Circadian Disorders, Insomnia, and Parasomnias

Circadian rhythm disorders have misalignment between the desired sleep schedule and the circadian (24-hour) sleep-wake rhythm. Many persons experience this misalignment with jet lag. Other common circadian rhythm disorders include delayed sleep-phase disorder, advanced sleep-phase disorder, and shift-work sleep disorder. Insomnia is one of the most common medical concerns, and its prevalence increases with age. Patients may have difficulty initiating sleep or maintaining sleep and generally have a poor quality of sleep. Causes of insomnia are multifactorial.

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.

Psychological Status Associated With Low Quality of Life in School-Age Children With Neurodevelopmental Disorders During COVID-19 Stay-At-Home Period

Background: This study seeks to ascertain how the COVID-19 stay-at-home period has affected the quality of life (QOL) of children with neurodevelopmental disorders (NDDs) who had experienced sleep schedules alteration and clarify what psychological status predicted low QOL in children with and without altered sleep patterns.Materials and Methods: Study participants were 86 children between 8 and 17 years of age (mean age, 11.7 years; 70 boys, 16 girls; mean intellectual quotient, 83.6). QOL was evaluated using the self-assessment KINDLR. Participants answered questions regarding depression and anxiety on a visual analog scale (VAS) for temporary mood. Their parents answered questionnaires regarding their maladaptive behaviors and differences in sleep patterns before and during the COVID-19 pandemic. The student's t-test was performed to examine the presence or absence of sleep changes in the children, which affected QOL, temporary mood, and maladaptive behaviors. Multiple or simple linear regression analyses were also performed to identify the psychogenic factors that significantly affected decreased QOL for each group with and without changes in sleep schedule.Results: During the COVID-19 stay-at-home period, 46.5% of participants experienced changes in sleep patterns. These changes were associated with decreased QOL as well as internalized symptoms. The decreased QOL of children with sleep patterns changed was predicted by a high level of depression. In addition, low QOL in children with unchanged sleep patterns was predicted by a high level of depression and low current mood status.Conclusions: Almost half of the participants experienced a poor sleep schedule during the stay-at-home period. These alterations in sleep patterns were associated with a low QOL. The QOL of children with a stable life schedule was affected not only by depressive tendencies but also temporary moods. Therefore, they need to live a fulfilling life to maintain their QOL. However, the QOL of children with poor sleep patterns was affected only by depressive tendencies. Hence, clinicians need to ensure that children with NDDs are well-diagnosed with depression and treated for sleep problems.

BEHAVIORAL SLEEP PROBLEMS IN CHILDREN (BEHAVIORAL INSOMNIA) AND EFFECTIVE METHODS OF THEIR MANAGEMENT

Sleep problems with behavioral origins occur in 20 to 30 percent of children and are especially common in children with medical, neurodevelopmental, or psychiatric disorders. Insomnia related to learned sleep onset associations is most common in infants and toddlers and is characterized by prolonged night waking, requiring parental intervention to restore sleep. It occurs when the child learns to associate falling asleep with specific experiences, such as being rocked or fed. Insomnia related to inadequate limit-setting is a disorder most common in children who are preschool-aged and older and is characterized by active resistance, verbal protests, and repeated demands at bedtime. Guidance to parents about healthy sleep practices helps to prevent sleep problems and is also an important first step in treatment. An integral part of the bedtime routine is the institution of a bedtime and sleep schedule that ensures a developmentally appropriate amount of sleep. A consistent nightly bedtime will help to set the circadian clock and enable the child to fall asleep more easily. Treatment of primary insomnia in older children and adolescents usually involves behavioral interventions that resemble those used in adults. Establishing a consistent sleep schedule is also important for older children and adolescents for whom poor sleep hygiene is a common cause of sleep problems. Pharmacologic therapy for the treatment of childhood insomnia is not a first-line treatment and should always be combined with behavioral therapy.

