Revisiting the maintenance of wakefulness test: from intra-/inter-scorer agreement to normative values in patients treated for obstructive sleep apnea.

The Maintenance of Wakefulness Test is widely used to objectively assess sleepiness and make safety-related decisions, but its interpretation is subjective and normative values remain debated. Our work aimed to determine normative thresholds in non-subjectively sleepy patients with well-treated obstructive sleep apnea, and to assess intra- and inter-scorer variability. We included maintenance of wakefulness tests of 141 consecutive patients with treated obstructive sleep apnea (90% men, mean (SD) age 47.5 (9.2) years, mean (SD) pre-treatment apnea-hypopnea index of 43.8 (20.3) events/h). Sleep onset latencies were independently scored by two experts. Discordant scorings were reviewed to reach a consensus and half of the cohort was double-scored by each scorer. Intra- and inter-scorer variability was assessed using Cohen's kappa for 40, 33, and 19 min mean sleep latency thresholds. Consensual mean sleep latencies were compared between four groups according to subjective sleepiness (Epworth Sleepiness Scale score < versus ≥11) and residual apnea-hypopnea index (< versus ≥15 events/h). In well-treated non-sleepy patients (n = 76), the consensual mean (SD) sleep latency was 38.4 (4.2) min (lower normal limit [mean - 2SD] = 30 min), and 80% of them did not fall asleep. Intra-scorer agreement on mean sleep latency was high but inter-scorer was only fair (Cohen's kappa 0.54 for 33-min threshold, 0.27 for 19-min threshold), resulting in changes in latency category in 4%-12% of patients. A higher sleepiness score but not the residual apnea-hypopnea index was significantly associated with a lower mean sleep latency. Our findings suggest a higher than usually accepted normative threshold (30 min) in this context and emphasise the need for more reproducible scoring approaches.

Smartphone-based virtual agents and insomnia management: A proof-of-concept study for new methods of autonomous screening and management of insomnia symptoms in the general population.

Insomnia is the most frequent sleep disorder, and the COVID-19 crisis has massively increased its prevalence in the population, due to psychosocial stress or direct viral contamination. KANOPEE_2 is a smartphone-based application that provides interactions with a virtual agent to autonomously screen and alleviate insomnia symptoms through an intervention programme giving personalized advices regarding sleep hygiene, relaxation techniques and stimulus-control. In this proof-of-concept study, we tested the effects of KANOPEE_2 among users from all over the country (France) who downloaded the app between 1 June and 26 October 2020 (to focus on effects after the end of COVID-19 confinement). Outcome measures include insomnia severity (Insomnia Severity Index) and sleep/wake schedules measured by a sleep diary. One-thousand and thirty-four users answered the screening interview (Mage  = 43.76 years; SD = 13.14), and 108 completed the two-step programme (Mage  = 46.64 years; SD = 13.63). Of those who answered the screening, 42.8% did not report sleep complaints, while 57.2% presented mild-to-severe insomnia symptoms. At the end of the intervention, users reported significantly fewer sleep complaints compared with the beginning of the intervention (Insomnia Severity Indexbeginning  = 13.58; Insomnia Severity Indexend  = 11.30; p < 0.001), and significantly increased their sleep efficiency (sleep efficiencybeginning  = 76.46%; sleep efficiencyend  = 80.17%; p = 0.013). KANOPEE_2 is a promising solution both to provide autonomous evaluation of individuals' sleep hygiene and reduce insomnia symptoms over a brief and simple intervention. These results are very encouraging for addressing the issue of insomnia management in people exposed to major psychosocial stress and the consequences of COVID-19 infection.

Insomnia does not affect heart rate changes when young adults watch humorous films: An exploratory study.

