mice through inhibiting microglial P2Y12 receptor expression in the spinal cord

During adolescence, a second period of central nervous system (CNS) plasticity that follows the fetal period, which involves sleep deprivation (SD), becomes apparent. SD during adolescence may result in abnormal development of neural circuits, causing imbalance in neuronal excitation and inhibition, which not only results in pain, but increases the chances of developing emotion disorders in adulthood, such as anxiety and depression. The quantity of surgeries during adolescence is also consistently on the rise, yet the impact and underlying mechanism of preoperative SD on postoperative pain remain unexplored. This study demonstrates that preoperative SD induces upregulation of the P2Y12 receptor, which is exclusively expressed on spinal microglia, and phosphorylation of its downstream signaling pathway p38Mitogen-activated protein/Nuclear transcription factor-κB (p38MAPK/NF-κB)in spinal microglia, thereby promoting microglia activation and microglial transformation into the proinflammatory M1 phenotype, resulting in increased expression of proinflammatory cytokines that exacerbate persisting postoperative incisional pain in adolescent mice. Both intrathecal minocycline (a microglia activation inhibitor) and MRS2395 (a P2Y12 receptor blocker) effectively suppressed microglial activation and proinflammatory cytokine expression. Interestingly, supplementation with dehydrocorydaline (DHC), an extract of Rhizoma Corydalis, inhibited the P2Y12/p38MAPK/NF-κB signaling pathway, microglia activation, and expression of pro-inflammatory cytokines in the model mice. Taken together, the results indicate that the P2Y12 receptor and microglial activation are important factors in persistent postoperative pain caused by preoperative SD in adolescent mice and that DHC has analgesic effects by acting on these targets.

Analgesic efficacy of sleep-promoting pharmacotherapy in patients with chronic pain: a systematic review and meta-analysis

Dysregulation of sleep heightens pain sensitivity and may contribute to pain chronification. Interventions which consolidate and lengthen sleep have the potential to improve pain control. The main objective of this systematic review was to examine the effects of sleep-promoting pharmacotherapy on pain intensity in patients with chronic pain. Multiple electronic databases were searched from inception to January 2022 to identify relevant randomized controlled trials (RCTs). Two independent reviewers screened titles, abstracts, and full-text articles; extracted data; and assessed risk of bias for each included study. The GRADE approach was used to determine the strength of evidence. The search identified 624 articles. After full-text screening, 10 RCTs (n = 574 randomized participants) involving 3 pharmacologic interventions (melatonin, zopiclone, and eszopiclone) and 7 different chronic pain populations were included. Minimum clinically significant pain reduction ≥30% was reported in 4 studies. There is low-quality evidence (downgraded due to inconsistency and imprecision) that 2 to 8 weeks treatment with a sleep-promoting medication alone or in combination with an analgesic (6 trials, n = 397) decreases pain intensity compared with placebo or the same analgesic treatment alone (SMD -0.58 [95% confidence interval -1.00, -0.17], P = 0.006). Analyses of associations between changes in sleep and pain outcomes were only provided in 2 articles, with inconsistent findings. Notably, pain-relieving effects were most consistent in melatonin trials. Only 3 studies implemented polysomnography to obtain objective sleep measures. Low-quality evidence indicates that pharmacologic sleep promotion may decrease pain intensity in chronic pain populations. More research is needed to fully understand the influence of sleep-targeting interventions on pain control.

Reciprocal relationships between sleep and smell

Despite major anatomical differences with other mammalian sensory systems, olfaction shares with those systems a modulation by sleep/wake states. Sleep modulates odor sensitivity and serves as an important regulator of both perceptual and associative odor memory. In addition, however, olfaction also has an important modulatory impact on sleep. Odors can affect the latency to sleep onset, as well as the quality and duration of sleep. Olfactory modulation of sleep may be mediated by direct synaptic interaction between the olfactory system and sleep control nuclei, and/or indirectly through odor modulation of arousal and respiration. This reciprocal interaction between sleep and olfaction presents novel opportunities for sleep related modulation of memory and perception, as well as development of non-pharmacological olfactory treatments of simple sleep disorders.

Effect of sleep loss on pain-New conceptual and mechanistic avenues

Introduction

Sleep disturbances increase pain sensitivity in clinical and preclinical settings, but the precise mechanisms are unknown. This represents a major public health issue because of the growing sleep deficiency epidemic fueled by modern lifestyle. To understand the neural pathways at the intersection between sleep and pain processes, it is critical to determine the precise nature of the sleep disruptions that increase pain and the specific component of the pain response that is targeted.

Methods

We performed a review of the literature about sleep disturbances and pain sensitivity in humans and rodents by taking into consideration the targeted sleep stage (REMS, non-NREMS, or both), the amount of sleep lost, and the different types of sleep disruptions (partial or total sleep loss, duration, sleep fragmentation or interruptions), and how these differences might affect distinct components of the pain response.

