Sleep characteristics, body mass index, and risk for hypertension in young adolescents

The mediating role of child delay of gratification in the link between early and prolonged poverty exposure and adolescent allostatic load

Early and prolonged exposure to poverty disrupts biological processes associated with the body's stress response system, leading to long-term negative health outcomes, including obesity, autoimmune disorders, and cardiovascular disease. Allostatic load (AL), a composite measure of chronic stress on the body, is a robust predictor of subsequent health outcomes. However, developmental research examining the associations of early poverty exposure with AL in adolescence, as well as the underlying mechanisms of influence is limited. Early poverty exposure also impedes healthy development of child self-regulation, which may increase risk for high AL in adolescence, but this mechanistic pathway has not yet been tested. We used data from the national Study of Early Child Care and Youth Development (SECCYD) to examine the longitudinal associations between prolonged poverty exposure in early childhood (0-3 years) and AL in adolescence (age 15). We also tested the mediating role of child delay of gratification, a behavioral measure of self-regulation (at age 54 months), in the potential association between early poverty exposure and adolescent AL. Accounting for model covariates (i.e., child biological sex and race-ethnicity) and individual differences in child delay of gratification, early and prolonged poverty exposure was significantly associated with higher AL at age 15. The indirect effect through child delay of gratification was not significant, but the individual pathways of the indirect effect were significant, and the overall direct association of early poverty exposure with adolescent AL was significant. Our findings show that prolonged exposure to poverty in early childhood (0-3 years) can have significant negative associations with both child delay of gratification (at 54 months) and AL (at age 15). Given that the detrimental impacts of poverty exposure can be detected at an early age, targeted prevention efforts (e.g., anti-poverty programs such as cash assistance programs) may be able to offset some of the risks of early poverty exposure on self-regulation and AL.

The gendered health consequences of persistent exposure to short sleep duration during adolescence

INTRODUCTION

Despite evidence that sleep duration is associated with adolescent health, there remain several gaps in the literature. Little is known about: (1) the extent to which persistent exposure to short sleep duration is associated with adolescent health and (2) whether this association varies by gender.

METHODS

Using six waves of longitudinal data from the 2011-2016 Korean Children and Youth Panel Survey (N = 6147), this study examined whether persistent exposure to short sleep duration is related to two adolescent health outcomes (overweight status and self-rated health). Fixed effects models were estimated to account for individual-level heterogeneity.

RESULTS

Short sleep duration was associated with being overweight and self-rated health in different ways for boys and girls. Gender-stratified analysis suggests that, for girls, the risk of being overweight increased for 5 years in a row as short sleep duration persisted. Prolonged short sleep duration also resulted in a continued decline in girls' self-rated health. For boys, persistent exposure to short sleep duration predicted a lower likelihood of being overweight up to the fourth year, but then began to recover. No association between persistent exposure to short sleep duration and self-rated health was observed for boys.

CONCLUSION

Persistent exposure to short sleep duration was found to be more harmful to the health of girls than boys. Promoting longer sleep duration during adolescence may be an effective intervention to improve adolescent health, especially for girls.

Associations between sleep characteristics and risk for high blood pressure among students aged 9-18: A cross-sectional study in China

OBJECTIVE

The aim was to investigate the association of multidimensional sleep indicators with high blood pressure (HBP) of Chinese students.

METHODS

Participants in this cross-sectional study included 11561 students aged 9-18. Sleep was characterized by sleep timing (e.g., bedtime), sleep duration and sleep consistency (e.g., bedtime/wake-up time deviations and social jet lag (SJL)). We used odds ratios (OR) and 95% confidence intervals (95% CI) to assess the relationship between sleep and HBP.

RESULTS

Primary school students who slept 8.00-9.00h had a lower risk of HBP compared with sleeping >10h (OR 0.370, 95%CI 0.208, 0.658), while junior middle school students reporting ≤8.00h on weekday night had a lower risk of HBP compared with sleeping >10h (OR 0.303, 95%CI 0.111, 0.829). Moreover, compared with deviations = 0h, the OR (95%CI) for wake-up time deviations <0h and bedtime deviations >0h in primary school students with HBP were 0.314 (0.125, 0.790) and 2.155 (1.205, 3.853). Furthermore, compared with SJL = 0h, senior high school students reporting SJL = 0.01-0.50h, SJL = 0.51-1.00h and SJL = 1.01-2.00h had greater risk of HBP (OR 1.566, 95%CI 1.039, 2.361; OR 1.760, 95%CI 1.177, 2.631; OR 1.660, 95%CI 1.124, 2.452, respectively). Bedtime at night was associated with HBP for three educational periods students, however, there was no significant association between mid-day nap and HBP.

CONCLUSIONS

Sleep timing, sleep duration and sleep consistency are associated with high blood pressure in children and adolescents.

Effect of Sleep Changes on Health-Related Quality of Life in Healthy Children: A Secondary Analysis of the DREAM Crossover Trial

IMPORTANCE

Little is known regarding the effect of poor sleep on health-related quality of life (HRQOL) in healthy children.

OBJECTIVE

To determine the effect of induced mild sleep deprivation on HRQOL in children without major sleep issues.

