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Background and Aims: Overweight and obesity in children have become a global public health problem. Epidemiological studies suggest that sleep duration may contribute to the incidence of overweight and obesity in all stages of life. China has an increasing prevalence of overweight and obesity, and sleep deprivation is common among Chinese children. The aim of this study was to assess the prospective relationship between short sleep duration and overweight or obesity in Chinese children and to gain an estimate of the risk., Methods and Results: A systematic search was performed on 28/04/2020 by using Medline, PubMed and Web of Science. The exposure was the duration of sleep, and the outcome measure the incidence of overweight or obesity. The odds ratios (OR) and hazard ratios (HR) and 95% confidence intervals (C.I.) were extracted to calculate the pooled relative risk (RR) by a random effect model. Heterogeneity and publication bias of the studies were checked by sensitivity analysis. Seven studies fulfilled the criteria for a systematic review, and 5 studies for a meta-analysis. The total of 33,206 participants included boys and girls, aged 6-17 years old. In Chinese children the pooled RR for short sleep duration and overweight or obesity combined was 1.47 (95% C.I. 1.26, 1.71, p < 0.00001, n = 32,607), and for obesity alone 1.40 (95% C.I. 1.01, 1.95, p = 0.04, n = 17,038). There was no significant heterogeneity or publication bias between studies., Conclusion: Short sleep duration is associated with the development of overweight and obesity in Chinese children., Competing Interests: Declaration of competing interest YG, MAM, and FPC have no relevant conflicts of interest to declare. All the authors approved the final version of this manuscript., (Copyright © 2020 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.)

Background: ICU survivors can experience both cognitive dysfunction and persistent sleep disturbances after hospitalization. Sleep disturbances have been linked with cognitive impairment in various patient populations, and the apolipoprotein E (APOE) genotype has been linked to sleep-related impairments in cognition., Research Question: Is there an association between sleep, long-term cognition, and APOE status in ICU survivors?, Study Design and Methods: We enrolled 150 patients from five centers who had been mechanically ventilated for at least 3 days; 102 patients survived to ICU discharge. Actigraphy and cognitive testing were undertaken at 7 days, 6 months, and 12 months after ICU discharge, and sleep duration, quality, and timing were estimated by actigraphy. APOE single nucleotide polymorphisms were assessed for each patient., Results: Actigraphy-estimated sleep fragmentation, but not total sleep time or interdaily stability (estimate of circadian rhythmicity), was associated with worse cognitive impairment at 7 days of ICU discharge. No actigraphy-estimated variable of sleep estimation at 7 days post-ICU discharge predicted cognitive impairment or persistent sleep abnormalities at 6 and 12 months of follow-up in subsequently assessed survivors. Possessing the APOE ε4 allele was not significantly associated with sleep disturbances and its presence did not modify the risk of sleep-related cognitive impairment at follow-up., Interpretation: Sleep fragmentation estimated by actigraphy was associated with worse cognitive performance in hospital, but not at later time intervals. Further research is needed to better delineate the relationship between persistent sleep disturbances and cognition in larger numbers of ICU survivors., Trial Registry: ClinicalTrials.gov; No.: NCT02086877; URL: www.clinicaltrials.gov., (Copyright © 2020 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

Background: Chronically ill children and their parents are at risk for sleep disorders and associated morbidity. Sleep disturbance prevalence and the relationships between parent and child sleep among children with CF are not well defined. Clarifying the presence and impact of sleep disturbances among pediatric CF patients and their parents could lead to improved health in this population., Methods: Cross-sectional study assessing parent-reported sleep in ninety-one CF patients (mean age 8.8 years; 53.8% female) and their primary caregivers. Sleep sufficiency determined using American Academy of Sleep Medicine guidelines; correlation coefficients computed for sleep problem domains; stepwise multiple linear regression determined predictive models for sleep duration., Results: Parents reported concerns about their own sleep and that of their children. Night waking and daytime sleepiness were most common in parents; prolonged sleep latency was most common for children. Most parents and children had inadequate sleep duration. School-age children had the highest frequencies of overall sleep concerns and inadequate sleep. Most parent and child sleep problem domains were significantly associated, with large effects for similar parent and child problems. Stepwise multiple linear regression demonstrated that CF caregiver/patient sleep duration was significantly predicted by insomnia symptoms., Conclusions: Many CF children and their parents experience sleep difficulties including inadequate sleep duration, with presence of sleep problems in many families whose children with CF had normal lung function. These data suggest that sleep health should be a CF Care Model component and should be a health care focus for families of children with other chronic illness., Competing Interests: Declaration of Conflict of Interest None., (Copyright © 2020 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

Background: OSA and short sleep duration (SSD) are frequently associated with daytime symptoms and cardiometabolic deregulation. However, the vast majority of studies addressing OSA have not evaluated SSD, and vice versa. Our aim was to evaluate the association of OSA, SSD, and their interactions with sleepiness and cardiometabolic risk factors in a large cohort of adults., Methods: Consecutive subjects from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) participated in clinical evaluations, sleep questionnaires, home sleep monitoring, and actigraphy. OSA was defined as an apnea-hypopnea index ≥ 15 events/hour. SSD was defined by a mean sleep duration < 6 h., Results: Data from 2,064 participants were used in the final analysis (42.8% male; mean age, 49 ± 8 years). The overall frequency of OSA and SSD were 32.9% and 27.2%, respectively. Following an adjustment for multiple confounding factors, excessive daytime sleepiness was independently associated with SSD (OR, 1.448; 95% CI, 1.172-1.790) but not with OSA (OR, 1.107; 95% CI, 0.888-1.380). The SSD interaction with OSA was not significant. Prevalent obesity (OR, 3.894; 95% CI, 3.077-4.928), hypertension (OR, 1.314; 95% CI, 1.035-1.667), and dyslipidemia (OR, 1.251; 95% CI, 1.006-1.555) were independently associated with OSA but not with SSD. Similarly, the interactions of OSA with SSD were not significant. An additional analysis using < 5 h for SSD or continuous sleep duration did not change the lack of association with the cardiometabolic risk factors., Conclusions: Objective SSD but not OSA was independently associated with daytime sleepiness. By contrast, OSA, but not SSD, was independently associated with obesity, hypertension, and dyslipidemia., (Copyright © 2018 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

