iSleepFirst: burnout, fatigue, and wearable-tracked sleep deprivation among residents staffing the medical intensive care unit.

PURPOSE: This study aimed to evaluate the relationship between sleep, burnout, and psychomotor vigilance in residents working in the medical intensive care unit (ICU). METHODS: A prospective cohort study of residents was implemented during a consecutive 4-week. Residents were recruited to wear a sleep tracker for 2 weeks before and 2 weeks during their medical ICU rotation. Data collected included wearable-tracked sleep minutes, Oldenburg burnout inventory (OBI) score, Epworth sleepiness scale (ESS), psychomotor vigilance testing, and American Academy of Sleep Medicine sleep diary. The primary outcome was sleep duration tracked by the wearable. The secondary outcomes were burnout, psychomotor vigilance (PVT), and perceived sleepiness. RESULTS: A total of 40 residents completed the study. The age range was 26-34 years with 19 males. Total sleep minutes measured by the wearable decreased from 402 min (95% CI: 377-427) before ICU to 389 (95% CI: 360-418) during ICU (p < 0.05). Residents overestimated sleep, logging 464 min (95% CI: 452-476) before and 442 (95% CI: 430-454) during ICU. ESS scores increased from 5.93 (95% CI: 4.89, 7.07) to 8.33 (95% CI: 7.09,9.58) during ICU (p < 0.001). OBI scores increased from 34.5 (95% CI: 32.9-36.2) to 42.8 (95% CI: 40.7-45.0) (p < 0.001). PVT scores worsened with increased reaction time while on ICU rotation (348.5 ms pre-ICU, 370.9 ms post-ICU, p < 0.001). CONCLUSIONS: Resident ICU rotations are associated with decreased objective sleep and self-reported sleep. Residents overestimate sleep duration. Burnout and sleepiness increase and associated PVT scores worsen while working in the ICU. Institutions should ensure resident sleep and wellness checks during ICU rotation.

Predictors of psychological distress and sleep deprivation in caregivers of stroke survivors.

BACKGROUND: Caregivers for stroke survivors (CSS) suffer from long hours of care, limited support, and financial difficulties, which often affect their mental health. OBJECTIVES: This study sought to determine the factors affecting psychological distress and sleep duration among CSS. METHODS: We analyzed cross-sectional data from the 2013 Comprehensive Survey of the Living Conditions for Stroke Survivors and CSS. Linked data from 841 pairs of stroke survivors and CSS were extracted. Kessler's Psychological Distress scale (K6) was used to evaluate psychological distress. CSS who slept less than 5 hours per day were classified as having short sleep duration. Factors predictive of psychological distress and short sleep duration were evaluated using multivariable logistic regression analysis with the forward selection method. RESULTS: The mean (SD) age of the CSS was 65.4 (12.5) years. A total of 5.6% of these caregivers presented with serious psychological distress, and 12.0% were sleep deprived. Serious psychological distress was associated with not having someone to consult with, having subjective symptoms within a few days, and having short sleep duration, while having their own houses reduced the risk of serious psychological distress. Furthermore, short sleep duration was associated with stroke survivors in long-term care levels 4 or 5, not having someone to consult with, participation in sponge baths as part of nursing care activities, and having serious psychological distress. CONCLUSIONS: This nationwide survey identified several risk factors for psychological stress and sleep deprivation among CSS and suggests the need for multidimensional approaches to reduce their distress.

The Effect of Night Float Rotation on Resident Sleep, Activity, and Well-Being.

