Regular Sleep Schedule Research Articles

Sleep Disturbance and Self-management in Adults With Subarachnoid Hemorrhage: A Qualitative Study.

Subarachnoid hemorrhage (SAH) survivors often experience sleep disturbances. Little is known about sleep-management practices used to improve their sleep. The purpose of this qualitative study was to explore interest in and engagement with self-management practices to promote sleep health in SAH survivors. We conducted a cross-sectional qualitative study using semi-structured interviews with a convenience sample of 30 SAH survivors recruited from a university hospital. We conducted content analysis of interview transcripts. Three themes and 15 subcategories were identified: (1) sleep disturbances (difficulties falling asleep, wake after sleep onset, daytime sleepiness, too much or insufficient sleep, and poor sleep quality); (2) sleep-management practices (exercise, regular sleep schedule, relaxation, keeping busy and staying active, changing beverage intake, taking supplements, taking medications, recharging energy, and barriers to sleep management); and (3) consulting with healthcare providers (discussing sleep problems with healthcare providers). Self-management strategies focusing on health-promoting behaviors may improve SAH survivors' sleep health.

Too Jittery to Sleep? Temporal Associations of Actigraphic Sleep and Caffeine in Adolescents.

Caffeine consumption has been linked to poor sleep health in adolescents, but it is unknown whether poor sleep predicts caffeine consumption, and/or whether caffeine consumption predicts poor sleep, particularly when sleep is measured objectively. Data were collected from a micro-longitudinal sub-study of the age 15 wave of the Fragile Families and Child Wellbeing Study (n = 589). Adolescents wore an actigraphy device and completed daily surveys for ~1 week. Daily surveys assessed subjective sleep quality and caffeinated beverage consumption (0 = no caffeine, 1 = any caffeine). Separate mixed models assessed whether actigraphy-measured sleep duration, timing, maintenance efficiency, and subjective quality predicted next-day caffeinated beverage consumption within and between adolescents. Variability (standard deviation) of sleep duration and timing, sleep regularity index, and social jetlag were tested as additional between-person predictors. Lagged models tested whether daily caffeinated beverage consumption predicted sleep that night (n = 458). Adolescents with more variable sleep duration and midpoint had higher average odds of consuming caffeinated beverages compared to others. After adolescents consumed ≥1 caffeinated beverage, they had later sleep onset that night and wake time the next morning than usual versus when they did not consume caffeine. Curbing caffeinated beverage consumption may aid in the maintenance of regular sleep schedules and advance sleep timing in adolescents.

The Global Council on Brain Health: Tailoring brain health guidance for the pandemic era

AbstractBackgroundThe Global Council on Brain Health (GCBH) recognizes people across the globe are interested in learning what they can do to maintain their brain health as they cope with the pandemic. With growing evidence that COVID‐19 harms brain health, the GCBH determined it was important to inform people about the impact and what if anything might be done about it.MethodThe GCBH has updated recommendations relevant to patient and caregiver advice to reflect the current challenges of living in a pandemic. This presentation will explore both the direct and indirect ways the virus impacts brain health and offers recommendations based upon the current state of the science on how to try to avoid the harms the pandemic poses. The GCBH considered which of their previous brain health recommendations they could make to foster brain health resiliency during the pandemic.ResultRecommendations included: stay physically active, eat a healthy diet, stay socially connected, maintain a regular sleep schedule, stimulate your brain, take care of your mental health, pay attention to signs of ‘brain fog’, monitor changes in neurological health, and don’t put off necessary medical appointments.ConclusionThis presentation will discuss the approach taken and lessons learned in adapting several years of brain health guidance for the COVID era. Living through this pandemic, even without infection, can adversely impact mental well‐being and ultimately brain health. Many people have been forced to change rituals and routines with substantially reduced social interaction under guidelines designed to reduce the spread of the virus. Moreover, COVID has had an undeniably huge negative impact on people living with dementia and the long‐term consequences will be topic of research for years to come.

