The influence of school time on sleep patterns of children and adolescents

ObjectiveThis epidemiological study evaluated the impact of school time on sleep parameters of children and adolescents.MethodsThis cross-sectional study involved 639 elementary and high school students (mean age 13.03 years, range 8–18, 58.5% female) from the south of Brazil. Participants answered the Morningness-Eveningness Questionnaire (MEQ), and were asked about their sleeping habits on weekdays and weekends. Sleep deficit was defined as the difference between sleep duration on weekdays and weekends.ResultsThe morning-school-time students presented significantly higher age, bedtime and wake up differences, sleep deficits, and social jetlag. The sleep deficit presented by girls was greater than that observed in boys of the same age. The difference between weekday and weekend waking times was also significantly greater in girls than in boys aged 13–18 years. Sleep deficit was significantly positively correlated with age and differences in wake up times, and significantly negatively correlated with MEQ scores, social jetlag, difference between weekday and weekend bedtimes, midpoint of sleep on weekends, and midpoint of sleep on weekends corrected for sleep deficit. A step-by-step multivariate logistic regression identified social jetlag, the difference between waking times on weekdays and weekends, and the midpoint of sleep on weekends as significant predictors of sleep deficit (Adjusted R² = 0.95; F = 1606.87; p <0.001).ConclusionThe results showed that school time influences the sleep parameters. The association of school schedules and physiological factors influence the sleep/wake cycle.     

Sleep–wake habits and circadian preference in Mexican secondary school

ObjectiveThe current study aimed to determine the differences between sleep–wake habits and circadian preference in Mexican adolescents attending classes at a morning shift or an afternoon shift.MethodsThe sample consisted of 568 students of a secondary school in Reynosa, northeastern Mexico, of whom 280 were boys and 288 were girls (mean age 14.08 ± 0.72 years, age range 13–16 years). In the morning shift, 287 students attend classes on a schedule from 7:30 to 13:00 and the afternoon shift, 281 students, on a schedule from 13:20 to 19:00. Students completed a general information questionnaire, the Sleep Timing Questionnaire and the Spanish version of the Morningness–Eveningness Questionnaire.ResultsThe adolescents who attended the morning shift had earlier bedtime and waking time, but shorter sleep duration than those who attended the afternoon shift. Those oriented to eveningness had later bedtime, waking time, and a shorter sleep duration than those oriented to morningness. Two interactions were found between school shift and chronotype. First, with regard to waking time during weekdays, students who attended the afternoon shift and were oriented to eveningness woke up later than those who attended the morning shift and were oriented to eveningness; during weekdays, there were no differences between the waking time of morning-type and evening-type students who attended the morning shift. Second, with regard to sleep duration on weekdays, students who attended the morning shift and were oriented to eveningness had the shortest sleep duration. Furthermore, there were no differences between sleep duration on weekdays in evening-type and morning-type students of the afternoon shift.ConclusionAdolescents who attend classes in the morning shift and are oriented to eveningness are the most sleep deprived. Those who attend the afternoon shift will have optimal sleep duration, regardless of their circadian preference.     

The relation of objective sleep patterns, depressive symptoms, and sleep disturbances in adolescent children and their parents: A sleep-EEG study with 47 families

ObjectivesNumerous studies have shown that the sleep and well-being of children and their parents are closely related. Previous studies have relied on subjective sleep data and have focused mostly on younger preadolescent children. The aim of the present study was therefore to investigate the relationship between the sleep patterns of adolescents and those of their parents using objective assessment of sleep.MethodsForty-seven families took part in this study. The sample comprised 80 adolescents (age: 16.3 ± 2.0 years; 44 males/36 females), 47 mothers (age: 49.5 ± 4.0 years), and 39 fathers (age: 50.8 ± 5.1 years). All participants individually completed questionnaires related to psychological functioning and sleep. Sleep-EEGs were assessed for all family members in their homes.ResultsAdolescents' and parents' objective sleep patterns were associated. In particular, the sleep continuity and architecture of adolescents and their mothers were strongly related. Additionally, significant relationships between objectively assessed sleep patterns, subjective sleep disturbances, depression scores and family climate held true for equally adolescents and mothers. Also, substantial links were found between adolescents' and parents' subjective sleep disturbances, depressive symptoms, and perceived family climate.ConclusionThe present findings document objectively for the first time the existence of relationships between adolescents' sleep and well-being and parents' sleep and well-being. These relationships were apparent regardless of whether subjective or objective sleep data were considered. The overall pattern of results strongly indicates that adolescents' sleep and well-being and family functioning are related.     

