Showing papers in "Nature and Science of Sleep in 2021"

Burden of Sleep Disturbance During COVID-19 Pandemic: A Systematic Review

Abstract: Coronavirus disease 2019 (COVID-19) pandemic may exert adverse impacts on sleep among populations, which may raise awareness of the burden of sleep disturbance, and the demand of intervention strategies for different populations. We aimed to summarize the current evidence for the impacts of COVID-19 on sleep in patients with COVID-19, healthcare workers (HWs), and the general population. We searched PubMed and Embase for studies on the prevalence of sleep disturbance. Totally, 86 studies were included in the review, including 16 studies for COVID-19 patients, 34 studies for HWs, and 36 studies for the general population. The prevalence of sleep disturbance was 33.3%-84.7%, and 29.5-40% in hospitalized COVID-19 patients and discharged COVID-19 survivors, respectively. Physiologic and psychological traumatic effects of the infection may interact with environmental factors to increase the risk of sleep disturbance in COVID-19 patients. The prevalence of sleep disturbance was 18.4-84.7% in HWs, and the contributors mainly included high workloads and shift work, occupation-related factors, and psychological factors. The prevalence of sleep disturbance was 17.65-81% in the general population. Physiologic and social-psychological factors contributed to sleep disturbance of the general population during COVID-19 pandemic. In summary, the sleep disturbance was highly prevalent during COVID-19 pandemic. Specific health strategies should be implemented to tackle sleep disturbance.

To Nap or Not to Nap? A Systematic Review Evaluating Napping Behavior in Athletes and the Impact on Various Measures of Athletic Performance.

Abstract: Purpose: The objective of this systematic review was to 1) determine how studies evaluated napping behavior in athletes (frequency, duration, timing and measurement); 2) explore how napping impacted physical performance, cognitive performance, perceptual measures (eg, fatigue, muscle soreness, sleepiness and alertness), psychological state and night-time sleep in athletes. Methods: Five bibliographic databases were searched from database inception to 11 August 2020. Observational and experimental studies comprising able-bodied athletes (mean age ≥ 12 years), published in English, in peer-reviewed journal papers were included. The Downs and Black Quality Assessment Checklist was used for quality appraisal. Results: Thirty-seven studies were identified of moderate quality. Most studies did not include consistent information regarding nap frequency, duration, and timing. Napping may be beneficial for a range of outcomes that benefit athletes (eg, physical and cognitive performance, perceptual measures, psychological state and night-time sleep). In addition, napping presents athletes with the opportunity to supplement their night-time sleep without compromising sleep quality. Conclusion: Athletes may consider napping between 20 to 90 min in duration and between 13:00 and 16:00 hours. Finally, athletes should allow 30 min to reduce sleep inertia prior to training or competition to obtain better performance outcomes. Future studies should include comprehensive recordings of nap duration and quality, and consider using sleep over a 24 hour period (daytime naps and night-time sleep period), specifically using objective methods of sleep assessment (eg, polysomnography/actigraphy).

How our Dreams Changed During the COVID-19 Pandemic: Effects and Correlates of Dream Recall Frequency - a Multinational Study on 19,355 Adults.

Abstract: Objective: Many have reported odd dreams during the pandemic. Given that dreams are associated with mental health, understanding these changes could provide crucial information about wellbeing during the pandemic. This study explored associations between COVID-19 and dream recall frequency (DRF), and related social, health, and mental health factors. Methods: We conducted a cross-sectional web survey of 19,355 individuals in 14 countries from May to July 2020. We collected data on COVID-19, mental health, sleep and DRF during the pandemic. We performed McNemar Tests to compare low (<3 nights per week) and high DRF (≥3 nights per week) before and during COVID-19 and to evaluate changes in sleep variables segmented by DRF. Chi-square tests were conducted to compare characteristics between low and high DRF. Logistic regression analyses were conducted to examine associations between various independent variables and DRF. Results: Reports of high DRF during the pandemic were higher than before the pandemic (P<0.001). Female gender (aOR=1.25, 95% CI 1.10-1.41), nightmares (aOR=4.22, 95% CI 3.45-5.17), sleep talking (aOR= 2.36, 1.73-3.23), sleep maintenance problems (aOR=1.34, 95% CI 1.15-1.56), symptoms of REM sleep behavior disorder (RBD; aOR=1.24, 95% CI 1.09-1.41) and repeated disturbing thoughts (posttraumatic stress disorder (PTSD) symptoms) were associated with high DRF. Age group 55-64 years (aOR=0.69, 95% CI 0.58-0.83) reported less high DRF than younger participants. Unadjusted OR showed associations between depression, anxiety, and DRF; however, in adjusted regression depression (aOR= 0.71, 0.59-0.86) and anxiety (aOR=0.79, 95% CI 0.66-0.94) were negatively associated with high DRF. Conclusion and Relevance: DRF was higher than pre-pandemic levels across four continents. DRF was associated with gender and parasomnias like nightmares and RBD symptoms, sleep maintenance problems, PTSD symptoms and negatively associated with depression and anxiety. The results implicate that COVID-19 is reflected in our dreams as an expression of the emotional intensity of the pandemic.

Multi-Night Validation of a Sleep Tracking Ring in Adolescents Compared with a Research Actigraph and Polysomnography

Abstract: Background Wearable devices have tremendous potential for large-scale longitudinal measurement of sleep, but their accuracy needs to be validated. We compared the performance of the multisensor Oura ring (Oura Health Oy, Oulu, Finland) to polysomnography (PSG) and a research actigraph in healthy adolescents. Methods Fifty-three adolescents (28 females; aged 15-19 years) underwent overnight PSG monitoring while wearing both an Oura ring and Actiwatch 2 (Philips Respironics, USA). Measurements were made over multiple nights and across three levels of sleep opportunity (5 nights with either 6.5 or 8h, and 3 nights with 9h). Actiwatch data at two sensitivity settings were analyzed. Discrepancies in estimated sleep measures as well as sleep-wake, and sleep stage agreements were evaluated using Bland-Altman plots and epoch-by-epoch (EBE) analyses. Results Compared with PSG, Oura consistently underestimated TST by an average of 32.8 to 47.3 minutes (Ps < 0.001) across the different TIB conditions; Actiwatch 2 at its default setting underestimated TST by 25.8 to 33.9 minutes. Oura significantly overestimated WASO by an average of 30.7 to 46.3 minutes. It was comparable to Actiwatch 2 at default sensitivity in the 6.5, and 8h TIB conditions. Relative to PSG, Oura significantly underestimated REM sleep (12.8 to 19.5 minutes) and light sleep (51.1 to 81.2 minutes) but overestimated N3 by 31.5 to 46.8 minutes (Ps < 0.01). EBE analyses demonstrated excellent sleep-wake accuracies, specificities, and sensitivities - between 0.88 and 0.89 across all TIBs. Conclusion The Oura ring yielded comparable sleep measurement to research grade actigraphy at the latter's default settings. Sleep staging needs improvement. However, the device appears adequate for characterizing the effect of sleep duration manipulation on adolescent sleep macro-architecture.