Objective: Sleep deprivation has a negative effect on neurocognitive performance. The King-Devick test (KDT), which tests speed and accuracy of number-reading, requires integrity of saccades, visual processing, and cognition. This study investigated effects of sleep deprivation in on-call residents using KDT., Methods: A prospective cohort study was conducted among 80 residents. KDT was performed at the beginning and end of an overnight call shift for the residents in the experimental group. A control group was tested at the beginning of 2 consecutive day shifts. Estimates of hours of sleep, Karolinska Sleepiness Scale (KSS)(1 = extremely alert, 9 = extremely sleepy), and time and accuracy of KDT were recorded., Results: 42 residents were tested before and after overnight call shifts and 38 served as controls. Change in test time differed between the groups, with the experimental group performing 0.54(SD = 4.0) seconds slower after their night on call and the control group performing 2.32(SD = 3.0) seconds faster on the second day, p < 0.001. This difference was larger in surgical compared to medical residents., Conclusions: Sleep deprivation was inversely correlated with neurocognitive performance as measured by KDT, with more effect on surgical than medical residents. Further research could investigate whether this test could help determine fatigue level and ability to continue working after a long shift., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objective: To investigate whether Posterior Dominant Rhythm (PDR) can be reliably assessed in sleep-EEG recordings and to investigate the diagnostic yield of standard-wake and sleep-recordings., Methods: EEG recordings of 303 consecutive patients aged 18-88 years were analyzed. All patients had both standard-wake and sleep-recordings, including patients who had abnormal standard recordings. Melatonin was used in 6% of sleep EEGs, and sleep deprivation in 94%. The mean duration of sleep was 41 min. We measured the PDR frequency in standard and sleep-recordings, both before and after sleep. We compared the diagnostic yield of standard-wake and sleep EEG recordings., Results: Compared to standard EEG, sleep-recordings showed a significantly lower PDR frequency, both when measured before and after sleep (p < 0.001). One-hundred-fifty-six patients (51%) had normal standard recordings, and 35 of them (22%) had abnormal findings in the sleep-recording. One-hundred-forty-seven patients had abnormal standard recordings and in 16 of them (11%) these abnormalities were not present in sleep-recording., Conclusions: PDR is significantly slower in the wake periods of sleep-recordings, compared to standard wake recordings., Significance: Sleep and standard wake recordings are complementary., (Copyright © 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Background and Aims: Habitual short nightly sleep duration is associated with increased atherosclerotic cardiovascular disease risk and morbidity. Vascular endothelial dysfunction represents an important mechanism that may underlie this heightened cardiovascular risk. Impaired endothelium-dependent vasodilation, particularly NO-mediated vasodilation, contributes to the development and progression of atherosclerotic vascular disease and acute vascular events. We tested the hypothesis that chronic insufficient sleep is associated with impaired NO-mediated endothelium-dependent vasodilation in middle-aged adults., Methods: Thirty adult men were studied: 15 with normal nightly sleep duration (age: 58 ± 2 y; sleep duration: 7.7 ± 0.2 h/night) and 15 with short nightly sleep duration (55 ± 2 y; 6.1 ± 0.2 h/night). Forearm blood flow (FBF) responses to intra-arterial infusion of acetylcholine, in the absence and presence of the endothelial NO synthase inhibitor N G -monomethyl-L-arginine (L-NMMA), as well as responses to sodium nitroprusside, were determined by strain-gauge venous occlusion plethysmography., Results: The FBF response to acetylcholine was lower (∼20%; p<0.05) in the short sleep duration group (from 4.6 ± 0.3 to 11.7 ± 1.0 ml/100 ml tissue/min) compared with normal sleep duration group (from 4.4 ± 0.3 to 14.5 ± 0.5 ml/100 ml tissue/min). L-NMMA significantly reduced the FBF response to acetylcholine in the normal sleep duration group (∼40%), but not the short sleep duration group. There were no group differences in the vasodilator response to sodium nitroprusside., Conclusions: These data indicate that short nightly sleep duration is associated with endothelial-dependent vasodilator dysfunction due, in part, to diminished NO bioavailability. Impaired NO-mediated endothelium-dependent vasodilation may contribute to the increased cardiovascular risk with insufficient sleep., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Sleep is essential for children's learning, memory processes, school performance, and general well-being. The prevalence of sleepiness in children is approximately 4%. Reductions of sleep duration have daytime consequences, including sleepiness, behavior problems, cognitive deficits, poor school performance, inflammation, and metabolic dysfunction. Chronic pain, movement disorders, and sleep-disordered breathing also may lead to daytime somnolence, inattention, hyperactivity, oppositional behaviors, and mood dysregulation. Parent-report questionnaires are useful tools to assess subjective sleepiness in children. Sleepiness in children may be secondary to a sleep problem, such as narcolepsy, central hypersomnia, Kleine-Levin disease, or circadian rhythm disorder., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The orexin system has been investigated in patients affected by mild cognitive impairment (MCI) due to Alzheimer's disease (AD) by measuring orexin-A concentrations in the cerebrospinal fluid (CSF), and correlated to subjective and objective sleep parameters, quantified by questionnaires and polysomnography, respectively. Twenty drug-naïve patients with MCI due to AD were studied and compared with a population of 26 age and/or sex matched controls, divided into subgroups on the basis of the Pittsburgh Sleep Quality Index (PSQI) score. Increased CSF-orexin levels were detected in patients with MCI due to AD in comparison with controls (p < 0.05). In particular, CSF-orexin concentrations were higher in MCI patients suffering from sleep complaints (PSQI ≥5, n = 10) compared with MCI patients with a regular sleep-wake cycle (PSQI <5, n = 10, p < 0.001) and compared with both control groups (with sleep complaints, PSQI ≥5, n = 11, p < 0.001; without sleep complaints, PSQI <5, n = 15, p < 0.001). Moreover, REM sleep was reduced in MCI patients compared with controls (p < 0.01), and had a negative correlation coupled with a reciprocal influence at the multiple regression analysis with CSF-orexin levels (R = -0.65; β = -8.90). REM sleep disruption and sleep fragmentation are related to higher CSF-orexin levels in patients with MCI due to AD, thus suggesting that the orexin system may be involved even in the earliest stages of AD, resulting in prolonged sleep latency, reduced sleep efficiency, and REM sleep impairment., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objective: Changes in slow waves during non-rapid eye movement (NREM) sleep in response to acute total sleep deprivation are well-established measures of sleep homeostasis. This investigation utilized high-density electroencephalography (hdEEG) to examine topographic changes in slow waves during repeated partial sleep deprivation., Methods: Twenty-four participants underwent a 6-day sleep restriction protocol. Spectral and period-amplitude analyses of sleep hdEEG data were used to examine changes in slow wave energy, count, amplitude, and slope relative to baseline., Results: Changes in slow wave energy were dependent on the quantity of NREM sleep utilized for analysis, with