DESIGN, SETTING, AND PARTICIPANTS

This prespecified secondary analysis focused on HRQOL, a secondary outcome of the Daily Rest, Eating, and Activity Monitoring (DREAM) randomized crossover trial of children who underwent alternating weeks of sleep restriction and sleep extension and a 1-week washout in between. The DREAM trial intervention was administered at participants' homes between October 2018 and March 2020. Participants were 100 children aged 8 to 12 years who lived in Dunedin, New Zealand; had no underlying medical conditions; and had parent- or guardian-reported normal sleep (8-11 hours/night). Data were analyzed between July 4 and September 1, 2022.

INTERVENTIONS

Bedtimes were manipulated to be 1 hour later (sleep restriction) and 1 hour earlier (sleep extension) than usual for 1 week each. Wake times were unchanged.

MAIN OUTCOMES AND MEASURES

All outcome measures were assessed during both intervention weeks. Sleep timing and duration were assessed using 7-night actigraphy. Children and parents rated the child's sleep disturbances (night) and impairment (day) using the 8-item Pediatric Sleep Disturbance and 8-item Sleep-Related Impairment scales of the Patient-Reported Outcomes Measurement Information System questionnaire. Child-reported HRQOL was assessed using the 27-item KIDSCREEN questionnaire with 5 subscale scores and a total score. Both questionnaires assessed the past 7 days at the end of each intervention week. Data were presented as mean differences and 95% CIs between the sleep restriction and extension weeks and were analyzed using intention to treat and an a priori difference in sleep of at least 30 minutes per night.

RESULTS

The final sample comprised 100 children (52 girls [52%]; mean [SD] age, 10.3 [1.4] years). During the sleep restriction week, children went to sleep 64 (95% CI, 58-70) minutes later, and sleep offset (wake time) was 18 (95% CI, 13-24) minutes later, meaning that children received 39 (95% CI, 32-46) minutes less of total sleep per night compared with the sleep extension week in which the total sleep time was 71 (95% CI, 64-78) minutes less in the per-protocol sample analysis. Both parents and children reported significantly less sleep disturbance at night but greater sleep impairment during the day with sleep restriction. Significant standardized reductions in physical well-being (standardized mean difference [SMD], -0.28; 95% CI, -0.49 to -0.08), coping in a school environment (SMD, -0.26; 95% CI, -0.42 to -0.09), and total HRQOL score (SMD, -0.21; 95% CI, -0.34 to -0.08) were reported by children during sleep restriction, with an additional reduction in social and peer support (SMD, -0.24; 95% CI, -0.47 to -0.01) in the per-protocol sample analysis.

CONCLUSIONS AND RELEVANCE

Results of this secondary analysis of the DREAM trial indicated that even 39 minutes less of sleep per night for 1 week significantly reduced several facets of HRQOL in children. This finding shows that ensuring children receive sufficient good-quality sleep is an important child health issue.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12618001671257.

Sleep duration change from childhood to adulthood and adult depressive disorders in the Chinese population

BACKGROUND

Sleep deprivation may cause depressive disorders in both children and adults. However, the effects of sleep duration change from childhood to adulthood on adult depressive disorders are poorly documented. Using the China Family Panel Study (CFPS) data, we aimed to examine the association between sleep duration change from childhood to adulthood and adult depressive disorders in the Chinese population.

METHODS

Data were from 1172 children aged 10-15 years in 2010 who were followed up through 2018 based on the nationally representative and population-based CFPS. According to sleep duration in childhood and early adulthood, the sleep duration change was categorized into four groups: persistently insufficient sleep, sleep duration loss, sleep duration gain and persistently sufficient sleep.

RESULTS

After adjustment for potential covariates, compared with individuals with persistently sufficient sleep duration, those with sleep duration loss (OR = 1.98, 95% CI = 1.14-3.46) and persistently insufficient sleep (OR = 2.35, 95% CI = 1.43-3.88) had higher odds of depressive disorders in adulthood. In contrast, the odds of adult depressive disorders did not significantly increase in those with sleep duration gain (OR = 1.46, 95% CI = 0.88-2.41).

LIMITATIONS

Information on sleep duration was obtained through a questionnaire; the sample size of this study was not large; the generalizality of our findings to other populations should be caucious.

CONCLUSION

Persistently insufficient sleep duration and sleep duration loss from childhood to adulthood were associated with higher odds of adult depressive disorders, while those who were able to change their sleep duration from insufficient status to sufficient status didn't have an increased odds of adult depressive disorders.

Physical Activity and Executive Functions in Adolescents: The Mediating Role of Sleepiness

(1) Background: Both physical activity and sleepiness were found to influence the development of executive functioning. The present study aimed to address the effects of different levels of physical activity on adolescents' executive performance (i.e., working memory and inhibition), and the role of sleepiness in this relationship. It was hypothesized that a higher level of physical activity would be associated with better executive functioning, while this relationship was mediated (at least partially) by reduced sleepiness at school. (2) Methods: 212 adolescents aged from 10 to 17 were recruited, and they were requested to wear accelerometers for seven consecutive days to measure daily levels of physical activity. The Cleveland Adolescent Sleepiness questionnaire (CASQ) was used to assess sleepiness. The working memory and inhibition control were assessed to indicate executive functioning. (3) Results: It was found that sedentary activity was negatively associated with working memory performance, while light and moderate-to-vigorous physical activities were related to better working memory. The relationship between different levels of physical activity and working memory was mediated by reduced sleepiness at school. (4) Conclusions: Our findings provide nuanced evidence that the benefits of light and moderate-to-vigorous physical activity on cognitive development could be explained by reduced sleepiness at school.