BACKGROUND: Night float call systems are becoming increasingly common at training programs with the goal of reducing fatigue related to sleep deprivation and sleep disturbance. Previous studies have shown that trainees obtain less sleep during the night float rotation and have decreased sleep efficiency for several days after the rotation. The impact on physical and emotional well-being has not been documented. METHODS: Twenty-seven anesthesia residents were enrolled in a study using wearable sleep and activity trackers and National Institutes of Health Patient-Reported Outcome Measurement Information System (NIH PROMIS) surveys for sleep disturbance, fatigue, and positive affect to record data the week before ("baseline"), during ("night float"), and 1 week after ("recovery") their night float rotation. Each subject's data during the night float week and recovery week were compared to his or her own baseline week data using a paired, nonparametric analysis. The primary outcome variable was the change in average daily sleep hours during the night float week compared to the baseline week. Average daily rapid eye movement (REM) sleep, daily steps, and NIH PROMIS scores comparing night float and recovery weeks to baseline week were prespecified secondary outcomes. NIH PROMIS scores range from 0 to 100 with 50 as the national mean and more of the construct having a higher score. RESULTS: There was no difference in average daily sleep hours between the night float and the baseline weeks (6.7 [5.9-7.8] vs 6.7 [5.5-7.7] hours, median [interquartile range]; P = .20). Residents had less REM sleep during the night float compared to the baseline weeks (1.1 [0.7-1.5] vs 1.4 [1.1-1.9] hours, P = .002). NIH PROMIS fatigue scores were higher during the night float than the baseline week (58.8 [54.6-65.1] vs 48.6 [46.0-55.1], P = .0004) and did not return to baseline during the recovery week (51.0 [48.6-58.8], P = .029 compared to baseline). Sleep disturbance was not different among the weeks. Positive affect was reduced after night float compared to baseline (39.6 [35.0-43.5] vs 44.8 [40.1-49.6], P = .0009), but returned to baseline during the recovery week (43.6 [39.6-48.2], P = .38). CONCLUSIONS: The residents slept the same number of total hours during their night float week but had less REM sleep, were more fatigued, and had less positive affect. All of these resolved to baseline except fatigue, that was still greater than the baseline week. This methodology appears to robustly capture psychophysiological data that might be useful for quality initiatives.

The Role of Serial Follow-up and Sleep Deprivation Methods in Improving Electroencephalography Diagnostic Yield in a Cohort of Omanis Aged 13 Years and Above: A Clinical Audit Study.

The aim of this audit study was to establish the utility of follow-up and sleep-deprived electroencephalography testing to improve the detection of interictal abnormalities in a tertiary referral center in Oman. As part of our ongoing auditing process, a total of 3010 EEGs were included in this study. All EEGs were routinely performed for Omanis aged 13 years and above, who were referred for possible diagnosis of seizure disorders. Each EEG was performed over an average period of 20-30 minutes. Of the 3010 EEGs, there were 553 follow-up and sleep-deprived EEGs, including initial baseline EEG studies which were analyzed for this study. The total progressive yield of serial follow-up EEGs to detect overall EEG changes was 53.5%, distributed as 8.8%, 11.4%, 0%, and 33.3% for the second, third, fourth, and fifth serial EEG studies, respectively. For the sleep deprivation EEG group, the yield was 6.5% for detecting overall EEG changes compared to the initial EEG studies. A limitation in this study was the small sample size in the subsequent follow-up and sleep deprivation EEGs. In conclusion, we found a minimal contribution of serial follow-up and sleep deprivation methods in improving the EEG abnormality detection in our study. National guidelines and an increase in awareness among physicians are required to increase the benefit of these well-established, yet not optimally utilized EEG methods.

Association between sleep characteristics, ideal cardiovascular health, and systemic inflammation, NHANES 2017-2018.

There is conflicting evidence regarding the associations between sleep deprivation and inflammatory biomarkers indicative of cardiovascular disease risk, such as high-sensitivity C-reactive protein (hsCRP). The association between sleep habits and hsCRP was quantified in a nationally representative sample of adults in the United States and mediation by ideal cardiovascular health metrics was explored. A cross-sectional analysis of cardiovascular disease-free participants aged 20-79 years from the 2017-2018 National Health and Nutrition Examination Survey was conducted. The primary exposures were self-reported sleep duration, sleep debt (difference between the average weekday and weekend sleep duration), and ideal cardiovascular health (11-14 points). The primary outcome was hsCRP (high-risk ≥ 3.0 mg/L). Multivariable robust Poisson models were used to estimate prevalence ratios after multiple imputation. A subgroup analysis of shift workers was also conducted. Of 4027 participants included (mean age 46 years; 52% female; 41% shift workers), the prevalence of sleeping <6 h on weekdays was 9%, with 40% sleeping ≥9 h on weekends. One-quarter had a high (≥2 h) sleep debt, 82% had poor cardiovascular health, and 34% had high-risk hsCRP. There were no significant associations between weekday sleep duration or sleep debt with high-risk hsCRP, even among shift workers. Mediation analysis was not conducted. Ideal cardiovascular health was associated with a lower prevalence of high-risk hsCRP (prevalence ratios, 0.60, 95% CI, 0.48-0.75). The lack of significant associations suggests a complex interrelationship of hsCRP with factors beyond sleep duration. Examination of populations at highest risk of chronic sleep deprivation could help to elucidate the association with systemic inflammation-related outcomes.