Optimization of light exposure and sleep schedule for circadian rhythm entrainment

The circadian rhythm, called Process C, regulates a wide range of biological processes in humans including sleep, metabolism, body temperature, and hormone secretion. Light is the dominant synchronizer of the circadian rhythm—it has been used to regulate the circadian phase to cope with jet-lag, shift work, and sleep disorder. The homeostatic oscillation of the sleep drive is called Process S. Process C and Process S together determine the sleep-wake cycle in what is known as the two-process model. This paper addresses the regulation of both Process C and Process S by scheduling light exposure and sleep based on numerical simulations of circadian rhythm and sleep mathematical models. This is a significant step beyond the existing literature that only considers the entrainment of Process C. Regulation of the two-process model poses several unique features and challenges: 1. Process S is non-smooth, i.e., the homeostatic dynamics are different in the sleep and wake regimes; 2. Light only indirectly affects Process S through Process C; 3. Light does not affect Process C during sleep. We consider two scenarios: optimizing light intensity as the control input with spontaneous (i.e., unscheduled) sleep/wake times and jointly optimizing the light intensity and the sleep/wake times, which allows limited delayed sleep and early waking as part of the decision variables. We solve the time-optimal entrainment problem for the two-process model for both scenarios using an extension of the gradient descent algorithm to non-smooth systems. To illustrate the efficacy of our time-optimal entrainment strategies, we consider two common use cases: transmeridian travelers and shift workers. For transmeridian travelers, joint optimization of the two-process model avoids the unrealistic long wake duration when only Process C is considered. The entrainment time also decreases when both the light input and the sleep schedule are optimized compared to when only the light input is optimized. For shift workers, we show that the entrainment time is significantly shortened by optimizing the night shift working light.

Confinement, partial sleep deprivation and defined physical activity–influence on cardiorespiratory regulation and capacity

Introduction Adequate cardiorespiratory fitness is of utmost importance during spaceflight and should be assessable via moderate work rate intensities, e.g., using kinetics parameters. The combination of restricted sleep, and defined physical exercise during a 45-day simulated space mission is expected to slow heart rate (HR) kinetics without changes in oxygen uptake ($${\dot{\text{V}}\text{O}}_{{2}}$$ V ˙ O 2 ) kinetics. Methods Overall, 14 crew members (9 males, 5 females, 37 ± 7 yrs, 23.4 ± 3.5 kg m−2) simulated a 45-d-mission to an asteroid. During the mission, the sleep schedule included 5 nights of 5 h and 2 nights of 8 h sleep. The crew members were tested on a cycle ergometer, using pseudo-random binary sequences, changing between 30 and 80 W on day 8 before (MD-8), day 22 (MD22) and 42 (MD42) after the beginning and day 4 (MD + 4) following the end of the mission. Kinetics information was assessed using the maxima of cross-correlation functions (CCFmax). Higher CCFmax indicates faster responses. Results CCFmax(HR) was significantly (p = 0.008) slower at MD-8 (0.30 ± 0.06) compared with MD22 (0.36 ± 0.06), MD42 (0.38 ± 0.06) and MD + 4 (0.35 ± 0.06). Mean HR values during the different work rate steps were higher at MD-8 and MD + 4 compared to MD22 and MD42 (p < 0.001). Discussion The physical training during the mission accelerated HR kinetics, but had no impact on mean HR values post mission. Thus, HR kinetics seem to be sensitive to changes in cardiorespiratory fitness and may be a valuable parameter to monitor fitness. Kinetics and capacities adapt independently in response to confinement in combination with defined physical activity and sleep.

Role of Nutritive Factors in Infants Sleep Management

The organized infant’s sleep schedule is the crucial part of normal individual development. On the contrary, restless sleep, nocturnal awakening, long wakefulness can lead to deviations in physical, psychomotor, and cognitive development. Feeding schedule organized according to the time of a day and circadian rhythms (chrono-nutrition concept) can be useful for prevention and correction of such disorders. You are aware of the effect of such factors as feeding before night's sleep, nutrition at dark time of a day, diet enriched with triptophane and nucleotides, on the maturation and consolidation of infants sleep. The correlation between intestinal microbiota and factors affecting the circadian and metabolic activity of the body are presented: day-night cycles, sleep and wake, diet and nutrition. Targeted regulation of the intestinal microbiota through products enriched with functional components (prebiotics) can lead to the development of healthy sleep in infants via axis “brain – intestine – microbiota”.