Risk factors associated with short sleep duration among Chinese school-aged children

ObjectivesTo examine risk factors regarding short sleep duration among Chinese school-aged children.MethodsA random sample of 20,778 children aged around 5–11 years participated in a cross-sectional survey, which was conducted in eight cities of China in 2005. A parent-administered questionnaire was used to collect information on children’s sleep duration and possible related factors from eight domains. Short sleep duration was defined as total sleep duration <9 h per day.ResultsIn all, 28.3% of the sampled children slept <9 h per day. The multivariate logistic regression identified, after adjusting for demographic and socioeconomic variables, factors associated with short sleep duration: more television viewing during weekdays (OR = 1.21, p = 0.004), more frequent computer/internet using (OR = 1.17, p = 0.006), earlier school starting time (OR = 1.10, p = 0.020), more time on homework during weekdays (OR = 1.66, p < 0.001) and weekends (OR = 1.14, p = 0.001), poor bedtime hygiene (e.g., having drinks with caffeine after 6:00PM [OR = 1.22, p < 0.001], doing exciting activities during bedtime [OR = 1.16, p < 0.001], and irregular bedtime [OR = 1.55, p < 0.001]), and shorter sleep duration of parents (mother: OR = 1.31, p < 0.001 for sleep duration <6 h and OR = 1.24, p = 0.006 for 6–8 h; father: OR = 1.52, p < 0.001 for <6 h and OR = 1.19, p < 0.001 for 6–8 h).ConclusionsFactors associated with sleep duration covered multidimensional domains among school-aged children. Compared to sleep environments and chronic health problems, school schedules, lifestyle patterns, and parents’ sleep habits had greater impact on children’s sleep duration, indicating the existing chronic sleep loss in school children could be, at least partly, intervened by reducing the use of visual technologies, by changing the school schedules, by improving the sleep hygiene routine, and by regulating parents’ sleep habits.     

Protective and risk factors associated with adolescent sleep: findings from Australia,Canada, and The Netherlands

BackgroundSleep is vital for adolescent functioning. Those with optimal sleep duration have shown improved capacity to learn and decreased rate of motor vehicle accidents. This study explored the influence of numerous protective and risk factors on adolescents' school night sleep (bedtime, sleep latency, total sleep time) simultaneously to assess the importance of each one and compare within three countries.MethodOnline survey data were collected from Australia, Canada, and The Netherlands. Overall, 325 (137 male), 193 (28 male), and 150 (55 male) contributed to data from Australia, Canada, and The Netherlands, respectively (age range 12–19 years).ResultsRegression analyses showed mixed results, when comparing protective and risk factors for sleep parameters within different countries, with combined behavioural factors contributing to small to large shared portions of variance in each regression (9–50%). One consistent finding between countries was found, with increased pre-sleep cognitive emotional sleep hygiene related to decreased sleep latency (beta = −0.25 to −0.33, p < 0.05). Technology use (mobile phone/Internet stop time) was associated with later bedtime, or less total sleep, with the strength of association varying between device and country.ConclusionResults indicate that when designing interventions for adolescent sleep, multiple lifestyle factors need to be considered, whereas country of residence may play a lesser role.     

