Pubertal changes in daytime sleepiness

Digital media use and its effects on digital eye strain and sleep quality in adolescents: A new emerging epidemic?

This study examines the association between excessive digital media use and adverse health outcomes, specifically Digital Eye Strain (DES) and Poor Sleep Quality (PSQ), in adolescents. A cross-sectional survey of 512 participants (aged 11-18 years) assessed DES and PSQ using the Computer Vision Syndrome Questionnaire and the Pittsburgh Sleep Quality Index. We found a high prevalence of DES (63.7%) and PSQ (51.2%). Factors associated with DES included using digital media for more than two hours daily, increased post-pandemic digital consumption, shorter breaks, and PSQ. Extended daily digital media use (>4 hours), bedtime usage, older age, female sex, online education and DES were significantly associated with PSQ. These findings highlight the harmful effects of excessive digital media use on adolescent health, especially post-COVID-19. The intricate link between DES and PSQ underscores the need for public health interventions to promote healthy digital habits.

Re-Evaluating Recommended Optimal Sleep Duration: A Perspective on Sleep Literacy

A significant number of adolescents experience sleepiness, primarily due to sleep deprivation. The detrimental effects of inadequate sleep on both physical and mental health are well documented, particularly during adolescence-a critical developmental stage that has far-reaching implications for later life outcomes. The International Classification of Diseases 11th Revision recently introduced the disorder termed 'insufficient sleep syndrome,' characterized by a persistent reduction in sleep quantity. However, diagnosing this condition based solely on sleep duration is challenging due to significant individual variation in what constitutes optimal sleep. Despite this, managing sleep debt remains difficult without a clear understanding of individual optimal sleep needs. This review aims to reassess recommended sleep durations, with a focus on enhancing sleep literacy. Beginning with an exploration of insufficient sleep syndrome, this review delves into research on optimal sleep duration and examines foundational studies on sleep debt's impact on the developing brain. Finally, it addresses the challenges inherent in sleep education programs from the perspective of sleep literacy. By doing so, this review seeks to contribute to a deeper understanding of the chronic sleep debt issues faced by adolescents, particularly those affected by insufficient sleep syndrome.

Recommended protocols for the Multiple Sleep Latency Test and Maintenance of Wakefulness Test in children: guidance from the American Academy of Sleep Medicine

The American Academy of Sleep Medicine commissioned a task force of clinical experts in pediatric sleep medicine to review published literature on performing the Multiple Sleep Latency Test (MSLT) and Maintenance of Wakefulness Test for diagnosis and management of central disorders of hypersomnolence among children and adolescents. This paper follows a format similar to that of the paper "Recommended protocols for the Multiple Sleep Latency Test and Maintenance of Wakefulness Test in adults: guidance from the American Academy of Sleep Medicine" that was published in 2021. Since there is insufficient evidence to specify a recommended protocol for the Maintenance of Wakefulness Test in children and adolescents, this paper focuses only on the MSLT protocol. This protocol paper provides guidance to health care providers who order, sleep specialists who interpret, and technical staff who administer the MSLT to pediatric patients. Similar to the adult protocol paper, this document provides guidance based on pediatric expert consensus and evidence-based data when available. Topics include patient preparation, evaluation of medication and substance use, sleep needs before testing, scheduling considerations, optimal test conditions for youth, and documentation. Specific changes recommended for pediatric MSLT protocols include (1) provision of a minimum of 7 hours of sleep (with a minimum 8-hour recording time) on polysomnography the night before the MSLT, ideally meeting age-based needs; (2) use of clinical judgment to guide the need for sleep-disordered breathing treatments before polysomnography-MSLT testing; and (3) shared patient-health care provider decision-making regarding modifications in the protocol for children and adolescents with neurodevelopmental/neurological disorders, young age, and/or delayed sleep phase.

CITATION

Maski KP, Amos LB, Carter JC, Koch EE, Kazmi U, Rosen CL. Recommended protocols for the Multiple Sleep Latency Test and Maintenance of Wakefulness Test in children: guidance from the American Academy of Sleep Medicine. J Clin Sleep Med. 2024;20(4):631-641.

Is there a role for repeating the multiple sleep latency test across childhood when initially non-diagnostic?

BACKGROUND

The gold standard investigation for central disorders of hypersomnolence is the Multiple Sleep Latency Test (MSLT). As the clinical features of these disorders of hypersomnolence evolve with time in children, clinicians may consider repeating a previously non-diagnostic MSLT. Currently there are no guidelines available regards the utility and timing of repeating paediatric MSLTs.

METHODS

Retrospective review of children aged 3-18years with ≥2MSLTs between 2005 and 2022. Narcolepsy was defined as mean sleep latency (MSL) <8min with ≥2 sleep onset REM (SOREM); idiopathic hypersomnia (IH) was defined as MSL <8min with <2 SOREM. MSLTs not meeting these criteria were labelled non-diagnostic.

RESULTS

19 children (9 female) with initial non-diagnostic MSLT underwent repeat MSLT, with 6 proceeding to a 3rd MSLT following 2 non-diagnostic MSLTs. The 2nd MSLT resulted in diagnosis in 6/19 (32 %) (3 narcolepsy, 3 IH); and 2/6 (33 %) 3rd MSLT were diagnostic (2 IH). Median age at initial MSLT was 7.5y (range 3.4-17.8y), with repeat performed after median of 2.9y (range 0.9-8.2y), and 3rd after a further 1.9 years (range 1.2-4.2y). Mean change in MSL on repeat testing was -2min (range -15.5min to +4.9min, p = 0.18). Of the 8 diagnostic repeat MSLTs, in addition to the MSL falling below 8 min, 2 children also developed ≥2 SOREM that had not been previously present.

CONCLUSIONS

A third of repeat MSLTs became diagnostic, suggesting repeat MSLT should be considered in childhood if clinical suspicion persists. Further work needs to address the ideal interval between MSLTs and diagnostic cut-points specific to the paediatric population.

Normal Sleep in Children and Adolescence

Adequate sleep is essential for healthy development in childhood and adolescence. Healthy sleep contributes to good physical health, immune function, mental health, and academic performance. The regulation and architecture of sleep change greatly across childhood and adolescence, and the ability to obtain sufficient sleep is impacted by a range of factors that change with maturation. This article describes normal sleep across childhood and adolescence and discusses some of the most common barriers to adequate sleep, including early school start times, technology use, and changes to circadian rhythms, and sleep homeostasis across puberty.

Maturational trend of daytime sleep propensity in adolescents

STUDY OBJECTIVES

The teenage increase in sleepiness is not simply a response to decreasing nighttime sleep duration. Daytime sleepiness increases across adolescence even when prior sleep duration is held constant. Here we determine the maturational trend in daytime sleep propensity assessed with the multiple sleep latency test (MSLT) and assess the trend's relation to pubertal maturation and changes in the sleep electroencephalogram. We also evaluate whether the relation of daytime sleep propensity to prior sleep duration changes between ages 10 and 23 years.

METHODS

Participants (n = 159) entered the study between ages 9.8 and 22.8 years and were studied annually for up to 3 years. Annually, participants kept each of three sleep schedules in their homes: 7, 8.5, and 10 hours in bed for 4 consecutive nights with polysomnography on nights 2 and 4. MSLT-measured daytime sleep propensity was assessed in the laboratory on the day following the fourth night.

RESULTS

A two-part linear spline model described the maturation of daytime sleep propensity. MSLT sleep likelihood increased steeply until age 14.3 years, after which it did not change significantly. The maturational trend was strongly associated with the adolescent decline in slow-wave (delta, 1-4 Hz) EEG power during NREM sleep and with pubertal maturation assessed with Tanner stage measurement of breast/genital development. The effect of prior sleep duration on sleep likelihood decreased with age.

CONCLUSIONS

Adolescent brain changes related to pubertal maturation and those reflected in the delta decline contribute to the adolescent increase in daytime sleep propensity.