Efficacy and safety of electroacupuncture treatment in the prevention of negative moods in healthy young men after 30 h of total sleep deprivation: study protocol for a single-center, single-blind, parallel-arm, randomized clinical trial.

BACKGROUND: Sleep deprivation (SD) among young adults is a major public health concern. In humans, it has adverse effects on mood and results in serious health problems. Faced with SD, persons may take precautionary measures to try and reduce their risk. The aim of this study is to evaluate the efficacy and safety of electroacupuncture (EA) for the prevention of negative moods after SD. In addition, we will do a comparison of the effects of EA on mood after SD at different time points. METHODS: This randomized controlled trial (RCT) will be performed at the First Affiliated Hospital of Changchun University of Chinese Medicine in China. The Standards for Reporting Interventions in Clinical Trials of Acupuncture 2010 will be strictly adhered to. Forty-two healthy male volunteers will be distributed into acupoints electroacupuncture (AE) group, non-acupoints electroacupuncture (NAE) control group, or blank control group. This trial will comprise 1-week baseline (baseline sleep), 1-week preventative treatment, 30-h total sleep deprivation (TSD), and 24-h after waking follow-up period. Participants in the AE group and the NAE control group during the preventative treatment period will be administered with EA treatment once daily for 1 week. Participants in the blank control group will not be administered with any treatment. The primary outcome will be the Profile of Mood States (POMS) Scale. Secondary outcome measures will include changes in the Noldus FaceReader (a tool for automatic analysis of facial expressions) and Positive and Negative Affect Schedule (PANAS) Scale. Total sleep deprivation will be 30 h. During the 30-h TSD period, participants will be subjected to 11 sessions of assessment. Adverse events will be recorded. DISCUSSION: This study is designed to evaluate the efficacy and safety of EA for the prevention of negative moods after SD. The results of this trial will allow us to compare the effects of EA on mood after SD at different time points. Moreover, the findings from this trial will be published in peer-reviewed journals. TRIAL REGISTRATION: Chinese Clinical Trial Registry Chi2000039713 . Registered on 06 November 2020.

Effects of sleep habits on acute myocardial infarction risk and severity of coronary artery disease in Chinese population.

BACKGROUND: Growing evidence indicates that poor sleep harms health. Early to bed and early to rise is considered as a healthy lifestyle in Chinese population. The current study aimed to examine the effects of sleep habits on acute myocardial infarction (AMI) risk and severity of coronary artery disease (CAD) in Chinese population from two centers. METHODS: A total of 873 patients including 314 AMI cases and 559 controls were recruited from the inpatient cardiology department of the Affiliated Jiangning Hospital and the First Affiliated Hospital of Nanjing Medical University. 559 controls included 395 CAD cases and 164 non-CAD cases. We used a 17-item sleep factors questionnaire (SFQ) to evaluate sleep habits comprehensively by face-to-face interview. The severity of CAD was assessed by Gensini score in AMI and CAD groups. The effects of sleep factors on AMI risk and Gensini score were examined by unconditional logistic regression. RESULTS: After mutually adjustment for other sleep factors and demographic characteristics, the timing of sleep (24:00 and after) and morning waking (after 7:00) and sleep duration (< 6 h) were associated with increased risk of AMI (OR = 4.005, P < 0.001, OR = 2.544, P = 0.011 and OR = 2.968, P < 0.001, respectively). Lower level of light exposure at night was correlated with reduced risk of AMI (OR = 0.243, P = 0.009). In subgroup analysis by age, both late sleep timing and short sleep duration were associated with increased risk of AMI regardless of age. In subjects with age ≤ 65 years, daytime napping was related to reduced risk of AMI (OR = 0.645, P = 0.046). In subjects with age > 65 years, the frequency of night-time waking (3 times) was associated with increased risk of AMI (OR = 3.467, P = 0.035). Short sleep duration was correlated with increased risk of high Gensini score (OR = 2.374, P < 0.001). CONCLUSION: Sleep insufficiency is an important risk factor both for AMI risk and CAD severity. Late sleeping is also associated with increased risk of AMI. In young and middle-aged people, regular naps may have a protective effect.