Association between Free Sugars Intake and Excessive Daytime Sleepiness among Chinese Adolescents

This study aimed to investigate the prevalence of excessive daytime sleepiness (EDS) and explore the association between free sugars intake and EDS. In this cross-sectional study, a total of 1517 middle school students (808 boys and 707 girls) aged 12~14 years were recruited. The study was conducted in Changsha city, China. Adolescents completed an online questionnaire, including the Epworth Sleepiness Scale (ESS), sleep characteristics, a 12-item Food Frequency Questionnaire (FFQ), and other self-reported information. The ESS score ≥ ten was defined as EDS. The anthropometric indices, including height, weight, and waist circumference, were measured and recorded by uniformly trained assistants. Statistical analyses included the Chi-square test and binary logistic regression model. The mean ESS score and free sugars consumption were 6.8 ± 3.9 points and 53.1 ± 44.7 g/d, respectively. The prevalence of EDS among adolescents was 22.5%, and more girls than boys had EDS (26.1% vs. 19.4%, p < 0.05). An exceeded free sugars intake was positively associated with EDS, with the adjusted Odds Ratio (OR) with its 95% Confident Interval (95% CI) of 1.366 (1.060~1.761, p < 0.05). EDS and excessive consumption of free sugars are commonly found among Chinese adolescents. Further studies are needed to confirm whether free sugars restriction can be meaningful to improve daytime drowsiness in those with EDS.

Sleep problems in children and adolescents following traumatic life events

Rates of childhood trauma exposure are extremely high, with approximately 70% of children and adolescents experiencing at least one traumatic event. Among the most common non-specific consequences of stress and trauma are disruptions of sleep. Sleep problems, such as shorter sleep duration, difficulty falling asleep, frequent awakenings, nightmares, sleepless nights, and early-morning wakefulness appear to have a higher prevalence among children and adolescents following traumatic events. This review will illustrate the role of sleep problems in traumatized children and adolescents, and emphasize the need to consider a wide range of etiological mechanisms for these symptoms. However, the relationship of trauma exposure to sleep problems among children and adolescents needs further investigation in future research. Moreover, in view of the adverse consequences of long-term disrupted sleep on mental health outcomes following trauma, the need to effectively address sleep disturbances in traumatized children and adolescents is crucial.

EVIDENCE OF THE ASSOCIATION BETWEEN SLEEP DURATION AND BLOOD PRESSURE IN ADOLESCENTS: A SYSTEMATIC REVIEW

OBJECTIVE

To review the epidemiological evidence of the association between sleep duration and blood pressure in adolescents.

DATA SOURCES

We performed a systematic review of observational studies in Medline, Scopus, Lilacs, Web of Science, Science Direct databases and Virtual Libraries in English, Spanish and Portuguese published until September 2018. Studies were selected first by title and abstract, then by complete reading, according to the eligibility criteria. The reference list of selected articles was evaluated in order to retrieve relevant studies.

DATA SYNTHESIS

Initially, 1,455 articles were retrieved. After exclusion due to duplicity or not meeting the eligibility criteria, 13 articles were included in the review. Studies varied greatly in sample size (143 to 6,940 patients), methods of measuring blood pressure and sleep duration, cutoff points, categorization and adjustment of variables. The main evidence from the studies is that short sleep duration is associated with high blood pressure in adolescence, although the presence of association between high blood pressure and long sleep duration is possible, but not clear in the literature.

CONCLUSIONS

Sleep duration, especially short duration, is associated with high blood pressure in adolescents. Such evidence draws attention to implications on cardiovascular health in this age group.

The relationship between sleep and autonomic health

Objective: To examine the relationship between sleep and resting autonomic nervous system (ANS) functioning in college students. Participants: Participants were 141 undergraduate students (52 males) recruited from a large southeastern university during September-October 2017. Methods: Participants completed self-report inventories (demographic and sleep characteristics). Resting state skin conductance (SC) and heart rate variability (HRV) were measured in a laboratory setting for ANS functioning. Results: SC was positively associated with sleep quality (p = 0.027), sleep latency (p = 0.040), and use of sleep medication (p < 0.001). Analyses yielded a negative association between the standard deviation of the normal-normal interval of heart beats (SDNN) and the self-reported amount of time to fall asleep each night (p = 0.041). Sleep efficiency was negatively correlated with low frequency HRV (p = 0.002). Conclusions: Sleep components are associated with resting ANS activity, and targeted interventions focused on improved ANS functioning may benefit sleep quality in college students.