Sleep, Nutrition, and Injury Risk in Adolescent Athletes: A Narrative Review

This narrative review explores the impact of sleep and nutrition on injury risk in adolescent athletes. Sleep is viewed as essential to the recuperation process and is distinguished as an active participant in recovery through its involvement in growth, repair, regeneration, and immunity. Furthermore, the literature has shown that the sleep of athletes impacts elements of athletic performance including both physical and cognitive performance, recovery, injury risk, and mental well-being. For sleep to have a restorative effect on the body, it must meet an individual's sleep needs whilst also lasting for an adequate duration and being of adequate quality, which is age-dependent. The literature has suggested that athletes have increased sleep needs compared to those of the general population and thus the standard recommendations may not be sufficient for athletic populations. Therefore, a more individualised approach accounting for overall sleep health may be more appropriate for addressing sleep needs in individuals including athletes. The literature has demonstrated that adolescent athletes achieve, on average, ~6.3 h of sleep, demonstrating a discrepancy between sleep recommendations (8-10 h) and actual sleep achieved. Sleep-wake cycles undergo development during adolescence whereby adaptation occurs in sleep regulation during this phase. These adaptations increase sleep pressure tolerance and are driven by the maturation of physiological, psychological, and cognitive functioning along with delays in circadian rhythmicity, thus creating an environment for inadequate sleep during adolescence. As such, the adolescent period is a phase of rapid growth and maturation that presents multiple challenges to both sleep and nutrition; consequently, this places a significant burden on an adolescent athletes' ability to recover, thus increasing the likelihood of injury. Therefore, this article aims to provide a comprehensive review of the available literature on the importance of sleep and nutrition interactions in injury risk in adolescent athletes. Furthermore, it provides foundations for informing further investigations exploring the relation of sleep and nutrition interactions to recovery during adolescence.

Sleep quality and its relationship with school schedules and mental health of Nigerian secondary school adolescents

STUDY OBJECTIVES

This study aimed to determine the sleep quality of in-school Nigerian adolescents and its association with their schooling and mental health outcomes.

METHODS

The study was a descriptive cross-sectional study. It was conducted among adolescents attending public and private secondary schools within the Ife Central Local Government, Osun State, southwestern Nigeria. A multistage sampling technique was used to select study participants. The Pittsburgh Sleep Quality Index, 9-item Patient Health Questionnaire (PHQ-9), and 7-item General Anxiety Disorder questionnaires were used to determine sleep quality, depression, and anxiety, respectively.

RESULTS

We studied 448 adolescents aged between 10 and 19 years with a mean age of 15.0 ± 1.8 years. The majority of our respondents (85.0%) had poor sleep quality. More than half of the respondents (55.1%) had insufficient sleep during weekdays, while only 34.8% had insufficient sleep during weekends. The school closing time and school type showed a statistically significant association with sleep quality (P = .039 and .005, respectively). The odds of having poor sleep quality increased by 2-fold among adolescents in private schools when compared with those in public schools (adjusted odds ratio = 1.97, 95% confidence interval = 1.069-3.627). Using multiple linear regression, only depression showed a statistically significant association with sleep quality at 95% confidence interval (CI = 0.073 to 0.219, P < .001), such that for every unit change in depression scores (PHQ-9), there will be a corresponding increase of 0.103 in sleep quality.

CONCLUSIONS

Sleep quality is poor in adolescents and adversely associated with their mental health. This should also be addressed in the development of appropriate interventions.

CITATION

Olorunmoteni OE, Fehintola FO, Seun-Fadipe C, Komolafe MA, Mosaku KS. Sleep quality and its relationship with school schedules and mental health of Nigerian secondary school adolescents. J Clin Sleep Med. 2023;19(11):1895-1904.

The effect of watching OTT late at night on the sleep pattern of users

This study aimed to answer the question of how media users will reallocate their sleep time when their main content channel changes from real-time broadcasting to selective viewing through the over-the-top (OTT) media streaming service. To draw a causal inference between OTT consumption and sleep patterns, the difference-in-difference (DID) estimation method was applied. With the DID approach, a clear distinction between treatment and control groups is essential because the main treatment effects can be screened by the compounding effects. While the conventional way of dividing two groups relies on the selection of limited variables, this study adopted random forest nearest-neighbor propensity score matching based on a machine learning algorithm to divide the two groups. This allows for meticulous matching of the two groups except for treatment. Results show that watching OTT late at night has a significant effect on reducing the total sleep duration on average by about 18-20 min (maximum about 30 min at 95% confidence level) and delaying bedtime by about 18 min (maximum about 26 min at 95% confidence level). This study showed that the selective viewing of content through OTT has the advantage of widening the range of content choices for media users and helping in arranging their time more autonomously, but watching content through OTT late at night leads to media users' departure from the existing sleep routine.

Development of evening sleep homeostatic pressure in early adolescent boys

The physiological processes governing sleep regulation show maturational changes during adolescent development. To date, data are available to specify when delays in circadian timing occur; however, no longitudinal data exist to characterize the maturation of the accumulation of sleep pressure across the evening. The aim of this longitudinal study was to test whether this change in evening sleep propensity can be identified during early adolescence. Twenty pre-pubescent boys' (Mage = 10.3, SD = 0.4 years) evening sleep homeostats were assessed using a series of sleep latency tests every hour (7:30 p.m. to 3:30 a.m.) at 6-month intervals across four waves. While results revealed shorter sleep onset latencies with increasing wakefulness (p < .001), this effect was not moderated by study wave (p = .79). Evening sleep propensity thus appears to remain stable in boys during early adolescence. Future studies should expand upon these findings by using larger samples of girls as well as boys across an extended age range during the teenage years.

Effects of emerging alcohol use on developmental trajectories of functional sleep measures in adolescents

STUDY OBJECTIVES

Adolescence is characterized by significant brain development, accompanied by changes in sleep timing and architecture. It also is a period of profound psychosocial changes, including the initiation of alcohol use; however, it is unknown how alcohol use affects sleep architecture in the context of adolescent development. We tracked developmental changes in polysomnographic (PSG) and electroencephalographic (EEG) sleep measures and their relationship with emergent alcohol use in adolescents considering confounding effects (e.g. cannabis use).

METHODS

Adolescents (n = 94, 43% female, age: 12-21 years) in the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) study had annual laboratory PSG recordings across 4-years. Participants were no/low drinkers at baseline.

RESULTS

Linear mixed effect models showed developmental changes in sleep macrostructure and EEG, including a decrease in slow wave sleep and slow wave (delta) EEG activity with advancing age. Emergent moderate/heavy alcohol use across three follow-up years was associated with a decline in percentage rapid eye movement (REM) sleep over time, a longer sleep onset latency (SOL) and shorter total sleep time (TST) in older adolescents, and lower non-REM delta and theta power in males.

CONCLUSIONS

These longitudinal data show substantial developmental changes in sleep architecture. Emergent alcohol use during this period was associated with altered sleep continuity, architecture, and EEG measures, with some effects dependent on age and sex. These effects, in part, could be attributed to the effects of alcohol on underlying brain maturation processes involved in sleep-wake regulation.

Integrating sleep health into resilience research

Sleep is a biological necessity that is a critical determinant of mental and physical well-being. Sleep may promote resilience by enhancing an individual's biological preparedness to resist, adapt and recover from a challenge or stressor. This report analyzes currently active National Institutes of Health (NIH) grants focussed on sleep and resilience, specifically examining the design of studies that explore sleep as a factor that promotes health maintenance, survivorship, or protective/preventive pathways. A search of NIH R01 and R21 research project grants that received funding in Fiscal Years (FY) 2016-2021 and focussed on sleep and resilience was conducted. A total of 16 active grants from six NIH institutes met the inclusion criteria. Most grants were funded in FY 2021 (68.8%), used the R01 mechanism (81.3%), were observational studies (75.0%), and measured resilience in the context of resisting a stressor/challenge (56.3%). Early adulthood and midlife were most commonly studied and over half of the grants focussed on underserved/underrepresented populations. NIH-funded studies focussed on sleep and resilience, or the ways in which sleep can influence an individual's ability to resist, adapt, or recover from a challenging event. This analysis highlights an important gap and the need to expand research focussed on sleep as a promotor of molecular, physiological, and psychological resilience.