Emotional reactivity in insomnia is affected both subjectively and on a physiological level for negative emotional material, but little is known about reactions to positive stimuli. We here investigated whether in younger adult insomnia patients, presentation of short humorous films would lead to heart rate decreases during and after film viewing, as compared to heart rate changes when falling asleep. Investigating 20 participants with DSM-5-diagnosed insomnia and 18 participants without insomnia, we found that heart rate decreased when falling asleep, increased when watching humorous films and returned to normal values afterwards for all participants. Film-related heart rate increases were strongly related to humour ratings of the films. No differences were found between those with and without insomnia on subjective ratings of the films, film-related heart rate changes or when falling asleep. We conclude that the experience of positive daily life stimuli in younger adults is not affected by insomnia in our study, despite insomnia having a known more profound effect on negative stimuli. Future studies exploring insomnia-related autonomous nervous system responses combining different neurophysiological modalities should confirm our findings.

Altered sleep quality is associated with Crohn's disease activity: an actimetry study.

BACKGROUND: Sleep is involved in the regulation of inflammation, healing, and digestion. The pathophysiology of Crohn's disease (CD) is unclear, and the role of sleep disturbances has recently been suggested. OBJECTIVE: The present study investigated a putative association between sleep disturbances and CD activity. METHODS: We conducted a prospective observational monocenter translational study, recruiting major CD patients from 2013 to 2015. Disease activity was assessed by the Harvey-Bradshaw index and the CD activity index. Objective sleep quantity and quality were measured by wrist actigraphy over a period of 7 days. The primary objective was to look for an association between wrist actigraphy parameters and CD activity. RESULTS: Thirty-four CD patients, including 14 with active disease and 20 in remission, were included. Sleep efficiency measured by wrist actigraphy was lower in patients with active CD compared to patients in remission. Wake after sleep onset time best predicted CD activity with an AUROC of 0.83. Patients with active CD were more frequently characterized as "poor sleepers" and frequently suffered from excessive daytime sleepiness. CONCLUSION: Sleep efficiency is lower in patients with active CD than in those in remission. Further studies aimed at better characterizing CD patients' sleep are warranted.

Smartphone-Based Virtual Agents to Help Individuals With Sleep Concerns During COVID-19 Confinement: Feasibility Study.

BACKGROUND: The COVID-19 crisis and consequent confinement restrictions have caused significant psychosocial stress and reports of sleep complaints, which require early management, have increased during recent months. To help individuals concerned about their sleep, we developed a smartphone-based app called KANOPEE that allows users to interact with a virtual agent dedicated to autonomous screening and delivering digital behavioral interventions. OBJECTIVE: Our objective was to assess the feasibility of this app, in terms of inclusion rate, follow-up rate, perceived trust and acceptance of the virtual agent, and effects of the intervention program, in the context of COVID-19 confinement in France. METHODS: The virtual agent is an artificial intelligence program using decision tree architecture and interacting through natural body motion and natural voice. A total of 2069 users aged 18 years and above downloaded the free app during the study period (April 22 to May 5, 2020). These users first completed a screening interview based on the Insomnia Severity Index (ISI) conducted by the virtual agent. If the users were positive for insomnia complaints (ISI score >14), they were eligible to join the 2-stage intervention program: (1) complete an electronic sleep diary for 1 week and (2) follow personalized sleep recommendations for 10 days. We collected and analyzed the following measures: sociodemographic information, ISI scores and sleep/wake schedules, and acceptance and trust of the agent. RESULTS: Approximately 76% (1574/2069) of the app users completed the screening interview with the virtual agent. The virtual agent was well accepted by 27.4% (431/1574) of the users who answered the acceptance and trust questionnaires on its usability, satisfaction, benevolence, and credibility. Of the 773 screened users who reported sleep complaints (ISI score >14), 166 (21.5%) followed Step 1 of the intervention, and only 47 of those (28.3%) followed Step 2. Users who completed Step 1 found that their insomnia complaints (baseline mean ISI score 18.56, mean ISI score after Step 1 15.99; P<.001) and nocturnal sleep quality improved significantly after 1 week. Users who completed Step 2 also showed an improvement compared to the initial measures (baseline mean ISI score 18.87, mean ISI score after Step 2 14.68; P<.001). Users that were most severely affected (ISI score >21) did not respond to either intervention. CONCLUSIONS: These preliminary results suggest that the KANOPEE app is a promising solution to screen populations for sleep complaints and that it provides acceptable and practical behavioral advice for individuals reporting moderately severe insomnia.