Transvenous Phrenic Nerve Stimulation for Treatment of Central Sleep Apnea: Five-Year Safety and Efficacy Outcomes

Abstract: Background The remedē System Pivotal Trial was a prospective, multi-center, randomized trial demonstrating transvenous phrenic nerve stimulation (TPNS) therapy is safe and effectively treats central sleep apnea (CSA) and improves sleep architecture and daytime sleepiness. Subsequently, the remedē System was approved by FDA in 2017. As a condition of approval, the Post Approval Study (PAS) collected clinical evidence regarding long-term safety and effectiveness in adults with moderate to severe CSA through five years post implant. Methods Patients remaining in the Pivotal Trial at the time of FDA approval were invited to enroll in the PAS and consented to undergo sleep studies (scored by a central laboratory), complete the Epworth Sleepiness Scale (ESS) questionnaire to assess daytime sleepiness, and safety assessment. All subjects (treatment and former control group) receiving active therapy were pooled; data from both trials were combined for analysis. Results Fifty-three of the original 151 Pivotal Trial patients consented to participate in the PAS and 52 completed the 5-year visit. Following TPNS therapy, the apnea-hypopnea index (AHI), central-apnea index (CAI), arousal index, oxygen desaturation index, and sleep architecture showed sustained improvements. Comparing 5 years to baseline, AHI and CAI decreased significantly (AHI baseline median 46 events/hour vs 17 at 5 years; CAI baseline median 23 events/hour vs 1 at 5 years), though residual hypopneas were present. In parallel, the arousal index, oxygen desaturation index and sleep architecture improved. The ESS improved by a statistically significant median reduction of 3 points at 5 years. Serious adverse events related to implant procedure, device or delivered therapy were reported by 14% of patients which include 16 (9%) patients who underwent a pulse generator reposition or lead revision (primarily in the first year). None of the events caused long-term harm. No unanticipated adverse device effects or related deaths occurred through 5 years. Conclusion Long-term TPNS safely improves CSA, sleep architecture and daytime sleepiness through 5 years post implant. Clinical trial registration ClinicalTrials.gov Identifier: NCT01816776.

Understanding the Impact of the COVID-19 Pandemic, Lockdowns and Social Isolation on Sleep Quality.

Abstract: The uncertain, ever-changing and an ongoing nature of the COVID-19 pandemic means that it may take some time before we can fully appreciate the negative effect of the pandemic and lockdown on our sleep and mental health. It is increasingly recognised that in the aftermath of pandemic, several persistent sleep, neuropsychiatric and physical sequelae may continue long after the pandemic is over. A body of evidence to date also highlights a significant disparity in sleep and mental health difficulties in specific vulnerable groups in the community, with different temporal profiles and sleep issues that are reported. In this perspective, we argue for a possible mechanistic impact of the COVID-19 pandemic, with its imposed restrictions and social isolation on sleep quality. We similarly discuss some of the potential international differences, as well as similarities, behind reported idiosyncratic biological vulnerabilities that may have contributed to the genesis of sleep issues. Lastly, we propose some possible implementations and innovations that may be needed in restructuring of sleep disorders services in order to benefit recovering COVID-19 patients.

The Role of Perioperative Sleep Disturbance in Postoperative Neurocognitive Disorders.

Abstract: Postoperative neurocognitive disorder (PND) increases the length of hospital stay, mortality, and risk of long-term cognitive impairment. Perioperative sleep disturbance is prevalent and commonly ignored and may increase the risk of PND. However, the role of perioperative sleep disturbances in PND remains unclear. Nocturnal sleep plays an indispensable role in learning, memory, and maintenance of cerebral microenvironmental homeostasis. Hospitalized sleep disturbances also increase the incidence of postoperative delirium and cognitive dysfunction. This review summarizes the role of perioperative sleep disturbances in PND and elucidates the potential mechanisms underlying sleep-deprivation-mediated PND. Activated neuroinflammation and oxidative stress; impaired function of the blood-brain barrier and glymphatic pathway; decreased hippocampal brain-derived neurotrophic factor, adult neurogenesis, and sirtuin1 expression; and accumulated amyloid-beta proteins are associated with PND in individuals with perioperative sleep disorders. These findings suggest that the improvement of perioperative sleep might reduce the incidence of postoperative delirium and postoperative cognitive dysfunction. Future studies should further investigate the role of perioperative sleep disturbance in PND.

The Coronavirus Pandemic: A Possible Model of the Direct and Indirect Impact of the Pandemic on Sleep Quality in Italians

Abstract: Purpose This study aimed to assess the direct and indirect impact of COVID-19-related aspects on self-reported sleep quality, considering the moderator role of some psychological variables. Methods During the first weeks of the lockdown in Italy, 2286 respondents (1706 females and 580 males; age range: 18-74 years) completed an online survey that collected sociodemographic information and data related to the experience with the COVID-19 pandemic. Some questionnaires assessed sleep quality, psychological well-being, general psychopathology, Post-Traumatic Stress Disorders symptoms, and anxiety. The path analysis was adopted. Results The study confirms a direct effect of some aspects ascribable to the pandemic, with a mediator role of the psychological variables. Lower sleep quality was directly related to the days spent at home in confinement and the knowledge of people affected by the COVID-19. All the other aspects related to the COVID-19 pandemic influenced sleep quality through the mediator effect of psychological variables. Conclusion This study highlighted that the psychological condition of the population has been influenced by the COVID-19 pandemic and the government actions taken to contain it, but it has also played an important role in mediating the quality of sleep, creating a vicious circle on people's health. The results suggest that a health emergency must be accompanied by adequate social support programs to mitigate the fear of infection and promote adequate resilience to accept confinement and social distancing. Such measures would moderate psychological distress and improve sleep quality.

