Stable Sleep Research Articles

The substantial role of sleep, stress and physical activity in persistent high levels of fatigue in patients with inflammatory bowel disease: A longitudinal trajectory study.

Fatigue is a common and burdensome problem for patients with inflammatory bowel disease (IBD). Previous studies lack insight into the individual variability in fatigue severity and course over time, and the characteristics of patients at risk of severe and persistent fatigue. This study aimed to identify distinct groups of IBD patients based on their level and course of fatigue over five years. Subsequently, we examined the relationship between these trajectories, patient characteristics and trajectories of perceived stress, sleep and physical activity. This longitudinal cohort study used prospectively collected data from the myIBDcoach telemedicine monitoring tool, including 320 IBD patients who completed three or more online consultations between 2016 and 2021. Latent class growth analyses were performed to identify distinct trajectories. We found five subgroups with distinct trajectories of fatigue, differing in level and course over time, with 33% of patients experiencing chronic stable and high levels of fatigue. Few differences in patient characteristics were found between trajectories, yet the chronic high fatigue subgroup was more likely to report persistent stable sleep problems, perceived stress, and little physical activity over time compared to the other groups. Distinct subgroups of IBD patients can be identified based on longitudinal fatigue trajectories. The relatively stable levels of fatigue, stress, sleep, and physical activity suggest that a one-time screening of patients on these topics may be sufficient to identify those at risk. Interventions aiming to reduce fatigue should target persistent stress, sleep problems, and low levels of physical activity.

Characterizing disrupted nighttime sleep and associated functional outcomes in youth with narcolepsy type 1.

Disrupted nighttime sleep (DNS) and sleep instability are common in children and adolescents with Narcolepsy Type 1 (NT1), but optimal objective sleep measures have not been determined. We compared self-reported and objective sleep measures between young people with NT1 and healthy controls (HC) and test the hypotheses that the Wake/N1 Index is the best objective measure of perceived nocturnal wakings vs. other DNS measures reported in the literature and is associated with daytime functional problems. N=26 HC and N=27 NT1 participants ages 8-21 years completed a 15-item habitual sleep quality survey and an in-lab polysomnogram. We compared group survey responses and performed stepwise regression of sleep quality and instability measures with a survey question ("During the night, I wake more than once"). Last, we used logistic regression to identify associations between the Wake/N1 Index with daytime functional concerns across groups. Compared to HC, NT1 participants reported more frequent restless sleep, nighttime moaning/groaning/talking, tossing and turning, and nocturnal wakings (all p's < 0.01), but no greater difficulties in falling asleep or returning back to sleep. Across groups, self-reported waking from sleep was associated with increased Wake/N1 Index and SSRI/SNRI use. The Wake/N1 Index was associated with daytime fatigue but no other behavioral or cognitive concerns. DNS is a multi-factorial complaint that differs from insomnia. We believe the Wake/N1 Index is a useful sleep instability measure that should be helpful in research and as a treatment target in clinical practice, especially for fatigue concerns.

Nocturnal Sleep Dynamics Alterations in the Early Stages of Behavioral Variant Frontotemporal Dementia.