Sleepiness and the transition from wakefulness to sleep.

The transition from wakefulness to sleep is a progressive process that is reflected in the gradual loss of responsiveness, an alteration of cognitive functions, and a drastic shift in brain dynamics. These changes do not occur all at once. The sleep onset period (SOP) refers here to this period of transition between wakefulness and sleep. For example, although transitions of brain activity at sleep onset can occur within seconds in a given brain region, these changes occur at different time points across the brain, resulting in a SOP that can last several minutes. Likewise, the transition to sleep impacts cognitive and behavioral levels in a graded and staged fashion. It is often accompanied and preceded by a sensation of drowsiness and the subjective feeling of a need for sleep, also associated with specific physiological and behavioral signatures. To better characterize fluctuations in vigilance and the SOP, a multidimensional approach is thus warranted. Such a multidimensional approach could mitigate important limitations in the current classification of sleep, leading ultimately to better diagnoses and treatments of individuals with sleep and/or vigilance disorders. These insights could also be translated in real-life settings to either facilitate sleep onset in individuals with sleep difficulties or, on the contrary, prevent or control inappropriate sleep onsets.

Why circadian rhythmicity matters: Associations between sleep irregularity and mental health conditions during the Covid-19 health crisis.

OBJECTIVE: To assess the association between sleep irregularity, anxiety, and depression while controlling for other sleep dimensions and using a longitudinal design. METHODS: Longitudinal cohort study which started in April 2020 during the first French lockdown in the general population. Follow-up questionnaires were completed in June 2020, a period without lockdown measures. Participants were asked about their sleep (regularity, duration, timing, complaints) and their anxiety (General Anxiety Disorder-7) and depressive (Patient Health Questionnaire-9) symptoms. RESULTS: A total of 3745 participants were included (mean age: 28.9 years) with 2945 women (78.6%). At baseline, 38.1% (1428) of participants reported irregular sleep timing, 23.8% (891) anxiety and 28.9% (1081) depressive symptoms. In cross-sectional analyses, irregular sleep timing was associated with a 2.5-fold higher likelihood of anxiety and a 4-fold higher likelihood of depressive symptoms compared to regular sleepers. Associations were not explained by the other sleep dimensions and persisted in a longitudinal analysis, with irregular sleep timing at baseline being associated with anxiety (OR = 3.27[1.58-6.76]) and depressive symptoms (OR = 3.45[1.66-7.19]) during follow-up. CONCLUSION: The results show a strong association between sleep irregularity and mental health. Furthers studies are needed to explore how sleep regularity could promote good mental health in non-clinical populations.

Sleepiness should be reinvestigated through the lens of clinical neurophysiology: A mixed expertal and big-data Natural Language Processing approach.

Historically, the field of sleep medicine has revolved around electrophysiological tools. However, the use of these tools as a neurophysiological method of investigation seems to be underrepresented today, from both international recommendations and sleep centers, in contrast to behavioral and psychometric tools. The aim of this article is to combine a data-driven approach and neurophysiological and sleep medicine expertise to confirm or refute the hypothesis that neurophysiology has declined in favor of behavioral or self-reported dimensions in sleep medicine for the investigation of sleepiness, despite the use of electrophysiological tools. Using Natural Language Processing methods, we analyzed the abstracts of the 18,370 articles indexed by PubMed containing the terms 'sleepiness' or 'sleepy' in the title, abstract, or keywords. For this purpose, we examined these abstracts using two methods: a lexical network, enabling the identification of concepts (neurophysiological or clinical) related to sleepiness in these articles and their interconnections; furthermore, we analyzed the temporal evolution of these concepts to extract historical trends. These results confirm the hypothesis that neurophysiology has declined in favor of behavioral or self-reported dimensions in sleep medicine for the investigation of sleepiness. In order to bring sleepiness measurements closer to brain functioning and to reintroduce neurophysiology into sleep medicine, we discuss two strategies: the first is reanalyzing electrophysiological signals collected during the standard sleep electrophysiological test; the second takes advantage of the current trend towards dimensional models of sleepiness to situate clinical neurophysiology at the heart of the redefinition of sleepiness.