Results

We find that the effects of sleep disturbances on pain are highly conserved among species. The major driver for pain hypersensitivity appears to be the total amount of sleep lost, while REMS loss by itself does not seem to have a direct effect on pain sensitivity. Sleep loss caused by extended wakefulness preferentially increases pain perception, whereas interrupted and limited sleep strongly dysregulates descending controls such as DNIC, especially in women.

Discussion

We discuss the possible mechanisms involved, including an increase in inflammatory processes, a loss of nociceptive inhibitory pathways, and a defect in the cognitive processing of noxious input.

Preoperative Acute Sleep Deprivation Causes Postoperative Pain Hypersensitivity and Abnormal Cerebral Function

Preoperative sleep loss can amplify post-operative mechanical hyperalgesia. However, the underlying mechanisms are still largely unknown. In the current study, rats were randomly allocated to a control group and an acute sleep deprivation (ASD) group which experienced 6 h ASD before surgery. Then the variations in cerebral function and activity were investigated with multi-modal techniques, such as nuclear magnetic resonance, functional magnetic resonance imaging, c-Fos immunofluorescence, and electrophysiology. The results indicated that ASD induced hyperalgesia, and the metabolic kinetics were remarkably decreased in the striatum and midbrain. The functional connectivity (FC) between the nucleus accumbens (NAc, a subregion of the ventral striatum) and the ventrolateral periaqueductal gray (vLPAG) was significantly reduced, and the c-Fos expression in the NAc and the vLPAG was suppressed. Furthermore, the electrophysiological recordings demonstrated that both the neuronal activity in the NAc and the vLPAG, and the coherence of the NAc-vLPAG were suppressed in both resting and task states. This study showed that neuronal activity in the NAc and the vLPAG were weakened and the FC between the NAc and the vLPAG was also suppressed in rats with ASD-induced hyperalgesia. This study highlights the importance of preoperative sleep management for surgical patients.

The effects of eye masks on post-operative sleep quality and pain in school-age children with CHD

OBJECTIVE

This study aimed to explore the effects of eye masks on the sleep quality and pain of school-age children with CHD after surgery.

METHODS

Forty school-age children with CHD who underwent open-heart surgery in the Cardiac Surgery Department of a provincial hospital in China from January 2020 to December 2020 were selected. The children were randomly divided into the experimental group (n = 20) and the control group (n = 20). Children in the control group were given routine sleep care, and the children in the experimental group were given a sleep intervention with eye masks for three nights following the removal of tracheal intubation. The Pittsburgh Sleep Quality Index was used to evaluate the sleep quality of the children. The Children's Pain Behaviour Scale was used to evaluate the pain of the children.

RESULTS

After three nights of receiving the eye masks intervention, the sleep quality scores of the children in the experimental group were significantly lower than those of the control group, the difference was statistically significant (p < 0.05) and the sleep quality of the children in the experimental group was higher. The pain scores of the children in the experimental group were significantly lower than those of the children in the control group, the difference was statistically significant (p < 0.05), and the children in the experimental group suffered less post-operative pain.

CONCLUSION

Eye masks are a simple, safe and economical intervention, that is beneficial for improving the post-operative sleep quality and relieving post-operative pain in school-age children with congenital heart disease.

Underlying Music Mechanisms Influencing the Neurology of Pain: An Integrative Model

Pain is often debilitating, and is associated with many pathologies, as either a cause or consequence. Pharmacological interventions, such as opioids, to manage pain may lead to potential problems, such as addiction. When pain is controlled and managed, it can prevent negative associated outcomes affiliated with disease. Music is a low-cost option that shows promise in the management of painful circumstances. Music therapy has provided potent options for pain relief across a variety of ages and populations. As a nonpharmacological alternative or complement lacking side effects, music interventions are growing in clinical application and research protocols. This article considers the neurological implications of varying kinds of pain to provide working considerations that preempt the use of music and music-therapy applications in treating pain.

Modulation of melatonin to the thalamic lesion-induced pain and comorbid sleep disturbance in the animal model of the central post-stroke hemorrhage

The devastating chronic central post stroke pain is associated with variety of comorbidities. Disrupted sleep is a severe comorbidity, causing an increase in the suicide rate, due to CPSP’s pain symptom. Melatonin is a well-known jet-lag compound, which helps in entrainment of sleep cycle. Accordingly, whether melatonin as a therapeutic measurement for the regulation of sleep disturbance related to central post stroke pain remains unclear. Exogenous melatonin administration entrained the disrupted 24 h circadian cycle, more effectively after 2 and 3 week of administration. The effect of melatonin was persisted on 4th week too, when melatonin administration was discontinued. Also, melatonin ameliorated the pain due to distorted sleep-activity behavior after melatonin administration for 3 weeks. The low levels of melatonin in blood plasma due to CPSP were restored after 3 weeks of melatonin administration. After 30 mg/kg melatonin administrations for 3 weeks, all the disrupted resting and activity behaviors were reduced during light and dark periods. The results suggested that melatonin significantly ameliorated CPSP’s pain symptoms and comorbid sleep disturbance showing in activity behavior.