Sleep Quality as a Mediator of the Relationship Between Cyber Victimization and Depression

PURPOSE

Cyber victimization is a national mental health concern, especially among adolescents who are digital natives. The current study examined sleep quality as a mediator of the association between cyber victimization and depressive symptoms among adolescents.

DESIGN AND METHOD

A prospective study design was utilized with a community sample of adolescents (N = 801; 57% female; mean age = 14.45, SD = .85) from the eastern United States. Participants completed (a) the Pittsburgh Sleep Quality Index; (b) the Cyber Victimization Scale; and (c) the Center for Epidemiologic Studies Depression Scale Revised via online surveys at baseline and 6-month follow-up. The inter-relationship between variables was analyzed by Hayes' mediation approach.

FINDINGS

Cyber victimization was not directly associated with having depressive symptoms 6 months later when controlling for adolescents' poor sleep quality, sex, and age (direct effect [c'] = .012, t(676) = 1.12, p < .05, confidence interval [CI] -.008, .036). The mediation analysis indicated a significant indirect effect of poor sleep quality on the relationship between cyber victimization and depressive symptoms (ab = .005, bootstrapped standard error [SE] = .003, bootstrapped CI .001, .011; a is the effect of cyber victimization on poor sleep quality; b is the effect of poor sleep quality on depressive symptoms). Specifically, adolescents' cyber victimization led to poor sleep quality (a = .039, SE = .041, p < .05), which also led to increased depressive symptoms (b = .116, SE = .019, p < .001), after controlling for depressive symptoms at baseline, sex, and age. The indirect effect of cyber victimization on depressive symptoms was estimated through poor sleep quality (a*b = .039(.116) = .0045).

CONCLUSIONS

The findings suggest that poor sleep quality may be a mechanism through which cyber bullying is related prospectively to depressive symptoms. Interventions for cyber-victimized adolescents should include assessment of sleep quality and incorporate sleep hygiene education.

CLINICAL RELEVANCE

Adolescents should be screened for cyber victimization and sleep quality. Moreover, promotion of sleep hygiene among cyber-victimized adolescents may help to reduce depression.

Sleep and obesity among children: A systematic review of multiple sleep dimensions

The objectives were to systematically investigate the multiple dimensions of sleep and their association with overweight or obesity among primary school-aged children. CINHAL, PsycINFO, SPORTDiscus, Medline, Cochrane, Embase, and PubMed databases were searched for papers reporting on an association between children's sleep and weight status. Studies on clinical populations, published in languages other than English, without objectively measured weight status, or where weight status was reported outside the outlined age bracket (5-13 years) were excluded. A total of 34  248 citations were extracted from our systematic search protocol, of which 112 were included for detailed review. Compared with sleep duration, of which 86/103 articles found a significant inverse association between sleep duration and measured weight status, few studies examined other dimensions of sleep, such as quality, efficiency and bed/wake times, and relationship with weight status. Where studies existed, variation in defining and measurement of these dimensions restricted comparison and potentially influenced discrepancies across results. Overall, the findings of this review warrant the need for further research of the outlined dimensions of sleep. Future research would benefit from clarity on definitions across the different dimensions, along with the use of valid and reliable tools.

Association of Sleep Duration and Blood Pressure in Adolescents: A Multicenter Study

BACKGROUND

Evidence suggests that sleep duration is related to blood pressure (BP), but the findings are still inconsistent for adolescents.

OBJECTIVE

To analyze the association between sleep duration and BP in Brazilian adolescents between 12 and 17 years of age.

METHODS

This study is part of the Study of Cardiovascular Risk in Adolescents (ERICA), a multicenter, school-based, cross-sectional study in 273 municipalities in Brazil. The sample consisted of 65,643 adolescents. Sleep duration was measured by a subjective method, and BP was measured by the oscillometric method. Multiple linear regression analyses were performed to evaluate the association between sleep duration and BP.

RESULTS

The mean sleep duration was 8.14 hours (± 1.40), with significant difference between the groups according to BP levels (P < 0.0001). The mean systolic and diastolic BP were 110.59 (± 11.87) and 65.85 (± 7.94) mm Hg, respectively, in the group of adolescents. Sleep duration was significantly associated with BP. Each increase 1 hour in sleep was associated with BP reduction in both sexes combined (P < 0.0001). Considering the effects of covariates, each increase 1 hour in sleep was associated with systolic BP (SBP) reduction among boys (P = 0.004) and SBP elevation among girls (P = 0.009), after full adjustment.

CONCLUSION

The results suggest that each increase in sleep duration was associated with SBP elevation among girls. Such findings may have important implications for cardiovascular health in adolescence.

Association between sleep duration and hypertension of migrant workers in China: a national cross-sectional surveillance study

OBJECTIVES

To examine the relationship between sleep duration and hypertension of migrant workers aged 18-59 years in China.

DESIGN

Population-based cross-sectional study using a complex survey sampling design.

PARTICIPANTS

There were 43 655 subjects in our analysis, after excluding people with missing information for key exposure and outcome variables and abnormal values for sleep duration (≤2 or ≥17 hours).