Sleep disorders have been recognized as an integral component of the clinical syndrome in several neurodegenerative diseases, including Alzheimer's Disease (AD). However, limited data exists for rarer types of neurodegenerative diseases, such as behavioral variant Frontotemporal Dementia (bvFTD). This study aims to analyze EEG power spectra and sleep stage transitions in bvFTD patients, hypothesizing that bvFTD may show distinctive sleep stage transitions compared to patients with Alzheimer's Disease (AD). Eighteen probable bvFTD patients and eighteen age- and sex-matched probable AD patients underwent overnight polysomnography (PSG) and completed sleep disorders questionnaires. Sleep questionnaires, full-night EEG spectra, and sleep stage transitions indexes were compared between groups. bvFTD patients had higher Insomnia Severity Index (ISI) scores (95%CI: 0, 5) and reported poorer sleep quality than AD patients (p<0.01). Compared to AD, bvFTD patients showed higher N1 percentage (95%CI: 0.1, 6), lower N3 percentage (95%CI: -13.6, -0.6), higher sleep-wake transitions (95%CI: 1.49, 8.86) and N1 sleep-wake transitions (95%CI: 0.32, 6.1). EEG spectral analysis revealed higher spectral power in bvFTD compared to AD patients in faster rhythms, especially sigma rhythm, across all sleep stages. In bvFTD patients, sleep-wake transitions were positively associated with ISI. Patients with bvFTD present higher rates of transitions between wake and sleep than AD patients. The increased frequency of sleep transitions indicates a higher degree of sleep instability in bvFTD, which may reflect an imbalance in sleep-wake promoting systems. Sleep stage transitions analysis may provide novel insights into the sleep alterations of bvFTD patients.

Cyclic Alternating EEG Patterns: From Sleep to Encephalopathy.

In the 2021 version of the Standardized Critical Care EEG Terminology, the American Clinical Neurophysiology Society introduced new definitions, including for the cyclic alternating pattern of encephalopathy (CAPE). CAPE refers to changes in background EEG activity, with two patterns alternating spontaneously in a regular manner. CAPE shares remarkable similarities with the cyclic alternating pattern, a natural EEG phenomenon occurring in normal non-rapid eye movement sleep, considered the main electrophysiological biomarker of sleep instability. This review explores similarities and differences between cyclic alternating pattern and CAPE and, leveraging the existing expertise on cyclic alternating pattern, aims to extend knowledge on CAPE. A standardized assessment of CAPE features is key to ascertain its prevalence and clinical significance among critically ill patients and to encompass the impact of confounding factors such as anesthetic and sedative agents. Although the preservation of non-rapid eye movement sleep-related elements has a well-known prognostic value in the critical care setting, the clinical importance of cyclic oscillating patterns and the prognostic significance of CAPE remain to be elucidated.

Five-year changes in 24-hour sleep-wake activity and dementia risk in oldest old women.

Sleep disruptions are associated with cognitive aging in older adults. However, it is unclear whether longitudinal changes in 24-hour multidimensional sleep-wake activity are linked to cognitive impairment in the oldest old. We studied 733 cognitively unimpaired women (mean age=82.5±2.9 years) who completed two actigraphy assessments over five years. We performed hierarchical clustering on principal components in nine sleep, napping, and circadian rest-activity rhythm parameters to identify multidimensional sleep-wake change profiles and multinomial logistic regression to evaluate the associations between sleep-wake changes and risk of cognitive impairment at follow-up. We identified three sleep-wake change profiles: Stable Sleep (43.8%), Declining Nighttime Sleep (34.9%), and Increasing Sleepiness (21.3%). After adjustment for demographics and comorbidities, women with Increasing Sleepiness had approximately doubled (odds ratio=2.21, p=0.018) risk of dementia compared to those with Stable Sleep. Increasing sleepiness may be an independent marker or risk factor for dementia in oldest old women.

The relationship between rapid eye movement electromyogram activity and sleep stability in rapid eye movement sleep behavior disorder

