Psychoactive drug and medication use among patients referred to a tertiary sleep laboratory population.

Psychoactive drugs including alcohol, caffeine, and prescription medications are commonly consumed to alter sleep/wake states, however the prevalence and impact of these drugs among populations seeking assessment from sleep physicians are unknown. We investigated the prevalence of commonly used drugs (alcohol and caffeine), and medications in a population (N=120; 50 females and 70 males) attending a tertiary sleep clinic for diagnostic polysomnography (PSG) assessment. In addition to objective sleep assessment, participants completed questionnaires assessing sleep quality (Pittsburgh Sleep Quality Index, PSQI), daytime sleepiness (Epworth Sleepiness Scale, ESS), depression and anxiety (Hospital Anxiety and Depression Scale, HADS), alcohol use (Alcohol Use Disorders Identification Test, AUDIT), caffeine and medication use, as well as their experience of adverse events (motor vehicle accidents and near-miss crashes). Caffeine was consumed by 90% of the population and was associated with a reduction in excessive sleepiness symptomology; while high AUDIT scores were associated with increased near-miss crashes. Polypharmacy was common, with a greater number of medications associated with poorer sleep quality, and changes in sleep architecture. This study maps commonly used drugs in those attending a tertiary sleep clinic, and demonstrates associations between drug use and sleep outcomes assessed objectively and subjectively.

Association of Rapid Eye Movement Sleep With Mortality in Middle-aged and Older Adults.

Importance: Rapid eye movement (REM) sleep has been linked with health outcomes, but little is known about the relationship between REM sleep and mortality. Objective: To investigate whether REM sleep is associated with greater risk of mortality in 2 independent cohorts and to explore whether another sleep stage could be driving the findings. Design, Setting, and Participants: This multicenter population-based cross-sectional study used data from the Outcomes of Sleep Disorders in Older Men (MrOS) Sleep Study and Wisconsin Sleep Cohort (WSC). MrOS participants were recruited from December 2003 to March 2005, and WSC began in 1988. MrOS and WSC participants who had REM sleep and mortality data were included. Analysis began May 2018 and ended December 2019. Main Outcomes and Measures: All-cause and cause-specific mortality confirmed with death certificates. Results: The MrOS cohort included 2675 individuals (2675 men [100%]; mean [SD] age, 76.3 [5.5] years) and was followed up for a median (interquartile range) of 12.1 (7.8-13.2) years. The WSC cohort included 1386 individuals (753 men [54.3%]; mean [SD] age, 51.5 [8.5] years) and was followed up for a median (interquartile range) of 20.8 (17.9-22.4) years. MrOS participants had a 13% higher mortality rate for every 5% reduction in REM sleep (percentage REM sleep SD = 6.6%) after adjusting for multiple demographic, sleep, and health covariates (age-adjusted hazard ratio, 1.12; fully adjusted hazard ratio, 1.13; 95% CI, 1.08-1.19). Results were similar for cardiovascular and other causes of death. Possible threshold effects were seen on the Kaplan-Meier curves, particularly for cancer; individuals with less than 15% REM sleep had a higher mortality rate compared with individuals with 15% or more for each mortality outcome with odds ratios ranging from 1.20 to 1.35. Findings were replicated in the WSC cohort despite younger age, inclusion of women, and longer follow-up (hazard ratio, 1.17; 95% CI, 1.03-1.34). A random forest model identified REM sleep as the most important sleep stage associated with survival. Conclusions and Relevance: Decreased percentage REM sleep was associated with greater risk of all-cause, cardiovascular, and other noncancer-related mortality in 2 independent cohorts.

Association of Circadian Abnormalities in Older Adults With an Increased Risk of Developing Parkinson Disease.