Sleepy Surgeons: A Multi-Method Assessment of Sleep Deprivation and Performance in Surgery.

BACKGROUND: Minimum rest is mandated in high stake industries such as aviation. The current system of healthcare provision permits on-call surgeons to work in sleep deprived states when performing procedures. Fatigue has been demonstrated to negatively affect performance. This study aimed to explore measurements of sleep deprivation and their impact on simulated performance. METHODS: This was a single site study conducted between September 2019 and February 2020. Surgical trainee and consultants were conveniently sampled from a single site. All testing was done between 7 AM and 9 AM. Participants completed electroencephalogram testing using a modified Multiple Sleep Latency Test testing for objective sleep measurement, the Pittsburgh Sleep Quality Index, Chalder Fatigue Scale and Epworth Sleepiness Scale for subjective sleep measurement. The Psychomotor Vigilance Task and the SIMENDO simulated tasks were used for standardized performance assessment. RESULTS: Surgeons entered sleep in 6 min, on average pre-call. This significantly decreased to an average of 164 s post-call (P = 0.016). Pittsburgh Sleep Quality Index scoring was 5, indicating poor baseline sleep quality. There was higher self-reported fatigue and sleepiness in post-call states. Performance decrements were noted in cognitive performance reaction time and aspects of technical instrument proficiency. CONCLUSIONS: Surgeons are objectively sleep deprived pre-call according to internationally recognized guidelines. This sleep deprivation increases significantly in post-call states. Tasks with higher cognitive demands showed greater levels of diminished performance compared to those with lower cognitive demands. Current models of provision of surgical on-call are not conducive to optimizing sleep in surgeons. Prioritization of workload in post-call states, focusing on preserving individuals cognitive resources and utilizing lower cognitively demanding aspects of work is likely to have positive impacts on performance outcomes.

Abnormally abrupt transitions from sleep-to-wake in Huntington's disease sheep (Ovis aries) are revealed by automated analysis of sleep/wake transition dynamics.

Sleep disturbance is a common and disruptive symptom of neurodegenerative diseases such as Alzheimer's and Huntington's disease (HD). In HD patients, sleep fragmentation appears at an early stage of disease, although features of the earliest sleep abnormalities in presymptomatic HD are not fully established. Here we used novel automated analysis of quantitative electroencephalography to study transitions between wake and non-rapid eye movement sleep in a sheep model of presymptomatic HD. We found that while the number of transitions between sleep and wake were similar in normal and HD sheep, the dynamics of transitions from sleep-to-wake differed markedly between genotypes. Rather than the gradual changes in EEG power that occurs during transitioning from sleep-to-wake in normal sheep, transition into wake was abrupt in HD sheep. Furthermore, transitions to wake in normal sheep were preceded by a significant reduction in slow wave power, whereas in HD sheep this prior reduction in slow wave power was far less pronounced. This suggests an impaired ability to prepare for waking in HD sheep. The abruptness of awakenings may also have potential to disrupt sleep-dependent processes if they are interrupted in an untimely and disjointed manner. We propose that not only could these abnormal dynamics of sleep transitions be useful as an early biomarker of HD, but also that our novel methodology would be useful for studying transition dynamics in other sleep disorders.

Medication Errors in Surgery: A Classification Taxonomy and a Pilot Study in Postcall Residents.