The effect of brain-derived neurotrophic factor Val66Met polymorphism on adolescent activity and rest rhythms, circadian preferences and attentional performance

BACKGROUND

Variations in circadian regulating mechanisms generate different individual preferences in respect of sleep and activity timing, which are known as chronotypes. In this sense, specifically during adolescence, there is a greater tendency for an eveningness chronotype. One factor that has been shown to have an impact on circadian rhythm patterns, as well as on some aspects of cognitive function, is the relatively common Val66Met (rs6265) polymorphism in the human brain-derived neurotrophic factor gene.

OBJECTIVE

This study aimed to evaluate the effect of the BDNF Val66Met polymorphism on the performance of adolescents in attentional tests, circadian preferences and activity-rest rhythm.

METHODS

85 healthy high school students completed the Morningness-Eveningness Questionnaire to assess their circadian preferences; were evaluated using the Psychological Battery for Attention Assessment; and were categorized as carriers and non-carriers of the rs6265 polymorphism using the TaqMan rt-PCR technique. A subsample of 42 students had their activity/rest rhythm recorded by actigraphy for nine days from which sleep parameters were estimated.

RESULTS

Circadian preference did not affect attentional performance (p > 0.1), but the time that the students attended school had an impact on all types of attention with morning shift students scoring higher, regardless of chronotype (p < 0.05). The presence of the BDNF Val66Met polymorphism was associated only with alternate attention performance (p < 0.05). Regarding actigraphy evaluation, the carriers of the polymorphism demonstrated significantly higher total time in bed, total sleep time, social jetlag, and earlier sleep onset.

CONCLUSIONS

The results indicate some degree of adaptation in the students' attentional performance, according to their school schedules. The presence of BDNF polymorphism demonstrated a counterintuitive impact on attentional performance, comparing to previous findings. The findings reinforce the effect of genetic traits on sleep-wake rhythm parameters, when objectively evaluated.

Attachment to Mother and Father, Sleep, and Well-Being in Late Middle Childhood

The security of attachment has been related to several advantageous developmental outcomes, such as good sleep quality and higher well-being indicators. However, few studies concern the associations between attachment dimensions to both parents, sleep, and well-being in late middle childhood. Our study aims to expand knowledge in this area, clarifying the above-mentioned associations by considering the secure base and safe haven dimensions of attachment. We also investigate the role of sleep as a mediator of the relationship between attachment and well-being. The 258 participants (49.2% girls, mean age = 11.19, SD = 0.85) completed self-report questionnaires regarding attachment (KSS), sleep (SSR), and well-being (CHIP-CE). The results show significant associations between attachment to both parents (0.40 ** ≤ r ≤ 0.61 **) and between attachment security, sleep (-0.21 ** ≤ r ≤ -0.35 **) and child well-being (0.42 ** ≤ r ≤ 0.47 **). Besides, sleep quality partially mediated the relations between all attachment dimensions to both parents and well-being. The results are discussed in light of attachment theory, focusing on the comparison between attachment to mother and father as a valid framework to unravel differences in child well-being, with sleep as a process that can help to explain the mechanisms through which attachment security enables subjective perceptions of well-being.

Sleep deprivation among adolescents in urban and indigenous-rural Mexican communities

Comparing the nature of adolescent sleep across urban and more isolated, rural settings through an ecological, cross-cultural perspective represents one way to inform sleep nuances and broaden our understanding of human development, wellbeing and evolution. Here we tested the Social Jetlag Hypothesis, according to which contemporary, urban lifestyles and technological advances are associated with sleep insufficiency in adolescents. We documented the adolescent sleep duration (11-16 years old; X̅ = 13.7 ± 1.21; n = 145) in two small agricultural, indigenous and one densely urban context in Mexico to investigate whether adolescents in socio-ecologically distinct locations experience sleep deprivation. Sleep data was assembled with actigraphy, sleep diaries and standardized questionnaires. We employed multilevel models to analyze how distinct biological and socio-cultural factors (i.e., pubertal maturation, chronotype, napping, gender, working/schooling, access to screen-based devices, exposure to light, and social sleep practices) shape adolescent sleep duration. Results suggest that the prevalence of adolescent short sleep quotas is similar in rural, more traditional environments compared to highly urbanized societies, and highlight the influence of social activities on the expression of human sleep. This study challenges current assumptions about natural sleep and how adolescents slept before contemporary technological changes occurred.

Adolescent sleep myths: Identifying false beliefs that impact adolescent sleep and well-being

OBJECTIVE

Commonly held beliefs about sleep unsupported by scientific evidence (ie, myths) among adolescents and their parents/caregivers may adversely influence sleep-related attitudes and behaviors among adolescents. Thus, identifying such myths with the goal of developing effective evidence-based counter-messages has the potential to improve sleep health in adolescents.

METHOD

We identified myths with a panel of adolescent sleep health experts (n = 12) using the Delphi method in three sequential steps: (1) focus groups; (2) online discussion; and (3) closed-ended questionnaires with which the experts rated myths on: (1) falseness and (2) public health significance using 5-point Likert scales ranging from 1 (not at all false/important for public health) to 5 (extremely false/important for public health). Next, we explored the prevalence of the myths among a demographically diverse sample of parents/caregivers of adolescents in the United States. Finally, we report the counterevidence to refute each myth.

RESULTS

Ten myths about adolescent sleep were identified by the experts using the Delphi method. The most prevalent myths were the beliefs that (1) "Going to bed and waking up late on the weekends is no big deal for adolescents, as long as they get enough sleep during that time," reported by 74% of parents/caregivers; (2) "If school starts later, adolescents will stay up that much later," reported by 69% of parents/caregivers; and (3) "Melatonin supplements are safe for adolescents because they are natural," reported by 66% of parents/caregivers.

CONCLUSION

Parents/caregivers have the potential to serve as sleep health advocates for their adolescent and support their adolescent's sleep health behaviors. Our study found that many parents/caregivers endorse myths about adolescent sleep that may hinder their ability to support their adolescent's sleep health. Future research may explore methods for promoting evidence-based beliefs about adolescent sleep among parents/caregivers.

Do both timing and duration of screen use affect sleep patterns in adolescents?

BACKGROUND

Sleep duration has declined in adolescents over the last 30 years and screen use has been identified as a risk factor. Studies have examined the duration of screen use and screen-based activities but have not differentiated between evening and night-time use.

METHODS

Cross sectional questionnaire survey of adolescents recruited in schools. Sleep habits on school nights and weekends, symptoms of insomnia and daytime repercussions were recorded using an online questionnaire administered in the classroom setting. Sleep deprivation (<7 hours in bed /night), school night sleep restriction (≥2 hours difference in sleep duration on school nights vs weekends), excessive sleepiness (score >6 on a visual analogue scale), duration of screen use and timing of screen use (evening vs after bedtime) were determined.

RESULTS

2513 students (53.4% female, median age 15 years) were included. 20% were sleep deprived and 41% sleep restricted. A clear dose effect relationship in a model controlling for age, sex, school level and sociodemographic class was seen with all levels of night-time screen use on sleep deprivation and sleep restriction (>2 hours use sleep deprivation OR 5.23[3.03-9.00]. sleep restriction OR 2.05[1.23-3.42]) and > 2 hours evening use (>2 hours use sleep deprivation OR 2.72[2.15-3.44] sleep restriction OR 1.69[1.36-2.11]) but not moderate evening use. All night-time use and > 2 hours evening use increased the risk of insomnia, non refreshing sleep, and affected daytime function (daytime sleepiness, lack of energy and irritability).

CONCLUSIONS

Both duration of screen use and timing are associated with adverse effects on sleep and daytime functioning in adolescents. More than 2 hours evening use and all night-time use should be avoided.