PRIMARY OUTCOME MEASURE

Hypertension was defined as systolic blood pressure (BP) ≥140 mm Hg and/or diastolic BP ≥90 mm Hg, or self-reported history of hypertension diagnosis in hospitals at the township (community) level or above and use of hypertensive medicine in the last 2 weeks.

RESULTS

Of 43 655 subjects, 15.6% (95% CI 15.1% to 16.1%) of migrant workers had hypertension. The prevalence of hypertension decreased with the increased sleep duration, both in males and females. Logistic regression models, using 7-8 hours sleep/day as the reference, showed a greater odds for hypertension among men and women who reported <6 hours of sleep after adjusting for sociodemographic characteristics, behavioural risk factors, body mass index, diabetes, stroke and myocardial infarction (men: OR 1.26; 95% CI 1.03 to 1.54, women: OR 1.55; 95% CI 1.13 to 2.06, p_interaction=0.096). Further stratified by age and migration time, it revealed that among adults less than 45 years old, those sleeping 9 or more hours had adjusted odds for hypertension of 0.82 (95% CI 0.72 to 0.93, p_interaction=0.020),while there was no evidence of an association between sleep duration and hypertension among adults aged 45-59 years. Among adults whose migration time was less than 4.5 years, those sleeping 9 or more hours had adjusted odds for hypertension of 0.80 (95% CI 0.68 to 0.94, p_interaction=0.097).

CONCLUSION

The association between sleep duration and hypertension varies by age. Short sleep duration (<6 hours) is associated with an increased prevalence of hypertension in both genders.

Sleep characteristics and health-related quality of life in 9- to 11-year-old children from 12 countries

INTRODUCTION

Previous studies have linked short sleep duration, poor sleep quality, and late sleep timing with lower health-related quality of life (HRQoL) in children. However, almost all studies relied solely on self-reported sleep information, and most studies were conducted in high-income countries. To address these gaps, we studied both device-measured and self-reported sleep characteristics in relation to HRQoL in a sample of children from 12 countries that vary widely in terms of economic and human development.

METHODS

The study sample included 6,626 children aged 9-11 years from Australia, Brazil, Canada, China, Colombia, Finland, India, Kenya, Portugal, South Africa, the United Kingdom, and the United States. Waist-worn actigraphy was used to measure total sleep time, bedtime, wake-up time, and sleep efficiency on both weekdays and weekends. Children also reported ratings of sleep quantity and quality. HRQoL was measured by the KIDSCREEN-10 survey. Multilevel regression models were used to determine the relationships between sleep characteristics and HRQoL.

RESULTS

Results showed considerable variation in sleep characteristics, particularly duration and timing, across study sites. Overall, we found no association between device-measured total sleep time, sleep timing or sleep efficiency, and HRQoL. In contrast, self-reported ratings of poor sleep quantity and quality were associated with HRQoL.

CONCLUSIONS

Self-reported, rather than device-based, measures of sleep are related to HRQoL in children. The discrepancy related to sleep assessment methods highlights the importance of considering both device-measured and self-reported measures of sleep in understanding its health effects.

Sleep, Diet, and Cardiometabolic Health Investigations: a Systematic Review of Analytic Strategies

PURPOSE OF REVIEW

Poor sleep is a risk factor for cardiometabolic morbidity. The relationship of sleep and cardiometabolic health could be confounded, mediated, or modified by diet, yet the incorporation of diet in sleep-cardiometabolic health studies is inconsistent. This rapid systematic literature review evaluates the conceptualization of diet as a confounder, mediator, or effect modifier within sleep-cardiometabolic health investigations, and the statistical approaches utilized.

RECENT FINDINGS

Of 4692 studies identified, 60 were retained (28 adult, 32 pediatric). Most studies included diet patterns, quality, or energy intake as confounders, while a few examined these dietary variables as mediators or effect modifiers. There was some evidence, mostly in pediatric studies, that inclusion of diet altered sleep-cardiometabolic health associations. Diet plays a diverse role within sleep-cardiometabolic health associations. Investigators should carefully consider the conceptualization of diet variables in these relationships and utilize contemporary statistical approaches when applicable.

Relationship between sleep duration and hypertension in northeast China: a cross-sectional study

OBJECTIVES

Previous studies have reported that sleep duration might increase the risk of hypertension. However, the results have been conflicting. We investigated whether sleep duration is independently associated with hypertension. We aimed to assess the relationship between sleep duration and hypertension in a population-based cross-sectional study.

METHODS

In this study we used multistage stratified cluster sampling. A total of 19 407 adults aged 18-79 years were enrolled in the study. The participants were divided into three groups (<7 hours/day, 7-8 hours/day and >8 hours/day) according to self-reported sleep duration. Hypertension was defined as systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg or the use of anti-hypertensive medications. Univariate and multivariate logistic regressions were performed to determine the association between hypertension and sleep duration adjusted for sociodemographic, body mass index, and lifestyle covariates.

RESULTS

The overall prevalence of hypertension was 32.6%. Among participants aged 18-44 years, individuals sleeping less than 7 hours per day had a higher risk of hypertension (OR=1.24, 95% CI: 1.05 to 1.46), compared with those who slept 7-8 hours per day. There were no significant associations between sleep duration and hypertension in the total sample, among middle-aged adults (45-59 years) or older adults (60-79 years).