A scoping review on the effect of cannabis on pain intensity in people with spinal cord injury

CONTEXT

This scoping review examines the current research on the effect of cannabis upon pain intensity in spinal cord injury (SCI) pain. Chronic pain is a significant secondary condition following SCI, and traditional treatments (e.g. opioids, NSAIDs) are often criticized for providing inadequate relief. As a result, there is increasing interest in and use of cannabis and cannabinoid-based medications as an alternative means of pain control.

OBJECTIVE

The purpose of this review was to examine the scientific evidence on the effect of cannabis/cannabinoids upon pain intensity in SCI by mapping the current literature.

METHODS

Two hundred and fifty-two studies were identified by searching electronic databases for articles published through February 2020. In addition, reviewers scanned the reference lists of identified articles and examined clinicaltrials.gov for unpublished data in this area. Title, abstract, and full-text reviews were completed by two independent reviewers. Data extraction was performed by a single reviewer and verified by a second reviewer.

RESULTS

Six articles covering five treatment studies were included. Studies yielded mixed findings likely due to large variability in methodology, including lack of standardized dosing paradigms, modes of use, and duration of trial.

CONCLUSIONS

The current quality and level of evidence is insufficient to draw reliable conclusions of the efficacy of cannabis upon SCI-related pain itensity. We identify specific limitations of past studies and present guidelines for future research.Trial registration: ClinicalTrials.gov identifier: Nct01606202..

The Role of Inflammation, Hypoxia, and Opioid Receptor Expression in Pain Modulation in Patients Suffering from Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a relatively common disease in the general population. Besides its interaction with many comorbidities, it can also interact with potentially painful conditions and modulate its course. The association between OSA and pain modulation has recently been a topic of concern for many scientists. The mechanism underlying OSA-related pain connection has been linked with different pathophysiological changes in OSA and various pain mechanisms. Furthermore, it may cause both chronic and acute pain aggravation as well as potentially influencing the antinociceptive mechanism. Characteristic changes in OSA such as nocturnal hypoxemia, sleep fragmentation, and systemic inflammation are considered to have a curtailing impact on pain perception. Hypoxemia in OSA has been proven to have a significant impact on increased expression of proinflammatory cytokines influencing the hyperalgesic priming of nociceptors. Moreover, hypoxia markers by themselves are hypothesized to modulate intracellular signal transduction in neurons and have an impact on nociceptive sensitization. Pain management in patients with OSA may create problems arousing from alterations in neuropeptide systems and overexpression of opioid receptors in hypoxia conditions, leading to intensification of side effects, e.g., respiratory depression and increased opioid sensitivity for analgesic effects. In this paper, we summarize the current knowledge regarding pain and pain treatment in OSA with a focus on molecular mechanisms leading to nociceptive modulation.

Effect of percutaneous electrical nerve field stimulation on mechanosensitivity, sleep, and psychological comorbidities in adolescents with functional abdominal pain disorders

BACKGROUND

Percutaneous electrical nerve field stimulation (PENFS) improves symptoms in adolescents with functional abdominal pain disorders (FAPDs). However, little is known about its impact on sleep and psychological functioning. We evaluated the effects of PENFS on resting and evoked pain and nausea, sleep and psychological functioning, and long-term outcomes.

METHODS

Patient ages 11-19 years with FAPD requiring PENFS as standard care were recruited. Evoked pain was elicited by a Water Load Symptom Provocation Task (WL-SPT) before and after four weeks of treatment. Pain, gastrointestinal symptoms, sleep, somatic symptoms, and physical and psychological functioning were assessed. Actigraphy was used to measure daily sleep-wake patterns.

KEY RESULTS

Twenty patients (14.3 ± 2.2 years old) with FAPD were enrolled. Most patients were females (70%) and white (95%). During pain evoked by WL-SPT, visual analog scale (VAS) pain intensity and nausea were lower following PENFS compared with baseline (p = 0.004 and p = 0.02, respectively). After PENFS, resting VAS pain unpleasantness (p = 0.03), abdominal pain (p < 0.0001), pain catastrophizing (p = 0.0004), somatic complaints (0.01), functional disability (p = 0.04), and anxiety (p = 0.02) exhibited significant improvements, and some were sustained long-term. Self-reported sleep improved after PENFS (p's < 0.05) as well as actigraphy-derived sleep onset latency (p = 0.03).