widespread increases during sleep restriction and recovery when comparing data from the first portion of the sleep period, but restricted to recovery sleep if the entire sleep episode was considered. Period-amplitude analysis was less dependent on the quantity of NREM sleep utilized, and demonstrated topographic changes in the count, amplitude, and distribution of slow waves, with frontal increases in slow wave amplitude, numbers of high-amplitude waves, and amplitude/slopes of low amplitude waves resulting from partial sleep deprivation., Conclusions: Topographic changes in slow waves occur across the course of partial sleep restriction and recovery., Significance: These results demonstrate a homeostatic response to partial sleep loss in humans., (Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Objectives: To improve identification of obstructive sleep apnea (OSA) patients at risk of driving impairment, this study explored predictors of driving performance impairment in untreated OSA patients using clinical PSG metrics, sleepiness questionnaires and quantitative EEG markers from routine sleep studies., Methods: Seventy-six OSA patients completed sleepiness questionnaires and driving simulator tests in the evening of their diagnostic sleep study. All sleep EEGs were subjected to quantitative power spectral analysis. Correlation and multivariate linear regression were used to identify the strongest predictors of driving simulator performance., Results: Absolute EEG spectral power across all frequencies (0.5-32 Hz) throughout the entire sleep period and separately in REM and NREM sleep, (r range 0.239-0.473, all p<0.05), as well as sleep onset latency (r=0.273, p<0.017) positively correlated with driving simulator steering deviation. Regression models revealed that amongst clinical and qEEG variables, the significant predictors of worse steering deviation were greater total EEG power during NREM and REM sleep, greater beta EEG power in NREM and greater delta EEG power in REM (range of variance explained 5-17%, t range 2.29-4.0, all p<0.05) and sleep onset latency (range of variance explained 4-9%, t range 2.15-2.5, all p<0.05)., Conclusions: In OSA patients, increased EEG power, especially in the faster frequency (beta) range during NREM sleep and slower frequency (delta) range in REM sleep were associated with worse driving performance, while no relationships were observed with clinical metrics e.g. apnea, arousal or oxygen indices., Significance: Quantitative EEG analysis in OSA may provide useful markers of driving impairment risk. Future studies are necessary to confirm these findings and assess the clinical significance of quantitative EEG as predictors of driving impairment in OSA., (Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Background: Neuroimaging studies suggest that acute sleep deprivation can lead to adaptations, such as compensatory recruitment of cerebral structures, to maintain cognitive performance despite sleep loss. However, the understanding of the neurochemical alterations related to these adaptations remains incomplete., Objective: Investigate BDNF levels, cognitive performance and their relations in healthy subjects after acute sleep deprivation., Methods: Nineteen sleep deprived (22.11±3.21years) and twenty control (25.10±4.42years) subjects completed depression, anxiety and sleep quality questionnaires. Sleep deprived group spent a full night awake performing different playful activities to keep themselves from sleeping. Attention, response inhibition capacity and working memory (prefrontal cortex-dependent) were assessed with Stroop and Digit Span tests. Declarative memory (hippocampus-dependent) was assessed with Logical Memory test. Serum BDNF was measured by sandwich ELISA. Data were analyzed with independent samples T-test, ANOVA, ANCOVA and curve estimation regressions. p<0.05 was deemed statistically significant., Results: The sleep deprived group showed higher BDNF levels and normal performance on attention, response inhibition capacity and working memory. However, declarative memory was impaired. A sigmoidal relation between BDNF and Stroop Test scores was found., Conclusions: Increased BDNF could be related, at least in part, to the maintenance of normal prefrontal cognitive functions after sleep deprivation. This potential relation should be further investigated., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Objective: Sleep restriction seems to change our experience of pain and reduce laser evoked potential (LEP) amplitudes. However, although LEP-habituation abnormalities have been described in painful conditions with comorbid sleep impairment, no study has previously measured the effect of sleep restriction on LEP-habituation, pain thresholds, and suprathreshold pain., Method: Sixteen males and seventeen females (aged 18-31years) were randomly assigned to either two nights of delayed bedtime and four hours sleep (partial sleep deprivation) or nine hours sleep. The study subjects slept at home, and the sleep was measured with actigraphy both nights and polysomnography the last night. LEP, thermal thresholds and suprathreshold pain ratings were obtained the day before and the day after intervention. The investigator was blinded. ANOVA was used to evaluate the interaction between sleep restriction and day for each pain-related variable., Results: LEP-amplitude decreased after sleep restriction (interaction p=0.02) compared to subjects randomized to nine hours sleep. LEP-habituation was similar in both groups. Thenar cold pain threshold decreased after sleep restriction (interaction p=0.009). Supra-threshold heat pain rating increased temporarily 10s after stimulus onset after sleep restriction (interaction p=0.01), while it did not change after nine hours sleep., Conclusion: Sleep restriction reduced the CNS response to pain, while some of the subjective pain measures indicated hyperalgesia., Significance: Since LEP-amplitude is known to reflect both CNS-pain-specific processing and cognitive attentive processing, our results suggest that hyperalgesia after sleep restriction might partly be caused by a reduction in cortical cognitive or perceptual mechanisms, rather than sensory amplification., (Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Objective: The deleterious neurocognitive effects of laboratory-controlled short-term sleep deprivation are well-known. The present study investigated neurocognitive changes arising from chronic sleep restriction outside the laboratory., Methods: Sleep patterns of 24 undergraduates were tracked via actigraphy across a 15-week semester. At the semester beginning, at a midpoint, and a week before finals, students performed the Psychomotor Vigilance Test (PVT) and cortical arousal was measured via event-related potentials (ERP) and resting state electroencephalography (EEG)., Results: Average daily sleep decreased between Session 1 and Sessions 2 and 3. Calculated circadian rhythm measures indicated nighttime movement increased and sleep quality decreased from Sessions 1 and 2 to Session 3. Parallel to the sleep/activity measures, PVT reaction time increased between Session 1 and Sessions 2 and 3 and resting state alpha EEG reactivity magnitude and PVT-evoked P3 ERP amplitude decreased between Session 1 and Sessions 2 and 3. Cross-sectional regressions showed PVT reaction time was negatively associated with average daily sleep, alpha reactivity, and P3 changes; sleep/circadian measures were associated with alpha reactivity and/or P3 changes., Conclusions: Small, but persistent sleep deficits reduced cortical arousal and impaired vigilant attention., Significance: Chronic sleep restriction impacts neurocognition in a manner similar to laboratory controlled sleep deprivation., (Copyright © 2014 International Federation of Clinical Neurophysiology. All rights reserved.)