Does Sleep Selectively Strengthen Certain Memories Over Others Based on Emotion and Perceived Future Relevance

Abstract: Sleep has been found to have a beneficial effect on memory consolidation. It has furthermore frequently been suggested that sleep does not strengthen all memories equally. The first aim of this review paper was to examine whether sleep selectively strengthens emotional declarative memories more than neutral ones. We examined this first by reviewing the literature focusing on sleep/wake contrasts, and then the literature on whether any specific factors during sleep preferentially benefit emotional memories, with a special focus on the often-suggested claim that rapid eye movement sleep primarily consolidates emotional memories. A second aim was to examine if sleep preferentially benefits memories based on other cues of future relevance such as reward, test-expectancy or different instructions during encoding. Once again, we first focused on studies comparing sleep and wake groups, and then on studies examining the contributions of specific factors during sleep (for each future relevance paradigm, respectively). The review revealed that although some support exists that sleep is more beneficial for certain kinds of memories based on emotion or other cues of future relevance, the majority of studies does not support such an effect. Regarding specific factors during sleep, our review revealed that no sleep variable has reliably been found to be specifically associated with the consolidation of certain kinds of memories over others based on emotion or other cues of future relevance.

The Impact of Quarantine on Sleep Quality and Psychological Distress During the COVID-19 Pandemic

Abstract: Purpose: We investigated the impact of isolation on sleep quality and psychological distress during the COVID-19 pandemic in Saudi Arabia. Methods: An online survey was conducted on 353 (88 isolated and 265 not isolated) individuals from May to June 2020. Subjective sleep quality was determined using the Pittsburgh sleep quality index (PSQI), and psychological distress measured using the Kessler psychological distress scale (K10). Results: The mean age of the isolated group was 28.6 years versus 27.5 years for the non-isolated group, with male participants accounting for 37% in both groups. The mean PSQI score was 8.5+/-3.6 and 8.4+/-3.5 for the isolated and non-isolated groups, respectively (P= 0.92). The mean K-10 score was 27.6+/- 9.4 and 25.3+/- 9.5 for the isolated and non-isolated groups, respectively (P= 0.04). Poor sleep (PSQI >=6) was reported in 235 (66.6%) and psychological distress (K-10 >=20) in 244 (69.1%) participants. Isolation was not associated with poor sleep (OR: 0.73 (95% CI: 0.41-1.3), P=0.29), but was statistically significant with psychological distress (OR: 2.12 (95% CI: 1.10-4.08), P=0.03). Conclusion: Poor sleep and psychological distress symptoms were highly prevalent in our study population. Isolation may influence psychological distress but not sleep quality during the COVID-19 pandemic.

It is All in the Wrist: Wearable Sleep Staging in a Clinical Population versus Reference Polysomnography.

Abstract: Purpose: There is great interest in unobtrusive long-term sleep measurements using wearable devices based on reflective photoplethysmography (PPG). Unfortunately, consumer devices are not validated in patient populations and therefore not suitable for clinical use. Several sleep staging algorithms have been developed and validated based on ECG-signals. However, translation from these techniques to data derived by wearable PPG is not trivial, and requires the differences between sensing modalities to be integrated in the algorithm, or having the model trained directly with data obtained with the target sensor. Either way, validation of PPG-based sleep staging algorithms requires a large dataset containing both gold standard measurements and PPG-sensor in the applicable clinical population. Here, we take these important steps towards unobtrusive, long-term sleep monitoring. Methods: We developed and trained an algorithm based on wrist-worn PPG and accelerometry. The method was validated against reference polysomnography in an independent clinical population comprising 244 adults and 48 children (age: 3 to 82 years) with a wide variety of sleep disorders. Results: The classifier achieved substantial agreement on four-class sleep staging with an average Cohen’s kappa of 0.62 and accuracy of 76.4%. For children/adolescents, it achieved even higher agreement with an average kappa of 0.66 and accuracy of 77.9%. Performance was significantly higher in non-REM parasomnias (kappa = 0.69, accuracy = 80.1%) and significantly lower in REM parasomnias (kappa = 0.55, accuracy = 72.3%). A weak correlation was found between age and kappa (ρ = −0.30, p<0.001) and age and accuracy (ρ = −0.22, p<0.001). Conclusion: This study shows the feasibility of automatic wearable sleep staging in patients with a broad variety of sleep disorders and a wide age range. Results demonstrate the potential for ambulatory long-term monitoring of clinical populations, which may improve diagnosis, estimation of severity and follow up in both sleep medicine and research.

Social Jetlag Changes During the COVID-19 Pandemic as a Predictor of Insomnia - A Multi-National Survey Study

Abstract: Purpose: Lifestyle and work habits have been drastically altered by restrictions due to the COVID-19 pandemic. Whether the associated changes in sleep timing modulate the risk of suffering from symptoms of insomnia, the most prevalent sleep disorder, is however incompletely understood. Here, we evaluate the association between the early pandemic-associated change in 1) the magnitude of social jetlag (SJL) - ie, the difference between sleep timing on working vs free days - and 2) symptoms of insomnia. Patients and Methods: A total of 14,968 anonymous participants (mean age: 40 years; 64% females) responded to a standardized internet-based survey distributed across 14 countries. Using logistic multivariate regression, we examined the association between the degree of social jetlag and symptoms of insomnia, controlling for important confounders like social restriction extension, country specific COVID-19 severity and psychological distress, for example. Results: In response to the pandemic, participants reported later sleep timing, especially during workdays. Most participants (46%) exhibited a reduction in their SJL, whereas 20% increased it; and 34% reported no change in SJL. Notably, we found that both increased and decreased SJL, as a result of the COVID-19 pandemic, were associated with later sleep midpoint (indicating a later chronotype) as well as more recurrent and moderate-to-severe symptoms of insomnia (about 23-54% higher odds ratio than subjects with unchanged SJL). Primarily those with reduced SJL shifted their bedtimes to a later timepoint, compared with those without changes in SJL. Conclusion: Our findings offer important insights into how self-reported changes to the stability of sleep/wake timing, as reflected by changes in SJL, can be a critical marker of the risk of experiencing insomnia-related symptoms - even when individuals manage to reduce their social jetlag. These findings emphasize the clinical importance of analyzing sleep-wake regularity.