Importance: Disruption in circadian activity rhythms is very common in older adults, particularly among those with neurodegenerative diseases, including Parkinson disease (PD). However, whether circadian disruption could be a prodrome for PD is unclear. Objective: To determine the association between rest-activity rhythm (RAR) and risk of incident PD and to explore whether this association is independent of nighttime sleep disturbances. Design, Setting, and Participants: The ancillary sleep study of the longitudinal cohort Osteoporotic Fractures in Men Study (MrOS) was conducted from December 1, 2003, to March 31, 2005. Of the 3135 community-dwelling men enrolled in the MrOS sleep study, 3049 had technically adequate RAR data; of these, 119 were excluded for having prevalent PD or missing incident data, leaving 2930 men without PD at baseline. Data were analyzed from February 1 through August 31, 2019. Exposures: Twenty four-hour RAR parameters (amplitude, mesor, robustness, and acrophase) generated by wrist actigraphy-extended cosinor analysis. Main Outcomes and Measures: Incident PD based on physician diagnosis. Multivariable logistic regression was used to determine the association between quartiles of RAR parameters and risk of incident PD. Results: Among the 2930 men included in the analysis (mean [SD] age, 76.3 [5.5] years), 78 (2.7%) developed PD during 11 years of follow-up. After accounting for all covariates, the risk of PD increased with decreasing circadian amplitude (strength of the rhythm) (odds ratio [OR] per 1-SD decrease, 1.77; 95% CI, 1.30-2.41), mesor (mean level of activity) (OR per 1-SD decrease, 1.64; 95% CI, 1.22-2.21), or robustness (how closely activity follows a cosine 24-hour pattern) (OR per 1-SD decrease, 1.54; 95% CI, 1.14-2.07) (P < .005 for trend). Those in the lowest quartile of amplitude, mesor, or robustness had approximately 3 times the risk of developing PD compared with those in the highest quartile of amplitude (OR, 3.11; 95% CI, 1.54-6.29), mesor (OR, 3.04; 95% CI, 1.54-6.01), and robustness (OR, 2.65; 95% CI, 1.24-5.66). The association remained after further adjustment for nighttime sleep disturbances and duration in the lowest compared with the highest quartile (OR for amplitude, 3.56 [95% CI, 1.68-7.56]; OR for mesor, 3.24 [95% CI, 1.52-6.92]; and OR for robustness, 3.34 [95% CI, 1.45-7.67]). These associations were somewhat attenuated, but the pattern remained similar after excluding PD cases developed within 2 years after baseline in the lowest compared with the highest quartile (OR for amplitude, 2.40 [95% CI, 1.15-5.00]; OR for mesor, 2.76 [95% CI, 1.35-5.67]; and OR for robustness, 2.33 [95% CI, 1.07-5.07]). Acrophase was not significantly associated with risk of PD. Conclusions and Relevance: In this cohort study, reduced circadian rhythmicity was associated with an increased risk of incident PD, suggesting it may represent an important prodromal feature for PD. Future studies are needed to determine whether circadian disruption could also be a risk factor for PD and whether strategies to improve circadian function affect the risk of PD.

Cardiometabolic comorbidities in obstructive sleep apnea patients are related to disease severity, nocturnal hypoxemia, and decreased sleep quality.

BACKGROUND: Obstructive sleep apnea syndrome (OSA) is currently recognized as an independent risk factor for hypertension, arrhythmia, coronary heart disease, stroke, and metabolic disorders (e.g. diabetes, dyslipidemia). In clinical practice, apnea-hypopnea index (AHI) is the marker used to classify disease severity and guide treatment. However, AHI alone does not sufficiently identify OSA patients at risk for cardiometabolic comorbidities. With this in mind, the aim of this retrospective study was to determine whether some polysomnographic parameters (e.g. apnea-hypopnea duration, sleep structure, nocturnal hypoxemia) are specifically associated with cardiometabolic comorbidities in OSA. METHODS: In this retrospective study, 1717 patients suffering from moderate/severe OSA were included between 2013 and 2017. Data on demographics, comorbidities, and polysomnographic characteristics were collected and analyzed to identify factors associated with cardiometabolic complications. RESULTS: The medical files of 1717 patients (68% male) were reviewed. The mean AHI was 43.1 +/- 27.7 with 57.3% of patients suffering from severe OSA, and 52% from at least one cardiovascular comorbidity (CVCo). Diabetes affected 22% of the patients and 27% exhibited dyslipidemia. Patients affected by CVCos were older, and more often women and non-smokers. These patients also had worse sleep quality, and a more marked intermittent/global nocturnal hypoxemia. With regard to diabetes, diabetics were older, more often non-smoker, non-drinker women, and were more obese. These patients also exhibited more severe OSA, especially in non-REM (NREM) sleep, worse sleep quality, and a more marked intermittent/global nocturnal hypoxemia. Dyslipidemia was more frequent in the absence of alcohol consumption, and was associated with OSA severity, decreased sleep quality, and longer AH in REM sleep. CONCLUSIONS: This study identifies demographic and polysomnographic factors associated with cardiometabolic comorbidities. Patients (especially women) suffering from more severe OSA, longer sleep apneas and hypopneas, worse sleep quality, and marked intermittent/global nocturnal hypoxemia are more likely to develop cardiometabolic comorbidities. This should stimulate clinicians to obtain adequate treatment in this population.