Objective evaluation of excessive daytime sleepiness.

Excessive daytime sleepiness (EDS) is multifactorial. It combines, among other things, an excessive propensity to fall asleep ("physiological sleepiness") and a continuous non-imperative sleepiness (or drowsiness/hypo-arousal) leading to difficulties remaining awake and maintaining sustained attention and vigilance over the long term ("manifest sleepiness"). There is no stand-alone biological measure of EDS. EDS measures can either capture the severity of physiological sleepiness, which corresponds to the propensity to fall asleep, or the severity of manifest sleepiness, which corresponds to behavioral consequences of sleepiness and reduced vigilance. Neuropsychological tests (The psychomotor vigilance task (PVT), Oxford Sleep Resistance Test (OSLeR), Sustained Attention to Response Task (SART)) explore manifest sleepiness through several sustained attention tests but the lack of normative values and standardized protocols make the results difficult to interpret and use in clinical practice. Neurophysiological tests explore the two main aspects of EDS, i.e. the propensity to fall asleep (Multiple sleep latency test, MSLT) and the capacity to remain awake (Maintenance of wakefulness test, MWT). The MSLT and the MWT are widely used in clinical practice. The MSLT is recognized as the "gold standard" test for measuring the severity of the propensity to fall asleep and it is a diagnostic criterion for narcolepsy. The MWT measures the ability to stay awake. The MWT is not a diagnostic test as it is recommended only to evaluate the evolution of EDS and efficacy of EDS treatment. Even if some efforts to standardize the protocols for administration of these tests have been ongoing, MSLT and MWT have numerous limitations: age effect, floor or ceiling effects, binding protocol, no normal or cutoff value (or determined in small samples), and no or low test-retest values in some pathologies. Moreover, the recommended electrophysiological set-up and the determination of sleep onset using the 30­sec epochs scoring rule show some limitations. New, more precise neurophysiological techniques should aim to detect very brief periods of physiological sleepiness and, in the future, the brain local phenomenon of sleepiness likely to underpin drowsiness, which could be called "physiological drowsiness".

Validation of the French version of the Munich ChronoType questionnaire and associations between chronotype and physiological parameters.

Assessing chronotype is essential in clinical and research environments, but the Munich ChronoType Questionnaire (MCTQ), a widely utilised tool, is not available in French. Therefore, we carried out an observational monocentric study to validate the French MCTQ against the sleep diary for sleep schedules, the Morningness-Eveningness Questionnaire (MEQ) for chronotype, and polysomnography measures. We utilised the mid-sleep point on free days (MSF), adjusted for sleep debt (MSFsc), to gauge morningness/eveningness. The study included 80 participants (average age: 40.9 years, 50% female). The sleep schedules determined by the MCTQ and the sleep diary showed a high correlation. The MSFsc demonstrated a significant correlation with the MEQ, persisting even under sleep constraints such as an alarm on free days. The predictive accuracy was strong for a morning chronotype and moderate for an evening chronotype as assessed using the MEQ. In summary, the French MCTQ is a reliable tool for researchers and clinicians for assessing sleep schedules and chronotype in French-speaking populations. The MSFsc can effectively predict chronotype, even under sleep constraints. However, for the evening chronotype, self-assessment appears to be more accurate. The association with polysomnography measures enriches our understanding of the chronotype at the intersection of behaviour and physiology.