INTRODUCTION: The post-call state in postgraduate medical trainees is associated with impaired decision-making and increased medical errors. An association between post-call state and medication prescription errors for surgery residents is yet to be established. Our objective was to determine whether post-call state is associated with increased proportion of medication prescription errors committed by surgery residents in an academic hospital without a computerized physician order entry (CPOE) system. METHODS: This prospective observational study was conducted at a tertiary academic hospital between June 28 and August 31, 2017. It compared the proportion of medication prescription errors committed by surgery residents in their post-call (PC) and no-call (NC) states. A novel taxonomy was developed to classify medication prescription errors. RESULTS: Sixteen of twenty-one eligible residents (76%) participated in this study. Self-reported hours of sleep per night was significantly higher in the NC group compared to the PC group (6(4-8) vs 2(0-4) hours, P < 0.01). PC residents committed a significantly higher proportion of medication prescription errors versus NC residents (9.2% vs 3.2%; p=0.04). Decision-making and prescription-writing errors comprised 33% and 67% of errors, respectively. CONCLUSIONS: The post-call state in surgery residents is associated with a significantly higher proportion of medication prescription errors in a hospital without a CPOE system. Decision-making and prescription-writing errors could potentially be addressed by additional educational interventions.

Injury crashes and the relationship with disease causing excessive daytime sleepiness.

OBJECTIVE: The objective of this study was to understand the relationship between some of the most common diseases that are known to contribute to excessive daytime sleepiness (EDS) and traffic injury crashes. Specific focus was on the relationship between disease and crash type (single-vehicle or multiple-vehicle crash) and between disease and injury severity. METHODS: This registry-based study considered all passenger car drivers involved in a crash in Sweden between 2011 and 2016 who were 40 years or older at the time of the crash (n = 54,090). For each crash-involved driver, selected medical diagnoses registered from 1997 until the day before the crash were extracted from the National Patient Register. The drivers were assigned to 1 of 4 groups, depending on prior diseases: sleep apnea (SA; group 1, n = 2,165), sleep disorders (group 2, n = 724), Parkinson's or epilepsy (group 3, n = 645) and a reference group (group 4, n = 50,556). Logistic regression analysis compared single-vehicle crashes with multiple-vehicle crashes and moderately/severely injured drivers with slightly/uninjured drivers. RESULTS: Drivers with EDS-related diseases (groups 1-3) had higher probability of a single-vehicle crash than a multiple-vehicle crash compared to the reference group. The most sizeable effect was found for Parkinson's/epilepsy with an odds ratio (OR) of 2.5 (confidence interval [CI], 2.1-3.0). For multiple-vehicle crashes, the probability of a moderate/severe injury was higher for drivers with other sleep disorders (OR = 1.5; CI, 1.0-2.2) and Parkinson's/epilepsy (OR = 1.6; CI, 1.1-2.3) compared to the reference group. CONCLUSIONS: This study has made first steps toward understanding the relationship between some of the most common diseases that are known to contribute to EDS and crashes. Having Parkinson's/epilepsy, in particular, elevated the probability of a single-vehicle crash compared to a multiple-vehicle crash. A single-vehicle crash was seen as indicative of causing a crash; thus, having Parkinson's/epilepsy could be interpreted as a risk factor for crash involvement. Having Parkinson's/epilepsy, as well as other sleep disorders, was also related to more severe outcomes in multiple-vehicle crashes, given that a crash occurred. This was not identified in single-vehicle crashes.

Regular aerobic exercise counteracts endothelial vasomotor dysfunction associated with insufficient sleep.