Point-of-Care Ultrasound for Obstructive Sleep Apnea Screening: Are We There Yet? A Systematic Review and Meta-analysis.

BACKGROUND: Perioperative diagnosis of obstructive sleep apnea (OSA) has important resource implications as screening questionnaires are overly sensitive, and sleep studies are expensive and time-consuming. Ultrasound (US) is a portable, noninvasive tool potentially useful for airway evaluation and OSA screening in the perioperative period. The objective of this systematic review was to evaluate the correlation of surface US with OSA diagnosis and to determine whether a point-of-care ultrasound (PoCUS) for OSA screening may help with improved screening in perioperative period. METHODS: A search of all electronic databases including Medline, Embase, and Cochrane Database of Systematic Reviews was conducted from database inception to September 2017. Inclusion criteria were observational cohort studies and randomized controlled trials of known or suspected OSA patients undergoing surface US assessment. Article screening, data extraction, and summarization were conducted by 2 independent reviewers with ability to resolve conflict with supervising authors. Diagnostic properties and association between US parameters (index test) and OSA diagnosis using sleep study (reference standard) were evaluated. The US parameters were divided into airway and nonairway parameters. A random-effects meta-analysis was planned, wherever applicable. RESULTS: Of the initial 3865 screened articles, 21 studies (7 airway and 14 nonairway) evaluating 3339 patients were included. Majority of studies were conducted in the general population (49%), respirology (23%), and sleep clinics (12%). No study evaluated the use of US for OSA in perioperative setting. Majority of included studies had low risk of bias for reference standard and flow and timing. Airway US parameters having moderate-good correlation with moderate-severe OSA were distance between lingual arteries (DLAs > 30 mm; sensitivity, 0.67; specificity, 0.59; 1 study/66 patients); mean resting tongue thickness (>60 mm; sensitivity, 0.85; specificity, 0.59; 1 study/66 patients); tongue base thickness during Muller maneuver (MM; sensitivity, 0.59; specificity, 0.78; 1 study/66 patients); and a combination of neck circumference and retropalatal (RP) diameter shortening during MM (sensitivity, 1.0; specificity, 0.65; 1 study/104 patients). Nonairway US parameters having a low-moderate correlation with moderate-severe OSA were carotid intimal thickness (pooled correlation coefficient, 0.444; 95% confidence interval [CI], 0.320-0.553; P value = .000, 8 studies/727 patients) and plaque presence (sensitivity, 0.24-0.75; specificity, 0.13-1.0; 4 studies/1183 patients). CONCLUSIONS: We found that a number of airway and nonairway parameters were identified with moderate to good correlation with OSA diagnosis in the general population. In future studies, it remains to be seen whether PoCUS screening for a combination of these parameters can address the pitfalls of OSA screening questionnaires.

Frequency and characteristic features of REM sleep without atonia.