CONCLUSIONS

Our study demonstrates that short sleep duration was significantly associated with hypertension among people aged 18-44 years in northeast China.

An epidemiologic study of self-reported sleep problems in a large sample of adolescent earthquake survivors: The effects of age, gender, exposure, and psychopathology

BACKGROUND

This study investigated the prevalence of sleep problems and their associated risk factors in child and adolescent survivors three years after the 2013 Ya'an earthquake.

METHODS

A total of 6132 adolescent survivors aged 9-18 years were invited to complete the Pittsburgh Sleep Quality Index, Children's Revised Impact of Event Scale-13, Short Mood and Feelings Questionnaire, and Screen for Child Anxiety-Related Emotional Disorders. Logistic analysis was used to identify possible relationships of sleep disturbance scores with earthquake exposures, mental health and demographic characteristics.

RESULTS

More than a quarter of the sample showed sleep problems of some kind, with 23.1% sleeping fewer than 7 h per night, 32.5% having difficulty falling asleep, 24.2% having difficulty remaining asleep, 25.3% having poor sleep quality, 17.4% having nightmares and 44.6% having difficulty functioning during daytime hours. Older participants were at a significantly higher risk of sleep issues than younger children (OR 2.89), and the subjects had significantly elevated risks of probable anxiety (OR 3.47), probable depression (OR 2.45), and probable posttraumatic stress disorder (OR 1.89). Other risk factors for sleep problems were earthquake exposure variables, including being injured (OR 1.42), having a parent injured (OR 1.27), witnessing death (OR 1.32) or feeling extremely scared (OR 1.22) in the Ya'an earthquake.

CONCLUSIONS

Sleep disturbances are common in adolescent earthquake survivors, and they are associated with age, gender, psychiatric symptoms and factors related to earthquake exposure. These results highlight the importance of development- and gender-specific interventions to prevent sleep disturbances after a major earthquake.

Correlates of elevated blood pressure in healthy children: a systematic review

The prevalence of hypertension in children is increasing globally. Addressing this will require a robust understanding of associated risk factors. To this end, we conducted a systematic review to identify correlates of elevated blood pressure (BP) in children. Literature searches were conducted using pre-defined search terms from three academic databases. The abstract and full text of identified studies were screened for eligibility by two independent reviewers. A total of 100 studies were included in this systematic review. An assessment tool was first used to assess study quality; a narrative synthesis was then performed. We found a broad range of physiological, social and behavioural factors associated with elevated BP in children. The most common correlate observed was adiposity, suggesting that childhood obesity may be implicated in the increased prevalence of hypertension observed in children. However, the broad range of other factors identified underscores the multi-factorial aetiology of hypertension. Data from a broad range of studies showed that the correlates of hypertension in children are multi-factorial. Therefore, approaches aimed at preventing hypertension must in turn be multi-factorial to ensure that the burden of hypertension in childhood is addressed.

Association of sleep quality with sociodemographic factors and lifestyle in adolescents from southern Brazil

BACKGROUND

Good sleep quality is an essential component for growth, development, and physical and mental health of the individual, in addition to being a positive indicator of health and well-being. The objective of this study was to estimate the prevalence of poor sleep quality and to identify the association of poor sleep quality with sociodemographic factors, lifestyle, weight status, and associated aerobic fitness in adolescents.

METHODS

This study included 1110 students aged 14-19 years from city of São José/SC, Brazil. Sleep quality of the subjects was assessed using a questionnaire and classified as adequate and low. Independent variables were gender, age, monthly household income, maternal education, school shift, global physical activity, proper diet, screen time, sleeping hours of full week, sleeping hours of weekdays, sleeping hours of weekends, weight status, and aerobic fitness. Binary logistic regression was used to estimate odds ratios and confidence intervals of 95%.

RESULTS

Prevalence of poor sleep quality was 60.4%. More likely to have poor sleep quality were identified in female students (OR 1.68, 95% CI 1.11-2.55), whose mothers had higher levels of education (OR 1.44, 95% CI 1.20-1.73) and low aerobic fitness (OR 1.80, 95% CI 1.02-3.19).

CONCLUSION

Adolescents who were most likely to report poor sleep quality were female, those whose mothers had a higher educational level and had low aerobic fitness. Students with sedentary risk behavior were less likely of reporting poor sleep quality.

A Systematic Review of Sleep, Hypertension, and Cardiovascular Risk in Children and Adolescents

PURPOSE OF REVIEW

Many of the risk factors for heart disease have recently been shown to develop during childhood such as left ventricular hypertrophy and fibrous plaque lesions. As risk for cardiovascular disease in children and adolescents has risen, sleep duration has decreased, and inadequate sleep in children and adolescents has been found to be associated with cardiovascular disease risk. The aims of this manuscript are to provide an updated systematic review of the literature assessing sleep, hypertension, and cardiovascular risk and evaluate the strength of the evidence based on the available research.