The Bordeaux Sleepiness Scale (BOSS): a new questionnaire to measure sleep-related driving risk.

STUDY OBJECTIVES: Sleepiness is a well-known risk factor for traffic accidents. Our study presents a new questionnaire, the Bordeaux Sleepiness Scale (BOSS), specifically designed to evaluate sleep-related driving risk in patients with sleep disorders. METHODS: The BOSS was designed by gathering data on sociodemographics, sleepiness, driving items, and traffic accident exposure (kilometers driven) in the past year of 293 patients followed for sleep disorders at a French sleep clinic. It was then validated on data from a large population-based cohort of 7,296 highway drivers. Its performance was compared to the Epworth sleepiness scale and to self-reported episodes of severe sleepiness at the wheel. Receiver operating characteristic curves were computed. RESULTS: The sensitivity and specificity of the BOSS (cutoff = 3) to predict sleep-related near-misses or accidents was, respectively, 82% and 74%, with an area under the receiver operating characteristic curve of 0.83. In a cohort of patients and a large population-based cohort, the area under the curve of the BOSS was significantly larger than that of the Epworth sleepiness scale (P < .001). Although the areas under the curve were equivalent between the BOSS and sleepiness at the wheel, the specificity of the BOSS was higher. CONCLUSIONS: The BOSS scale combining exposure (kilometers driven) and self-perception of situational sleepiness provides a simple and reliable evaluation of sleep-related driving risk. This short, specific questionnaire should be promoted as a first-line tool to evaluate the risk of traffic accidents in sleepy patients. CITATION: Philip P, Micoulaud-Franchi J-A, Taillard J, et al. The Bordeaux Sleepiness Scale (BOSS): a new questionnaire to measure sleep-related driving risk. J Clin Sleep Med. 2023;19(5):957-965.

Sleep timing, workplace well-being and mental health in healthcare workers.

INTRODUCTION: Healthcare workers face an elevated risk of burnout, sleep disorders, and mental health issues, potentially stemming from the misalignment of their circadian rhythm due to nonstandard work schedules. This cross-sectional survey aims to examine the connections between sleep timing, workplace well-being (including burnout and absenteeism), and mental health outcomes (specifically depression and poor sleep) in healthcare workers. Additionally, the survey takes into account individual and professional factors, as well as the interaction with work schedules. METHODS: The study encompasses 4,971 healthcare workers from both public and private healthcare facilities in France, including nurses, nursing assistants, and physicians recruited during the third wave of the COVID-19 pandemic. The Maslach Burnout Inventory assesses burnout, the Center for Epidemiologic Studies Depression Scale measures depression, and the Pittsburgh Sleep Quality Index evaluates poor sleep. Sleep timing is categorized into morning, neutral, and evening timing, referred to as midsleep. Multivariate logistic regression analysis is conducted to explore the relationships between sleep timing and burnout, depression, and poor sleep, while adjusting for various factors. RESULTS: The findings reveal that 56.5% of participants experience burnout, 29.8% report depression, and 64.5% report poor sleep. Nurses and nursing assistants exhibit a higher prevalence of poor sleep. Morning sleep timing is associated with burnout among those with fixed schedules and with depression among those with shift schedules. Among physicians, both morning and evening sleep timing are associated with depression, while morning sleep timing is linked to poor sleep across all subgroups. INTERPRETATION: This study suggests that the misalignment between healthcare workers' internal circadian rhythm and their work schedules may contribute to an increased risk of burnout, depression, and poor sleep. Occupational health services and policymakers should recognize the potential for enhancing workplace well-being and mental health outcomes by enabling healthcare workers to maintain sleep schedules that accommodate their needs.

Validity and diagnostic performance of a virtual reality-based supermarket application "MEMOSHOP" for assessing episodic memory in normal and pathological aging.