The Top End Sleepiness Scale (TESS): A New Tool to Assess Subjective Daytime Sleepiness Among Indigenous Australian Adults.

Abstract: Purpose To illustrate the utility of a newly developed culturally safe and clinically relevant subjective daytime sleepiness assessment tool "Top End Sleepiness Scale" (TESS) for use among Indigenous Australians. Patients and methods The TESS questionnaire consists of pictorial representations of 6 items representing daily activities that would induce daytime sleepiness specific for Indigenous Australians living in the regional and remote Australia. Consecutive adult Indigenous patients who consented to pilot the TESS questionnaire prior to undergoing a diagnostic polysomnography (PSG) at the Top End Health Service region, Northern Territory of Australia were assessed. The TESS questionnaire was evaluated for its correlation in predicting obstructive sleep apnea (OSA) according to apnea-hypopnea index. Results Eighty-two patients were included. The majority (70%) had moderate to severe OSA (AHI ≥15). Patients were aged in their mid-40's (45.47 95% CI (42.9, 48.05)) with a tendency to obesity (median BMI 33.67 IQR 30.86, 38.95) and a high prevalence of chronic conditions (72%) (hypertension, diabetes or heart disease). The TESS showed high internal consistency (Split half Spearman correlation=0.71, Cronbach's α =0.81), and a cut-off value ≥3 resulted in sensitivity 84%, specificity 38%. Comparison of area under the curve for TESS to Epworth Sleepiness Scale (ESS) in this sample showed the TESS to have greater sensitivity and specificity overall, which approached significance (p=0.072) when cut-off values of ≥3 and ≥8 (TESS & ESS respectively) were used. The sensitivity and specificity for TESS was also comparable to the other currently used questionnaires, such as the Berlin Questionnaire, STOP-BANG and OSA 50. Conclusion Currently, there are no subjective daytime sleepiness assessment toll available specifically for Indigenous population. The proposed TESS sleepiness screening tool represented in this study can potentially complement or adopted alongside other existing questionnaire, which may offer greater utility in the assessment of sleep disorders among Indigenous people.

Deep Learning for Diagnosis and Classification of Obstructive Sleep Apnea: A Nasal Airflow-Based Multi-Resolution Residual Network.

Abstract: Purpose This study evaluated a novel approach for diagnosis and classification of obstructive sleep apnea (OSA), called Obstructive Sleep Apnea Smart System (OSASS), using residual networks and single-channel nasal pressure airflow signals. Methods Data were collected from the sleep center of the First Affiliated Hospital, Sun Yat-sen University, and the Integrative Department of Guangdong Province Traditional Chinese Medical Hospital. We developed a new model called the multi-resolution residual network (Mr-ResNet) based on a residual network to detect nasal pressure airflow signals recorded by polysomnography (PSG) automatically. The performance of the model was assessed by its sensitivity, specificity, accuracy, and F1-score. We built OSASS based on Mr-ResNet to estimate the apnea‒hypopnea index (AHI) and to classify the severity of OSA, and compared the agreement between OSASS output and the registered polysomnographic technologist (RPSGT) score, assessed by two technologists. Results In the primary test set, the sensitivity, specificity, accuracy, and F1-score of Mr-ResNet were 90.8%, 90.5%, 91.2%, and 90.5%, respectively. In the independent test set, the Spearman correlation for AHI between OSASS and the RPSGT score determined by two technologists was 0.94 (p < 0.001) and 0.96 (p < 0.001), respectively. Cohen's Kappa scores for classification between OSASS and the two technologists' scores were 0.81 and 0.84, respectively. Conclusion Our results indicated that OSASS can automatically diagnose and classify OSA using signals from a single-channel nasal pressure airflow, which is consistent with polysomnographic technologists' findings. Thus, OSASS holds promise for clinical application.

Understanding the Mediating Role of Anxiety and Depression on the Relationship Between Perceived Stress and Sleep Quality Among Health Care Workers in the COVID-19 Response.

Abstract: Objective: There is an increasing amount of evidence exploring the adverse effects of perceived stress or anxiety and depression independently on sleep quality during the COVID-19 outbreak, although the underlying mechanisms are unclear. The aim of the current study was to explore the role of anxiety and depression as a potential mediator between perceived stress and sleep quality among health care workers. Methods: Data were collected through an online survey using the snowball sampling method and comprised 588 current health care workers in Zhejiang and Hubei provinces, China, from February to March 2020. We administered the Sleep Quality Questionnaire (SQQ), the Perceived Stress Scale (PSS-10), the Patient Health Questionnaire (PHQ-4) and the sociodemographic characteristics and COVID-19-related characteristics questionnaire. Structural equation modelling (SEM) was used to examine the direct and indirect relationships between perceived stress, anxiety and depression, and sleep quality. Results: The average scores for sleep quality and perceived stress were 16.01 (95% CI [15.40, 16.57]) and 15.46 (95% CI [15.05, 15.87]), respectively. The positive rates of anxiety and depression symptom tests were 9.86% and 10.37%, respectively. The SEM results indicated that the original relationship between perceived stress and sleep quality was beta = 0.52 (P < 0.001) and reduced to beta = 0.25 (P = 0.045) while introducing anxiety and depression as mediating variables. Perceived stress was positively associated with anxiety and depression (beta = 0.78, P = 0.014), and anxiety and depression were positively associated with sleep quality (beta = 0.42, P < 0.001). Conclusion: Poor sleep quality and high perceived stress were common during the COVID-19 crisis. Reducing perceived stress could help reduce anxiety and depression symptoms, thereby improving sleep quality among health care workers. In an attempt to promote psychological resources, we should perhaps take multiple measures, including personal tailored intervention and organizational humanistic concern.

Insomnia May Mediate the Relationship Between Stress and Anxiety: A Cross-Sectional Study in University Students.