Circadian preference and sleep quality in healthy controls and psychiatric inpatients with major depressive disorder – An actigraphy study incorporating morning and evening mood assessments

ABSTRACT Major depressive disorder (MDD) is frequently accompanied by sleep disturbance. Regarding diurnal preference (chronotype), sleep problems and low mood have been associated with evening orientation. Considering diurnal preference, we investigated subjective restorative value of sleep and actigraphy sleep parameters together with mood assessments twice a day, i.e. in the morning and evening, during weekdays and weekends in MDD psychiatric inpatients and healthy controls (HCs). The restorative value of sleep was higher during the weekend in HC, and bedtimes and risetimes were delayed during the weekend compared to weekdays in HC and MDD. Morning mood affected subjective sleep ratings in both groups, while association with symptom severity (BDI) in MDD remained insignificant. In HC, better evening mood was associated with later bedtimes. Regarding the chronotype in HC, evening orientation was associated with relatively low restorative value of sleep during weekdays, and morning orientation was associated with relatively higher actigraphy sleep efficiency during weekdays compared to weekend. In MDD, an association of evening orientation with later rise times could be observed, while no chronotype dependent effect emerged regarding the restorative value of sleep or sleep efficiency. Our results emphasize that research on sleep in MDD should incorporate weekdays as well as weekends, chronotype assessment, and measures of morning and evening mood, as these can be associated with ratings of the subjective restorative value of sleep (i.e. in our study, better morning mood was associated with higher restorative values), but also with behavioral sleep parameters (i.e. in our study, more positive evening mood was associated with later bedtimes). Potentially, the restorative value of sleep in MDD evening types can be improved by maintaining a regular sleep schedule, which needs to be investigated in an experimental design.

Sleep, Dreams, and Nightmares During the COVID-19 Pandemic.

The COVID-19 pandemic has affected the sleep and dreams of many individuals. Some have experienced improvements, while others have had more complaints. The changes to daily life such as working from home and spending more time indoors in confinement may have disturbed the circadian rhythms of some individuals. There were many reports of a shift towards a later bedtime during the pandemic, with several studies showing that in general, females experienced worse sleep than males, including more nighttime awakenings and nightmares. Increased dream and nightmare frequency during the pandemic has been shown in multiple studies. It has been postulated that because dreams are often guided by the dominant emotional state, that dreams and nightmares related to pandemic themes are a result of specific stressors related to COVID-19. Those experiencing unwanted sleep disturbances and nightmares could stand to benefit from mindfulness and relaxation practices that can ease stress and anxiety before bedtime. Striving to maintain a regular sleep schedule and enhance exposure to daylight-particularly during the first half of the day-may also be helpful.

Sleep and circadian rhythm characteristics in individuals from the general population during the French COVID-19 full lockdown.

SummaryThe full 2‐month lockdown to fight the coronavirus disease 2019 (COVID‐19) pandemic in 2020 led to substantial disruption of daily life and routines. The present study aimed to comprehensively identify the lockdown’s effects on sleep, daily rhythms and emotions of the French population. A survey was published online during the last week of the 2‐month full lockdown and 1,627 individuals completed the online survey. The survey was self‐administered and included standardised questionnaires. Sleep schedules were delayed during lockdown in more than half of the participants. New severe delayed sleep phase affected 10% of participants with sleep schedules delayed by ≥3 hr during the lockdown compared to before. A significant decrease in exposure to morning (p < 0.001) and evening natural light (p < 0.001), a significant increase in screen exposure time (with a significant screen exposure >3 hr during the evening for 45% of the participants during lockdown versus 18% before lockdown, p < 0.001), an increase in substance use for one‐quarter of participants, a poorer sleep quality in 56% of participants, and less regular sleep schedules in 48% of participants were observed. We also found a poorer sleep quality in women than men during lockdown (p = 0.004). The French full lockdown had a severe impact on sleep quality, sleep–wake rhythms, and sleep behaviours. The implementation of public health strategies for the prevention and care of sleep–wake cycles during lockdown are therefore essential.

Effects of Acute Sleep Deprivation on Working Memory Capacity in Undergraduate Students