Objective: MEMOSHOP is a virtual reality (VR)-based supermarket application for assessing episodic memory in aging. The aim of this study was to examine its construct validity against the gold standard paper-and-pencil neuropsychological test for clinical memory assessment in mild cognitive impairment (MCI) in older adults. Methods: Patients with isolated subjective cognitive complaints (SCCs) or MCI were recruited in the Bordeaux Memory Clinic (MEMENTO cohort). Cognitively normal elderly controls were also recruited. MEMOSHOP allows a near-ecological evaluation of episodic memory during a usual daily life activity, i.e. shopping at the supermarket. MEMOSHOP and the gold standard Free and Cued Selective Reminding Test (FCSRT: French adaptation) were administered to all participants to assess episodic memory. Non-parametric tests and receiver operating characteristic curves were computed to compare their performances. Results: Twenty-nine patients (21 females, age = 71 years ±7) and 29 matched controls were evaluated. The performance trends observed with MEMOSHOP and FCSRT on free and cued recall were associated (p < .01) and comparable (p < .0001), without any participants' groups interaction. Although easier than FCSRT in free recall for participants, MEMOSHOP demonstrated better diagnostic performance based on cued recall in isolated SCCs/MCI patients (p < .05). Conclusion: MEMOSHOP demonstrated its reliability and validity for VR-based episodic memory assessment in the early stage of MCI and is potentially of interest for use in memory clinic settings.

Systematic Item Content and Overlap Analysis of Self-Reported Multiple Sleep Disorder Screening Questionnaires in Adults.

Sleep disorders are defined on the basis of diagnostic criteria presented in medical classifications. However, no consensus has emerged on the exact list of operational symptoms that should be systematically investigated in the field of sleep medicine. We propose a systematic analysis of sleep symptoms that figure in a set of self-reported multiple sleep disorder screening questionnaires for adult populations, to identify the content overlap of symptoms that probe the presence of central sleep symptoms, and to highlight the potential level of heterogeneity among sleep disorder questionnaires. The method comprises three steps: (i) the selection of self-reported multiple sleep disorder screening questionnaires; (ii) item extraction and selection; (iii) the extraction of symptoms from items. Frequency of sleep symptoms and content overlap (Jaccard Index) are analyzed. We extracted 469 items that provide 60 different symptoms from 12 questionnaires. Insomnia, somnolence, and sleep-related breathing symptoms were found in all the questionnaires. The mean overlap among all questionnaires evaluated with the Jaccard Index is 0.44, i.e., moderate similarity. Despite limitations related to the selection of questionnaires and the symptom extraction and harmonization, this study underlines the need to standardize sleep symptom contents for sleep medicine in order to enhance the practicability, reliability, and validity of sleep disorder diagnoses.

Association between circadian sleep regulation and cortical gyrification in young and older adults.

The circadian system orchestrates sleep timing and structure and is altered with increasing age. Sleep propensity, and particularly REM sleep is under strong circadian control and has been suggested to play an important role in brain plasticity. In this exploratory study, we assessed whether surface-based brain morphometry indices are associated with circadian sleep regulation and whether this link changes with age. Twenty-nine healthy older (55-82 years; 16 men) and 28 young participants (20-32 years; 13 men) underwent both structural magnetic resonance imaging and a 40-h multiple nap protocol to extract sleep parameters over day and night time. Cortical thickness and gyrification indices were estimated from T1-weighted images acquired during a classical waking day. We observed that REM sleep was significantly modulated over the 24-h cycle in both age groups, with older adults exhibiting an overall reduction in REM sleep modulation compared to young individuals. Interestingly, when taking into account the observed overall age-related reduction in REM sleep throughout the circadian cycle, higher day-night differences in REM sleep were associated with increased cortical gyrification in the right inferior frontal and paracentral regions in older adults. Our results suggest that a more distinctive allocation of REM sleep over the 24-h cycle is associated with regional cortical gyrification in aging, and thereby point towards a protective role of circadian REM sleep regulation for age-related changes in brain organization.