Characteristic Sleep Patterns and Associated Obesity in Adolescents

Poor sleep adversely affects health and may cause obesity. Poor sleep includes short sleep duration, low quality of sleep, and sleep discrepancy. Although most studies have focused on the association between sleep duration and obesity, poor sleep is a significant risk factor for obesity. Adolescents have characteristic sleep patterns which correspond to poor sleep. Adolescents sleep late due to various biological and psychosocial factors; also, they wake up early to be on time for school. This causes them to sleep less. To make up for this sleep debt, adolescents sleep more on non-school days, which causes sleep discrepancies. Therefore, since adolescents have characteristic sleep patterns, an in-depth investigation is needed to identify whether poor sleep is a risk for obesity. This article presents an overview of the characteristic sleep patterns of adolescents, and reviews studies on the association of each sleep pattern with obesity.

Effect of nanovesicular surface-functionalization via chitosan and/or PEGylation on cytotoxicity of tamoxifen in induced-breast cancer model

AIMS

The effect of surface-modification of Tamoxifen (Tam)-loaded-niosomes on drug cytotoxicity and bio-distribution, via functionalization with chitosan and/or PEGylation, was investigated.

MATERIALS AND METHODS

Tam-loaded hybrid-nanocarriers (Tam-loaded niosomes, chitosomes, PEGylated niosomes, and PEGylated chitosomes) were formulated and characterized.

KEY FINDINGS

Chitosanization with/without PEGylation proved to selectively enhance Tam-release at the cancerous-acidic micromilieu. Cytotoxic activity study showed that Tam-loaded PEGylated niosomes had a lower IC₅₀ value on MCF-7 cell line (0.39, 0.35, and 0.27 times) than Tam-loaded PEGylated chitosomes, Tam-loaded niosomes, and Tam-loaded chitosomes, respectively. Cell cycle analysis showed that PEGylation and/or Chitosanization significantly impact Tam efficiency in inducing apoptosis, with a preferential influence of PEGylation over chitosanization. The assay of Annexin-V/PI double staining revealed that chitosanized-nanocarriers had a significant role in increasing the incidence of apoptosis over necrosis. Besides, PEGylated-nanocarriers increased apoptosis, as well as total death and necrosis percentages more than what was shown from free Tam. Moreover, the average changes in both Bax/Bcl-2 ratio and Caspase 9 were best improved in cells treated by Tam-loaded PEGylated niosomes over all other formulations. The in-vivo study involving DMBA-induced-breast cancer rats revealed that PEGylation made the highest tumor-growth inhibition (84.9 %) and breast tumor selectivity, while chitosanization had a lower accumulation tendency in the blood (62.3 ng/ml) and liver tissues (103.67 ng/ml). The histopathological specimens from the group treated with Tam-loaded PEGylated niosomes showed the best improvement over other formulations.

SIGNIFICANCE

All these results concluded the crucial effect of both PEGylation and chitosan-functionalization of Tam-loaded niosomes in enhancing effectiveness, targetability, and safety.

Changes in Sleep Patterns in Korean Early Adolescents during Sexual Maturation

Purpose: Teenagers’ sleep patterns show physiological delays influenced by sexual maturation and other external time-related factors. However, Korean adolescents show differences in the onset of pubertal development and have shorter sleep durations than other adolescents worldwide. Therefore, we assessed sleep patterns and sexual maturation in Korean early adolescents to evaluate changes in sleep patterns in relation to sexual maturation in early adolescents with sleep deprivation.Methods: From March to August 2017, we surveyed children aged 10 to 12 years in Seongnam (Seongnam Atopy Project). We evaluated items related to sleep and sexual maturation, assessed sleep duration and sleepiness scale scores, and analyzed the relationships of sleep parameters with sex, height, weight, and sexual maturation rating (SMR).Results: In total, 620 children were included. Sleep duration was 8.63±0.81 hours in boys and 8.40±0.98 hours in girls. Sleep started from PM 11:00±AM 0:47 in boys and PM 11:13±AM 1:06 in girls, and ended at AM 7:38±AM 0:27 in boys and AM 7:34±AM 0:27 in girls. After adjusting for sex and standardized body mass index, bedtime was delayed as the SMR increased (mean delay for each rating increase, 0.251 hours; P=0.001; 95% confidence interval [CI], 0.105 to 0.397). SMR did not influence the wake-up time, although sleep duration decreased as the SMR increased (mean decrease for each rating increase, 0.258 hours; P=0.001; 95% CI, –0.403 to –0.114). The sleepiness scale scores showed no relationship with SMR. Conclusion: Sleep patterns, especially sleep duration and bedtimes, show changes with sexual maturation in adolescents, who are vulnerable to sleep deprivation.

Association of Electronic Media Use and Sleep Habits Among Secondary School Students in Al-Madinah

Objectives: To ascertain the relationship between electronic media use and sleep patterns among secondary school students in Al-Madinah, Saudi Arabia.

Methods: This was a descriptive cross-sectional study, conducted from July 2021 to December 2021. This study examined eight female secondary high schools, in Al-Madinah, Saudi Arabia. The sampling technique used was the stratification of governmental schools according to their location in the north, south, east, and west. According to the WHO sample size calculator, the sample size was 375. The Statistical Package for the Social Sciences version 26 (SPSS version 26) (SPSS Incl., Chicago, IL) was used for the analysis of data.

Results: A total of 388 female students were recruited, from the age group 12 to 40 years, with a mean age group of 16.45 ± 4.25 years. The majority of participants in our research utilized various types of electronic devices before going to bed. Some 335 individuals reported using electronic devices on a daily basis while at school, while 357 reported using electronic devices prior to sleeping on weekends. The more time spent on electronic gadgets, the more sleep is interrupted (p-value = 0.005). This condition was more prevalent among older children: 55% of third-year children and 41% of second-year children reported having it (p = 0.01). More than 20% had difficulty sleeping. Around 5% of respondents reported experiencing frequent nightly awakenings, whereas 23% reported feeling drowsy/sleepy feeling at school. After 10:00 p.m., 43% of the population (mostly the young) headed to bed, while older children remained awake (p = 0.001). Having a mobile phone (odds ratio, OR = 2.5; p = 0.01) or tablet (OR = 2.5; p = 0.05) was a significant predictor of sleep issues in the logistic regression model.

Conclusion: The use of electronic media and the amount of time secondary school children spend on it can significantly alter sleep quality, through interrupted rest, and time, from a reduced duration of sleep. Parents and care providers can help by creating awareness about the negative effects of using electronic media on sleep and health among children.

Chronotype and time of day effects on verbal and facial emotional Stroop task performance in adolescents

This study investigated chronotype and time of day effects on lexical and facial emotion processing tasks and explored relationships with sleep quality and mental health outcomes. Participants were 351 Taiwanese adolescents (204 males) aged 13 to 16 years of age who completed both a Facial-Emotional Stroop and a Lexical-Emotional Stroop task at 08:00-10:00 am or at 14:00-16:00 pm. Chronotype was measured using the Morningness-Eveningness Questionnaire (MEQ) and grouped into Morning (n = 46), Intermediate (n = 248) or Evening types (n = 57). Participants completed validated measures of sleep quality (PSQI) and mental health difficulties (DASS-21). The study observed independent effects of time of day and chronotype on the Facial-Emotional Stroop task. Independent of chronotype group, delayed reaction times to anger stimuli were observed in adolescents tested in the morning. Younger adolescents with an Evening chronotype showed delayed responses to anger faces independent of the time of testing. Facial-Emotional Stroop task performance correlated with reported sleep quality and mental health only in Evening chronotypes, with attenuated responses to anger versus neutral stimuli associated with poorer sleep quality and worse mental health outcomes. An exploratory simple mediation analysis indicated that the relationship between attenuated responses to anger and greater mental health difficulties was fully mediated by poorer sleep quality. This study provides evidence of diurnal and chronotype-related variation in facial threat-related processing in typical adolescent development. It also indicates how social emotional processing is vulnerable to sleep disruptions and is linked to the greater mental health problems observed in adolescents with an eveningness profile.