OBJECTIVES: Isolated REM sleep without atonia (iRSWA) is regarded as prodromal phase of REM sleep behavior disorder (RBD) and synucleinopathies. Other factors, however, have also been described to cause RSWA, including sleep apnea, antidepressants use and narcolepsy. We investigated the frequency of RSWA and its different etiologies. METHODS: We investigated RSWA in patients that underwent a clinical video polysomnography. In iRSWA subjects, we examined polysomnography indication and two markers of prodromal Parkinson's disease: excessive daytime sleepiness and depressive symptoms, with a case-control design. RESULTS: Of the 864 included polysomnographies, 188 were positive for RSWA (21.8%), 17 for RBD (2.0%) and 48 for iRSWA (5.6%). Mean Epworth Sleepiness Scale scores were 9.8 ±â€¯4.8 (iRSWA subjects) and 7.5 ±â€¯4.9 (controls), p = 0.014. Mean Beck Depression Inventory-II scores were 11.3 ±â€¯7.9 (iRSWA subjects) and 9.5 ±â€¯8.4 (controls), p = 0.229. Excessive daytime sleepiness was more often the polysomnography indication in the iRSWA group (p = 0.006). CONCLUSIONS: RSWA is a frequent finding in the context of antidepressant use or synucleinopathies. iRSWA subjects reported increased excessive daytime sleepiness and more often had excessive daytime sleepiness as polysomnography indication. SIGNIFICANCE: Our study provides evidence for high frequency of RSWA, underscoring the need for longitudinal studies in iRSWA patients, with interest for conversion to synucleinopathies.

REM sleep muscle activity in idiopathic REM sleep behavior disorder predicts phenoconversion.

OBJECTIVE: To determine whether REM sleep without atonia (RSWA) during polysomnography (PSG) predicts phenoconversion in patients with idiopathic REM sleep behavior disorder (iRBD), a prodromal feature of a neurodegenerative disease. METHODS: We analyzed RSWA in 60 patients with iRBD, including manual phasic, tonic, and any muscle activity in the submentalis and anterior tibialis muscles and the automated REM atonia index in the submentals. We identified patients who developed parkinsonism or mild cognitive impairment (MCI) during at least 3 years of follow-up after PSG. Kaplan-Meier analysis was performed and receiver operator curves were calculated to determine RSWA cutoffs predicting faster phenoconversion. RESULTS: Twenty-six (43%) patients developed parkinsonism (n = 17) or MCI (n = 9). Phenoconverters were older at iRBD diagnosis (p = 0.02). Median time to phenoconversion was 3.9 ± 2.5 years. iRBD phenoconverters had significantly more RSWA at diagnosis. Phenoconversion risk from iRBD diagnosis was 20% and 35% at 3 and 5 years, respectively, with greater risk in patients with iRBD with >46.4% any combined RSWA, which increased further to 30% and 55% at 3 and 5 years for patients >65 years of age at diagnosis. CONCLUSIONS: Patients with iRBD with higher amounts of polysomnographic RSWA had a greater risk of developing Parkinson disease or MCI. Patients with older age and higher RSWA amounts had more rapid phenoconversion than younger patients with RBD. Our study suggests that RSWA is a potential biomarker for risk stratification of iRBD phenoconversion that could facilitate prognostication for patients with iRBD. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for patients with iRBD, increased RSWA correlates with increased risk for developing parkinsonism or MCI.

Practical aspects of actigraphy and approaches in clinical and research domains.

Actigraphy involves acquisition of data using a movement sensor worn continuously on the nondominant wrist, typically for a week or more. Computer-based algorithms estimate sleep episodes by analysis of continuous minutes of no to low movement, or spans of time when movement is relatively low compared with movements during presumed ambulatory wakefulness. Inherent advantages of actigraphy over polysomnography include its noninvasive nature, cost-effectiveness, lesser burden on patients/research participants, and ability to collect data over multiple days/nights, thereby allowing examination of sleep-wake patterning. Therefore, actigraphy is emerging as a common method to objectively assess sleep parameters providing estimates of sleep duration and continuity. Modes of actigraphy data collection, scoring algorithms, sleep quality/disturbance measures, validation studies, and clinical and research applications are discussed.

Update on the assessment and investigation of adult obstructive sleep apnoea.