CONCLUSIONS AND INFERENCES

We demonstrated improvements in resting and evoked pain and nausea, sleep, disability, pain catastrophizing, somatic complaints, and anxiety after four weeks of PENFS therapy. Some effects were sustained at 6-12 months post-treatment. This suggests that PENFS is a suitable alternative to pharmacologic therapy.

Physicians prescribe fewer analgesics during night shifts than day shifts

Adequate pain management is one of the biggest challenges of the modern healthcare system. Physician perception of patient subjective pain, which is crucial to pain management, is susceptible to a host of potential biases. Here we explore the timing of physicians' work as a previously unrecognized source of systematic bias in pain management. We hypothesized that during night shifts, sleep deprivation, fatigue, and stress would reduce physicians' empathy for others' pain, leading to underprescription of analgesics for patient pain relief. In study 1, 67 resident physicians, either following a night shift or not, performed empathy for pain assessment tasks and simulated patient scenarios in laboratory conditions. As predicted, following a night shift, physicians showed reduced empathy for pain. In study 2, we explored this phenomenon in medical decisions in the field. We analyzed three emergency department datasets from Israel and the United States that included discharge notes of patients arriving with pain complaints during 2013 to 2020 (n = 13,482). Across all datasets, physicians were less likely to prescribe an analgesic during night shifts (compared to daytime shifts) and prescribed fewer analgesics than generally recommended by the World Health Organization. This effect remained significant after adjusting for patient, physician, type of complaint, and emergency department characteristics. Underprescription for pain during night shifts was particularly prominent for opioids. We conclude that night shift work is an important and previously unrecognized source of bias in pain management, likely stemming from impaired perception of pain. We consider the implications for hospitals and other organizations employing night shifts.

Bidirectional associations between chronic low back pain and sleep quality: A cohort study with schoolteachers

AIMS

Although both chronic low back pain (cLBP) and sleep problems are prevalent among active workers, the relation between these variables is not well established. This study aimed to examine the bidirectional association between cLBP and sleep in schoolteachers.

METHODS

The Pittsburgh Sleep Quality Index (PSQI) and cLBP were self-reported by 530 schoolteachers in Londrina, Brazil, at baseline and after 2 years of follow-up. Generalized estimating equations were adjusted for sociodemographic, lifestyle and mental health variables.

RESULTS

Poor sleep quality at baseline was associated with cLBP at follow-up after adjusting for sociodemographic and lifestyle variables (OR=1.61; 95% confidence interval [95% CI]=1.06, 2.47). Changes in the PSQI score over time were also associated with a higher likelihood of cLBP at follow-up (OR=1.13; 95% CI=1.07, 1.20 for each 1-point increase in the PSQI score), regardless of mental health condition. cLBP at baseline was associated with worse sleep quality at follow-up after adjusting for sociodemographic and lifestyle variables (OR=1.56; 95% CI=1.02, 2.37). The presence of cLBP also changed the PSQI score over time (ß coefficient=1.153; 95% CI=0.493, 1.814).

CONCLUSIONS

Worse sleep quality was prospectively and bidirectionally associated with cLBP. Concretely, changes in PSQI values after 2 years of follow-up increased the likelihood of reporting cLBP, and baseline cLBP was associated with sleep quality worsening (i.e., higher score in the PSQI). Mental health conditions such as self-rated health, depression and anxiety play a relevant confounding role in the bidirectional associations between sleep and chronic low back pain.

The Affective Dimension of Pain Appears to Be Determinant within a Pain-Insomnia-Anxiety Pathological Loop in Fibromyalgia: A Case-Control Study

Background: Fibromyalgia (FM) is a chronic pain disease characterized by multiple symptoms whose interactions and implications in the disease pathology are still unclear. This study aimed at investigating how pain, sleep, and mood disorders influence each other in FM, while discriminating between the sensory and affective pain dimensions. Methods: Sixteen female FM patients were evaluated regarding their pain, while they underwent—along with 11 healthy sex- and age-adjusted controls—assessment of mood and sleep disorders. Analysis of variance and correlations were performed in order to assess group differences and investigate the interactions between pain, mood, and sleep descriptors. Results: FM patients reported the typical widespread pain, with similar sensory and affective inputs. Contrary to controls, they displayed moderate anxiety, depression, and insomnia. Affective pain (but neither the sensory pain nor pain intensity) was the only pain indicator that tendentially correlated with anxiety and insomnia, which were mutually associated. An affective pain–insomnia–anxiety loop was thus completed. High ongoing pain strengthened this vicious circle, to which it included depression and sensory pain. Conclusions: Discriminating between the sensory and affective pain components in FM patients disclosed a pathological loop, with a key role of affective pain; high ongoing pain acted as an amplifier of symptoms interaction. This unraveled the interplay between three of most cardinal FM symptoms; these results contribute to better understand FM determinants and pathology and could help in orienting therapeutic strategies.