RECENT FINDINGS

A systematic review was conducted using six databases from January 1, 2015 through March 9, 2018. We sought studies which looked at the relationship between sleep duration, sleep timing, or sleep quality and outcome variables of hypertension, inflammation, obesity, glucose or insulin, and lipids in children and adolescents. We found 24 studies which met our criteria. Nine studies included hypertension as an outcome variable; fifteen included obesity; thirteen included glucose or insulin; eight included lipids; and three included measures of inflammation. The existing literature on sleep and cardiovascular disease in children and adolescents is limited and relatively weak. Only one RCT was identified, and the overwhelming majority of studies had a high risk of bias. The strongest evidence of an association with sleep is with obesity, hypertension, and insulin sensitivity. Further research using more standardized methods and objective measures is needed to determine if a causal relationship truly exists between sleep and cardiovascular risk.

Differences in self-reported weekend catch up sleep between children and adolescents with and without primary hypertension

Background

The data on the association of sleep duration and blood pressure in the pediatric age group have been mixed and most studies have focused on weekday sleep duration. The purpose of this study was to compare the weekday and weekend sleep patterns between children and adolescents with newly diagnosed primary hypertension and a normotensive control group.

Methods

Children and adolescents from a pediatric nephrology clinic, aged 6-18 years with newly diagnosed primary hypertension were compared to an age and sex matched normotensive control group from a general pediatric clinic. The questions about bed time and getting out of bed times from the Pediatric Sleep Questionnaire (PSQ) were used to obtain weekday and weekend bed time, getting out of bed time and sleep duration. The Pediatric Daytime Sleepiness Scale (PDSS) was used to assess subjective sleepiness.

Results

In both groups of 60 subjects each, weekday total sleep time was similar. Subjects in both groups went to bed later and woke up later on the weekends. However, in the hypertensive group, weekend getting out of the bed time was earlier (8:52 AM ±93 min vs. 9:36 AM ±88 min, p = 0.013) and weekend catchup sleep was about 40 min less (62.8 ± 85.5 vs. 102.7 ± 84.9, p = 0.035). Hypertensive children perceived less subjective sleepiness (PDSS scores 8.28 ± 4.88 vs. 10.63 ± 5.41, p = 0.007). The p values were calculated after adjusting for body mass index (BMI), race, daytime nap, caffeine use, sleep related breathing disorder (SRBD) scale and periodic limb movement of sleep (PLMS) scale subcomponents of the PSQ.

Conclusions

Hypertensive children obtained less weekend catch up sleep and reported less subjective sleepiness compared to the control group. More weekend sleep may potentially mitigate the effect of weekday sleep deprivation on blood pressure.

The Relationship Between Blood Pressure and Sleep Duration in Turkish Children: A Cross-Sectional Study

OBJECTIVE

As in adults, hypertension is also an important risk factor for cardiovascular disease in children. We aimed to evaluate the effect of sleep duration on blood pressure in normal weight Turkish children aged between 11-17 years.

METHODS

This cross-sectional study was conducted in the primary and secondary schools of the two central and ten outlying districts of Kayseri, Turkey. Subjects were 2860 children and adolescents (1385 boys, 1475 girls). Systolic and diastolic blood pressures were measured according to the recommendations of the Fourth Report of the National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents. Sleep duration was classified as follows: ≤8 hours, 8.1-8.9 hours, 9.0-9.9 hours or ≥10 hours.

RESULTS

For short sleeper boys and girls (participants with a sleep duration ≤8 h) the prevalence of prehypertension and hypertension was 35.0% and 30.8%, respectively. In univariate binary logistic regression analyses (age-adjusted), each unit increment in sleep duration (hours) in boys and girls, decreased the prehypertension and hypertension risk by 0.89 [odds ratio (OR)] [confidance interval (CI); 0.82-0.98] and 0.88 (OR) (CI; 0.81-0.97), respectively (p<0.05). In multiple binary logistic regression analyses [age- and body mass index (BMI)-adjusted] the location of the school and sleep duration categories were shown to be the most important factors for prehypertension and hypertension in both genders, while household income was the most important factor, only in boys.

CONCLUSIONS

A sleep duration ≤8 h is an independent risk factor for prehypertension and hypertension in Turkish children aged 11-17 years.

Sugar-sweetened beverages and school students' hypertension in urban areas of Nanjing, China

Literature showed that sugar-sweetened beverages (SSBs) could increase the risk of developing hypertension in school students, but there is no reported evidence from China yet, so this study aims to investigate the association of the SSBs consumption and school students' hypertension in urban areas of Nanjing, China. A cross-sectional survey was conducted among primary and junior high school students selected from 32 primary schools and 16 junior high schools using a multi-stage random sampling method, with a total number of 10,091 participants involved. The mean age of Grade 4 is 9.04 ± 0.38, while the mean age of Grade 7 is 12.03 ± 0.41. Blood pressure was measured and SSBs consumption was reported using a validated questionnaire. The overall prevalence of hypertension was 4.5% among the participants. After adjustment for school, parental education, physical activity, diet intake including meat and snacks, participants who had an experience of SSBs intake were at a higher risk of developing hypertension (odds ratio (OR) = 1.40, 95% confidence interval (CI) = 1.15, 1.70) compared with those who had no experience of SSBs intake. A significant association between the consumption of SSBs and hypertension was observed among the students who were at a healthy weight (OR = 1.78, 95% CI = 1.20, 2.65), as well as who were overweight or obese (OR = 1.28, 95% CI = 1.01, 1.61). SSBs may play a contributing role in developing childhood hypertension in this population in China, which is of important implications for future population-based childhood hypertension intervention in China and other countries.