Abstract: Background High perceived stress and anxiety disorders are usually comorbid with each other, with stress often sequentially preceding the development of anxiety. While prior findings showed a causal role of sleep problems in anxiety, no study has assessed the role of insomnia as a mediator in the relationship between stress and anxiety. Methods A cross-sectional study on university students (n = 475, age = 21.1+2.6 years) was conducted over 3 months. Participants completed self-report measures of Leeds Sleep Evaluation Questionnaire-Mizan (LSEQ-M), Perceived Stress Scale-10 (PSS-10), generalized anxiety disorder-7 scale (GAD-7), and a sociodemographic tool. The mediation effect model given by Baron and Kelly was used to determine the relationship. Results The prevalence of insomnia and anxiety disorder was 43.6% and 21.9%, respectively. Stress was significantly associated with LSEQ-M (insomnia measure) (b = -.44, SE = 0.16, p<0.01), and high levels of anxiety (b = 0.25, SE = 0.03, p < 0.01). The indirect effect of stress on anxiety through LSEQ-M (insomnia measure) was significant (95% confidence interval [0.01, 0.04]). However, the indirect effect of anxiety on stress through LSEQ-M (insomnia measure) was non-significant (95% confidence interval [-.01, 0.04]). Conclusions Students having higher perceived stress levels and comorbid insomnia were also likely to have a higher anxiety level.

Circadian Misalignment Rather Than Sleep Duration is Associated with MAFLD: A Population-Based Propensity Score-Matched Study.

Abstract: Background and Aims Circadian misalignment (CM) leads to metabolic disorder. Metabolic (dysfunction) associated fatty liver disease (MAFLD) is a novel definition for fatty liver disease that requires the presence of metabolic dysfunction. As the association between CM and MAFLD remains unclear, this study is designed to explore whether there is an association between CM and MAFLD. Methods NHANES 2017-2018 database was used in this study. Liver steatosis and fibrosis were diagnosed by Fibroscan®. CM was defined by the presence of mistimed sleep, late sleep or irregular chronotype. Propensity score matching (PSM) was used to match subjects for their age and gender. Results A total of 4552 participants were included in the study, with 2089 (45.89%) identified as MAFLD and 894 (19.64%) as CM. Participants with CM were significantly younger than those without (46.06 ± 18.06 vs 50.93 ± 17.78, p<0.001). PSM for age and gender resulted in 894 participants with CM and 892 with non-CM. CM group had higher body mass index, liver enzymes, glucose and lipid levels. The prevalence of MAFLD was higher in the CM group than the non-CM group (45.41% vs 28.48%, p<0.001). The presence of CM increased the risk of MAFLD by more than twofold. Short sleep duration (<6 hours) was not independently associated with MAFLD or fibrosis if additionally adjusting for CM. Conclusion CM is independently associated with MAFLD, while short sleep duration (<6 hours) is not an independent risk factor for MAFLD or liver fibrosis after adjusting for CM.

Excessive Daytime Sleepiness and Cardiovascular Mortality in US Adults: A NHANES 2005–2008 Follow-Up Study

Abstract: Purpose Excessive daytime sleepiness is highly prevalent and has been associated with increased risk of cardiovascular diseases, but evidence for its association with cardiovascular mortality is limited and inconsistent. We aimed to determine whether excessive daytime sleepiness is independently associated with cardiovascular mortality in general adult population. Patients and methods A prospective study of 10,330 adult participants (aged ≥20 years) from National Health and Nutrition Examination Survey (NHANES) 2005-2006 and 2007-2008 was followed up until December 31st, 2015. Excessive daytime sleepiness was defined as the self-reported feeling of being overly sleepy often or always during the day. Cox proportional hazard ratios (HRs) with 95% confidence interval (CI) were estimated to assess risk for cardiovascular mortality. Results A total of 10,330 participants with mean age of 47.3 years (95% CI, 46.0 to 48.1) were included in this analysis. Approximately, 18.5% of US adults reported excessive daytime sleepiness. Over a mean follow-up of 8.3 years, 262 cardiovascular deaths occurred. Participants with excessive daytime sleepiness had 2.85-times greater risk (95% CI, 1.33-6.09) of cardiovascular death than those without daytime sleepiness in multivariable analysis corrected for sociodemographic factors, comorbidities and cardiovascular risk factors including depression. Further adjustment for self-reported sleep disorders and sleep duration only slightly attenuated this association (HR, 2.55; 95% CI, 1.23-5.27). No interactions between excessive daytime sleepiness and age, sex or cardiovascular disease at study entry were observed (all Ps>0.05). Conclusion Excessive daytime sleepiness is highly prevalent among US adults and is independently associated with an approximately two-and-a-half-fold increased risk of cardiovascular mortality in a large national sample. Screening for excessive daytime sleepiness may be a simple and cost-effective tool for identifying individuals at high risk of cardiovascular death.

Profile of Solriamfetol in the Management of Excessive Daytime Sleepiness Associated with Narcolepsy or Obstructive Sleep Apnea: Focus on Patient Selection and Perspectives

Abstract: Excessive sleepiness (ES) is a symptom of obstructive sleep apnea (OSA) and narcolepsy that has severe consequences. Wake-promoting drugs and stimulants are utilized as accessory treatment in OSA to reduce propensity to sleep but they do not improve sleep-disordered breathing. Solriamfetol is a first-line therapeutic agent to combat sleepiness in OSA and narcolepsy patients that is approved both by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA). For excessively sleepy adult patients with OSA despite primary treatment or narcolepsy patients without cataplexy, solriamfetol may be used as initial therapy or as replacement therapy in patients who fail treatment or experience unacceptable side effects with modafinil, armodafinil, pitolisant, or stimulants. It can also be used as add-on therapy in OSA or narcolepsy patients when ES is only partially controlled with modafinil, armodafinil, pitolisant, sodium oxybate, or stimulants. Solriamfetol is a phenylalanine derivative whose wake-promoting action may be mediated through its selective dopamine and norepinephrine reuptake inhibition. This paper reviews the profile of solriamfetol in treating ES associated with OSA or narcolepsy and discusses patient selection and clinical perspectives. Mechanism of action, pharmacology, pharmacokinetics, clinical efficacy, and tolerability of solriamfetol are described. The Treatment of OSA and Narcolepsy Excessive Sleepiness (TONES) solriamfetol trials demonstrated the efficacy of solriamfetol in reducing propensity to sleep and maintaining wakefulness, with significant improvements in mean maintenance of wakefulness test (MWT) sleep latencies and significant reduction in Epworth Sleepiness Scale (ESS) scores compared to placebo. With solriamfetol, significantly higher percentages of patients showed improvement in patient's and clinician's global impression of change.