BACKGROUND: Obstructive sleep apnoea (OSA) is common. Medicare Benefits Schedule rules regarding which patients are eligible for a sleep study without first needing to see a sleep or respiratory specialist have recently changed and incorporate validated questionnaires of OSA risk and subjective sleepiness. OBJECTIVE: The aim of this article is to bring general practitioners (GPs) up to date with the key factors that should be assessed when considering whether a patient has OSA. It also highlights the strengths and weaknesses of the screening questionnaires, and the pros and cons of different types of sleep studies. DISCUSSION: OSA may significantly affect quality of life, mood, safety and cardiovascular risk. Assessment should focus on symptoms. Screening questionnaires have high sensitivity but, when used alone, poor specificity for moderate-to-severe OSA. The Epworth Sleepiness Scale (ESS) is a poor marker of OSA but does predict response to treatment when elevated. GPs can directly order sleep studies when OSA questionnaires are positive and the ESS is elevated; however, negative questionnaires do not exclude OSA or another sleep disorder.

An update on the current management of adult obstructive sleep apnoea.

BACKGROUND: Obstructive sleep apnoea (OSA) is common in adults. Various contributing factors to this condition have resulted in the development of a number of potential treatment modalities, some of which are in evolution. A multidisciplinary team involving the general practitioner is an important aspect in providing personalised care. OBJECTIVE: The aim of this review is to provide a clinical update on the recent developments and future directions in adult OSA management. DISCUSSION: In-lab polysomnography remains important in the diagnosis of OSA, although home sleep studies have good specificity and sensitivity in particular subgroups of patients. First-line therapy in adult OSA is continuous positive airway pressure, with mandibular advancement splints and surgical intervention considered second-line. Adjunctive therapies include weight loss, avoidance of supine sleep, management of nasal obstruction, alcohol intake limitation and exercise. Advancements in medications targeting multiple neurophysiological pathways, and surgical insertion of hypoglossal nerve stimulator devices represent possible future treatment pathways in Australia.

Short Average Duration of NREM/REM Cycle Is Related to Cognitive Decline in an Elderly Cohort: An Exploratory Investigation.

Prospective studies concerning sleep architecture and cognitive function have focused on individual sleep measures per se, without considering the complementary role of non-REM (NREM) and REM sleep. We explored the association between NREM/REM cycle-related sleep architecture and cognitive decline. Community-dwelling elderly people in Korea from the Korean Longitudinal Study on Cognitive Aging and Dementia were enrolled. They were cognitively normal and underwent overnight polysomnography at baseline. A NREM/REM cycle is a sequence of NREM and REM sleep, uninterrupted by a waking period of >2 min. After 4 years, the development of mild cognitive impairment (MCI) or dementia was related to the measures of sleep architecture, including NREM/REM cycle parameters by logistic regression analyses. Of 235 participants (mean [SD] age 68 [5] years; 60% female) at baseline, 14 (5.9%) developed MCI/dementia at follow-up. A short average cycle length (OR, 0.97 [95% CI, 0.94-0.99]; p = 0.02) was significantly associated with cognitive decline. When its substructure and NREM and REM sleep outside of cycles were considered simultaneously, the average REM sleep duration per cycle (OR, 0.87 [95% CI, 0.76-0.98]; p = 0.03) was significantly related to the outcome. In conclusion, short average duration of NREM/REM cycles, especially average REM sleep duration in each cycle, in cognitively normal elderly might be used as an early marker of cognitive decline.

Impact of autoimmune comorbidity on fatigue, sleepiness and mood in myasthenia gravis.