Background: Changes of cortical excitability after sleep deprivation (SD) in humans have been investigated mostly in motor cortex, while there is little empirical evidence concerning somatosensory cortex, and its plastic changes across SD., Objective: To assess excitability of primary somatosensory cortex (S1) and EEG voltage topographical characteristics associated with somatosensory evoked potentials (SEPs) during SD., Methods: Across 41 h of SD, 16 healthy subjects participated in 4 experimental sessions (11.00 a.m. and 11.00 p.m. of the 1st and 2nd day) with: a) subjective sleepiness ratings; b) EEG recordings; c) SEPs recordings; d) behavioral vigilance responses., Results: A clear enhancement of cortical excitability after SD was indexed by: (a) an amplitude increase of different SEPs component in S1; (b) higher voltage in occipital (around 35-43 ms) and fronto-central areas (around 47-62 ms). Circadian fluctuations did not affect cortical excitability. Voltage changes in S1 were strongly related with post-SD fluctuations of subjective and behavioral sleepiness., Conclusions: Sleep may have a role in keeping cortical excitability at optimal (namely below potentially dangerous) levels for the human brain, rebalancing progressive changes in cortical responsiveness to incoming inputs occurred during time spent awake. On the other hand, higher level of cortical responsiveness after sleep loss may be one of the mechanisms accounting for post-SD alterations in vigilance and behavior., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Purpose: Young adults regularly experience restricted sleep due to a range of social, educational, and vocational commitments. Evidence suggests that extended periods of sleep deprivation negatively impact affective and inhibitory control mechanisms leading to behavioral consequences such as increased emotional reactivity and impulsive behavior. It is less clear whether acute periods of restricted sleep produce the same behavioral consequences., Methods: Nineteen young adults (m = 8 and f = 12) with habitual late bedtime (after 22:30 h) and wake time (after 06:30 h) completed a range of objective and subjective measures assessing sleepiness (psychomotor vigilance task and Karolinska sleepiness scale), inhibitory control (emotional go/no-go task and a balloon analog risk task), and affect (positive and negative affective schedule). Testing was counterbalanced across participants and occurred on two occasions once following restricted sleep and once following habitual sleep 1 week apart., Results: Compared with habitual sleep, sleep restriction produced significantly slower performance on the psychomotor vigilance task and higher subjective ratings of sleepiness on the Karolinska sleepiness scale. Sleep restriction also caused a significant decrease in positive affect but no change in negative affect on the affective schedule. Inhibitory control efficiency was significantly differentiated, with participants showing an increase in risk taking on the balloon analog risk task, but there was no evidence of increased reactivity to negative stimuli on the emotional go/no-go task., Conclusions: Results suggest that even acute periods of sleep loss may cause deficits in affective experiences and increase impulsive and potentially high-risk behavior in young adults., (Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Purposes: The Japanese word "ronin-sei" refers to a student who has failed their university entrance examination and is preparing to re-take the examination in the following year. We aimed to determine how sleep duration is associated with daytime sleepiness or depression in ronin-sei because impaired daytime performance is known to result from sleep deprivation., Methods: The participants in this cross-sectional study were 1075 ronin-sei and 285 university students. Sleepiness and depressive symptoms were assessed using the Epworth Sleepiness Scale (ESS) and the Center for Epidemiologic Studies Depression Scale (CES-D), respectively., Results: Ronin-sei had significantly shorter sleep duration and earlier bed- and rise-times than university students. There was no significant difference in CES-D between the groups; however, the ESS score of university students was significantly higher than that of ronin-sei. Ronin-sei who slept for 5 to <6h had higher ESS scores than those who slept for 6 to <7h. The mean CES-D score in ronin-sei who slept <5h was significantly higher than in those who slept for 5 to <6h, from 6 to <7h, and from 7 to <8h. Ronin-sei who slept for more than 8h also had higher depression scores., Conclusions: Sleep deprivation appears to be common among ronin-sei. Furthermore, a U-shaped relationship was found between sleep duration and depressive symptoms, revealing that ronin-sei who had too little or too much sleep were more likely to exhibit an increase in depressive symptoms., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Objective: To demonstrate that the severity of obstructive sleep apnea (OSA) could be predicted algorithmically by means of recurrence analysis of the sleep-staged electroencephalogram (EEG)., Methods: A randomly selected cohort of 20 sleep-staged patients with OSA (apnea-hypopnea index (AHI) 5-30) was divided into mild and moderate sub-cohorts (AHI 5-15, 16-30, respectively), and the sleep EEG (C3) was analyzed using analysis of brain recurrence (ABR) (LSU cohort). Twenty distinct but related markers for sleep depth and fragmentation were computed from four ABR variables, and a marker function capable of classifying each patient into one of the two sub-cohorts was determined by linear discriminant analysis. Classification accuracy of individual patients was evaluated using area under the receiver operator characteristics curve (AUROC). As a control procedure, 20 additional sleep-staged patients with OSA whose polysomnographic data was obtained from an independent database were also evaluated (SHHS cohort)., Results: On average, markers for sleep depth were reduced and those for sleep fragmentation were increased in the patients with moderate OSA, as expected. All patients in both cohorts were correctly classified using as few as 5-6 markers., Significance: The degree of severity of OSA was reflected in objective changes in the sleep EEG. Recurrence analysis of the EEG potentially has uses beyond identification of the degree of OSA., (Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Previous studies of the reproducibility of blood pressure (BP) dipping have yielded inconsistent results. Few have examined factors that may influence day-to-day differences in dipping. Ambulatory BP monitoring was performed on three occasions, approximately 1 week apart, in 115 untreated adult subjects with elevated clinic BPs. The mean ± standard deviation BP dip was 18 ± 7/15 ± 5 mm Hg (sleep/awake BP ratio = 0.87 ± 0.05/0.82 ± 0.06), with a median (interquartile range) day-to-day variation of 5.2 (3.1-8.1)/4.3 (2.8-5.6) mm Hg. There was no decrease in variability with successive measurements. The reproducibility coefficient (5.6 [95% confidence interval, 5.1-6.1] mm Hg) was greater and the intraclass correlation coefficient (0.53 [95% confidence interval, 0.42-0.63]) was smaller for the systolic dip than for 24-hour or awake systolic BPs, suggesting greater day-to-day variability in dipping. Variability in systolic dipping was greater in subjects with higher awake BP, but was not related to age, gender, race, or body mass index. Within individuals, day-to-day variations in dipping were related to variations in the fragmentation index (P < .001), a measure of sleep quality. Although mean 24-hour and awake BPs were relatively stable over repeated monitoring days, our study confirms substantial variability in BP dipping. Day-to-day differences in dipping are related to sleep quality., (Copyright © 2013 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.)