Objective: To investigate the relationship between the types of electromyogram (EMG) activity and sleep stability during rapid eye movement (REM) in patients with rapid eye movement sleep behavior disorder(RBD). Methods: One hundred and three patients with RBD who met the inclusion and exclusion criteria at the Second Affiliated Hospital of Air Force Military Medical University from January 2017 to December 2019 were retrospectively analyzed. The general situation, clinical symptoms, sleep and emotion questionnaires and nocturnal PSG data were collected. According to the different proportions of tonic and phasic EMG activity, the group with a higher proportion of tonic EMG than phasic EMG was defined as the tonic dominant group, and the group with a higher proportion of phasic EMG than tonic was defined as the phasic dominant group. The sleep instability index was calculated according to the ratio of the number of transitions from sleep to wakefulness to the total sleep time of each sleep stage. Multiple linear regression was used to explore the relationship between REM EMG activity and sleep instability index. Results: A total of 35 idiopathic RBD (iRBD) patients were included, aged(54.5±18.2)years, with 17 males and 18 females. There were 27 RBD with Parkinson's disease (PD), with an average age of (59.4±7.9)years, including 17 males and 10 females. Additionally, there were 41 RBD patients with narcolepsy, aged (21.2±13.2)years, consisting of 22 males and 19 females. Both iRBD and RBD patients with PD had lower objective total sleep time, sleep latency, sleep efficiency, wake time after sleep onset and the percentage of N3 sleep compared to RBD with episodic sleep disorder (all P<0.05). N1-W index[M(Q1, Q3),10.6 (6.5, 16.9)/h vs 7.3 (4.7, 10.5)/h], N2-W index [4.0 (2.2, 5.6)/h vs 2.3 (1.5, 3.9)/h], NREM-W index [ (5.8±2.9)/h vs (4.5±3.2)/h] and REM-W index[ 3.9 (1.9, 7.3)/h vs 2.7 (1.0, 4.0)/h] in the phasic dominant group were higher than those in the tonic dominant group. After adjusting for confounding factors, the effect of phasic EMG dominant group on REM-W was higher than that in the tonic dominant group (β=2.05, 95%CI: 0.09-3.26, P=0.012). Conclusion: In RBD patients, the phasic EMG activity has a significant impact on sleep stability, especially on REM sleep stability.

REM sleep breathing: Insights beyond conventional respiratory metrics.

Breathing and sleep state are tightly linked. The traditional approach to evaluation of breathing in rapid eye movement sleep has been to focus on apneas and hypopneas, and associated hypoxia or hypercapnia. However, rapid eye movement sleep breathing offers novel insights into sleep physiology and pathology, secondary to complex interactions of rapid eye movement state and cardiorespiratory biology. In this review, morphological analysis of clinical polysomnogram data to assess respiratory patterns and associations across a range of health and disease is presented. There are several relatively unique insights that may be evident by assessment of breathing during rapid eye movement sleep. These include the original discovery of rapid eye movement sleep and scoring of neonatal sleep, control of breathing in rapid eye movement sleep, rapid eye movement sleep homeostasis, sleep apnea endotyping and pharmacotherapy, rapid eye movement sleep stability, non-electroencephalogram sleep staging, influences on cataplexy, mimics of rapid eye movement behaviour disorder, a reflection of autonomic health, and insights into cardiac arrhythmogenesis. In summary, there is rich clinically actionable information beyond sleep apnea encoded in the respiratory patterns of rapid eye movement sleep.

The stability of slow-wave sleep and EEG oscillations across two consecutive nights of laboratory polysomnography in cognitively normal older adults.

Laboratory polysomnography provides gold-standard measures of sleep physiology, but multi-night investigations are resource intensive. We assessed the night-to-night stability via reproducibility metrics for sleep macrostructure and electroencephalography oscillations in a group of cognitively normal adults attending two consecutive polysomnographies. Electroencephalographies were analysed using an automatic algorithm for detection of slow-wave activity, spindle and K-complex densities. Average differences between nights for sleep macrostructure, electroencephalography oscillations and sleep apnea severity were assessed, and test-retest reliability was determined using two-way intraclass correlations. Agreement was calculated using the smallest real differences between nights for all measures. Night 2 polysomnographies showed significantly greater time in bed, total sleep time (6.3 hr versus 6.8 hr, p < 0.001) and percentage of rapid eye movement sleep (17.5 versus 19.7, p < 0.001). Intraclass correlations were low for total sleep time, percentage of rapid eye movement sleep and sleep efficiency, moderate for percentage of slow-wave sleep and percentage of non-rapid eye movement 2 sleep, good for slow-wave activity and K-complex densities, and excellent for spindles and apnea-hypopnea index with hypopneas defined according to 4% oxygen desaturation criteria only. The smallest real difference values were proportionally high for most sleep macrostructure measures, indicating moderate agreement, and proportionally lower for most electroencephalography microstructure variables. Slow waves, K-complexes, spindles and apnea severity indices are highly reproducible across two consecutive nights of polysomnography. In contrast, sleep macrostructure measures all demonstrated poor reproducibility as indicated by low intraclass correlation values and moderate agreement. Although there were average differences in percentage of rapid eye movement sleep and total sleep time, these were numerically small and perhaps functionally or clinically less significant. One night of in-laboratory polysomnography is enough to provide stable, reproducible estimates of an individual's sleep concerning measures of slow-wave activity, spindles, K-complex densities and apnea severity.