BACKGROUND: Disease burden in myasthenia gravis (MG) and in other autoimmune disorders is often determined by common accompanying symptoms such as fatigue, sleepiness and mood disturbances. Many MG patients have a second autoimmune disease, but it is unclear whether autoimmune comorbidities add to the severity of fatigue, sleepiness and mood disturbances. METHODS: We ascertained the presence of autoimmune comorbidities in 69 well-characterized MG patients. To assess fatigue, sleepiness and mood disturbances, we applied the Fatigue Severity Scale (FSS), the Fatigue Impact Scale (FIS), the Epworth Sleepiness Scale (ESS), as well as the Beck Depression Inventory (BDI) and State-Trait Anxiety Inventory (STAI) to all patients. RESULTS: Thirteen MG patients had concomitant autoimmune thyroid disease (AITD), including 1 patient with rheumatoid arthritis as third autoimmune disease. Fatigue (68.1%), excessive daytime sleepiness (14.5%), moderate-severe depression (20.3%) and anxiety (26.1%) were common, but MG patients with and without autoimmune comorbidities had similar FSS, FIS, ESS, BDI and STAI scores. The presence of autoimmune comorbidities was not associated with altered clinical and immunological MG characteristics, but MG patients with autoimmune comorbidities have more often been treated with corticosteroids than patients without autoimmune comorbidities (92.3% vs. 60.7%; p = 0.03). CONCLUSIONS: While many MG patients were affected by fatigue, sleepiness, depression and anxiety, the present study does not suggest that coexisting autoimmune diseases substantially contribute to the magnitude of these cumbersome comorbid symptoms. However, the higher frequency of steroid treatment may have counterbalanced the effects of the autoimmune comorbidity.

Dynamic changes in electroencephalogram spectral power with varying apnea duration in older adults.

Sleep apnea elicits brain and physiological changes and its duration varies across the night. This study investigates the changes in the relative powers in electroencephalogram (EEG) frequency bands before and at apnea termination and as a function of apnea duration. The analysis was performed on 30 sleep records (375 apnea events) of older adults diagnosed with sleep apnea. Power spectral analysis centered on two 10-s EEG epochs, before apnea termination (BAT) and after apnea termination (AAT), for each apnea event. The relative power changes in EEG frequency bands were compared with changes in apnea duration, defined as Short (between 10 and 20 s), Moderate (between 20 and 30 s) and Long (between 30 and 40 s). A significant reduction in EEG relative powers for lower frequency bands of alpha and sigma were observed for the Long compared to the Moderate and Short apnea duration groups at BAT, and reduction in relative theta, alpha and sigma powers for the Long compared to the Moderate and Short groups at AAT. The proportion of apnea events showed a significantly decreased trend with increased apnea duration for non-rapid eye movement sleep but not rapid eye movement sleep. The proportion of central apnea events decreased with increased apnea duration, but not obstructive episodes. The findings suggest EEG arousal occurred both before and at apnea termination and these transient arousals were associated with a reduction in relative EEG powers of the low-frequency bands: theta, alpha and sigma. The clinical implication is that these transient EEG arousals, without awakenings, are protective of sleep. Further studies with large datasets and different age groups are recommended.

Sleep alterations in pediatric bipolar disorder versus attention deficit disorder.

Bipolar disorder (BD) and attention deficit/hyperactivity disorder (ADHD) share numerous clinical features, which can make the differential diagnosis challenging. Studies conducted in adults suggest that patients with BD and ADHD have different sleep patterns. However, in pediatric populations, data on these potential differences are scant. The present preliminary study was conducted to identify potential differences in sleep alterations among youths diagnosed with BD or ADHD compared to healthy controls (HC). A total of 26 patients diagnosed with BD (n = 13) or ADHD (n = 13) were compared to 26 sex- and age-matched HC ([HCBD], n = 13, and [HCADHD], n = 13). All participants underwent polysomnography. The mean duration of stage N2 sleep was shorter in the BD group than in controls (HCBD). The BD group also had higher (non-significant) REM density (REMd) scores than controls while mean REMd scores were lower in the ADHD group versus controls. Compared to the ADHD group, the BD group presented a shorter N2 stage, a longer first REM sleep duration (R1), and greater REMd. According to our findings, these three variables-N2 stage, REMd, and R1-appear to differentiate patients with BD from those with ADHD and from HC.

Slow-wave sleep and motor progression in Parkinson disease.