Relationships Between a Range of Inflammatory Biomarkers and Subjective Sleep Quality in Chronic Insomnia Patients: A Clinical Study.

Abstract: Purpose To examine whether associations exist between chronic insomnia disorder (CID) and overlooked inflammatory factors (Serum amyloid protein A [SAA]), tumor necrosis factor [TNF]-α, granulocyte-macrophage colony-stimulating factor [GM-CSF], and regulated on activation and normal T cell expressed and presumably secreted [RANTES]). Patients and methods A total of 65 CID patients and 39 sex- and age-matched good sleeper (GS) controls participated in this study. They completed a baseline survey to collect data on demographics, and were elevated sleep and mood by Pittsburgh Sleep Quality Index (PSQI), Athens Insomnia Scale (AIS), 17-item Hamilton Depression Rating Scale (HAMD-17) and 14-item Hamilton Anxiety Rating Scale (HAMA-14), respectively. The blood samples were collected and tested the serum levels of SAA, TNF-α, GM-CSF and RANTES. Results The CID group had higher serum levels of SAA, TNF-α, and GM-CSF and a lower level of RANTES than the GS group. In the Spearman correlation analysis, SAA and GM-CSF positively correlated with the PSQI and AIS scores. After controlling for sex, HAMD-17 score, and HAMA-14 score, the partial correlation analysis showed that GM-CSF was positively correlated with PSQI score. Further stepwise linear regression analyses showed that GM-CSF was positively associated with the PSQI and AIS scores, while RANTES was negatively associated with them, and SAA was positively associated with just the AIS score. Conclusion The serum levels of inflammatory mediators (SAA, TNF-α, and GM-CSF) were significantly elevated and the level of RANTES was significantly decreased in CID patients and, to some extent, the changes are related to the severity of insomnia. These findings may help us to improve interventions to prevent the biological consequences of CID by inhibiting inflammation, thereby promoting health.

Spectral Power Analysis of Sleep Electroencephalography in Subjects with Different Severities of Obstructive Sleep Apnea and Healthy Controls.

Abstract: Purpose Previous spectral analysis studies on obstructive sleep apnea (OSA) involved small samples, and the results were inconsistent. We performed a spectral analysis of sleep EEG based on different severities of OSA using the Sleep Heart Health Study data. This study aimed to determine the difference in EEG spectral power during sleep in the non-OSA group and with different severities of OSA in the general population. Patients and Methods The participants (n = 5,804) underwent polysomnography, and they were classified into non-OSA, mild OSA, moderate OSA, and severe OSA groups. The fast Fourier transformation was used to compute the EEG power spectrum for total sleep duration within contiguous 30-second epochs of sleep. The EEG spectral powers of the groups were compared using 4,493 participants after adjusting potential confounding factors that could affect sleep EEG. Results The power spectra differed significantly among the groups for all frequency bands (p corr < 0.001). We found that the quantitative EEG spectral powers in the beta and sigma bands of total sleep differed (p corr < 0.001) among the participants in the non-OSA group and with different severities of OSA, controlling for covariates. The beta power was higher and the sigma power was lower in the OSA groups than in the non-OSA group. The beta power decreased in the order of severe OSA, moderate OSA, mild OSA, and non-OSA. Conclusion This study suggests that there are differences between the microstructures of PSG-derived sleep EEG of non-OSA participants and those with different severities of OSA.

The Development and Accuracy of the THIM Wearable Device for Estimating Sleep and Wakefulness

Abstract: Introduction THIM is a new wearable device worn on the finger that can passively monitor sleep and wakefulness overnight using actigraphy. This article showcases the development of the THIM sleep tracking algorithm (Study 1) and the testing of its accuracy against polysomnography (PSG) with an independent sample of good and poor sleepers (Study 2). The accuracy of THIM was compared to two popular wearables, Fitbit and Actiwatch devices. Methods Twenty-five (Study 1) and twenty (Study 2) healthy individuals with good or poor sleep (defined by scores on the Insomnia Severity Index) slept overnight in the sleep laboratory on one night. Participants slept from their typical bedtime to their typical wake up time with simultaneous recording from PSG, THIM, Fitbit and Actiwatch devices. Results In both studies, THIM had lower sensitivity (M = 0.89-0.91) compared to the Actiwatch (M = 0.95) and Fitbit devices (M = 0.96-0.98), yet higher specificity (M = 0.59 vs M = 0.32-0.59) in detecting sleep. There were no significant differences between PSG and THIM in either study for sleep onset latency, total sleep time, wake after sleep onset, or sleep efficiency, p > 0.06. Yet, there was high variability in the accuracy of all three actigraphy devices between individuals (evident on Bland-Altman plots) that was unexplained by sleep quality. Discussion Together, these studies suggest that THIM is capable of monitoring sleep and wake overnight in good and poor sleepers to a similar degree of accuracy as two of the most popular actigraphy devices available. Future research will examine the accuracy of THIM for monitoring sleep in people with insomnia.

A Single-Center Validation of the Accuracy of a Photoplethysmography-Based Smartwatch for Screening Obstructive Sleep Apnea.