Chronic insomnia, REM sleep instability and emotional dysregulation: A pathway to anxiety and depression?

The world-wide prevalence of insomnia disorder reaches up to 10% of the adult population. Women are more often afflicted than men, and insomnia disorder is a risk factor for somatic and mental illness, especially depression and anxiety disorders. Persistent hyperarousals at the cognitive, emotional, cortical and/or physiological levels are central to most theories regarding the pathophysiology of insomnia. Of the defining features of insomnia disorder, the discrepancy between minor objective polysomnographic alterations of sleep continuity and substantive subjective impairment in insomnia disorder remains enigmatic. Microstructural alterations, especially in rapid eye movement sleep ("rapid eye movement sleep instability"), might explain this mismatch between subjective and objective findings. As rapid eye movement sleep represents the most highly aroused brain state during sleep, it might be particularly prone to fragmentation in individuals with persistent hyperarousal. In consequence, mentation during rapid eye movement sleep may be toned more as conscious-like wake experience, reflecting pre-sleep concerns. It is suggested that this instability of rapid eye movement sleep is involved in the mismatch between subjective and objective measures of sleep in insomnia disorder. Furthermore, as rapid eye movement sleep has been linked in previous works to emotional processing, rapid eye movement sleep instability could play a central role in the close association between insomnia and depressive and anxiety disorders.

Circuit mechanism underlying fragmented sleep and memory deficits in 16p11.2 deletion mouse model of autism.

Sleep disturbances are prevalent in children with autism spectrum disorder (ASD) and have a major impact on the quality of life. Strikingly, sleep problems are positively correlated with the severity of ASD symptoms, such as memory impairment. However, the neural mechanisms underlying sleep disturbances and cognitive deficits in ASD are largely unexplored. Here, we show that non-rapid eye movement sleep (NREMs) is highly fragmented in the 16p11.2 deletion mouse model of ASD. The degree of sleep fragmentation is reflected in an increased number of calcium transients in the activity of locus coeruleus noradrenergic (LC-NE) neurons during NREMs. Exposure to a novel environment further exacerbates sleep disturbances in 16p11.2 deletion mice by fragmenting NREMs and decreasing rapid eye movement sleep (REMs). In contrast, optogenetic inhibition of LC-NE neurons and pharmacological blockade of noradrenergic transmission using clonidine reverse sleep fragmentation. Furthermore, inhibiting LC-NE neurons restores memory. Rabies-mediated unbiased screening of presynaptic neurons reveals altered connectivity of LC-NE neurons with sleep- and memory regulatory brain regions in 16p11.2 deletion mice. Our findings demonstrate that heightened activity of LC-NE neurons and altered brain-wide connectivity underlies sleep fragmentation in 16p11.2 deletion mice and identify a crucial role of the LC-NE system in regulating sleep stability and memory in ASD.