Sleep deprivation can result in significant impairments in daytime neurobehavioral functioning in children. Neural substrates impacted by sleep deprivation include the prefrontal cortex, basal ganglia and amygdala and result in difficulties with executive functioning, reward anticipation and emotional reactivity respectively. In everyday life, such difficulties contribute to academic struggles, challenging behaviors and public health concerns of substance abuse and suicidality. In this article, we aim to review 1) core neural structures impacted by sleep deprivation; 2) neurobehavioral problems associated with sleep deprivation; 3) specific mechanisms that may explain the relationship between sleep disturbances and neurobehavioral dysfunction; and 4) sleep problems reported in common neurodevelopmental disorders including attention deficit hyperactivity disorder (ADHD) and autistic spectrum disorders (ASDs)., (Published by Elsevier B.V.)

We determined whether alterations in heart rate dynamics during sleep in patients with chronic fatigue syndrome (CFS) differed from controls and/or correlated with changes of sleepiness before and after a night in the sleep laboratory. We compared beat-to-beat RR intervals (RRI) during nocturnal sleep, sleep structure, and subjective scores on visual analog scale for sleepiness in 18 CFS patients with 19 healthy controls aged 25-55 after excluding subjects with sleep disorders. A short-term fractal scaling exponent (α1) of RRI dynamics, analyzed by the detrended fluctuation analysis (DFA) method, was assessed after stratifying patients into those who reported more or less sleepiness after the night's sleep (a.m. sleepier or a.m. less sleepy, respectively). Patients in the a.m. sleepier group showed significantly (p<0.05) higher fractal scaling index α1 during non-rapid eye movement (non-REM) sleep (Stages 1, 2, and 3 sleep) than healthy controls, although standard polysomnographic measures did not differ between the groups. The fractal scaling index α1 during non-REM sleep was significantly (p<0.05) higher than that during awake periods after sleep onset for healthy controls and patients in the a.m. less sleepy group, but did not differ between sleep stages for patients in the a.m. sleepier group. For patients, changes in self-reported sleepiness before and after the night correlated positively with the fractal scaling index α1 during non-REM sleep (p<0.05). These results suggest that RRI dynamics or autonomic nervous system activity during non-REM sleep might be associated with disrupted sleep in patients with CFS., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Sleep deprivation is highly prevalent in the general population and related to lifestyle in industrialized countries. There has been an increase in this reduction of sleep for half a century and adolescents are particularly affected. Given the magnitude of this sleep restriction, it seems important to focus its mechanisms and its neurocognitive, endocrine, metabolic, weight, psychological and school consequences on adolescents. This sleep deprivation is described and the solutions that can be proposed to adolescents and their family or school environment to increase sleep duration and decrease the negative consequences of their current sleep deprivation are reviewed., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