Growing evidence from Alzheimer disease supports a potentially beneficial role of slow-wave sleep in neurodegeneration. However, the importance of slow-wave sleep in Parkinson disease is unknown. In 129 patients with Parkinson disease, we retrospectively tested whether sleep slow waves, objectively quantified with polysomnography, relate to longitudinal changes in Unified Parkinson's Disease Rating Scale motor scores. We found that higher accumulated power of sleep slow waves was associated with slower motor progression, particularly of axial motor symptoms, over a mean time of 4.6 ± 2.3 years. This preliminary finding suggests that deeper sleep relates to slower motor progression in Parkinson disease. Ann Neurol 2019;85:765-770.

Chronic sleep restriction greatly magnifies performance decrements immediately after awakening.

STUDY OBJECTIVES: Sleep inertia, subjectively experienced as grogginess felt upon awakening, causes cognitive performance impairments that can require up to 1.5 hr to dissipate. It is unknown, however, how chronic sleep restriction (CSR) influences the magnitude and duration of sleep inertia-related performance deficits. METHODS: Twenty-six healthy participants were enrolled in one of two in-laboratory sleep restriction protocols (one 32 day randomized control and one 38 day protocol) that separated the influence of sleep and circadian effects on performance using different "day"-lengths (20 and 42.85 hr day-lengths, respectively). The sleep opportunity per 24 hr day was the equivalent of 5.6 hr for each CSR condition and 8 hr for the Control condition. Participant's performance and subjective sleepiness were assessed within ~2 min after electroencephalogram-verified awakening and every 10 min thereafter for 70 min to evaluate performance and subjective sleepiness during sleep inertia. RESULTS: Performance within 2 min of awakening was ~10% worse in CSR conditions compared with Control and remained impaired across the dissipation of sleep inertia in the CSR conditions when compared with Control. These impairments in performance during sleep inertia occurred after only chronic exposure to sleep restriction and were even worse after awakenings during the biological nighttime. Interestingly, despite differences in objective performance, there were no significant differences between groups in subjective levels of sleepiness during sleep inertia. CONCLUSIONS: CSR worsens sleep inertia, especially for awakenings during the biological night. These findings are important for individuals needing to perform tasks quickly upon awakening, particularly those who obtain less than 6 hr of sleep on a nightly basis. CLINICAL TRIAL: The study "Sleep Duration Required to Restore Performance During Chronic Sleep Restriction" was registered as a clinical trial (#NCT01581125) at clinicaltrials.gov (https://clinicaltrials.gov/ct2/show/NCT01581125?term=NCT01581125.&rank=1).

Racial/ethnic disparities in women's sleep duration, continuity, and quality, and their statistical mediators: Study of Women's Health Across the Nation.

STUDY OBJECTIVES: To describe racial/ethnic differences in sleep duration, continuity, and perceived sleep quality in postmenopausal women and to identify statistical mediators of differences in sleep characteristics. METHODS: Recruited from the observational Study of Women's Health Across the Nation (SWAN), 1,203 (548 white, 303 black, 147 Chinese, 132 Japanese, and 73 Hispanic; mean age 65 years, 97% postmenopausal) women participated in a week-long actigraphy and daily diary study in 2013-2015. Actigraphic measures of sleep duration and wake after sleep onset (WASO), and diary-rated sleep quality were averaged across the week. Candidate mediators included health-related variables; stress; and emotional well-being assessed up to 13 times across 18 years from baseline to sleep study. RESULTS: Whites slept longer than other groups; the significant mediators were concurrent financial hardship and increasing number of stressors for Hispanics or Japanese versus whites. Whites had less WASO than blacks and Hispanics; significant mediators were concurrent number of health problems, physical inactivity, waist circumference, vasomotor symptoms, number of life stressors, and financial hardship, and increasing number of health problems from baseline to sleep study. Whites reported better sleep quality than blacks, Chinese, and Japanese; significant mediators were concurrent physical inactivity, vasomotor symptoms, positive affect, and depressive symptoms. CONCLUSIONS: Sleep differences between blacks or Hispanics versus whites were mediated by health problems, number of stressors, and financial hardship, whereas sleep differences between Chinese or Japanese versus whites were mediated by emotional well-being. This is the first study using formal mediational approaches.

Polysomnographic data in Dementia with Lewy Bodies: correlation with clinical symptoms and comparison with other α-synucleinopathies.