Sleep patterns among rural Chinese twin adolescents

ObjectiveTo examine sleep patterns and influencing factors (age, gender, Tanner Stage, weekday vs. weekend, and pre-sleep activity) among rural Chinese adolescents.MethodsThis is a prospective study among 621 adolescents aged 11–20 years (341 males) using both a questionnaire and sleep diary to obtain bedtime, wake-up time, sleep latency, and total sleep time (TST).ResultsThe median TST was 8.6 h on weekdays and 9.4 h on weekends. Despite absence of late night social pressure and computers, a U-shaped TST pattern was observed across age and Tanner Stage, with a nadir around age 15–16 years or Tanner IV. Bedtimes became progressively later with age and Tanner Stage, while wake-up time was considerably earlier for school students or up to Tanner IV. Later wake-up times and longer TST on weekends were seen in school students, but not in non-school adolescents (>17 years). Pre-sleep activity, like reading or studying, was related to later bedtime, earlier wake-up time, and shorter TST in both genders.ConclusionsAge, Tanner Stage, and pre-sleep activity affected sleep patterns in this sample of rural Chinese adolescents. Later bedtime coupled with earlier wake-up time associated with academic demand appear to be important contributors to sleep loss among school students.     

The impact of COVID-19 related school shutdown on sleep in adolescents: a natural experiment

ObjectiveDuring the outbreak of the COVID-19 pandemic in 2020, high schools closed or transitioned to remote teaching. The aim of this study was to describe how the COVID-19 related school shutdown impacted the sleep behaviors of typically developing adolescents.MethodsA qualitative study was conducted between April 28 and June 3, 2020 with 45 adolescents using one-on-one semi-structured phone interviews.ResultsThe “natural experiment” caused by the shutdown of schools due to the COVID-19 pandemic led to a 2-h shift in the sleep of typically developing adolescents, longer sleep duration, improved sleep quality, and less daytime sleepiness compared to those experienced under the regular school-time schedule.DiscussionThese findings are consistent with previous studies showing that delaying high school start times could be an effective way to extend sleep duration, improve sleep quality, reduce daytime sleepiness and lower adolescents' stress during the school year. As many countries look for ways to reduce the number of interactions between students in schools so that physical distancing is feasible, following teens’ delayed sleep biology could offer an affordable solution. For example, staggering arrival times by delaying school start time for older adolescents compared with younger adolescents can reduce the total number of students attending school at the same time. This strategy offers a practical means to reduce school density and the number of interactions between students which are needed to reduce the potential transmission of COVID-19 in schools, while improving adolescents sleep health.     

Sleep duration and behavioral correlates in middle and high school students: a cross-sectional study in Zhejiang province,China

ObjectiveTo investigate the sleep duration and correlates from lifestyle, dietary and weight control behaviors in Chinese adolescents.MethodsData were from 2017 Zhejiang Youth Risk Behavior Survey. A total of 17059 adolescents were included in this study and sleep duration and other behaviors information was collected via a self-reported questionnaire. Regression coefficients (β), calculated by multivariable linear regression, were used to assess the effects of related behaviors on sleep duration, adjusting for potential confounding factors.ResultsOverall, the mean sleep duration in adolescents was 7.99 h. Ever smoking, engaging in moderate physical activity and muscle strengthening activity, attending physical education classes, and watching television were significantly associated with longer sleep duration (P _trend ≦0.01 for all). Adolescents with breakfast, fruits, vegetables, milk and soft drinks intake were more likely to have longer sleep duration (P _trend <0.05 for all). Weight perception of overweight and weight control behaviors including exercising and eating less food, fewer calories were significantly associated with the short sleep duration (P _trend <0.05 for all).ConclusionChinese adolescents slept less than the counterparts in Western countries. Various lifestyle, dietary and weight control behaviors were associated with sleep duration.     

Annual longitudinal survey at up to five time points reveals reciprocal effects of bedtime delay and depression/anxiety in adolescents

ObjectiveTo investigate the longitudinal relationship between sleep habits and mental health in adolescents.MethodsMultipoint observation data of up to five years were employed from a prospective cohort study of sleep habits and mental health status conducted from 2009 to 2013 in a unified junior and senior high school (grades 7–12) in Tokyo, Japan. A total of 1078 students answered a self-report questionnaire, including items on usual bed and wake-up times on school days, and the Japanese version of the 12-item General Health Questionnaire (GHQ-12).ResultsLatent growth model (LGM) analysis, which requires three or more time point data, showed that longitudinal changes in bedtime and GHQ-12 score (or score for depression/anxiety) were significantly and moderately correlated (correlation coefficient = 0.510, p < 0.05). Another result of interest was that, using an autoregressive cross-lagged (ARCL) model, bedtime and the depression/anxiety score had reciprocal effects the following year: ie, bedtime significantly affects the following year's depression/anxiety, and vice versa. In addition, the analysis provided estimates of mutually predicted changes: one-hour bedtime delay may worsen the GHQ-12 score by 0.2 points, and one-point worsening of the score may delay bedtime by 2.2 minutes.ConclusionsBy using up to five multiple time point data, the present study confirms the correlational and reciprocally longitudinal relationship between bedtime delay and mental health status in Japanese adolescents. The results indicate that preventing late bedtime may have a significant effect on improving mental health in adolescents.     