Emotional Exhaustion, a Proxy for Burnout, Is Associated with Sleep Health in French Healthcare Workers without Anxiety or Depressive Symptoms: A Cross-Sectional Study.

Burnout is frequent among healthcare workers, and sleep problems are suspected risk factors. The sleep health framework provides a new approach to the promotion of sleep as a health benefit. The aim of this study was to assess good sleep health in a large sample of healthcare workers and to investigate its relationship with the absence of burnout among healthcare workers while considering anxiety and depressive symptoms. A cross-sectional Internet-based survey of French healthcare workers was conducted in summer 2020, at the end of the first COVID-19 lockdown in France (March to May 2020). Sleep health was assessed using the RU-SATED v2.0 scale (RegUlarity, Satisfaction, Alertness, Timing, Efficiency, Duration). Emotional exhaustion was used as a proxy for overall burnout. Of 1069 participating French healthcare workers, 474 (44.3%) reported good sleep health (RU-SATED > 8) and 143 (13.4%) reported emotional exhaustion. Males and nurses had a lower likelihood of emotional exhaustion than females and physicians, respectively. Good sleep health was associated with a 2.5-fold lower likelihood of emotional exhaustion and associations persisted among healthcare workers without significant anxiety and depressive symptoms. Longitudinal studies are needed to explore the preventive role of sleep health promotion in terms of the reduction in burnout risk.

Better characterizing sleep beliefs for personalized sleep health promotion: the French sleep beliefs scale validation study.

Background: The Sleep Beliefs Scale (SBS) is a well-known tool to design and monitor personalized sleep health promotion at an individual and population level. The lack of an established French version limits the development of effective interventions targeting these populations. Thus, the aim of this study was to validate the French version of the SBS in a representative sample of the general population. Methods: Quota sampling was used to recruit 1,004 participants (18-65 years, mean age: 43 years, 54% of female) who underwent an online survey to complete the SBS, and to assess sleep schedules, sleep quality and disorders, and mental health. Cronbach's α coefficient, confirmatory factor analysis, item-internal consistency (IIC), and item discriminant validity (IDV) of the SBS were computed to assess internal validity while bivariate associations with sleep schedules, sleep quality and disorders, and mental health were used to assess external convergent and discriminant validity. Results: The mean score on the SBS was 12.3 ± 4.9. Item 19 ("Quiet & Dark") showed the highest rate of correct answers (n = 801, 79.8%), while item 20 ("Recovering sleep") showed the lowest rate of correct answers (n = 246, 24.5%). Overall, the SBS showed satisfactory internal consistency (α = 0.87) and confirmed the three-factor structure proposed by the original study. All items were found consistent (IIC > 0.4) and discriminant (IIC > IDV) except for item 20 ("recovering lost sleep by sleeping for a long time"). Females, older participants, and subjects with short time-in-bed, poor sleep quality, insomnia, and circadian rhythm disorder had higher SBS scores while participants with depressive symptoms had lower SBS scores. Conclusion: We successfully translated and validated the French version of the SBS in a representative sample, making it a reliable instrument for researchers and clinicians to assess and target sleep beliefs. Correct answers vary from 25 to 80% which underlines the importance of continuing sleep health promotion campaigns by targeting poorly understood behaviors. Our findings also shed light on the fickleness of beliefs that are prone to vary within individuals across time, in step with societal changes. Several associated factors were identified, thus contributing to our understanding of sleep beliefs and offering insights for personalized approaches to enhance sleep health and overall well-being.

In-car countermeasures open window and music revisited on the real road: popular but hardly effective against driver sleepiness.