INTRODUCTION: Sleep dysfunction is frequent in Dementia with Lewy Bodies (DLB), but polysomnographic (PSG) data is scarce. Our objectives were to: (1) compare PSG data between DLB patients and age normative values (NV), Parkinson's Disease (PD) and idiopathic REM sleep behavior disorder (iRBD) patients; (2) evaluate the relation between of OSA, Fluctuations and Hypersomnolence and PSG data. METHODS: We selected all consecutive patients with DLB, PD and iRBD that underwent video-PSG during a two year period. Clinical data was collected by file review. Video-PSG data included sleep structure, Apnea-Hypopnea Index (AHI), REM sleep atonia indexes and video file inspection of motor events (ME) during REM sleep. RESULTS: Subjects: In this study, 19 DLB, 51 PD and 20 iRBD patients participated. Of those, nine DLB (DLB-RBD) and 23 PD (PD-RBD) patients had RBD. Compared to NV, DLB patients had significantly lower sleep efficiency, total sleep time, and REM sleep duration and higher sleep latency, wake after sleep onset and N2 duration. There were no significant relations between PSG data and OSA, hypersomnolence or fluctuations. Sleep latency and AHI were significantly higher and lower, respectively, in DLB compared to PD patients. ME frequency was higher in iRBD. CONCLUSION: DLB patients present significant sleep fragmentation and shortened total and REM sleep time. These changes were not related with OSA, fluctuations or hypersomnolence, suggesting a different pathophysiology. PSG data was similar in the three RBD groups, in accordance with a common neuropathological origin, except for an increase in RBD severity in patients with iRBD.

The first night effect during polysomnography, and patients' estimates of sleep quality.

We surveyed patients the next morning after in-laboratory polysomnography (PSG) to compare the first night effect (FNE) and reverse first night effect (RFNE) in different sleep disorders. A questionnaire was given to 852 patients with insomnia (n = 171), restless legs syndrome (n = 186), obstructive sleep apnea (n = 369), simple snoring (n = 54), REM sleep behavior disorder (n = 39), and hypersomnia (n = 33). FNE was seen in 48.9%, 30.5% slept as usual, and 20.6% had RFNE. The highest incidences of FNE were seen in OSA, simple snoring, hypersomnia, and in men. We propose to use these findings as a reference when interpreting nocturnal in-laboratory PSG results.

Differential effects of split and continuous sleep on neurobehavioral function and glucose tolerance in sleep-restricted adolescents.

STUDY OBJECTIVES: Many adolescents are exposed to sleep restriction on school nights. We assessed how different apportionment of restricted sleep (continuous vs. split sleep) influences neurobehavioral function and glucose levels. METHODS: Adolescents, aged 15-19 years, were evaluated in a dormitory setting using a parallel-group design. Following two baseline nights of 9-hour time-in-bed (TIB), participants underwent either 5 nights of continuous 6.5-h TIB (n = 29) or 5-hour nocturnal TIB with a 1.5-hour afternoon nap (n = 29). After two recovery nights of 9-hour TIB, participants were sleep restricted for another three nights. Sleep was assessed using polysomnography (PSG). Cognitive performance and mood were evaluated three times per day. Oral glucose tolerance tests (OGTT) were conducted on mornings after baseline sleep, recovery sleep, and the third day of each sleep restriction cycle. RESULTS: The split sleep group had fewer vigilance lapses, better working memory and executive function, faster processing speed, lower level of subjective sleepiness, and more positive mood, even though PSG-verified total sleep time was less than the continuous sleep group. However, vigilance in both sleep-restricted groups was inferior to adolescents in a prior sample given 9-hour nocturnal TIB. During both cycles of sleep restriction, blood glucose during the OGTT increased by a greater amount in the split sleep schedule compared with persons receiving 6.5-hour continuous sleep. CONCLUSIONS: In adolescents, modest multinight sleep restriction had divergent negative effects on cognitive performance and glucose levels depending on how the restricted sleep was apportioned. They are best advised to obtain the recommended amount of nocturnal sleep. TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT03333512.