Insufficient sleep is associated with endothelial vasomotor dysfunction and increased cardiovascular risk. Regular aerobic exercise is an effective lifestyle strategy for improving endothelial function and, in turn, reducing cardiovascular risk. We tested the hypotheses that regular aerobic exercise would 1) improve endothelial vasodilation and 2) decrease endothelin (ET)-1-mediated vasoconstrictor tone in middle-aged adults who chronically sleep <7 h/night. Thirty-six healthy, middle-aged adults were studied: 16 with normal sleep duration (age: 57 ± 2 yr; sleep duration: 7.4 ± 0.1 h/night) and 20 with short sleep duration (age: 56 ± 1 yr; sleep duration: 6.2 ± 0.1 h/night). The 20 short sleepers completed a 3-mo aerobic exercise training intervention. Forearm blood flow was determined (via plethysmography) in response to intra-arterial acetylcholine (ACh), BQ-123 (ETA receptor antagonist), ACh + BQ-123, and sodium nitroprusside. Forearm blood flow responses to ACh were lower (∼20%; P < 0.05) in the short (from 4.2 ± 0.2 to 10.5 ± 0.6 mL/100 mL tissue/min) versus normal (4.2 ± 0.2 to 12.7 ± 0.6 mL/100 mL tissue/min) sleepers. In response to BQ-123, the short-sleep group had a significantly greater increase in resting forearm blood flow than the normal-sleep group (∼25% vs. ∼8%). ACh + BQ-123 resulted in a significant (∼25%) increase in the ACh-mediated vasodilation in the short-sleep group only. After exercise training, although nightly sleep duration was unchanged (6.4 ± 0.1 h/night), ACh-mediated vasodilation was significantly higher (∼20%), ET-1-mediated vasoconstriction was significantly lower (∼80%), and the vasodilator response to ACh was not increased with ETA receptor blockade. Regular aerobic exercise, independent of changes in nightly sleep duration, can counteract insufficient sleep-related endothelial vasomotor dysfunction.NEW & NOTEWORTHY Habitual insufficient nightly sleep (<7 h/night) is associated with increased risk of cardiovascular disease and events. Endothelial dysfunction, specifically reduced endothelium-dependent vasodilation and increased endothelin (ET)-1-mediated vasoconstriction, is considered to be a major contributing mechanism underlying increased vascular risk with insufficient sleep. In contrast to insufficient sleep, regular aerobic exercise enhances endothelial vasomotor function, reducing the risk of cardiovascular disease and associated events. In the present study, we determined the effects of aerobic exercise training on endothelium-dependent vasodilation and ET-1 vasoconstriction in adults who habitually sleep <7 h/night. After exercise training, although nightly sleep duration was unchanged, endothelium-dependent vasodilation was significantly enhanced and ET-1-mediated vasoconstrictor tone was significantly reduced in adults who sleep <7 h/night. Regular aerobic exercise training can mitigate insufficient sleep-related endothelial vasomotor dysfunction and, in turn, potentially reduce the cardiovascular risk associated with habitual insufficient nightly sleep.

Short duration of sleep and incidence of overweight or obesity in Chinese children and adolescents: A systematic review and meta-analysis of prospective studies.

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.

Sleep Fragmentation and Cognitive Trajectories After Critical Illness.

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.

Pilot study: can machine learning analyses of movement discriminate between leg movements in sleep (LMS) with vs. without cortical arousals?

PURPOSE: Clinical and animal studies indicate frequent small micro-arousals (McA) fragment sleep leading to health complications. McA in humans is defined by changes in EEG and EMG during sleep. Complex EEG recordings during the night are usually required to detect McA-limiting large-scale, prospective studies on McA and their impact on health. Even with the use of EEG, reliably measuring McA can be difficult because of low inter-scorer reliability. Surrogate measures in place of EEG could provide easier and possibly more reliable measures of McA. These have usually involved measuring heart rate and arm movements. They have not provided a reliable measurement of McA in part because they cannot adequately detect short wake periods and periods of wake after sleep onset. Leg movements in sleep (LMS) offer an attractive alternative. LMS and cortical arousal, including McA, commonly occur together. Not all McA occur with LMS, but the most clinically significant ones may be those with LMS [1]. Conversely, most LMS do not occur with McA, but LMS vary considerably in their characteristics. Evaluating LMS characteristics may serve to identify the LMS associated with McA. The use of standard machine learning approaches seems appropriate for this particular task. This proof-of-concept pilot project aims to determine the feasibility of detecting McA from machine learning methods analyzing movement characteristics of the LMS. METHODS: This study uses a small but diverse group of subjects to provide a large variety of LMS and McA adequate for supervised machine learning. LMS measurements were obtained from a new advanced technology in the RestEaZe™ leg band that integrates gyroscope, accelerometer, and capacitance measurements. Eleven RestEaZe™ LMS features were selected for logistic regression analyses. RESULTS: With the optimum logit probability threshold selected, the system accurately detected 76% of the McA matching the accuracy of trained visual inter-scorer reliability (71-76%). The classifier provided a sensitivity of 76% and a specificity of 86% for the identification of the LMS with McA. The classifier identified regions in sleep with high versus low rates of LMS with McA, indicating possible areas of fragmented versus undisturbed restful sleep. CONCLUSION: These pilot data are encouraging as a preliminary proof-of-concept for using advanced machine learning analyses of LMS to identify sleep fragmented by McA.