Sleep and stress in adolescents: the roles of pre-sleep arousal and coping during school and vacation

Study objectivesThis study explored the relationship between stress and actigraphy-measured and self-reported sleep in adolescents during periods of restricted (school) and unrestricted (vacation) sleep opportunities. We further examined whether (1) cognitive pre-sleep arousal (PSA) mediated the relationship between stress and sleep onset latency (SOL), and (2) coping moderated the effect of stress on PSA.MethodsParticipants were 146 (77 females) adolescents (M = 16.2, SD = 1.0) recruited from the community. Actigraphy assessed daily sleep over the last week of a school-term and the following two-week vacation. The following self-report measures were administered during both school and vacation: the Pittsburgh Sleep Quality Index, Inventory of High-School Students Recent Life Experiences (stress), Pre-Sleep Arousal Scale, and the Brief COPE (coping).ResultsPath analyses showed that during both school and vacation, higher cognitive PSA mediated the relationship between higher stress and longer self-report SOL (p < 0.01). During vacation, higher PSA also mediated the relationship between higher stress and longer actigraphy SOL (p < 0.05). During vacation (but not school), problem-focused coping moderated the mediating effects of PSA (p < 0.05), such that more frequent use of coping was associated with weaker association between stress and cognitive PSA, and shorter actigraphy and self-report SOL.ConclusionsCognitive PSA and coping may be two modifiable factors influencing how stress affects adolescents' sleep onset. Interventions that reduce cognitive arousal at bedtime may therefore shorten adolescents’ sleep onset during both school and vacation. Further, the use of problem-focused coping strategies might be protective against the effects of stress on sleep onset, especially during vacation periods.Statement of significanceThis paper expands the understanding of the stress-sleep association in adolescents by examining the mediating role of cognitive pre-sleep arousal and the moderating effects of coping. By examining these associations during both school and vacation periods, findings are likely to be applicable to both restricted and relatively unconstrained sleep conditions. Practically, our findings suggest that interventions directed towards the reduction of cognitive pre-sleep arousal may improve adolescents' sleep onset latency. Additionally, fostering healthy coping, especially problem-focused coping strategies such as problem solving, may mitigate the effects of stress on adolescents' sleep.     

Daily light exposure,sleep–wake cycle and attention in adolescents from different urban contexts

Objectiveto compare daily light exposure, activity-rest rhythm, sleep–wake cycle (SWC) and attention in Brazilian students living in different levels of urbanization.Methods115 adolescents (74 girls), aged 14–18 years (mean 15.5 ± 0.7 years), from the first years of high school have participated. The SWC was evaluated by actimetry and a Sleep Diary for 10 days. Besides, the “Health and Sleep” Questionnaire, the Morningness and Eveningness Scale for adolescents, the Pittsburgh Sleep Quality Index, and the Pediatric Daytime Sleepiness Scale were answered. Attention was assessed by a Continuous Performance Task.ResultsIn the less urbanized region, there were a greater exposure to light during the day accompanied by a higher proportion of morning-types and less occurrence of excessive daytime sleepiness. Otherwise, in the more urbanized region, adolescents showed a trend to sleep less in weekdays and presented more irregularity in sleep duration between weekdays and weekend, with 83 ± 15% of sleep efficiency, 01:04 ± 1:30 h of WASO and 7 ± 6.7 awakenings per night on the weekdays, suggestive of poor sleep quality. Despite of this, they showed better attentional performance: more correct responses (tonic and phasic alertness, and sustained attention) and less omissions (for all components). Regardless of the degree of urbanization, there was partial sleep deprivation, irregular sleep schedules and poor sleep quality in adolescents.ConclusionsThe daily light exposure and activity-rest profiles, SWC and attention in adolescents varied according to the degree of urbanization. Besides, the negative impacts of early school starting times leading to sleep deprivation, irregular sleep times and poor sleep quality were observed irrespective of the degree of urbanization, reinforcing that the early school starting time at morning is a strong temporal challenge for teenagers, having negative impacts on cognition and academic performance.     