Sleep is a necessary staple in our everyday lives but with advancements in society and an increase in day to day commitments it feels as though there is not enough time in the day. One of the first things to be forsaken in the hopes of maintaining a work schedule or routine is sleep. While the lack of sleep is disproportionate in most demographics, in university students in particular, a lack of sleep is a common, consistent, and necessary plague. Students can be under the impression that the effects of sleep deprivation have mostly long-term repercussions; however, prior literature has indicated that sleep deprivation impacts not just long-term consolidation but also significantly affects memory in the short-term, specifically the working memory (Xie et al. 2019; Chee et al., 2006). In this investigation, we seek to understand the effects that acute sleep deprivation has on the working memory capacity of individuals using a 2-back spatial test. A sample of convenience of upper-class undergraduate students was chosen and the participants were asked to take a specific 2-back spatial test - twice on a day that they subjectively felt as having a regular sleep schedule and twice on a day that they subjectively felt as having sleep deprivation. The team predicted that working memory 2-back task scores will be adversely affected by sleep deprivation. While there was a statistically significant difference in the working memory scores on the full sample level, this was not reflected on the individual level. This indicates that the effects of sleep deprivation are not generalizable to a full population and that they must be reviewed on a case-by-case basis. Furthermore, since greater variation was observed in the sleep deprived scores in all individuals, it implies that sleep deprivation may indirectly affect the consistency of working memory by affecting attention span and concentration.

087 Gender differences in attitudes towards sleep moderate sleep hygiene behaviors

Abstract Introduction Attitudes towards sleep have been shown to be a predictor for sleep hygiene. Sleep hygiene is the set of behaviors and conditions that promote optimal sleep, such as avoiding arousing nighttime activities, avoiding eating too close before bed, having a dark and quiet bedroom, and having a regular sleep schedule. Previous literature indicates that there are gender differences in health attitudes. This study examined whether gender differences in sleep attitudes may explain differences in sleep hygiene. Methods A sample of 172 (101 males, 71 females) individuals completed surveys through Amazon’s Mechanical Turk. Sleep attitudes were assessed using the Charlotte Attitudes Towards Sleep Scale (CATS; Peach &amp; Gaultney, 2017). Sleep hygiene was measured using the Sleep Hygiene Practice Scale (SHPS; Lin et al; 2007; Yang et al., 2010). Males were dummy coded as 0. Other data were collected surrounding sleep outcomes, health behaviors, and demographics. Linear regression analyses were ran to examine the impact of Sleep attitudes, gender, and an interaction term on each subscale of the SHPS. Results Sleep attitudes significantly predicted each of the components of the SHPS: arousal, eating, environment, and time (b = -3.44, -2.93, -3.80, -3.04; p&amp;lt;.01 for each). Gender significantly predicted sleep hygiene behaviors for eating (b = -10.35, p&amp;lt;.05) and environment (b = -15.40, p&amp;lt;.05) only. The interaction term also significantly predicted sleep hygiene eating behaviors (b = 1.70 p&amp;lt;.05) and environmental conditions (b = 2.91, p&amp;lt;.05). These findings suggest that more favorable sleep attitudes lead to better sleep hygiene behaviors, and women tend to have better eating and environment related sleep hygiene behaviors. Graphs of the interactions indicated males’ sleep attitudes associated with greater differences in sleep hygiene practices, in that positive sleep attitudes predicted better eating and environment elements of sleep hygiene. Conclusion This exploratory research suggested that men’s sleep-related behaviors may be more sensitive to the role of sleep attitudes. Future research should explore causes for gender differences in sleep attitudes and seek ways to improve behaviors and outcomes that are most relevant for specific demographic groups. Support (if any) Psychological Sciences department funding

Associations of diarised sleep onset time, period and duration with total and central adiposity in a biethnic sample of young children: the Born in Bradford observational cohort study

ObjectivesTo investigate associations of parent-reported sleep characteristics with adiposity levels in a biethnic sample of young children.DesignA cross-sectional observational study.SettingThe Born in Bradford 1000 study, UK.ParticipantsChildren aged approximately 18 months...

The associations between sleep situations and mental health among Chinese adolescents: A longitudinal study

ObjectiveFew studies are conducted to explore the longitudinal relationships between sleep situations and mental health among adolecents. This study aimed to explore the sleep situations (ie, sleep habits and sleep problems) among Chinese adolescents and the longitudinal associations between sleep situations and mental disorder symptoms (ie, depressive and anxiety symptoms). MethodsThis longitudinal study included 1957 high school students from ten schools in Guangzhou in January 2019, with 1836 students contributing valid data at a one-year follow-up (retention rate: 93.9%). Data of depressive and anxiety symptoms, sleep habits, and sleep problems were collected using a self-reported questionnaire. ResultsThe current study found that over half of the adolescents did not reach the recommended 8-h sleep-time on weekdays (63.3%). Short sleep duration, especially on weekdays, was significantly associated with subsequent depressive (AOR = 0.86, 95%CI: 0.80–0.92) and anxiety symptoms (AOR = 0.86, 95%CI: 0.77–0.96). In addition, longer weekday-weekend catch-up sleep and more sleep problems were risk factors of depressive and anxiety symptoms. ConclusionsThe health effects of insufficient sleep and suboptimal sleep quality on adolescents should not be neglected. Our longitudinal research showed that adolescents would demonstrate severer depressive and anxiety symptoms if lacking of a healthy sleeping practice. A regular sleep schedule and close attention to adolescents’ mental disorders are highly recommended.