220 Sleep schedule changes during the COVID-19 pandemic: Relations to circadian preferences

Introduction The COVID-19 pandemic profoundly altered individual lifestyles, reducing commutes and restricting nocturnal in-person socialization. We examine whether the stay-at-home orders and the attendant increase in sleep scheduling autonomy, impact bedtimes and waketimes and influence circadian preference alignment. Methods We compared bedtimes and wake times during the 4 weeks before and after a March 19th, 2020 stay-at-home order announcement. Data from the PSG-validated SleepScore Mobile Application were analyzed. Users answering a circadian preference question (a five-point Likert scale ranging from “definitely a morning person” to “definitely an evening person”) who also recorded 10 or more nights of sleep both before and after the March 19th announcement were included in the analysis. The data set included 69,656 total nights of sleep from 1,487 users: 51.0% female, age range 18 to 91 years (mean = 50.3 +/- 30.3). Differences in average bedtime and wake time before and after March 19th were compared using paired sample t-tests. Associations between circadian preference and changes in bedtime and wake time were examined using Spearman’s correlation coefficient. Results All five circadian preference groups showed a significant delay in both bedtime and wake time (p &lt; .01) after the March 19th announcement. Greatest delays were observed in those reporting the strongest eveningness preference, with median bedtimes being 17 minutes later and wake times 33 minutes later. Delays were smallest in users with the strongest morningness preference, with bedtimes being 7 minutes later and wake times 12 minutes later. Wake time delay was significantly greater than bedtime delay for evening types (p &lt; 0.001) but not morning types. Eveningness preference was associated with greater bedtime delay (Spearman correlation = 0.098, p &lt;0.001) and wake time delay (Spearman correlation= 0.178, p &lt; 0.000001). Conclusion The stay-at-home order provided many individuals more freedom to choose their sleep schedule. This increased sleep scheduling autonomy was associated with delayed bedtimes and wake times for each circadian preference group, with the evening-types exhibiting the greatest shift towards a later sleep schedule. We conclude that stay-at-home orders allowed evening types to choose sleep schedules more aligned with their natural tendencies. Support (if any):

240 Habitual Sleep Changes Following COVID-19 Outbreak

Introduction The ongoing COVID-19 pandemic emerges as one of the most impressive and strenuous events of the century, with unthinkably huge global effects. We aimed at analyzing if and how does the pandemic affect sleep and related behaviors. Methods We reviewed 48,047 nights recorded in the US with the Sleeprate application by 3,381 users during a period of 2 years, December 2018-November 2020. Nightly data included perceived and measured sleep parameters. In addition, users reported their perceived daytime stress and sleepiness. We analyzed the monthly variability of the studied parameters and compared their values during the COVID-19 period of March-November 2020 (CP) with those in the previous corresponding period in 2019, the pre-COVID-19 period (PCP). Results Starting March 2020, wake-up time (WUT) was significantly delayed relative to PCP. WUT in April 2020 was the latest (8:06AM±2:12hours, mean±SD, p&lt;.000), being an hour later than in April 2019. This delay started to diminish in June 2020, reaching 7:27AM±2:10 hours by November 2020, which was not significantly higher than during PCP. Bedtime (BT) exhibited similar behavior, yet it returned to PCP times faster. Delayed BT and WUT on weekends were observed during CP as well as PCP. No consistent differences in sleep duration or sleep efficiency were detected between CP and PCP. Subjective sleep satisfaction was higher in CP relative to PCP. However, daytime sleepiness and daytime stress were also higher during most of CP compared to PCP. Conclusion Our data, based on digital in-app sleep diaries coupled with perceived sleep parameters, demonstrate the pandemic’s effects on sleep behavior in the US. Users in this study adapted to the new circumstances with delayed sleep schedule, while not reducing the sleep opportunity. The higher sleep satisfaction may be connected to later sleep schedules, allowing a wake-up time that fits better human biological clocks. The reported increased stress and sleepiness further portray the uncertainty and turbulence characterizing the pandemic’s effects on populations life during the pandemic. As good sleep is linked with immune response efficacy, higher quality of life, and improved mood, the importance of sleep must not be overlooked, especially during the pandemic. Support (if any):