Adolescent sleep health and school start times: Setting the research agenda for California and beyond: A research summit summary: A research summit summary

In fall 2019, California passed and signed into law SB328, the first US statewide legislation explicitly designed to protect adolescent sleep health by requiring most California public school districts to start no earlier than 8:00 AM for middle schools and 8:30 AM for high schools. Recognizing the unique opportunity presented by the bill's 3-year implementation period, a group of experts in adolescent sleep and school start times held a virtual summit on January 22-23, 2021 to (1) summarize the research on adolescent sleep and school start time change; (2) develop recommendations for relevant, refined, and innovative research areas and research questions; (3) provide input regarding research design, methodology, and implementation; and (4) offer a forum for networking, exchanging ideas, and establishing interdisciplinary research collaborations. Participants represented a multidisciplinary range of academic backgrounds including sleep and circadian biology, neuroscience, education, medicine, public health, mental health, safety, public policy, economics, implementation science, criminology, diversity studies, and science communication. This paper summarizes summit presentations regarding current knowledge on adolescent sleep health and school start times and key research recommendations from small group workshops on topics including research design and tools, methodological issues, sleep health disparities, logistical challenges in conducting school-based research, public-health impact, and novel and expanded approaches to research.

Gender-Based Differences and Associated Factors Surrounding Excessive Smartphone Use Among Adolescents: Cross-sectional Study

BACKGROUND

Excessive smartphone use is a new and debated phenomenon frequently mentioned in the context of behavioral addiction, showing both shared and distinct traits when compared to pathological gaming and gambling.

OBJECTIVE

The aim of this study is to describe excessive smartphone use and associated factors among adolescents, focusing on comparisons between boys and girls.

METHODS

This study was based on data collected through a large-scale public health survey distributed in 2016 to pupils in the 9th grade of primary school and those in the 2nd grade of secondary school. Bayesian binomial regression models, with weakly informative priors, were used to examine whether the frequency of associated factors differed between those who reported excessive smartphone use and those who did not.

RESULTS

The overall response rate was 77% (9143/11,868) among 9th grade pupils and 73.4% (7949/10,832) among 2nd grade pupils, resulting in a total of 17,092 responses. Based on the estimated median absolute percentage differences, along with associated odds ratios, we found that excessive smartphone use was associated with the use of cigarettes, alcohol, and other substances. The reporting of anxiety and worry along with feeling low more than once a week consistently increased the odds of excessive smartphone use among girls, whereas anxiety and worry elevated the odds of excessive smartphone use among boys. The reporting of less than 7 hours of sleep per night was associated with excessive smartphone use in all 4 study groups.

CONCLUSIONS

The results varied across gender and grade in terms of robustness and the size of estimated difference. However, excessive smartphone use was associated with a higher frequency of multiple suspected associated factors, including ever having tried smoking, alcohol, or other substances; poor sleep; and often feeling low and feeling anxious. This study sheds light on some features and distinctions of a potentially problematic behavior among adolescents.

Examining the relationship between poor sleep health and risky driving behaviors among college students

Objective: Risky driving behaviors, such as texting while driving, are common among young adults and increase risk of traffic accidents and injuries. We examine the relationship between poor sleep and risky driving behaviors among college students as potential targets for traffic injury prevention.Methods: Data for this study were obtained from a cross-sectional survey administered to a college student sample in the United States Midwest (n = 1,305). Sleep was measured using the Pittsburgh Sleep Quality Index (PSQI). Risky driving behaviors were measured, including sending texts/emails; reading texts/emails while driving; talking on the phone while driving; falling asleep while driving; and driving under the influence. Risky driving behavior was defined as a response of "just once," "rarely," "sometimes," "fairly often" or "regularly" (reference = "never"). Logistic regression was used to examine the relationship between sleep and risky driving, after adjusting for confounders.Results: Among participants, 75% reported sending texts/emails while driving, 82% reported reading texts/emails while driving, and 84% reported phone talking while driving; 20% reported falling asleep while driving; 8% reported driving under the influence; and 62% reported 3 or more risky behaviors. Compared to those reporting no sleep disturbance, those with sleep disturbance "once or twice a week" were more likely to report sending a text/email while driving (aOR: 2.9, 95%CI:1.7-4.9), reading a text/email while driving (aOR:3.1,95%CI:1.5-5.5), talking on the phone while driving (aOR:1.9, 95%CI:1.0-3.4), and falling asleep while driving (aOR:3.4,95%CI:1.5-7.4). Compared to those reporting no daytime dysfunction, those reporting issues "once or twice a week" were more likely to report talking on the phone while driving (aOR:1.7, 95%CI:1.1-2.7) and falling asleep while driving (aOR:3.6,95%CI:2.3-5.6).Conclusions: Future research may consider designing behavioral interventions that aim to improve sleep, reduce drowsy driving among young adults.

Stability of nocturnal wake and sleep stages defines central nervous system disorders of hypersomnolence

STUDY OBJECTIVES

We determine if young people with narcolepsy type 1 (NT1), narcolepsy type 2 (NT2), and idiopathic hypersomnia (IH) have distinct nocturnal sleep stability phenotypes compared to subjectively sleepy controls.

METHODS

Participants were 5- to 21-year old and drug-naïve or drug free: NT1 (n = 46), NT2 (n = 12), IH (n = 18), and subjectively sleepy controls (n = 48). We compared the following sleep stability measures from polysomnogram recording between each hypersomnolence disorder to subjectively sleepy controls: number of wake and sleep stage bouts, Kaplan-Meier survival curves for wake and sleep stages, and median bout durations.

RESULTS

Compared to the subjectively sleepy control group, NT1 participants had more bouts of wake and all sleep stages (p ≤ .005) except stage N3. NT1 participants had worse survival of nocturnal wake, stage N2, and rapid eye movement (REM) bouts (p < .005). In the first 8 hours of sleep, NT1 participants had longer stage N1 bouts but shorter REM (all ps < .004). IH participants had a similar number of bouts but better survival of stage N2 bouts (p = .001), and shorter stage N3 bouts in the first 8 hours of sleep (p = .003). In contrast, NT2 participants showed better stage N1 bout survival (p = .006) and longer stage N1 bouts (p = .02).

CONCLUSIONS

NT1, NT2, and IH have unique sleep physiology compared to subjectively sleepy controls, with only NT1 demonstrating clear nocturnal wake and sleep instability. Overall, sleep stability measures may aid in diagnoses and management of these central nervous system disorders of hypersomnolence.

Psychometric properties of the Chinese version of the Pittsburgh Sleep Quality Index (PSQI) among Hong Kong Chinese childhood cancer survivors

Background

Sleep disruption is a prevalent symptom reported by survivors of childhood cancer. However, there is no validated instrument for assessing this symptom in this population group. To bridge the literature gap, this study translated and adapted the Pittsburgh Sleep Quality Index (PSQI) for Hong Kong Chinese cancer survivors and examined its psychometric properties and factor structure.

Methods

A convenience sample of 402 Hong Kong Chinese childhood cancer survivors aged 6–18 years were asked to complete the Chinese version of the PSQI, Center for Epidemiologic Studies Depression Scale for Children (CES-DC), Fatigue Scale-Child (FS-C)/Fatigue Scale-Adolescent (FS-A), and Pediatric Quality of Life Inventory (PedsQL). To assess known-group validity, 50 pediatric cancer patients and 50 healthy counterparts were recruited. A sample of 40 children were invited to respond by phone to the PSQI 2 weeks later to assess test–retest reliability. A cutoff score for the translated PSQI used with the survivors was determined using receiver operating characteristic analysis.

Results

The Chinese version of the PSQI had a Cronbach alpha of 0.71, with an intraclass correlation coefficient of 0.90. Childhood cancer survivors showed significantly lower mean PSQI scores than children with cancer, and significantly higher mean scores than healthy counterparts. This reflected that childhood cancer survivors had a better sleep quality than children with cancer, but a poorer sleep quality than healthy counterparts. We observed positive correlations between PSQI and CES-DC scores and between PSQI and FS-A/FS-C scores, but a negative correlation between PSQI and PedsQL scores. The results supported that the Chinese version of the PSQI showed convergent validity. Confirmatory factor analysis showed that the translated PSQI data best fit a three-factor model. The best cutoff score to detect insomnia was 5, with a sensitivity of 0.81 and specificity of 0.70.