Sleep diary- and actigraphy-derived sleep parameters of 8-hour fast-rotating shift work nurses: A prospective descriptive study

BackgroundGiven the harmful effects of night shifts and rotating schedules on nurses’ sleep and work performance, shift nurses’ sleep patterns have been a research concern. Actigraphy involves acquisition of data using a movement sensor worn continuously on the nondominant wrist, typically for a week or more. Although actigraphy provides objective and accurate sleep data, sleep diaries have been a practical alternative. However, there is a lack of research on the agreement and consistency between the two methods of measuring sleep for shift work nurses. In addition, differences in sleep patterns by shift types among 8-hour fast-rotating shift work nurses has not yet been examined. ObjectivesTo evaluate the agreement between the sleep diary and actigraphy methods for sleep assessment, and to compare sleep parameters of 8-hour fast-rotating shift work nurses according to shift type. DesignDescriptive and prospective study design. SettingsTwo tertiary hospitals in Seoul, South Korea. ParticipantsA total of 94 shift work nurses who wore actigraphy along with completing a sleep diary. MethodsSubjective and objective sleep parameters were recorded during a two-week period in a sleep diary and actigraphy, respectively. Bland-Altman plots and intraclass correlation coefficients were used to analyze the agreement between the two methods. Sleep parameters according to shift type were compared using the Kruskal–Wallis and Mann–Whitney U tests. ResultsGood agreement was observed between the sleep diary and the actigraphy data for total sleep time (intraclass correlation coefficients = 0.765 or 0.858) and variability in sleep time (intraclass correlation coefficients = 0.838). When compared to the actigraphy data, diary-derived data were overestimated by 41–45 min for total sleep time and 0.4% for variability in sleep time. There was a difference of 2–3 h of sleep quantity by shift type: 5.3–5.8 h for day shifts and 7.1–8.4 h for night shifts. ConclusionsA sleep diary can function as an acceptable alternative to actigraphy for measuring shift work nurses’ sleep patterns, specifically total sleep time and variability in sleep time. Given the high variability in sleep among shift work nurses, both personal and organizational efforts are required. Nurses should monitor their sleep quantity and develop their own regular sleep schedules to fit their work schedules. Hospitals should establish healthy schedules for nurses to guarantee sufficient sleep hours before work. Future research on shift work nurses’ sleep should examine fluctuations in sleep duration.

Sleep Variability Is A Predictor Of Peripheral Vascular Function In Apparently Healthy Undergraduate College Students

Experimental studies suggest that highly variable sleep-wake patterns may impair vascular function, suggesting a potential mechanism for the increased risk of cardiovascular (CV) diseases seen in shift workers and those with sleep disorders. However, it is unclear if naturalistic, day-to-day variability in sleep-wake patterns of generally healthy individuals poses a risk to vascular function. PURPOSE: To examine the association between sleep variability (SLV) and vascular function in undergraduate college students. METHODS: SLV metrics were estimated in 39 healthy undergraduate students (20 ±0.2 years) using wrist actigraphy for 14 days and nights. Sleep timing was defined by sleep midpoint (halfway point between sleep onset and wake onset). Sleep timing variability (STV) was then quantified as the standard deviation (SD) of sleep midpoint, and sleep duration variability (SDV) as the SD of sleep duration across 14 days. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). Peripheral vascular function was indexed as the magnitude of hyperemia in response to passive leg movement (PLM) and was performed immediately following the end of sleep monitoring. Blood velocity and femoral artery diameter were measured via Doppler ultrasound. RESULTS: In a linear regression model adjusting for sex and body mass, SDV predicted peak leg blood flow (LBF) (β=-0.49, p<0.01), change in LBF from baseline to peak (β=-0.50, p<0.01), and LBF area under the curve (AUC) (β=-0.57, p<0.01) during PLM. Associations remained significant when the model included PSQI score (all p<0.01). Similarly, models adjusting for sex and mass found that STV predicted LBF AUC (β=-0.30, p=0.05). CONCLUSION: In adjusted models, greater SLV is associated with less optimal peripheral vascular function in healthy college students. These data support the growing body of literature suggesting that regular sleep schedules may be important for CV health, even in otherwise healthy young adults. Supported, in part, by NIH P20GM113125.