Changes in sleep score and leisure-time physical activity, their combination, and all-cause mortality in middle-aged and older Chinese adults: The Dongfeng-Tongji cohort study

ObjectivesTo prospectively investigate the associations of longitudinal changes in sleep score and LTPA and their combination with all-cause mortality. MethodsAmong 12,543 participants (mean age: 66.1 years) from the Dongfeng-Tongji cohort, we calculated sleep score (range, 0–4, integrating bedtime, sleep duration, sleep quality, and midday napping, higher score indicating healthier sleep) and LTPA at baseline (2008–2010) and the first follow-up (2013) surveys and their 5-year changes (defining stable sleep score as no change and stable LTPA as change within 150 min/week). We prospectively documented deaths from the first follow-up survey (2013) through December 31, 2018. ResultsDuring a mean 5.5-year follow-up, 792 deaths occurred. The 5-year changes in sleep score and LTPA were inversely associated with all-cause mortality risk, regardless of their initial values. When assessing 5-year changes in sleep score and LTPA jointly, compared with the stable sleep score-stable LTPA group, the decreased sleep score-decreased LTPA group had a 40 % (5–85 %) higher all-cause mortality risk, whereas the increased sleep score-increased LTPA group had a 34 % (9–52 %) lower risk. The direction of the joint association was mainly driven by sleep score change. Participants maintaining sleep scores ≥ 3 and LTPA ≥ 150 min/week over 5 years had a 44 % (28–56 %) lower all-cause mortality risk. ConclusionsPromoting sleep hygiene and LTPA together may benefit efforts in reducing mortality risk, with particular attention to monitoring long-term sleep health.

Assessment of Effects of Carbon Dioxide Exposure on Sleep Stability in Insomnia Using the Envelope Analysis

Objectives: Insomnia is a common sleep disorder, and various strategies have been explored for its treatment. One of the methods involves the administration of carbon dioxide (CO&lt;sub&gt;2&lt;/sub&gt;) at bedtime, as the CO&lt;sub&gt;2&lt;/sub&gt; increment exerts a sedative effect on the central nervous system. We aimed to assess the effect of CO&lt;sub&gt;2&lt;/sub&gt; on sleep quality in patients with insomnia using the coefficient of variation of the envelope (CVE) analysis, a novel analytical method. Methods: In this randomized, double-blind, sham-controlled crossover trial, 24 adults with sleeping difficulties underwent level 1 polysomnography. Two interventions involved exposure to either 2% low-concentration CO&lt;sub&gt;2&lt;/sub&gt; gas or room air. CVE analysis was performed to assess the stability of the delta band. Morphological variations in delta waves can be quantitatively monitored using the envelope analysis, which assesses the effect of manipulations on sleep that may otherwise elude detection. Results: Exposure to CO&lt;sub&gt;2&lt;/sub&gt; improved the total sleep time (TST) (&lt;i&gt;p&lt;/i&gt;=0.010) and total arousal index (TAI) (&lt;i&gt;p&lt;/i&gt;=0.011). The CVE analysis showed a distinct distribution between the experimental and sham-controlled groups. Moreover, correlations between the TST and CVE (r=0.41) and those between the TAI and CVE (r=0.40) were observed. Conclusions: This study is the first to evaluate the effects of CO&lt;sub&gt;2&lt;/sub&gt; exposure on sleep stability in patients with insomnia. The CVE analysis implies the possibility of sleep stabilization by CO&lt;sub&gt;2&lt;/sub&gt; administration and suggests a link between enhanced sleep maintenance and sleep stability.

Association between longitudinal change of sleep patterns and the risk of cardiovascular diseases.