Abstract: Background Obstructive sleep apnea (OSA), the most common upper-airway disease, is closely associated with the risk of cardiovascular diseases. However, the early screening of OSA is a main challenge, relying on polysomnography (PSG) or home sleep apnea test (HSAT) in hospitals. Photoplethysmography (PPG) has been developed as a novel technology for screening of OSA, while the validation of PPG-based smart devices is limited compared to that for PSG or HSAT devices. Objective This study aimed to investigate the feasibility and validity of a PPG-based smartwatch in the screening of OSA. Methods A total of 119 patients were recruited from the Chinese People's Liberty Army General Hospital (Beijing, China). Among them, 20 patients were assessed for a whole-night sleep study by a smartwatch and PSG simultaneously, as well as 82 cases by a smartwatch and HSAT simultaneously. Using PSG or HSAT as the "gold standard", we compared the accuracy, sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and positive likelihood ratio (+LR) or negative likelihood ratio (-LR) at three apnea hypopnea index (AHI) levels: AHI≥5, AHI≥15, and AHI≥30. Results A total of 17/119 patients were excluded from the study due to the poor quality of PPG signals. Among the remaining cases, 83 patients were diagnosed with OSA. Compared to HSAT device, the accuracy, sensitivity, and specificity of the PPG-based smartwatch in predicting moderate-to-severe OSA patients (AHI≥15) were 87.9%, 89.7%, and 86.0%, respectively. Compared to PSG device, the accuracy, sensitivity, and specificity of the PPG-based smartwatch in predicting OSA in patients (AHI≥5) were 81.1%, 76.5%, and 100%, respectively. Conclusion The PPG-based smartwatch outperformed in terms of detecting OSA; nevertheless, validation in a large-scale population is imperative. Trial registration Chinese Clinical Trial Registry of the International Clinical Trials Registry Platform of the World Health Organization ChiCTR-OOC-17014138; http://www.chictr.org.cn/showprojen.aspx?proj=24191.

Short Sleep Duration and Its Association with Obesity and Other Metabolic Risk Factors in Kuwaiti Urban Adults.

Abstract: Background Efficient sleep duration and its quality are increasingly recognized as important contributors for maintaining normal body weight. However, lifestyle and social structure within the Arab-gulf region differ compared to those in the western world. This study was specifically conducted in Kuwait's population to investigate the link between sleep quality (SQ) and obesity in the absence of sleep apnea (SA) onset. Methods SQ was measured by the Pittsburgh Sleep Quality Index (PQSI) in 984 participants, then verified in 60 individuals including 20 lean (Body mass index/BMI: 18.5-24.9 kg/m2), 20 overweight (BMI: 25-29.9 kg/m2) and 20 obese (BMI: ≥30 kg/m2) through actigraph worn over the right-hip for 7 consecutive days to characterize their sleep-wake cycle, rest-activity, and physical activity. Blood samples were collected for metabolic markers. Results 59.6% of participants reported a PSQI score higher than 5, with 57.6% of the participants reporting less than 6 hours of sleep per day. The data show that both SQ and sleep duration are considered inadequate in comparison to the international SQ standards. We found a significant association between SQ and obesity independent of age and sex. Actigraph data further supported the independent association of sleep duration on BMI within the population (p < 0.001). Additionally, total sleep time (TST) was found to significantly correlate with several other metabolic factors including diastolic blood pressure, elevated resting heart rate (RHR), triglycerides, total cholesterol, homeostatic model assessment for insulin resistance (HOMA-IR), C-peptide, and C-Reactive Protein (CRP) secretion. Further multiple-regression analysis showed a significant independent association between blood pressure (p < 0.03), HOMA-IR (p < 0.04), and C-peptide (p < 0.3) and sleep duration. Conclusion These findings suggest that sleep deprivation and disturbance could be indirect factors involved in the development of not only obesity in Kuwait but also other metabolic syndromes such as type 2 diabetes.

Acupuncture: A Promising Approach for Comorbid Depression and Insomnia in Perimenopause.

Abstract: Comorbid depression and insomnia are ubiquitous mental complaints among women going through the perimenopausal stage of life and can result in major decline in quality of life. Antidepressive agents combined with/without hypnotics, and/or hormone therapy are currently the most common treatment for perimenopausal depression (PMD) and insomnia (PMI). Balancing the benefits of these pharmacotherapies against the risk of adverse events (AEs) is a difficult task for both clinicians and women. There has been a growing body of research regarding the utilization of acupuncture for treatment of PMD or PMI, whereas no studies of acupuncture for comorbid PMD and PMI have appeared. In this review, we summarize the clinical and preclinical evidence of acupuncture as a treatment for PMD or PMI, and then discuss the potential mechanisms involved and the role of acupuncture in helping women during this transition. Most clinical trials indicate that acupuncture ameliorates not only PMD/PMI but also climacteric symptoms with minimal AEs. It also regulates serum hormone levels. The reliability of trials is however limited due to methodological flaws in most studies. Rodent studies suggest that acupuncture prolongs total sleep time and reduces depression-like behavior in PMI and PMD models, respectively. These effects are possibly mediated through multiple mechanisms of action, including modulating sex hormones, neurotransmitters, hypothalamic-pituitary-adrenal axis/hypothalamic-pituitary-ovary axis, oxidative stress, signaling pathways, and other cellular events. In conclusion, acupuncture is a promising therapeutic strategy for comorbid depression and insomnia during perimenopause. Neuroendocrine modulation is likely to play a major role in mediating those effects. High-quality trials are required to further validate acupuncture's effectiveness.

A Blue-Enriched, Increased Intensity Light Intervention to Improve Alertness and Performance in Rotating Night Shift Workers in an Operational Setting.

Abstract: Purpose This study examined the efficacy of a lighting intervention that increased both light intensity and short-wavelength (blue) light content to improve alertness, performance and mood in night shift workers in a chemical plant. Patients and methods During rostered night shifts, 28 workers (46.0±10.8 years; 27 male) were exposed to two light conditions each for two consecutive nights (~19:00-07:00 h) in a counterbalanced repeated measures design: traditional-spectrum lighting set at pre-study levels (43 lux, 4000 K) versus higher intensity, blue-enriched lighting (106 lux, 17,000 K), equating to a 4.5-fold increase in melanopic illuminance (24 to 108 melanopic illuminance). Participants completed the Karolinska Sleepiness Scale, subjective mood ratings, and the Psychomotor Vigilance Task (PVT) every 2-4 hours during the night shift. Results A significant main effect of time indicated KSS, PVT mean reaction time, number of PVT lapses (reaction times > 500 ms) and subjective tension, misery and depression worsened over the course of the night shift (p 0.05). Conclusion Our findings, showing improvements in alertness and performance with exposure to blue-enriched, increased intensity light, provide support for light to be used as a countermeasure for impaired alertness in night shift work settings.

Effects of Intravenous Anesthetics vs Inhaled Anesthetics on Early Postoperative Sleep Quality and Complications of Patients After Laparoscopic Surgery Under General Anesthesia.