Conclusion

The Chinese version of the PSQI is a reliable and valid instrument to assess subjective sleep quality among Hong Kong Chinese childhood cancer survivors. The validated PSQI could be used in clinical settings to provide early assessments for sleep disruption. Appropriate interventions can therefore be provided to minimize its associated long-term healthcare cost.

Trial registration This study was registered in ClinicalTrials.gov with the reference number NCT03858218.

Neurology of Sleep

Healthy sleep, including proper amounts in the 24-hour day/night period, is crucial for developing children. Sleep development in infants and children is characterized by increased amounts of sleep, including rapid eye movement and non-rapid eye movement (NREM) slow-wave sleep. Expected changes as well as deviations may contribute to sleep problems, which are common in typically developing children and very common in those with neurodevelopmental disorders and often are chronic. Periodic screening of children for sleep problems is important for timely and effective management of these.

Pathways to adolescents' health: chronotype, bedtime, sleep quality and mental health

The strong relationship between sleep and health is defined in the literature. While the need for sleep increases in adolescence with the effect of physiological and hormonal changes, the studies have highlighted the serious sleeping problems of adolescents compared to childhood and adulthood. This study aimed to examine the relationship between chronotype, bedtime, sleep quality and mental health among adolescents. This research was a descriptive-relational study. A total of 1083 students constituted the group of the research. The data were collected through the Morningness-Eveningness Questionnaire (MEQ) and General Health Questionnaire and a questionnaire consisting of some questions about sleep. In the evaluation of data, multiple regression, mediation and path analysis were performed. Age, having problems affecting sleep, difficulties falling asleep, sharing the room with someone else and lack of leisure activities were related to bedtime. It was found that determinants of sleep quality were the variables related to sleep itself. Being a male student, having problems affecting sleep, difficulties falling at sleep, waking up during the night, getting support in the morning for waking up and lack of leisure activities negatively affected mental health. MEQ scale was interpreted as a determinant of sleep time, sleep quality, and mental health level. Although the MEQ score directly affected sleep quality, bedtime had a partial mediation role between MEQ score and sleep quality. Sleep quality had a full mediation role between MEQ score and mental health score. School health workers, especially nurses, should consider chronotype-focused measures to improve adolescents' sleep quality and psychosocial health.

Sleep duration and mood in adolescents: an experimental study

STUDY OBJECTIVES

This study examines the relationship between experimentally manipulated sleep duration and mood in adolescents.

METHODS

Thirty-four adolescents (20 male), aged 15-17 years, lived in a sleep laboratory for 10 days and 9 nights. They were allocated to one of three sleep "doses" for five consecutive nights for 5, 7.5, or 10 h sleep opportunity per night. Two baseline nights and two recovery nights entailed 10 h sleep opportunity per night. Mood was measured every 3 h during wake using unipolar visual analogue scales measuring the mood states "depressed," "afraid," "angry," "confused," "anxious," "happy," and "energetic."

RESULTS

Mixed models analyses with post hoc comparisons revealed that participants in the 5-h group, but not the 7.5- or 10-h groups, reported being significantly more depressed, angry, and confused during sleep restriction than at baseline. Adolescents were significantly less happy and energetic during sleep restricted to 5 h and significantly less energetic during sleep restricted to 7.5 h. When adolescents had 10 h sleep opportunities their happiness significantly increased. No statistically significant effects of sleep restriction were found for fear or anxiety, although small-to-moderate effects of sleep restricted to 5 or 7.5 h were found. Two nights of recovery sleep was not sufficient to recover from increased negative mood states for the 5-h group, although recovery occurred for positive mood states.

CONCLUSIONS

Given the prevalence of insufficient sleep and the rising incidence of mood disorders and dysregulation in adolescents, these findings highlight the importance of sufficient sleep to mitigate these risks.

Homeostatic Response to Sleep Restriction in Adolescents

The high prevalence of chronic sleep restriction in adolescents underscores the importance of understanding how adolescent sleep is regulated under such conditions. One component of sleep regulation is a homeostatic process: if sleep is restricted, then sleep intensity increases. Our knowledge of this process is primarily informed by total sleep deprivation studies and has been incorporated in mathematical models of human sleep regulation. Several animal studies, however, suggest that adaptation occurs in chronic sleep restriction conditions, showing an attenuated or even decreased homeostatic response. We investigated the homeostatic response of adolescents to different sleep opportunities. Thirty-four participants were allocated to one of three groups with 5, 7.5 or 10 h of sleep opportunity per night for 5 nights. Each group underwent a protocol of 9 nights designed to mimic a school week between 2 weekends: 2 baseline nights (10 h sleep opportunity), 5 condition nights (5, 7.5 or 10 h), and two recovery nights (10 h). Measures of sleep homeostasis (slow-wave activity and slow-wave energy) were calculated from frontal and central EEG derivations and compared to predictions derived from simulations of the homeostatic process of the two-process model of sleep regulation. Only minor differences were found between empirical data and model predictions, indicating that sleep homeostasis is preserved under chronic sleep restriction in adolescents. These findings improve our understanding of effects of repetitive short sleep in adolescents.

A Longitudinal Study of Subjective Daytime Sleepiness Changes in Elementary School Children Following a Temporary School Closure Due to COVID-19

Excessive daytime sleepiness is increasingly being recognized as a major global health concern. However, there have been few studies related to sleepiness and its associated factors in elementary school children. In Japan, all schools were closed from February to May 2020 to prevent coronavirus disease 2019 (COVID-19) outbreaks. The aim of this study was to identify changes in the subjective sleepiness of pupils during the 1.5-year period and to elucidate factors associated with changes in sleepiness. Questionnaire surveys about pupils’ sleep habits and the Japanese version of the Pediatric Daytime Sleepiness Scale (PDSS-J) were conducted longitudinally at one elementary school in June 2019, January 2020, and June 2020. The average ∆PDSS score was 0.94 ± 5.51 (mean ± standard deviation) from June 2019 to January 2020 and −1.65 ± 5.71 (t[498] = 6.13, p < 0.01) from January 2020 to June 2020. Univariate and multivariate logistic regression analyses revealed that decreasing social jetlag was associated with decreasing PDSS scores (OR = 0.77, 95% CI: 0.62–0.96, p = 0.02) during the school closure. A less restrictive school schedule secondary to a COVID-19-related school closure decreased sleepiness in children and was associated with decreasing social jetlag.

Normal Sleep in Children and Adolescence

Adequate sleep is essential for healthy development in childhood and adolescence. Healthy sleep contributes to good physical health, immune function, mental health, and academic performance. The regulation and architecture of sleep change greatly across childhood and adolescence, and the ability to obtain sufficient sleep is impacted by a range of factors that change with maturation. This article describes normal sleep across childhood and adolescence and discusses some of the most common barriers to adequate sleep, including early school start times, technology use, and changes to circadian rhythms, and sleep homeostasis across puberty.

Morningness in German and Spanish students: a comparative study

Humans show pronounced individual differences in circadian orientation. Transcultural comparisons are interesting since biological (or environmental) factors together with cultural ones may contribute to differences in morningness–eveningness. We compared Spanish and German undergraduates using the Composite Scale of Morningness (CSM) to assess circadian preferences. Confirmatory and multiple groups confirmatory factor analysis were used to assess factor structure and structural invariance across countries. The results showed that a three‐factor model of morningness best characterises the CSM structure of both samples. Partial factorial invariance (factor loadings) across countries was demonstrated for the factors ‘morningness’ and ‘morning alertness’. Scores of both factors were higher in German students. Potential cultural and biological explanations for the differences are discussed. Copyright © 2007 John Wiley & Sons, Ltd.