To investigate the role of longitudinal change of sleep patterns in the incidence of cardiovascular diseases (CVD). Based on UK Biobank, a total of 18 172 participants were enrolled. Five dimensions of healthy sleep including early chronotype, sleep 7-8 hours/day, free of insomnia, no snoring, and no frequent excessive daytime sleepiness were used to generate a healthy sleep score (HSS) ranging from 0 to 5. Corresponding to the HSS of 0-1, 2-3, and 4-5, the poor, intermediate, and healthy sleep patterns were defined. Based on changes in HSS across assessments 1 and 2, we calculated the absolute difference of HSS. For the change in sleep patterns, we categorized five profiles (stable healthy, worsening, stable intermediate, optimizing, and stable poor sleep patterns). The outcomes were incidence of CVD including coronary heart disease (CHD) and stroke. We assessed the adjusted hazard ratios and 95% confidence intervals (CIs) by Cox hazard models. Compared with participants with stable poor patterns, those who improved their sleep patterns or maintained healthy sleep patterns had a 26% and 32% lower risk of CVD, respectively. Stable healthy sleep pattern was associated with a 29% and 44% reduced risk of CHD and stroke. Per unit, longitudinal increment of the HSS was related to an 8% lower risk of CVD and CHD. Compared with individuals with constant HSS, those with decreased HSS had a 13% higher risk of developing CVD. Optimizing sleep patterns and maintaining a healthy sleep pattern may reduce the risk of CVD.

Dynamic Associations Among Sleep, Emotion Dysregulation, and Desire to Live in a Perinatal Sample.

The present study prospectively examined dynamic associations among sleep, emotion dysregulation, and desire to live during the perinatal transition, as it was theorized that these factors may contribute to the emergence of postpartum suicide risk. Ninety-four women ( Mage = 29.2 years; 23.4% Latina) wore wrist actigraphs and completed twice daily surveys for 7 days during the third trimester of pregnancy, 6 weeks postpartum, and 4 months postpartum. Multilevel, change-as-outcome models were built to examine changes in attractor dynamics among sleep, emotion dysregulation, and desire to live, as well as if sleep-emotion dysregulation dynamics differed based on participants' desires to live. From pregnancy to 6 weeks postpartum, emotion dysregulation ( B = -0.09, p = .032) and desire to live ( B = -0.16, p < .001) exhibited more stable temporal patterns around higher emotion dysregulation and lower desire to live. Compared to women who reported consistently high desires to live, those who experienced fluctuations in their desires to live exhibited lower, more stable sleep efficiency during pregnancy ( B = -0.90, p < .001). At 4 months postpartum, those with fluctuating desires to live exhibited a coupling dynamic whereby low sleep efficiency predicted increases in emotion dysregulation ( B = -0.16, p = .020). This study was the first to examine nonlinear dynamics among risk factors for postpartum suicide, which may be evident as early as pregnancy and 6 weeks postpartum. Sleep health, in particular, warrants further exploration as a key susceptibility factor in the emergence of postpartum suicide risk. Open Science Framework ( https://osf.io/qxb75/?view_only=799ffe5c048842dfb89d3ddfebaa420d ).

Sleep-phasic heart rate variability predicts stress severity: Building a machine learning-based stress prediction model.

We propose a novel approach for predicting stress severity by measuring sleep phasic heart rate variability (HRV) using a smart device. This device can potentially be applied for stress self-screening in large populations. Using a Holter electrocardiogram (ECG) and a Huawei smart device, we conducted 24-h dual recordings of 159 medical workers working regular shifts. Based on photoplethysmography (PPG) and accelerometer signals acquired by the Huawei smart device, we sorted episodes of cyclic alternating pattern (CAP; unstable sleep), non-cyclic alternating pattern (NCAP; stable sleep), wakefulness, and rapid eye movement (REM) sleep based on cardiopulmonary coupling (CPC) algorithms. We further calculated the HRV indices during NCAP, CAP and REM sleep episodes using both the Holter ECG and smart-device PPG signals. We later developed a machine learning model to predict stress severity based only on the smart device data obtained from the participants along with a clinical evaluation of emotion and stress conditions. Sleep phasic HRV indices predict individual stress severity with better performance in CAP or REM sleep than in NCAP. Using the smart device data only, the optimal machine learning-based stress prediction model exhibited accuracy of 80.3 %, sensitivity 87.2 %, and 63.9 % for specificity. Sleep phasic heart rate variability can be accurately evaluated using a smart device and subsequently can be used for stress predication.