Similarities and differences between actigraphy and parent-reported sleep in a Hispanic and non-Hispanic White sample

ObjectiveDespite concerns about the inaccuracy of parents' reports of children's sleep, it remains unclear whether the bias of parents' reports varies across racial/ethnic groups. To address this limitation, the current study systematically investigated the concordance among parent-reported sleep questionnaires, sleep diaries, and actigraphy-based sleep in a sample of Hispanic and non-Hispanic White children.MethodsParents of 51 Hispanic and 38 non-Hispanic White children (N = 89; M_age = 6.46, SD = 0.62; 50.6% male) reported their child's bedtime and wake time on school days using sleep diaries and questionnaires. Children's sleep also was assessed with actigraphy for five consecutive school days.ResultsParents reported longer sleep duration, earlier bedtime, and later wake time using sleep diaries and questionnaires compared to actigraphy-based assessments. Larger discrepancies between diaries and actigraphy of sleep duration, and between questionnaires and actigraphy of wake time were found in non-Hispanic White children, compared to Hispanic children.ConclusionsAlthough parents tended to overestimate their child's sleep as compared to actigraphy, parents of Hispanic children may be more accurate in some estimates of children's sleep than parents of non-Hispanic White children. Researchers, clinicians, and parents should be aware of the potential biases in parents' reports and estimates of their child's sleep and that the degree of bias could vary across racial/ethnic groups.     

Adolescent sleep,distress, and technology use: weekday versus weekend

Background

In adolescents, technology use at bedtime is linked to disrupted sleep and psychological distress. Adolescents are known to sleep later on weekends compared to weekdays but whether this leads to greater technology use, and, hence, additional psychological distress is not known. At greater risk maybe adolescents with a late compared to early chronotype, that is a preference for late versus early sleep onset and offset times.

Method

Self-reported measures of sleep timing, chronotype (early, neither early nor late, late), technology medium (social media/texting, TV/streaming, and gaming), and psychological distress (DASS-21) were collected from 462 students attending one Australian high school.

Results

Technology use at bedtime was greater on weekends and especially in adolescents with a late chronotype. Social media/texting on weekends was predictive of delayed sleep onset times (β = .120), and shorter sleep (β = −.172). Shorter sleep on weekdays but not on weekends was associated with greater psychological distress. Technology medium and chronotype were not predictive of psychological distress.

Conclusions

This study confirmed that technology use and its impact on sleep differed on weekdays compared to weekends and that a late chronotype was associated with greater technology use. However, neither technology medium nor chronotype was found to affect psychological distress. While greater autonomy may be granted to adolescents over the weekend regarding sleep behaviour, young people, parents, and clinicians should be mindful of the link between technology use and sleep.     

Effects of sleep duration and weekend catch-up sleep on falling injury in adolescents: a population-based study

ObjectiveThis population-based study aimed to determine the effects of sleep deprivation and compensatory weekend catch-up sleep on the risk of falls in adolescents.MethodsData from the 2013 Korean Youth Risk Behavior Web-based Survey on 57,225 adolescents were investigated. Demographic, socioeconomic, sleep-related, health-related behavioral, and psychological variables were compared between fallers (n = 7346) and non-fallers (n = 49,879). Multivariate logistic regression analysis using a hierarchical model was carried out to identify sleep-related factors (eg, sleep duration, longer weekend catch-up sleep) independently contributing to the risk of falls.ResultsCompared to non-fallers, fallers were associated with a shorter sleep duration (p = 0.001) and later bedtimes on weekdays and weekends (p < 0.001). An average sleep duration of ≤ 5 h (odds ratio [OR] 1.23, 95% confidence interval [CI] 1.12–1.34) and of 6 h (OR 1.12, CI 1.03–1.21) were associated with an increased risk of falls. By contrast, an average sleep duration of ≥ 9 h (OR 0.90, CI: 0.82–0.99) and longer weekend catch-up sleep (OR 0.94, CI: 0.89–0.99) were associated with a decreased risk of falls.ConclusionOur results corroborate previous suggestions that short sleep duration is a major risk factor for falls among adolescents. Moreover, our study provided a novel finding that longer sleep duration and longer weekend catch-up sleep may have a protective effect against falls. Our findings have important public health implications that modifying school schedules to increase sleep duration could reduce unintentional falls and injuries in school-aged adolescents.     