Background: Sleep complaints are common among patients with traumatic brain injury. Evaluation of this population is confounded by polypharmacy and comorbid disease, with few studies addressing combat-related injuries. The aim of this study was to assess the prevalence of sleep disorders among soldiers who sustained combat-related traumatic brain injury., Methods: The study design was a retrospective review of soldiers returning from combat with mild to moderate traumatic brain injury. All underwent comprehensive sleep evaluations. We determined the prevalence of sleep complaints and disorders in this population and assessed demographics, mechanism of injury, medication use, comorbid psychiatric disease, and polysomnographic findings to identify variables that correlated with the development of specific sleep disorders., Results: Of 116 consecutive patients, 96.6% were men (mean age, 31.1 ± 9.8 years; mean BMI, 27.8 ± 4.1 kg/m²), and 29.5% and 70.5% sustained blunt and blast injuries, respectively. Nearly all (97.4%) reported sleep complaints. Hypersomnia and sleep fragmentation were reported in 85.2% and 54.3%, respectively. Obstructive sleep apnea syndrome (OSAS) was found in 34.5%, and 55.2% had insomnia. Patients with blast injuries developed more anxiety (50.6% vs 20.0%, P = .002) and insomnia (63% vs 40%, P = .02), whereas patients with blunt trauma had significantly more OSAS (54.3% vs 25.9%, P = .003). In multivariate analysis, blunt trauma was a significant predictor of OSAS (OR, 3.09; 95% CI, 1.02-9.38; P = .047)., Conclusions: Sleep disruption is common following traumatic brain injury, and the majority of patients develop a chronic sleep disorder. It appears that sleep disturbances may be influenced by the mechanism of injury in those with combat-related traumatic brain injury, with blunt injury potentially predicting the development of OSAS.

Purpose: To characterize sleep patterns and predictors of poor sleep quality in a large population of college students. This study extends the 2006 National Sleep Foundation examination of sleep in early adolescence by examining sleep in older adolescents., Method: One thousand one hundred twenty-five students aged 17 to 24 years from an urban Midwestern university completed a cross-sectional online survey about sleep habits that included the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale, the Horne-Ostberg Morningness-Eveningness Scale, the Profile of Mood States, the Subjective Units of Distress Scale, and questions about academic performance, physical health, and psychoactive drug use., Results: Students reported disturbed sleep; over 60% were categorized as poor-quality sleepers by the PSQI, bedtimes and risetimes were delayed during weekends, and students reported frequently taking prescription, over the counter, and recreational psychoactive drugs to alter sleep/wakefulness. Students classified as poor-quality sleepers reported significantly more problems with physical and psychological health than did good-quality sleepers. Students overwhelmingly stated that emotional and academic stress negatively impacted sleep. Multiple regression analyses revealed that tension and stress accounted for 24% of the variance in the PSQI score, whereas exercise, alcohol and caffeine consumption, and consistency of sleep schedule were not significant predictors of sleep quality., Conclusions: These results demonstrate that insufficient sleep and irregular sleep-wake patterns, which have been extensively documented in younger adolescents, are also present at alarming levels in the college student population. Given the close relationships between sleep quality and physical and mental health, intervention programs for sleep disturbance in this population should be considered., (Copyright 2010 Society for Adolescent Medicine. Published by Elsevier Inc. All rights reserved.)

Objective: To compare the new American Academy of Sleep Medicine (AASM) criteria for scoring sleep with the previous Rechtschaffen and Kales (R&K) criteria in a cohort of children with primary snoring, obstructive sleep apnea syndrome (OSAS) and normal controls., Methods: Polysomnography was performed in 26 consecutive children with primary snoring (13 males, mean age 6.2 years, SD 3.2), in 39 with OSAS (24 males, mean age 6.1 years, SD 3.0), and in 10 age-matched normal controls., Results: Compared to the other groups, OSAS children showed a lower percentage of slow-wave sleep, using both R&K and AASM criteria; they also showed a higher percentage of stage shifts, and N1, using the AASM criteria. Children with primary snoring showed a higher percentage of N1, compared to controls., Conclusions: These results indicate that the use of the new AASM criteria seem to disclose more differences in sleep parameters than the R&K rules in children with OSAS., Significance: The AASM criteria seem to disclose a high degree of sleep fragmentation in children with OSAS, mostly related to the repeated occurrence of N1., (Copyright 2009 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Objective: To explore women's levels of childbirth fear, sleep deprivation, anxiety, and fatigue and their relationships during the third trimester of pregnancy., Design: A cross-sectional descriptive survey of a community sample., Participants: Six hundred and fifty English-speaking nulliparous and multiparous women, 17 to 46 years of age and between 35 and 39 weeks gestation, with uncomplicated pregnancies., Methods: Wijma Delivery Expectancy/Experience Questionnaire, Spielberger State Anxiety Inventory, Mindell's Sleep Questionnaire, and the Multidimensional Assessment of Fatigue Questionnaire., Results: Twenty-five percent of women reported high levels of childbirth fear and 20.6% reported sleeping less than 6 hours per night. Childbirth fear, fatigue, sleep deprivation, and anxiety were positively correlated. Fewer women attending midwives reported severe fear of childbirth than those attending obstetricians. Women with high childbirth fear were more likely to have more daily stressors, anxiety, and fatigue, as well as less help. Higher levels of anxiety predicted higher levels of childbirth fear among women., Conclusion: One fourth of women reported high childbirth fear. Women's fear of childbirth was related to fatigue, available help, stressors, and anxiety. Fear of childbirth appears to be part of a complex picture of women's emotional experiences during pregnancy.