Longer duration electroencephalogram arousals have a better relationship with impaired vigilance and health status in obstructive sleep apnoea.

PURPOSE: Obstructive sleep apnoea (OSA) is a prevalent sleep disorder with significant health consequences. Sleep fragmentation is a feature of OSA and is often determined by the arousal index (ArI), a metric based on the electroencephalograph (EEG). The ArI has a weak correlation with neurocognitive outcomes in OSA patients. In this study, we examine whether changing from the current minimum EEG arousal duration of 3 s improves the association between sleep fragmentation and neurocognitive outcomes. METHODS: In a retrospective study, we selected OSA patients without any other comorbidities that are associated with neurocognitive impairment. The OSA patients were clustered into two groups based on their psychomotor vigilance task (PVT) performance to represent impaired and unimpaired neurocognition. RESULTS: While no differences were found in demographics or usual sleep study statistics, the impaired group had a greater number of EEG arousals greater than 5 s (P = 0.034), 7 s (P = 0.041), and 15 s (P = 0.036) in duration. There were no differences in the number of EEG arousals associated with sleep-disordered breathing events. These differences also corresponded with quality of life outcomes between the two groups. An ArI with a duration of 5 s or greater had the best combination of sensitivity (70.0%) and specificity (66.7%) compared with the usual 3 s duration (sensitivity and specificity of 70.0% and 53.3%, respectively). CONCLUSION: A re-examination of the EEG arousal scoring rules, and their duration, may help with allocation of health resources to OSA patients most in need.

Extending sleep to confirm insufficient sleep syndrome is challenging.

Insufficient sleep syndrome (ISS) is prevalent, but poorly studied. This descriptive study was performed to determine its diagnostic challenges and clinical characteristics in a large (n = 3,461) retrospective sample from a single sleep laboratory. Based on actigraphy, polysomnography and multiple sleep latency tests, we diagnosed "suspected insufficient sleep syndrome" in patients with chronic sleepiness, short time in bed, longer sleep duration during weekends or vacation, and without evidence of other causes of sleepiness. For the diagnosis of "definite insufficient sleep syndrome", we additionally required objectively confirmed resolution of sleepiness with actigraphy-documented extension of time in bed. We diagnosed "suspected insufficient sleep syndrome" in 300 subjects. In 94 subjects, extension of sleep time with consecutive relief of sleepiness was attempted, but only 37 subjects succeeded, often despite being offered several attempts. "Definite insufficient sleep syndrome" was confirmed in 36 patients. In these subjects, mean time in bed after sleep extension was above 8 hr per night and 84 min longer than at baseline. Narcolepsy-like findings were frequently observed before sleep extension, but no sleep onset rapid eye movement sleep on polysomnography. This study indicates that fulfilling the diagnostic criteria of ISS is challenging in clinical practice. It further corroborates the importance of actigraphy and polysomnography for correct diagnosis.

Evaluation of the postural balance and visual perception in young adults with acute sleep deprivation.