Association between short time in bed,health-risk behaviors and poor academic achievement among Norwegian adolescents

ObjectiveTo investigate the prevalence of short time in bed (<8 h/day) and to examine the association between time in bed, overweight/obesity, health-risk behaviors and academic achievement in adolescents.MethodsThis study included a sample of adolescents (n = 2432) aged 15–17 years in the southern part of Norway (participation rate, 98.7%). A self-report questionnaire was used to assess time in bed, body mass index, dietary habits, physical activity habits, sedentary behavior, smoking and snuffing habits, and academic achievement.ResultsA total of 32.3% of the students reported short time in bed (<8 h/day) on an average school night. Several health-risk behaviors were associated with short sleep duration, including not being physically active for ⩾60 min for ⩾5 days/week (adjusted odds ratio, 1.33; 95% confidence interval, 1.05–1.68); using television/computer >2 h/day (1.63; 1.23–2.17); being a current smoker (2.46; 1.80–3.35) or snuffer (2.11; 1.57–2.85); having an irregular meal pattern (1.33; 1.05–1.68); intake of sweets/candy ⩾4 times/week (0.51; 0.32–0.83); and poor academic achievement (1.62; 1.26–2.09). All odds ratios were adjusted for sex, age and parental education.ConclusionsIn Norwegian adolescents, short time in bed is associated with several health-risk behaviors and poor academic achievement.     

Sleep duration and daytime sleepiness in a large sample of Brazilian high school adolescents

ObjectiveTo investigate the prevalence and main factors associated with short and long sleep duration and excessive daytime sleepiness in Brazilian adolescents.MethodsThis was a cross-sectional study of 11.525 students of both genders, aged 14–17 years, from the public high-school system. Sleep duration was assessed by self-report and <8 h of sleep per day was considered short sleep and >10 h, long sleep. Socio-demographic and behavioral factors were investigated through a purpose-built questionnaire and daytime somnolence was assessed by the Epworth sleepiness scale (ESS).ResultsThe overall prevalence of short and long sleep was 54.7% and 3.3%, respectively. Frequency of short sleep was lowest in the afternoon shift (38.2%) and highest in the morning shift (62.9%) and full-day students (70.0%). Insufficient sleep was more frequent in working (63.0%) than non-working adolescents (53.1%; p = 0.001) and among those who used their cell phone before bedtime (56.3%) compared to non-users (49.7%, p = 0.001). On average, ESS score was higher in subjects with short and long sleep (respectively, 9.7 ± 4.4 and 10.0 ± 4.5) compared to those with normal sleep duration (8.9 ± 4.2; p = 0.001).ConclusionInsufficient sleep and excessive daytime sleepiness are very common among urban high-school Brazilian adolescents. Full day and morning school shifts are associated with short sleep and daytime somnolence, suggesting later start times may have a role in reducing sleep loss in these subjects. Older age, work activity, and cell phone use before bedtime, are also risk factors for of short sleep in adolescents. Although less common, long sleep can also be associated with excessive daytime sleepiness.     