Objective: To determine the current knowledge of postpartum women's sleep patterns, sleep disturbances, consequences of sleep disturbances, and known strategies for prevention in order to provide best practice recommendations for health care providers., Data Sources: A literature search from 1969 through February 2008 was conducted using the CINHL, Index of Allied Health Literature, Ovid, PsycINFO, and PubMed electronic databases in addition to reference lists from selected articles and other key references. Search terms included sleep, postpartum, sleep deprivation, and sleep disturbance., Study Selection: A critical review of all relevant articles from the data sources was conducted with attention to the needs of postpartum women's sleep and implications for health care providers., Data Extraction: Literature was reviewed and organized into groups with similar characteristics., Data Synthesis: An integrative review of the literature summarized the current state of research related to sleep alterations in postpartum women., Conclusions: Postpartum women experience altered sleep patterns that may lead to sleep disturbances. The most common reasons for sleep disturbances are related to newborn sleep and feeding patterns. Although present, the relationships among sleep disturbance, fatigue, and depression in postpartum women lack clarity due to their ambiguous definitions and the variety of the studies conducted. Providers should encourage prenatal education that assists the couple in developing strategies for decreasing postpartum sleep deprivation. Alterations of in-hospital care and home care should be incorporated to improve the new family's sleep patterns.

Objective: To examine patterns of postpartum parental sleep and levels of fatigue at 2, 12, and 20 weeks following hospital discharge of newborn twins., Design: Descriptive longitudinal pilot study., Setting: Recruitment from 2 hospital postpartum units. Data collected in parents' homes., Participants: Eight primiparous parents caring for twins delivered at 33 to 38 weeks gestation., Methods: Home visits to deliver and retrieve study equipment: wrist actigraphy and sleep diaries to measure sleep, standardized instrument to measure fatigue, and an investigator-developed form to measure demographics and related variables., Results: Fathers had significantly less night sleep (5.4 hours) and less 24 hour sleep (5.8 hours) than mothers (6.2 and 6.9 hours, respectively) at 2 weeks after twins were discharged. Sleep efficiency increased significantly over time in a linear fashion for both parents. Morning and evening fatigue levels were not significantly different between parents and remained constant over time., Conclusion: Pilot data suggest that mothers and especially fathers of twins experience sleep disturbances after discharge of their twins. Further study is needed to more fully describe the evolution of sleep patterns and clarify factors that influence sleep in parents of twins.

Objective: To describe sleep characteristics in high-risk antepartum inpatients., Design: Prospective descriptive design., Setting: Tertiary hospital in southern California., Participants: A convenience sample of 39 antepartum women., Methods: Data were collected from participants' medical records, questionnaires (General Sleep Disturbance Scale), actigraphy on days 3 to 4 after admission, and a sleep diary that included reasons for awakening and morning and evening fatigue ratings., Results: Week gestation ranged from 24 to 35 weeks. Sleep time varied from 310 to 492 minutes and averaged 6.7 hours/night. The women were awakened 9 to 32 times/night and averaged 18 awakenings. They napped an average of 124 minutes throughout the day. Women averaged 3.9 on the General Sleep Disturbance Scale when retrospectively considering 7 days before hospitalization and scored 4.1 when considering the current 3 days of hospitalization. In the diary, most rated their sleep quality as Fairly Good or Very Good (62%-71%), but 29% said Very Bad on night 2, and 38% said Very Bad on night 3., Conclusion: Frequent interruptions during the night do not allow for mothers to receive the restorative sleep they need.

Background: Infants exposed prenatally to alcohol are at increased risk for poor neurodevelopmental outcome including Sudden Infant Death Syndrome., Aim: To examine the relationship between prenatal alcohol exposure, sleep, arousal and sleep-related spontaneous motor movements in early infancy., Study Design: Low-income women (N=13) were interviewed regarding pre- and pregnancy rates of alcohol, cigarette smoking and other substance use in the perinatal period. Infants were examined in a laboratory nap study using EEG, videography and actigraphy at 6-8 weeks of age. Estimates of maternal pre- and pregnancy alcohol use were used to divide infants into high vs. low maternal alcohol use groups., Subjects: Mother-infant dyads recruited from a family practice clinic., Outcome Measures: Sleep-related spontaneous movements, behavioral state, and maternal assessments of infant alertness and irritability., Results: Pre-pregnancy rates of alcohol consumption including binge drinking correlated with maternal report of poor infant alertness, and increased irritability. High maternal exposure groups showed increased sleep fragmentation, e.g., frequency and duration of wakefulness following sleep onset and decreased active sleep. Bout analysis of the temporal structure of sleep-related spontaneous movements showed significantly reduced bout duration associated with high maternal alcohol use., Conclusion: These results present evidence that prenatal alcohol exposure disrupts postnatal sleep organization and suppresses spontaneous movements during sleep, and increased sleep fragmentation promotes sleep deprivation. Results are consistent with the SIDS model of chronic sleep debt and suggest that attenuated sleep-related movements should be examined as an important modulator of cardiorespiratory functions during sleep in high-risk groups.