Development and Validation of the Adolescent Insomnia Questionnaire

OBJECTIVE

Insomnia is a highly prevalent sleep disorder that is particularly common among adolescents with health conditions. We aimed to develop and validate a brief screening measure of insomnia in adolescents that can be used across clinical and community samples. We hypothesized that we would identify evidence supporting reliability, convergent/discriminant validity, and that we would determine preliminary clinical cutoff scores.

METHODS

A team of experts in behavioral sleep medicine developed a 13-item brief screening measure of insomnia in adolescents (Adolescent Insomnia Questionnaire [AIQ]). We evaluated the psychometric properties of the AIQ in a sample of 315 youth (11-18 years old, Mean = 14.90, SD = 2.02; 64% female) who had chronic pain (n = 37), headache (n = 170), insomnia diagnosed by a sleep specialist (n = 22), or were otherwise healthy (n = 86).

RESULTS

Using Exploratory and Confirmatory Factor Analysis, we identified three subscales consistent with major diagnostic criteria of insomnia. As expected, the measure showed strong reliability through high internal consistency (α =.91). We also found strong convergent validity through expected positive relationships between the AIQ and self-report measures of sleep disturbance, and divergent validity via weak relationships with parent-report of snoring. Results of receiver operating characteristic (ROC) identified a clinical cutoff score that may assist in clinical decision making.

CONCLUSIONS

We found that the AIQ has sound psychometric properties in a large heterogeneous sample of treatment-seeking youth and youth from the community. The AIQ can quickly screen adolescent insomnia and could address an important clinical need in identifying youth in need of insomnia treatment in pediatric practice settings.

Impact of sleep restriction on affective functioning in adolescents with attention-deficit/hyperactivity disorder

BACKGROUND

Shortened sleep and affective disturbances are both prevalent in adolescents with attention-deficit/hyperactivity disorder (ADHD), yet the causal link between these domains has not been examined. This study investigated whether shortened sleep duration is causally linked to affective functioning in adolescents with ADHD.

METHODS

Participants were 48 adolescents (75% male) aged 14-17 years with ADHD who successfully completed a three-week sleep protocol using an experimental crossover design. The protocol included a phase stabilization week, followed, in randomized counterbalanced order, by one week of sleep restriction (6.5 hr in bed) and one week of sleep extension (9.5 hr in bed). Sleep was monitored with objective actigraphy, and all participants included in this study obtained ≥1 hr actigraphy-measured sleep duration during extension compared to restriction. Parents and adolescents provided daily ratings of positive and negative affect during the extension and restriction conditions. Ratings of affect, internalizing symptoms, and emotion regulation were collected at laboratory visits conducted at the end of each week.

RESULTS

Both parents and adolescents reported greater depressive symptoms and lower positive affect during restriction compared to extension. Parents also reported greater negative affect and emotion dysregulation among adolescents during sleep restriction than extension. No effects were found for parent- or adolescent-reported anxiety symptoms or for adolescent-reported emotion regulation or negative affect.

CONCLUSIONS

Findings from this study provide the first evidence that shortened sleep duration is a causal contributor to the affect and mood disturbances frequently experienced by adolescents with ADHD, particularly as observed by parents. Targeting sleep may be important to reduce affective disturbances in adolescents with ADHD.

Open trial of the Parent Behavior Change Intervention (PBC-I): Study protocol

OBJECTIVE

Parents have profound impacts on adolescents' health behaviors. Yet parents receive minimal training in the elements of conversations that optimally inspire their children toward engaging in healthy behaviors. The current study examines a novel interpersonal target: parent-adolescent conversations about adolescent health behavior change. Derived from advances in the science of behavior change, the Parent Behavior Change Intervention (PBC-I) contains conversational elements (e.g., behavior change techniques, positive communication strategies) hypothesized to reduce parent-adolescent coercion and conflict and facilitate upward spirals of healthy behavior change in adolescents.

METHOD/DESIGN

The first phase of the study involves the development of the PBC-I in a small case series (N = 12 dyads). The second phase involves an open trial of the PBC-I (N = 36 dyads). Adolescents will receive six 50-min sessions of the Transdiagnostic Sleep and Circadian Intervention to improve sleep while their parents receive six50-min sessions of the PBC-I. Parent-adolescent dyads will be assessed before and after the intervention. The primary analysis will examine whether postintervention use of behavior change techniques and positive communication strategies by parents is higher than preintervention use and whether increased use by parents predicts more positive conversational behaviors, less parent-adolescent conflict, higher adolescent motivation for change, and improved adolescent sleep.

DISCUSSION

This research provides an initial test of the hypothesis that improving the parent-adolescent conversation will improve adolescent sleep health behavior. While sleep-related health behaviors are the focus of this study, the research is designed to be relevant to a broad range of health behavior change in young people. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Neural activity moderates the association between sleep and risky driving behaviors in adolescence

The biological, environmental, and psychosocial changes that occur in adolescence engender an increase in risk taking often linked to the high rates of motor vehicle crashes amongst young drivers. Most U.S. adolescents suffer from poor sleep, which is known to exacerbate the risk of driving crashes; however, research has yet to uncover a neurobiological link between sleep and risky driving in adolescence. Here, we examined potential moderators of the sleep-risk relation in fifty-six adolescents (14-18y/o) as they completed a driving task during fMRI. While poor sleep was associated with increased risky driving (i.e., running more yellow lights), good sleep emerged as a novel buffer against risky driving in lower sensation-seeking adolescents. Neural activity in the ventral striatum (VS), a key node of the risk-taking circuit, also moderated the sleep-risk association: sleep was related to risk-taking in individuals demonstrating high, but not low, VS response during risky decision-making, suggesting that reward-related neural response may underly the connection between sleep and risk-taking in adolescence. This study sheds light on the risk of driving crashes in youth by highlighting sleep as both an exacerbator and a buffer of risky driving in adolescence. Taken together, these results underscore the importance of improving adolescent sleep.

Classifying Pubertal Development Using Child and Parent Report: Comparing the Pubertal Development Scales to Tanner Staging

PURPOSE

This project investigated internal consistency and test-retest reliability of the frequently used Pubertal Development Scale (PDS) and compared parent and child reports with clinician-rated Tanner staging.

METHODS

Using a repository of data collected from 1995 to 2016, 252 participants (aged 7.8-17.7 years) provided self- and parent-reported PDS and received Tanner staging by a certified health care professional within 30 days. Internal consistency and test-retest reliability statistics were evaluated for 56 children across two assessments occurring within 6 months. Comparisons with Tanner staging involved examining concurrent validity and calibration analysis using data from 233 child and 252 parental ratings.

RESULTS

Self- and parent-reported PDS demonstrated good internal consistency, with Cronbach's alpha .91-.96; high test-retest reliability was confirmed with intraclass correlation coefficient .81-.92. The association of Tanner stage with self- and parent-reported PDS was moderate to high; Kendall's Tau ranged from .67 to .76, and intraclass correlation coefficient ranged from .73 to 83. The absolute agreement of Tanner stage with self- and parent-reported PDS was low; Cohen's Kappa ranged from .20 to .37. However, combining pubertal scores into three stages of development (pre/early-, mid-, and late/post-pubertal) improved interrater agreement across measures (κ = .65, 95% confidence interval = .57-.73).

CONCLUSIONS

The present study shows that the PDS is reliable and generally tracks with Tanner staging (for both self and parent report). Low absolute agreement indicates that PDS categories do not map directly to specific Tanner stages, partly because a premature adrenarche is often misinterpreted by parents and pediatricians alike. However, three broad categories showed better agreement and are generally adequate for most applications in child and adolescent research.

Later high school start times associated with longer actigraphic sleep duration in adolescents

Study Objectives

High school start times (SSTs) directly impact adolescents' sleep timing and duration. This study investigated the associations between SSTs and actigraphically-measured 24-hour sleep duration, sleep onset, sleep offset and sleep quality.

Methods

This study included 383 adolescents (Mage = 15.5, SDage = 0.6 years) participating in the age 15 wave of the Fragile Families & Child Wellbeing Study, a national birth cohort study sampling from 20 large US cities. Multilevel models used daily observations (N = 1116 school days, Mdays = 2.9, SDdays = 1.4 per adolescent) of sleep and SSTs from concordant daily diary and actigraphy.