Abstract: Objective Decreased postoperative sleep quality remains a serious problem in surgical settings at present. The purpose of our study was to compare the effect of propofol vs sevoflurane on early postoperative sleep quality and complications of patients receiving laparoscopic surgery after general anesthesia. Methods Seventy-four patients undergoing selective laparoscopic surgery under general anesthesia were randomly assigned to the propofol group or sevoflurane group. The wireless portable sleep monitor (WPSM) is used to collect sleep quality on the night before surgery (sleep preop 1), the first night after surgery (sleep POD 1), and the third night after surgery (sleep POD 3). Record the subjective sleep quality and dreaming state during the operation. The perioperative hemodynamics, postoperative sleep and complications were also evaluated. Results Compared with Sleep preop 1, patients showed lower sleep efficiency, Stable sleep and Unstable sleep during Sleep POD 1 and Sleep POD 3. In addition, compared with the propofol group, the proportion of REM sleep in the sevoflurane group was much higher during Sleep POD 1 and Sleep POD 3, and the incidence of dreaming was also higher in the sevoflurane group. Patients in the propofol group had better pain relief at 2, 4, and 6 hours after surgery. And the incidence of postoperative nausea and vomiting and dizziness in the sevoflurane group was significantly higher than that in the propofol group. Conclusion The degree of postoperative sleep efficiency was better on Sleep POD1 and Sleep POD3; the incidence of postoperative nausea and vomiting, and dizziness was lower; and postoperative pain was slighter when the operation was performed under propofol anesthesia compared with patients in the sevoflurane group. Propofol should be considered a better choice during the operation to promote the patient's postoperative sleep quality, relieve postoperative pain and improve the incidence of postoperative dizziness and nausea and vomiting.

Nomophobia is Associated with Insomnia but Not with Age, Sex, BMI, or Mobile Phone Screen Size in Young Adults.

Abstract: Purpose NOMOPHOBIA (NO MObile PHone PhoBIA) or problematic smartphone use is a psychological disorder in which people are afraid of being cut off from their mobile phones. Currently, there has been no direct assessment of mobile phone screen size in the home setting and its effect on nomophobia and related symptoms, such as insomnia. Thus, we investigated the association between nomophobia, insomnia, and mobile phone screen size in a young adult population in Bahrain. Patients and Methods Using a descriptive, cross-sectional design, we surveyed participants aged 18 to 35 between August and September 2020 using an online questionnaire. Participants completed demographic questions and questions about personal mobile phones, the Nomophobia Questionnaire (NMP-Q), and the Insomnia Severity Index (ISI). The mobile phone screen size was determined using an open-source online database. Crude and adjusted regression analyses were fitted to examine the associations between the study variables. Results A total of 549 individuals, 54% females, were included in the final analyses. One hundred and fourteen participants (21%) had severe nomophobia, and 81 (14%) had clinical insomnia. A strong positive pair-wise linear association was observed between NMP-Q and ISI β 0.15, P = 0.001. Age, sex, BMI, and mobile phone screen size showed no association with the NMP-Q. Conclusion Nomophobia is very prevalent in young adult men and women, and it is closely associated with insomnia, regardless of mobile phone screen size, suggesting that mobile phone screen size should not be used as a proxy for hazardous usage.

EEG patterns prior to motor activations of parasomnias: A systematic review

Abstract: Introduction Non-rapid eye movement (NREM) parasomnias are defined as abnormal nocturnal behaviors that typically arise from the NREM sleep stage 3 during the first sleep cycle. The polysomnographic studies showed an increase in sleep fragmentation and an atypical slow wave activity (SWA) in participants with NREM parasomnias compared to healthy controls. To date, the pathophysiology of NREM parasomnias is still poorly understood. The recent investigation of the EEG patterns immediately before parasomnia events could shed light on the motor activations' processes. This systematic review aims to summarize empirical evidence about these studies and provide an overview of the methodological issues. Methods A systematic literature search was carried out in PubMed, Web of Science, and Scopus, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The documents obtained were evaluated using the Newcastle-Ottawa Scale (NOS). Results Nine studies were included in the qualitative synthesis. The major evidence revealed an increased slow frequency EEG activity immediately before the motor activations in frontal and central areas and increased beta activity in the anterior cingulate cortices. Discussion The investigation of EEG patterns before parasomniac episodes could provide new insight into the study of NREM parasomnia pathophysiology. The high- and low-frequency EEG increase before the episodes could represent a predictive electrophysiological pattern of the motor activations' onset. Overall, identifying specific sleep markers before parasomnias might also help differentiate between NREM parasomnias and other motor sleep disorders. Different methodological protocols should be integrated for overcoming the lack of consistent empirical findings. Thus, future studies should focus on the topographical examination of canonical EEG frequency bands to better understand spatial and time dynamics before the episodes and identify the networks underlying the onset of activations.

Associations Between Transgender Identity, Sleep, Mental Health and Suicidality Among a North American Cohort of College Students

Abstract: Purpose The purpose of this study is to examine the associations between transgender identity, sleep, and mental health among a North American cohort of cisgender and transgender college students. Participants and methods This cross-sectional study surveyed 221,549 North American college students from the 2016-2017 American College Health Association-National College Health Assessment II. Bivariate and multivariable analysis examined associations among transgender identity and outcomes of insomnia symptoms, daytime sleepiness, sleep disorder diagnoses and treatments. Mental health outcomes included mood symptoms, suicidal behaviors, anxiety and depression diagnoses and treatments. Results Transgender identity was reported by 1.6% (n=3471) of United States (US) and 1.7% (n=717) Canadian students, respectively. Mean age was 22.5 ±6. Transgender college students have an increased prevalence of daytime sleepiness, insomnia symptoms, diagnoses and/or treatment of insomnia and other sleep disorders as compared to cisgender college students. Mental Health symptoms are more prevalent with a 2-fold increase in depression and anxiety and nearly a 4-fold increase in suicide attempts among transgender students. A higher burden of mood symptoms exists among transgender college students in the US in comparison to Canadian students. Conclusion Transgender college students have an alarmingly high rate of mood, sleep disturbances and sleep diagnoses, and suicidality. Colleges and universities must provide sufficient resources to address the sleep and mental health needs of transgender students. Institutions must adopt gender affirming policies that promote an inclusive environment. Increased allocation of resources and adoption of policies that enhance the physical and mental health of transgender students could improve sleep, mood, and potentially lower the suicide risk among a population that often experiences health inequities.