Sleep health and predicted cognitive effectiveness of nurses working 12-hour shifts: an observational study

BackgroundDue to the 24hr nature of society, shift work has become an integral part of many industries. Within the literature there exists an abundance of evidence linking shift work-related sleep restriction and fatigue with errors, accidents, and adverse long-term health outcomes. ObjectiveThe study goal was to physiologically measure sleep patterns and predicted cognitive decline of nurses working both 12hr day and night shifts to address the growing concern about sleep restriction among healthcare workers. DesignThis study presents the results of a quasi-experimental, mixed between-within design where the sleep of 12hr day and night shift nurses was measured using ReadiBand wrist actigraphs. The between groups component was comprised of day v. night shift nurses. The within groups component was comprised of two separate measurement periods for each nurse—once for three consecutive days while they were working shifts (on duty) and once for three consecutive days off work (off duty). SettingParticipants wore the wrist actigraph at home and in the hospital, and were instructed to adhere to their regular sleep schedule. ParticipantsParticipants were recruited from two hospitals in Washington State (n=90). Participants were 48 night- and 42 day-shift nurses. All participants worked 12-hour shifts. MethodsSleep was measured using ReadiBand wrist actigraphs, which are licensed with the Sleep, Activity, Fatigue, and Task Effectiveness (SAFTEtm) Alertness Score model, a biomathematical model that predicts cognitive effectiveness based on sleep/wake schedule. ReadiBands also calculate sleep quantity, sleep efficiency, and sleep latency. Results were analysed in SPSS (v26) through multilevel modelling. ResultsDifferences were observed in sleep quantity, efficiency, and latency based on shift type (day vs. night) and shift duty (on vs. off). The most extreme differences, however, were noted in cognitive effectiveness (SAFTEtm), whereby night shift nurses experienced substantial decline—frequently into the “high risk” zone—throughout their shifts compared to day shift nurses. ConclusionsThe present study identifies sleep characteristics that differ between day and night nurses working 12-hour shifts using objective measurements of sleep. Biomathematical modelling can offer a novel method to estimate hours of greatest cognitive decline, and have implications for policy around shift duration, timing, and overtime allocation.

1140 Sleep Disturbances, Lifestyle, And Self-Management In Adults With Subarachnoid Hemorrhage

Abstract Introduction Subarachnoid hemorrhage (SAH) survivors often suffer sleep disturbances. Self-management strategies focusing on lifestyle changes and health-promoting behaviors may improve sleep in SAH survivors. Few studies have examined sleep in SAH survivors, and little is known about sleep management practices used to improve their sleep. The purposes of this study were to: 1) describe the prevalence of sleep disturbances using subjective and objective sleep measures, and 2) explore interest in and engagement with self-management practices to promote sleep health in SAH survivors. Methods We conducted a cross-sectional study with a convenience sample of 30 SAH survivors recruited from a university hospital. We assessed sleep quality using the Pittsburgh Sleep Quality Index (PSQI), daytime sleepiness using the Epworth Sleepiness Scale (ESS), and objective sleep using wrist actigraphy. We conducted content analysis of semi-structured interviews, with two authors each coding sleep disturbances and self-management practices addressing sleep. Results Seventy-three percent of SAH survivors reported poor sleep quality (PSQI &amp;gt; 5) and 27% had daytime sleepiness (ESS &amp;gt; 10). Actigraphy analysis indicated that 41% of SAH survivors slept less than 7 hours or more than 9 hours. Interview content analyses suggested 3 themes and 15 sub-categories: 1) Sleep disturbances (difficulties in falling asleep, wake after sleep onset, daytime sleepiness, too much or insufficient sleep, and poor sleep quality), 2) Sleep management practices (exercise, regular sleep schedule, relaxation, keeping busy and staying active, changing beverage intake, taking supplements, taking medication, recharging energy, and barriers to sleep management), and 3) Healthcare providers (discussing sleep problems with health care providers). Conclusion Sleep disturbances are highly prevalent and an urgent need exists to focus on improving sleep in SAH survivors. Developing tailored interventions that incorporate self-management and lifestyle change would be a critical next step to improve sleep and promote health in this at-risk population. Support This research was supported by grants from the National Institutes of Health/National Institute of Nursing Research (K23 NR017404), University of Washington Institute of Translational Health Science Translational Research Scholars Program (UL1 TR000423), and University of Washington School of Nursing Research and Intramural Funding Program.