Results

A diverse range of SSTs were included in our analyses (MSST = 08:08, SDSST = 39 minutes, RangeSST = 06:00-11:05), and are presented in the following categories for ease of interpretation: before 07:30, 07:30-07:59, 08:00-08:29, and 08:30 or later. Adolescents starting school at 08:30 or later exhibited significantly longer actigraphically-assessed 24-hour sleep duration (by 21-34 minutes, p < .05) and later sleep offset (by 32-64 minutes, p < .001) when compared with the adolescents grouped by earlier SSTs. SSTs were also analyzed continuously for comparison with existing literature, and results indicated that every 1-hour delay in SST was significantly associated with 21 minutes longer 24-hour sleep duration (p < .001), 16 minutes later sleep onset (p < .01), and 39 minutes later sleep offset (p < .001). All models controlled for covariates including socioeconomic status.

Conclusion

These findings support pediatric and public health expert recommendations for SSTs after 08:30. In our diverse national urban sample, adolescents with SSTs at 08:30 or later, compared with adolescents with earlier SSTs, had significantly longer actigraphy-measured sleep.

Four-Year Trends in Sleep Duration and Quality: A Longitudinal Study Using Data from a Commercially Available Sleep Tracker

Background

Population estimates of sleep duration and quality are inconsistent because they rely primarily on self-reported data. Passive and ubiquitous digital tracking and wearable devices may provide more accurate estimates of sleep duration and quality.

Objective

This study aimed to identify trends in sleep duration and quality in New York City based on 2 million nights of data from users of a popular mobile sleep app.

Methods

We examined sleep duration and quality using 2,161,067 nights of data captured from 2015 to 2018 by Sleep Cycle, a popular sleep-tracking app. In this analysis, we explored differences in sleep parameters based on demographic factors, including age and sex. We used graphical matrix representations of data (heat maps) and geospatial analyses to compare sleep duration (in hours) and sleep quality (based on time in bed, deep sleep time, sleep consistency, and number of times fully awake), considering potential effects of day of the week and seasonality.

Results

Women represented 46.43% (1,003,421/2,161,067) of the sample, and men represented 53.57% (1,157,646/2,161,067) of individuals in the sample. The average age of the sample was 31.0 years (SD 10.6). The mean sleep duration of the total sample was 7.11 hours (SD 1.4). Women slept longer on average (mean 7.27 hours, SD 1.4) than men (mean 7 hours, SD 1.3; P<.001). Trend analysis indicated longer sleep duration and higher sleep quality among older individuals than among younger (P<.001). On average, sleep duration was longer on the weekend nights (mean 7.19 hours, SD 1.5) than on weeknights (mean 7.09 hours, SD 1.3; P<.001).

Conclusions

Our study of data from a commercially available sleep tracker showed that women experienced longer sleep duration and higher sleep quality in nearly every age group than men, and a low proportion of young adults obtained the recommended sleep duration. Future research may compare sleep measures obtained via wearable sleep trackers with validated research-grade measures of sleep.

Sleep in relation to psychiatric symptoms and perceived stress in Swedish adolescents aged 15 to 19 years

BACKGROUND

Sleep affects psychiatric health and perceived stress during adolescence.

OBJECTIVE

The first aim of this study was to investigate the prevalence of poor sleep in a sample of Swedish adolescents aged 15 to 19 years. The second aim was to investigate correlations between: a) sleep and psychiatric symptoms and; b) sleep and perceived stress. The third aim was to examine possible sex differences in sleep.

METHOD

In 2011, a total of 185 Swedish adolescents (aged 15 to 19 years) from two upper secondary schools participated in this cross-sectional study. We used three different psychometric scales: Pittsburgh Sleep Quality Index (PSQI), Symptoms Checklist (SCL-90), and Perceived Stress Scale (PSS) to measure sleep, general psychiatric health and perceived stress.

RESULTS

In total, 76% of the female students and 71% of the male students had poor overall sleep quality. A large majority, 93%, reported daytime dysfunction and 60% reported problems staying awake during daily activities. The correlation between sleep and general psychiatric health was 0.44 and the correlation between sleep quality and perceived stress was 0.48. Female students reported significantly more sleep disturbances than male students do.

CONCLUSIONS

Three out of four of the upper secondary school students presented with poor overall sleep that associated with psychiatric symptoms and perceived stress. These findings add to results from earlier studies and imply that interventions to improve sleep in adolescents, individually as well as on a societal level, should be considered as one way of trying to impact the observed rising numbers of psychiatric complaints. Such interventions may improve mental and somatic health in adolescents and prevent the development of psychiatric and stress-related symptoms. Further studies of possible methods, and their implementation, for improving sleep in adolescents should be of high priority.

Associations Between Sleep Hygiene and Sleep Problems in Adolescents With ADHD: A Cross-Sectional Study

Objective: To determine whether self-reported sleep hygiene practices are associated with self- and parent-reported behavioral sleep problems in adolescents with ADHD. Method: Participants included 79 adolescents with ADHD (13-17 years) and their parents. Adolescents were asked to report on their sleep hygiene (Adolescent Sleep Hygiene Scale) and sleep (Adolescent Sleep Wake Scale). Parents also reported on their adolescent's sleep (Sleep Disturbance Scale for Children). Results: Poorer sleep hygiene was associated with higher total self-reported behavioral sleep problems and most self-reported sleep problems: falling asleep, reinitiating sleep, and returning to wakefulness. The association was also apparent for total parent-reported behavioral sleep problems, problems with initiating and maintaining sleep, and excessive somnolence. Conclusion: This study demonstrates small-to-moderate relationships between poor sleep hygiene practices and sleep problems in adolescents with ADHD, by both self- and parent-report.

Pubertal Development Measurement in Children With and Without Autism Spectrum Disorder: A Comparison Between Physical Exam, Parent- and Self-Report

Adolescence is a time of remarkable biopsychosocial change, which may be particularly challenging for youth with autism spectrum disorder (ASD), necessitating enhanced understanding and accurate assessment of pubertal maturation. The study compared physical examination to parent- and self-report measures in 200 participants (134 males and 66 females) ages 10.0-13.5 years. Both participants with typical development (TD, n = 78) and ASD (n = 122) were included. Concordance ranged from slight-to-fair for self-assessments (κ = .17-.32) and slight-to-moderate for parent-report (κ = .21-.44). Concordance of physical exam with self- and parent-report of the ASD group was somewhat lower than for the TD group. Findings indicate pubertal assessments by parent or child are not reliable indices of precise pubertal staging.

Differential and interacting effects of age and sleep restriction on daytime sleepiness and vigilance in adolescence: a longitudinal study

Study Objectives

There is contradictory evidence on whether sleep need decreases across adolescence. We investigated this question longitudinally with a dose-response design to test the effects of varied sleep durations on daytime sleepiness and on vigilance and to test whether these relations change with age across early and mid-adolescence.

Methods

Data from 76 participants who completed at least 2 years of the 3-year study are included in this report. Annually, participants ranging in age from 9.8 to 16.2 years completed three different time in bed (TIB) schedules each consisting of four consecutive nights of 7, 8.5, or 10 hours. Daytime sleepiness (multiple sleep latency test [MSLT]) and vigilance (psychomotor vigilance test [PVT]) were measured on the day following the fourth night of each TIB schedule.

Results

Electroencephalogram (EEG)-measured sleep durations changed linearly with TIB. MSLT-measured daytime sleepiness decreased with longer TIB and increased with age. The TIB and age effects interacted such that the TIB effect decreased with age. PVT performance improved with longer TIB and improved with age, but the benefit that increased TIB conferred on PVT performance did not change with age.

Conclusions

These results seem paradoxical because daytime sleepiness increased but vigilance improved with age. The significant age effect on the relation between TIB and sleepiness compared to the lack of an age effect on the relation between TIB and vigilance performance suggests different rates of maturation in underlying brain systems. We interpret these findings in relation to our model of adolescent brain development driven by synaptic elimination.