BACKGROUND/OBJECTIVE: Few studies have suggested a relationship between vestibular system and sleep deprivation. The aim of the present study is to investigate the effects of acute sleep deprivation lasting 24 hours or more on the postural balance and the visual abilities related to the vestibular system in healthy young adults. METHODS: Thirty-one healthy young adults (8 males, 23 female; ages 18- 36 years) who had experienced at least 24 hours of sleep deprivation were included in the study. Subjects made two visits to the test laboratory. One visit was scheduled during a sleep deprivation (SD) condition, and the other was scheduled during a daily life (DL) condition. Five tests- the Sensory Organization Test (SOT), Static Visual Acuity Test (SVA), Minimum Perception Time Test (mPT), Dynamic Visual Acuity Test (DVA), and Gaze Stabilization Test (GST)- were performed using a Computerized Dynamic Posturography System. RESULTS: A statistically significant difference was found between SD and DL measurements in somatosensorial (p = 0.003), visual (p = 0.037), vestibular (p = 0.008) ratios, and composite scores (p = 0.001) in SOT. The mPT results showed a statistically significant difference between SD and DL conditions (p = 0.001). No significant difference was found between SD and DL conditions in the comparison of the mean SVA (p = 0.466), DVA (p = 0.192), and GST head velocity values (p = 0.160). CONCLUSIONS: Sleep deprivation has a considerable impact on the vestibular system and visual perception time in young adults. Increased risk of accidents and performance loss after SD were thought to be due to the postural control and visual processing parameters rather than dynamic visual parameters of the vestibular system.

Home-EEG assessment of possible compensatory mechanisms for sleep disruption in highly irregular shift workers - The ANCHOR study.

STUDY OBJECTIVES: While poor sleep quality has been related to increased risk of Alzheimer's disease, long-time shift workers (maritime pilots) did not manifest evidence of early Alzheimer's disease in a recent study. We explored two hypotheses of possible compensatory mechanisms for sleep disruption: Increased efficiency in generating deep sleep during workweeks (model 1) and rebound sleep during rest weeks (model 2). METHODS: We used data from ten male maritime pilots (mean age: 51.6±2.4 years) with a history of approximately 18 years of irregular shift work. Subjective sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI). A single lead EEG-device was used to investigate sleep in the home/work environment, quantifying total sleep time (TST), deep sleep time (DST), and deep sleep time percentage (DST%). Using multilevel models, we studied the sleep architecture of maritime pilots over time, at the transition of a workweek to a rest week. RESULTS: Maritime pilots reported worse sleep quality in workweeks compared to rest weeks (PSQI = 8.2±2.2 vs. 3.9±2.0; p<0.001). Model 1 showed a trend towards an increase in DST% of 0.6% per day during the workweek (p = 0.08). Model 2 did not display an increase in DST% in the rest week (p = 0.87). CONCLUSIONS: Our findings indicated that increased efficiency in generating deep sleep during workweeks is a more likely compensatory mechanism for sleep disruption in the maritime pilot cohort than rebound sleep during rest weeks. Compensatory mechanisms for poor sleep quality might mitigate sleep disruption-related risk of developing Alzheimer's disease. These results should be used as a starting point for future studies including larger, more diverse populations of shift workers.

Is poor self-rated sleep quality associated with elevated systemic inflammation in healthy older adults?

OBJECTIVE: Examine subjective sleep quality and inflammation among healthy older adults participating in the Australian Research Council Longevity Intervention (ARCLI). METHODS: Data was taken from a sub-set of 232 participants aged between 60-70 years (M = 65.88 ± SD 4.08 years) who participated in the baseline assessment phase of the Australian Research Council Longevity Intervention (ARCLI) study. Subjective sleep was assessed via the Leeds Sleep Evaluation Questionnaire (LSEQ). Inflammatory markers (TNF-α, IL-1ß, IL-6, IL-10, IL-2, IFN-γ, IL-4, hs-CRP) were derived from whole blood. Correlation and multiple regression analyses were used to examine associations between each of the four sleep outcome variables and inflammatory outcomes, examined as a group and following gender stratification. RESULTS: Difficulties getting to sleep were independently associated with higher IL-2 [F(1,156) = 4.62, adjusted R2 = 0.02, p = 0.03] and IL-1ß [F(1,141) = 8.52, adjusted R2 = 0.05, p = 0.004] (whole group). Difficulties getting to sleep were associated with greater IL-1ß [males: F(1,58) = 7.36, adjusted R2 = 0.097 p = 0.009; females: F (1,81) = 4.25, R2 = 0.038, p = 0.04], and negatively associated with hs-CRP (women) [F (1,129) = 4.71, R2 = 0.028, p = 0.032]. DISCUSSION: Subjective sleep-onset difficulties are associated with systemic inflammation.