Less physical activity and more varied and disrupted sleep is associated with a less favorable metabolic profile in adolescents.

BackgroundSleep and physical activity are modifiable behaviors that play an important role in preventing overweight, obesity, and metabolic health problems. Studies of the association between concurrent objective measures of sleep, physical activity, and metabolic risk factors among adolescents are limited.ObjectiveThe aim of the study was to examine the association between metabolic risk factors and objectively measured school day physical activity and sleep duration, quality, onset, and variability in adolescents.Materials and methodsWe measured one school week of free-living sleep and physical activity with wrist actigraphy in 252 adolescents (146 girls), aged 15.8±0.3 years. Metabolic risk factors included body mass index, waist circumference, total body and trunk fat percentage, resting blood pressure, and fasting glucose and insulin levels. Multiple linear regression adjusted for sex, parental education, and day length was used to assess associations between metabolic risk factors and sleep and activity parameters.ResultsOn average, participants went to bed at 00:22±0.88 hours and slept 6.2±0.7 hours/night, with 0.83±0.36 hours of awakenings/night. However, night-to-night variability in sleep duration was considerable (mean ± interquartile range) 0.75±0.55 hours) and bedtime (0.64±0.53 hours) respectively. Neither average sleep duration nor mean bedtime was associated with any metabolic risk factors. However, greater night-to-night variability in sleep duration and bedtime was associated with higher total body and trunk fat percentage, and less physical activity was associated with higher trunk fat percentage and insulin levels.ConclusionGreater nightly variation in sleep duration and in bedtime and less physical activity were associated with a less favorable metabolic profile in adolescents. These findings support the idea that, along with an adequate amount of physical activity, a regular sleep schedule is important for the metabolic health of adolescents.

Fatigue in Collegiate Flight Training

Fatigue-related problems are not new in the aviation industry and have been a contributing factor to more than one-fifth of all aviation accidents. Using an online survey instrument, this exploratory study investigated how 138 collegiate flight students interact with fatigue during their flight training. Overall, students recognize they are fatigued and that it has a negative impact on their flight training. Many of the students identify the proper strategic adjustments that they need to make to manage fatigue, such as reducing workload, getting more sleep, and keeping a regular sleep schedule. However, they do not seem to be making those adjustments. They indicate that they lack enough quality sleep, have high workloads, and do not keep a regular sleep schedule. Findings from this study are consistent with recent flight training studies and can assist the collegiate flight training community in the management of student fatigue.

Preschool children's eating and sleeping habits: late rising and brunch on weekends is related to several physical and mental symptoms

ObjectiveAs the relationships of sleep-wake schedule and mealtime with children's behaviors have not often been studied together, we investigated the relationships of these lifestyles variables with preschool children's well-being. MethodsUsing a network survey, we investigated several lifestyle variables of 1000 families with preschool children. ResultsOur previous articles reported that preschool children's bedtime was delayed by the compulsory nap routine in Japanese nursery schools. The present study revealed similar results. We conducted a cluster analysis with children's meal and sleep time data, which yielded five different lifestyle groups. Cluster 1 was characterized by “extremely late and irregular” meal and sleep times; similar to Cluster 1, Cluster 2 was a “late and irregular” lifestyle group. Cluster 3 was a “mildly late” lifestyle group. Cluster 4 was an “early bird and regular lifestyle” group, and Cluster 5 resembled the “early bird and regular lifestyle” group on weekdays, but was “late and irregular on weekends.” It was found that the later and more irregular the children's meal and sleep times, the worse their physical and mental condition. Even for Cluster 5, the children who had early and regular meal and sleep times on weekdays, getting up and having breakfast late and irregularly on weekends showed worse physical and mental conditions. These problematic symptoms observed in children with late meal and sleep times on weekends might be partly associated with the irregularity of their habits and partly associated with delayed mealtime, especially for breakfast (brunch). ConclusionA stable lifestyle, including a regular sleep and wake schedule and mealtime, is important for preschool children's mental and physical health.