The aim of this cross-sectional study was to investigate relationships among women's body attitudes, physical symptoms, self-esteem, depression, and sleep quality during pregnancy. Pregnant women (N=215) at 15-25 weeks gestation completed a questionnaire including four body image subscales assessing self-reported feeling fat, attractiveness, strength/fitness, and salience of weight and shape. Women reported on 29 pregnancy-related physical complaints, and completed the Beck Depression Inventory, Rosenberg Self-esteem Scale, and Pittsburgh Sleep Quality Index. In regressions, controlling for retrospective reports of body image, more frequent and intense physical symptoms were related to viewing the self as less strong/fit, and to poorer sleep quality and more depressive symptoms. In a multi-factorial model extending previous research, paths were found from sleep quality to depressive symptoms to self-esteem; self-esteem was found to be a mediator associated with lower scores on feeling fat and salience of weight and shape, and on higher perceived attractiveness.

Objective: The objective of this study is the development and evaluation of efficient neurophysiological signal statistics, which may assess the driver's alertness level and serve as potential indicators of sleepiness in the design of an on-board countermeasure system., Methods: Multichannel EEG, EOG, EMG, and ECG were recorded from sleep-deprived subjects exposed to real field driving conditions. A number of severe driving errors occurred during the experiments. The analysis was performed in two main dimensions: the macroscopic analysis that estimates the on-going temporal evolution of physiological measurements during the driving task, and the microscopic event analysis that focuses on the physiological measurements' alterations just before, during, and after the driving errors. Two independent neurophysiologists visually interpreted the measurements. The EEG data were analyzed by using both linear and non-linear analysis tools., Results: We observed the occurrence of brief paroxysmal bursts of alpha activity and an increased synchrony among EEG channels before the driving errors. The alpha relative band ratio (RBR) significantly increased, and the Cross Approximate Entropy that quantifies the synchrony among channels also significantly decreased before the driving errors. Quantitative EEG analysis revealed significant variations of RBR by driving time in the frequency bands of delta, alpha, beta, and gamma. Most of the estimated EEG statistics, such as the Shannon Entropy, Kullback-Leibler Entropy, Coherence, and Cross-Approximate Entropy, were significantly affected by driving time. We also observed an alteration of eyes blinking duration by increased driving time and a significant increase of eye blinks' number and duration before driving errors., Conclusions: EEG and EOG are promising neurophysiological indicators of driver sleepiness and have the potential of monitoring sleepiness in occupational settings incorporated in a sleepiness countermeasure device., Significance: The occurrence of brief paroxysmal bursts of alpha activity before severe driving errors is described in detail for the first time. Clear evidence is presented that eye-blinking statistics are sensitive to the driver's sleepiness and should be considered in the design of an efficient and driver-friendly sleepiness detection countermeasure device.

Nearly all people, whether they consider themselves sleep deprived or not, can initially obtain extra sleep. However, as accumulating extra sleep reduces carryover sleep debt, a point is reached where it is no longer possible to obtain extra sleep. If there were a practical method to make a precise measurement of a person's daily sleep requirement, it may be possible to show that most individuals are carrying a very large sleep debt. Several observations and studies demonstrate that almost everyone is sleep deprived and carries some amount of sleep debt. How long such an indebtedness will persist without change if no extra sleep is obtained is not known.

Objective: The purpose of the present study was to investigate the effects of total sleep deprivation (TSD) on brain functions with an identification procedure for strongly interactive brain regions, relying on functional cluster (FC) analysis in multichannel electroencephalogram (EEG) data., Methods: EEGs from 16 electrodes in 18 healthy, right-handed, young male volunteers were recorded before TSD (after normal sleep) and after 24 h of experimentally induced sleep deprivation. We estimated cluster index to characterize joint interactions among many brain regions in order to determine if a particular FC is present or not, and if so, its anatomy., Results: As a result, we confirmed the presence of FC and found different FC patterns in both before and after TSD. The C3 and F7 locations were outside the cluster under the TSD condition, but belonged to the cluster with C4 and F8 before the TSD condition, and the F3/F4, and O1 locations were new entries to the functional cluster during sustained wakefulness., Conclusions: These results indicate that the neuronal activities of the C3 and F7 location are functionally unrelated, whereas the F3/F4 locations are functionally involved with the C4, F8, and O1 locations after 24 h TSD. Our results suggest that FC changes with elapsed awake time and reflects the change of brain function due to TSD., Significance: This paper shows the existence of FC both before and after TSD, and the anatomy of each FC is different. So FC analysis would be a potential tool to investigate the simultaneous neuronal activity of human EEGs.

Our aim was to determine if less expensive interictal indices can predict which epilepsy patients may benefit from the more expensive comprehensive pre-surgical evaluation. Surgical treatment was determined based on the results of a comprehensive inpatient continuous video-EEG monitoring. This evaluation included three interictal tests, which were reviewed retrospectively-2 hour-sleep-deprived electroencephalogram (SDEEG), magnetic resonance imaging (MRI), and positron emission tomography (PET). Sixty-nine patients were evaluated with 35 patients having focal resection (33 temporal, two frontal). When two or more interictal tests were positive, 77% (27 /35) went to surgery, but when one test was positive 23% (8 /34) had surgery. When all tests were negative, only a single patient (1 /13 or 7.7%) had surgery, a frontal resection. The positive predictive value for any single interictal test was 68%, while it was higher for any combination of two positive tests (77-83%). PET was the most sensitive (0.86) single interictal test, compared to SDEEG (0.66) and MRI (0.66). The odds ratio for predicting surgical treatment for a positive PET, SDEEG, or MRI was 8.57, 4.01, and 4.01, respectively. MRI was three and PET was six times the cost of a SDEEG. The combination of SDEEG and MRI had the best cost/PPV ratio. Seventy-nine percent (11 /14) of the patients with three positive tests were seizure free following focal resection compared to 43% (9 /21) when less than three tests were positive ( P