This study investigated the effects of two very commonly used countermeasures against driver sleepiness, opening the window and listening to music, on subjective and physiological sleepiness measures during real road driving. In total, 24 individuals participated in the study. Sixteen participants received intermittent 10-min intervals of: (i) open window (2 cm opened); and (ii) listening to music, during both day and night driving on an open motorway. Both subjective sleepiness and physiological sleepiness (blink duration) was estimated to be significantly reduced when subjects listened to music, but the effect was only minor compared with the pronounced effects of night driving and driving duration. Open window had no attenuating effect on either sleepiness measure. No significant long-term effects beyond the actual countermeasure application intervals occurred, as shown by comparison to the control group (n = 8). Thus, despite their popularity, opening the window and listening to music cannot be recommended as sole countermeasures against driver sleepiness.

Circadian misalignment is associated with Covid-19 infection.

BACKGROUND: Circadian system contributes to the regulation of inflammatory processes, but the role of circadian misalignment as a risk factor for contracting Covid-19 has up to now been poorly studied. The aim of this study was to explore the relationship between circadian misalignment (chronic disturbance of the circadian system) and the risk of Covid-19 infection in a population of subjects suspected of contact or infection with SARS-CoV-2. METHODS: Cross-sectional single-center study conducted during a period without lockdown in winter 2021. Recruitment took place in a Covid-19 outpatient testing center. Subjects between 18 and 45 years old were included whether they were symptomatic or not, healthcare workers or not, in contact with a Covid-19 case or not. To determine social jetlag, a proxy of circadian misalignment, they were asked about their usual sleep-wake behaviors. Usual sleep duration and sleep-wake timing were explored on workdays and free days. Social jetlag was defined as at least 2 h shift of circadian alignment (defined as the difference between mid-sleep on workdays and mid-sleep on free days, mid-sleep as the median between bedtime and rise time). RESULTS: One thousand fourteen subjects were included (sampling rate: 10.8%, 39% men, mean age 28 ± 8) with 56 subjects positive for Covid-19 (positivity rate: 5.5%). Usual mean sleep duration was equivalent in both groups (7h47 versus 7h49, p = 0.733). Social jetlag greater than 2 h comprised 33.3% of subjects in the Covid-19 group versus 20.6% in the control group (p = 0.026). After adjustment on age, gender, BMI and work schedules, subjects presenting with social jetlag greater than 2 h had a 2.07-fold higher likelihood to test positive than subjects who had identical sleep-wake timing on workdays and free days (OR = 2.07, 95%CI = [1.12-3.80], p = 0.024). CONCLUSION: Circadian misalignment not only is present in subjects infected by Covid-19 but could also be responsible for a higher likelihood of being infected. The chronobiological impact on the immune system or a higher likelihood of being exposed to social contacts during nocturnal activities could explain our findings, which need to be confirmed in a future large cohort study. Regular sleep-wake timing could ultimately become a target for preventing Covid-19 infection.

A Systematic Review of Sleep-Wake Disorder Diagnostic Criteria Reliability Studies.

The aim of this article is to provide a systematic review of reliability studies of the sleep-wake disorder diagnostic criteria of the international classifications used in sleep medicine. Electronic databases (ubMed (1946-2021) and Web of Science (-2021)) were searched up to December 2021 for studies computing the Cohen's kappa coefficient of diagnostic criteria for the main sleep-wake disorder categories described in the principal classifications. Cohen's kappa coefficients were extracted for each main sleep-wake disorder category, for each classification subtype, and for the different types of methods used to test the degree of agreement about a diagnosis. The database search identified 383 studies. Fifteen studies were analyzed in this systematic review. Insomnia disorder (10/15) and parasomnia disorder (7/15) diagnostic criteria were the most studied. The reliability of all sleep-wake disorders presented a Cohen's kappa with substantial agreement (Cohen's kappa mean = 0.66). The two main reliability methods identified were "test-retest reliability" (11/15), principally used for International Classification of Sleep Disorders (ICSD), and "joint interrater reliability" (4/15), principally used for Diagnostic and Statistical Manual of Mental Disorders (DSM) subtype diagnostic criteria, in particularl, the DSM-5. The implications in terms of the design of the methods used to test the degree of agreement about a diagnosis in sleep medicine are discussed.