Hypothalamic-pituitary-adrenal axis differentially responses to morning and evening psychological stress in healthy subjects.

AimThe hypothalamic‐pituitary‐adrenal (HPA) axis responds to changing environmental demands including psychological stressors. The aim of the present study was to assess whether the time of day effects on the acute response of HPA axis activity to acute psychological stress.MethodWe studied 27 healthy young subjects. The subjects were participated two experiments as follows. In the first experiment, subjects were instructed to keep their regular sleep schedule for 2 weeks which were measured by using a wrist‐worn activity monitor. Afterward, to evaluate a diurnal rhythm of salivary cortisol, eight saliva samples were collected during waking period every 2 hours from when the subjects woke up. In the second experiment, the subjects were randomly assigned to two groups. The Trier Social Stress Test (TSST) was performed either in the morning (n = 14) or in the evening (n = 13). We measured diurnal rhythm of salivary cortisol and stress response of salivary cortisol and heart rate by the TSST. Morning and evening tests were started at 2 hours and 10 hours after woke up, respectively.ResultsAll subjects showed a normal diurnal rhythm of salivary cortisol concentration, with a peak in the morning immediately after awaking and a minimum in the evening. The salivary cortisol response after the TSST was significantly increased from the prestress level in the morning but not in the evening.ConclusionThe HPA response to acute psychological stress was more pronounced in the morning than in the evening, correlating with the circadian regulation of cortisol synthesis.

The Impact of a Randomized Sleep Education Intervention for College Students.

Sleep deprivation can impair attention, mood, and performance; however, few effective sleep education programs are available. The aim of this study was to assess the effect of a sleep education website, Sleep to Stay Awake (sleeptostayawake.org), on sleep behaviors of college students. College students (age 18 years or older) attending a public Midwestern university were randomized to control or intervention groups. All subjects completed baseline surveys that included demographics, Pittsburgh Sleep Quality Index, Patient Health Questionnaire, sleep knowledge, and measures of sleepiness and circadian rhythm. The intervention group then undertook the online intervention. Surveys were repeated at 1 week and at 8 weeks. Students who participated included 295 controls and 254 intervention subjects. The mean age was 21.9 ± 4.1 years and 41.7% were male. Survey results at 8 weeks showed that more intervention subjects reported improved sleep behaviors (50.3% versus 39.5%, P = .04). Intervention subjects were more likely to stop electronics use earlier (odds ratio [95% confidence interval] = 1.5 [1.0-2.4]), keep a more regular sleep schedule (1.6 [1.06-2.4]), have an earlier weekday rise time (2.4 [1.3-4.4]), and have a lower likelihood of insufficient sleep prior to examinations (0.46 [0.28-0.76]). The intervention group had improvement in mean sleep quality (odds ratio = 5.8 versus 6.6, P < .001) and depression scores (odds ratio = 4.6 versus 5.6, P = .03). No significant differences were found in the other measures. A brief and personalized online sleep education intervention improved sleep behaviors, sleep quality, and depressions scores. This novel approach to address sleep deprivation, poor sleep habits, and mood among college students may offer an effective and inexpensive remedy.

Associations between chronotype, road accidents and polymorphisms in genes linked with biological clock and dopaminergic system

Our study aimed to investigate the possible associations between chronotype parameters, traffic accident history and single nucleotide polymorphisms (SNPs) in a number of genes: RORA (rs1159814), CLOCK (rs12649507), PER3 (rs2640909), NPSR1 (rs324981), NPAS2 (rs4851377), DRD3 (rs6280), SLC6A3 (rs6347), DBH (rs1611125). We have studied 303 professional bus drivers working on rolling shifts in the Moscow region who had a recorded history of road accidents. The studied group was genotyped on selected SNPs and has filled out two chronotype questionnaires: MCTQ and shortened SWPAQ (Putilov A.A, 2014). A mixed chronotype with high levels of morning and evening alertness prevailed in the group. A prominent social jetlag caused by shift work was found. For SNP in PER3 gene there was an association with morning activation. SNP in CLOCK gene was associated with social jetlag and the risk to cause a crash. Minor alleles of SNPs in NPSR1and SLC6A3 correlated with later chronotype and increased risk of a road accident. We suppose that these polymorphisms may be amongst the genetic factors connecting chronotype and road accident risk.