Comparative Analysis of Sleep Hygiene and Patterns among Adolescents in Two Russian Arctic Regions: A Pilot Study.

The circumpolar habitat stands as one of the most vulnerable environments for human activity and health. The primary study objective was to compare sleep-related factors, light exposure, social cues, and potential confounding variables among schoolchildren residing in the European Arctic region from two settlements situated below and above the Polar Circle using validated self-reported questionnaires. We recruited 94 children aged 13-15 years (40.4% males), matched by sex and age, from public educational institutions in two circumpolar settlements located below (Kem', Republic of Karelia; 64.6 NL) and above the Polar Circle (Apatity, Murmansk Region; 67.3 NL). Participants completed several surveys, including the Pediatric Daytime Sleepiness Scale, the Insomnia Severity Index, the Adolescent Sleep Hygiene Scale, and the Munich ChronoType Questionnaire, to evaluate sleep parameters and chronotype. The χ2 test was used to test for differences between proportions. Linear regression and multiple regression models with co-factors were applied to assess the relationship between studied indicators. A noteworthy increase in physical activity was observed in children residing in Kem' compared to those in Apatity. Children from Apatity showed higher alcohol consumption than their counterparts from Kem'. The overall rate of excessive daytime sleepiness in the sample was 17.1%. Moderate insomnia symptoms were reported in 18.4% of adolescents living in Kem' and in 25% of respondents living in Apatity, respectively. Notably, participants from Kem' attained higher academic scores and had longer exposure to sunlight on schooldays. On the other hand, children from Apatity tended to have later bedtimes and sleep-onset times on schooldays. According to the Munich ChronoType Questionnaire data, a reliance on alarm clocks on schooldays, and a higher Sleep Stability Factor based on the Adolescent Sleep Hygiene Scale. Our study indicating that higher physical activity and longer sunlight exposure among Kem' children on schooldays are associated with earlier wake-up times during schooldays, earlier bedtime whole week, reduced dependence on alarm clocks, and higher academic achievements. The results of older schoolchildren differ from many works published previously in the USA, Argentina, and Japan, which could be explained by the season when the study was performed. Here, we observed a negative impact on school performance and sleep parameters in children living in high latitudes, namely in circumpolar regions. Our study points out that adolescents living above the Polar Circle tend to have sleep problems, e.g., late sleep-onset times, higher excessive daytime sleepiness, and insomnia-related symptoms, because of experiencing reduced exposure to natural light. Future research encompassing assessments across all four seasons will provide a more comprehensive understanding.

518 - Interaction of sleep disturbance and nocturnal scratch in atopic dermatitis patients

Abstract Introduction/Background Itch, scratch and poor sleep are often cited as key symptoms of Atopic Dermatitis (AD). Although approximately 10-41% of children and 7-48% of adults in the general population experience sleep disturbances, this figure climbs to 47-80% in children with AD and 33-90% in adults with AD (Bawany et al., 2021). While great effort has been done to characterize and validate nocturnal scratch and sleep, the relationship between the two remains poorly characterized. Objectives We hypothesize that nocturnal scratch is the reason for the sleep disturbances in patients with AD. Literature suggests that these symptoms are linked, albeit not necessarily causal. Here we investigate the interaction between nocturnal scratch events and sleep disturbances in study participants with AD compared to a healthy cohort. Methods Patients with AD (n=185) and without AD (n=40) aged between 2 to 75 years were recruited across three different studies. Study participants spent the night in a qualified sleep lab while being under observation with thermal videography and polysomnography (PSG). The thermal videography was annotated for both scratch and non-scratch movements by two trained annotators independently with any conflicts being resolved by an arbitrator. The PSG was scored by a credentialed technologist in 30-s epochs per revised American Academy of Sleep Medicine scoring guidelines. The study participants also wore a wrist-worn accelerometer on both the left and right wrists. Results It was noted that sleep disturbances were associated with the observed scratch events, and that the temporal relationship between sleep disturbance and scratching seemed to differ between the AD and healthy cohorts. Surprisingly, however, it was also noted that within a few study participants with AD, scratch events occurred while the patient was in stable REM sleep, most often in the children with AD. Further investigation will provide additional information as to whether this was an artifact or in fact a true observation. We also present an overview of sleep, as well as nocturnal scratch and non-scratch movements in the AD and healthy cohorts, noting specifically how the behaviors differ between the groups, and over the course of the sleep opportunity, across sleep stages and sleep cycles, as well as their relationships to sleep disturbances. Conclusions Nocturnal scratching is often associated with sleep disturbances in AD; however, the causality is not always clear. Moreover, in some cases scratching was observed during stable REM sleep in AD, an observation that requires further investigation.