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

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

Sleep habits in adolescents of Saudi Arabia; distinct patterns and extreme sleep schedules

Background and Study ObjectivesThere is a need for comprehensive studies on adolescents' sleep habits in the Middle Eastern region. The aim of this study was to investigate the sleep–wake patterns, prevalence of excessive daytime sleepiness (EDS), and disturbed sleep among adolescents in Saudi Arabia and to identify the associated factors.MethodsThe study was a cross-sectional survey done on a random sample of 1035 high school students, ages 14–23 years, in Jeddah, Saudi Arabia. The response rate was 91%. Students filled a self-reported questionnaire that included sleep–wake questions, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Perceived Stress Scale, academic performance, and personal data.ResultsStudents slept an average of 7.0 hours on school nights, with an average delay of 2.8 and 6.0 hours in weekend sleep and rise times, respectively. Around 1 in 10 students stayed up all night and slept after returning from school (exhibiting a reversed sleep cycle) on weeknights. This pattern was more prevalent among boys and students with lower grade point averages. The prevalence of sleep disturbance was 65%, and EDS was found in 37% of the students. Predictors of EDS were school type, stress, napping and caffeine use, while gender was a predictor of disturbed sleep.ConclusionsAdolescents in Saudi Arabia showed a high percentage of poor sleep quality. Compared with adolescents from other countries, they had a larger delay in weekend sleep and rise times. An alarming reversed sleep cycle on weekdays is present and highlights the need for further assessment.     

Patterns and correlates of sleep duration in the Southern cohort community study

ObjectiveTo investigate whether race (African American (AA) and white) is associated with sleep duration among adults from low socioeconomic (SES) strata and whether SES status, lifestyle behaviors, or health conditions are associated with sleep duration within race-sex groups.MethodsThis cross-sectional study includes 78,549 participants from the Southern Community Cohort Study (SCCS). Averaged daily sleep duration was assessed by weighted averages of self-reported sleep duration on weekdays and weekends. Adjusted odds ratios (ORs) of very short (<5 h/day), short (5–6 h/day), and long sleep (≥9 h/day) associated with pre-selected risk factors in each race-sex group were determined by multinomial logistic models.ResultsThe prevalence of very short and short sleep was similar among AAs (6.2% and 29.1%) and whites (6.5% and 29.1%). Long sleep was considerably more prevalent among AAs (19.3%) than whites (13.0%). Very short sleep was associated with lower education and family income, with stronger associations among whites. Higher physical activity levels significantly decreased odds for both very short (OR = 0.80) and long sleep (OR = 0.78). Smoking, alcohol use, and dietary intake were not associated with sleep duration. Regardless of race or sex, very short, short, and long sleep were significantly associated with self-reported health conditions, especially depression (ORs were 2.06, 1.33, and 1.38, respectively).ConclusionsSleep duration patterns differed between AAs and whites from the underrepresented SCCS population with low SES. Sleep duration was associated with several socioeconomic, health behaviors, and health conditions depending on race and sex.     

Circadian typology and implications for adolescent sleep health. Results from a large,cross-sectional,school-based study

Study objectivesTo investigate circadian typology in a large, representative sample of Norwegian adolescents, and its implications for sleep health.MethodsThe sample included 3920 1^st year high school students aged 16–17 years. Respondents completed a web-based survey, including the short version of the Horne-Ostberg Morningness-Eveningness Questionnaire (rMEQ), the Munich Chronotype Questionnaire (MCTQ) and items on sleep-related behaviors (eg electronic media usage in bed, consumption of caffeinated beverages), sleep beliefs and daytime sleepiness. Data were analyzed using one-way ANOVAs and Chi-squared tests.ResultsIn all, 7.8% were categorized as morning, 52.3% as intermediate and 39.9% as evening types, respectively. Evening types had later sleep timing, longer sleep latency, more social jetlag and shorter school day sleep duration than morning types, with intermediate types displaying a sleep pattern between these two extremes. None of the circadian types met the minimum recommended amount of sleep on school nights (ie 8+ hours), and only morning types had a mean sleep duration of 7+ hours (7:19 h, nearly 1 h more than evening types who slept 6:20 h, p < 0.001). Evening types reported more use of electronic media in bed, more consumption of caffeinated beverages and more daytime sleepiness than the other circadian types. They were also less satisfied with their school day sleep duration and perceived it more difficult to change their sleep pattern.ConclusionsResults from this study suggest that eveningness represents a sleep health challenge for older adolescents.