Vigilance during recurrent variable and stable short sleep schedules in young adults

Vigilance during recurrent variable and stable short sleep schedules in young adults

The effects of insufficient sleep and adequate sleep on cognitive function in healthy adults

Study objectivesAlthough sleep affects a range of waking behaviors, the majority of studies have focused on sleep loss with relatively little attention on sustained periods of adequate sleep. The goal of this study was to use an experimental design to examine the effect of both of these sleep patterns on cognitive performance in healthy adults. MethodsThis study used a randomized crossover design. Participants who regularly slept 7-9 hours/night completed two 6-week intervention conditions, adequate sleep (maintenance of habitual bed/wake times) and insufficient sleep (reduction in sleep of 1.5 hours relative to adequate sleep), separated by a 2-6weeks (median=43days) washout period. Cognitive functioning was evaluated at baseline and endpoint of each intervention using the NIH Toolbox Cognition Battery. General linear models contrasted scores following each condition to the baseline of the first condition; the baseline of the second condition was included to evaluate practice effects. ResultsSixty-five participants (age 35.9 ± 4.9years, 89% women, 52% non-White race/ethnicity) completed study procedures. There was improvement in performance on the List Sorting Working Memory task after the adequate sleep condition that exceeded practice effects. Cognitive performance after insufficient sleep did not reach the level expected with practice and did not differ from baseline. A similar pattern was found on the Flanker Inhibitory Control and Attention task. ConclusionsThese findings contribute to our understanding of the complex interplay between sleep and cognition and demonstrate that consistent, stable sleep of at least 7 hours/night improves working memory and response inhibition in healthy adults. Clinical Trial RegistrationThe manuscript reports on data from two clinical trials: Impact of Sleep Restriction on Performance in Adults (URL: https://clinicaltrials.gov/ct2/show/NCT02960776, ID Number: NCT02960776) and Impact of Sleep Restriction in Women (URL: https://clinicaltrials.gov/ct2/show/NCT02835261, ID Number: NCT02835261).

Sleep Analysis by Evaluating the Cyclic Alternating Pattern A Phases

Sleep is a complex process divided into different stages, and a decrease in sleep quality can lead to adverse health-related effects. Therefore, diagnosing and treating sleep-related conditions is crucial. The Cyclic Alternating Pattern (CAP) is an indicator of sleep instability and can assist in assessing sleep-related disorders such as sleep apnea. However, manually detecting CAP-related events is time-consuming and challenging. Therefore, automatic detection is needed. Despite their usually higher performance, the utilization of deep learning solutions may result in models that lack interpretability. Addressing this issue can be achieved through the implementation of feature-based analysis. Nevertheless, it becomes necessary to identify which features can better highlight the patterns associated with CAP. Such is the purpose of this work, where 98 features were computed from the patient’s electroencephalographic signals and used to train a neural network to identify the CAP activation phases. Feature selection and model tuning with a genetic algorithm were also employed to improve the classification results. The proposed method’s performance was found to be among the best state-of-the-art works that use more complex models.