Systematic review of the relationships between sleep duration and health indicators in school-aged children and youth

The objective of this systematic review was to examine the relationships between objectively and subjectively measured sleep duration and various health indicators in children and youth aged 5-17 years. Online databases were searched in January 2015 with no date or study design limits. Included studies were peer-reviewed and met the a priori-determined population (apparently healthy children and youth aged 5-17 years), intervention/exposure/comparator (various sleep durations), and outcome (adiposity, emotional regulation, cognition/academic achievement, quality of life/well-being, harms/injuries, and cardiometabolic biomarkers) criteria. Because of high levels of heterogeneity across studies, narrative syntheses were employed. A total of 141 articles (110 unique samples), including 592 215 unique participants from 40 different countries, met inclusion criteria. Overall, longer sleep duration was associated with lower adiposity indicators, better emotional regulation, better academic achievement, and better quality of life/well-being. The evidence was mixed and/or limited for the association between sleep duration and cognition, harms/injuries, and cardiometabolic biomarkers. The quality of evidence ranged from very low to high across study designs and health indicators. In conclusion, we confirmed previous investigations showing that shorter sleep duration is associated with adverse physical and mental health outcomes. However, the available evidence relies heavily on cross-sectional studies using self-reported sleep. To better inform contemporary sleep recommendations, there is a need for sleep restriction/extension interventions that examine the changes in different outcome measures against various amounts of objectively measured sleep to have a better sense of dose-response relationships.

Sleep in Adolescents and Young Adults with Type 1 Diabetes: Associations with Diabetes Management and Glycemic Control

OBJECTIVE

To describe sleep in adolescents and young adults with type 1 diabetes and explore the association between sleep disturbances, diabetes management and glycemic control.

METHODS

Adolescents with type 1 diabetes (n = 159, mean age = 16.4, 43% female, 69% white, mean A1C = 9.3%) completed the Pittsburgh Sleep Quality Index to assess sleep quantity and quality and sleep disturbances. Frequency of blood glucose monitoring (meter downloads) was used as a measure of diabetes management.

RESULTS

Average sleep duration was 7.4 hours, below the recommended duration for this age. Adolescents using insulin pumps reported fewer sleep disturbances and longer sleep duration than those on injections, and older adolescents reported less sleep than younger adolescents. Poorer sleep duration was related to poorer diabetes management and better self-reported sleep quality was associated with better glycemic control for males but not for females.

CONCLUSIONS

Assessing for and treating sleep disturbances in adolescents may improve diabetes management.

Relationships between Sleep Behaviors and Unintentional Injury in Southern Chinese School-Aged Children: A Population-Based Study

The purpose of this study is to explore the relationships between sleep behaviors and injury occurrence among Chinese school-aged children. Data were collected with self-administered questionnaires of a cross-sectional survey which covered the school-aged children from southeastern Chinese urban and rural areas in April 2010. Information was collected on unintentional injury in the past year, sleep duration, napping and daytime fatigue, sleeping pill use, and social-demographic variables. Multivariable logistic regression analyses, controlling for confounding factors, were conducted to assess sleep-related variables that were associated with injuries. Students who slept for less than 8 h had a 30% increased risk of injury (OR: 1.30; 95%CI: 1.01-1.69) compared with those who slept for 8-9 h. Lack of napping, snoring and use of sleeping pills were significantly associated with injury. Among different genders, the slight difference in sleep behaviors predicted the occurrence of injury. Rural children displayed more sleep behaviors associated with injury than urban children. The sleep behaviors of primary school students were more negatively correlated with injury occurrence than junior/senior high school children. Consideration should be given to the prevention of problematic sleep behaviors as a potential risk factor in order to decrease injury rates and promote the health of school-aged children.

Advancing a biopsychosocial and contextual model of sleep in adolescence: a review and introduction to the special issue

Sleep problems in adolescence have been identified as an international public health issue. Over the past few decades, notable advances have been made in our understanding of the patterns and consequences of sleep in adolescence. Despite these important gains, there is much about the role of sleep in adolescence that remains to be understood. This Special Issue brings together studies that examine sleep as it specifically pertains to adolescent development and adjustment. In this introductory article, we argue for the importance of grounding the study of sleep and adolescence in developmental science and a developmental psychopathology framework. First, a review of the literature is used to outline a biopsychosocial and contextual model of sleep in adolescence. Second, attention-deficit/hyperactivity disorder (ADHD) is used as an exemplar of the proposed model given the pervasiveness of sleep problems among youth with ADHD and the likelihood that sleep problems and ADHD symptoms are interconnected in complex ways. Finally, a brief introduction to the empirical articles included in the Special Issue is provided, with particular attention given to how these articles fit within the proposed biopsychosocial and contextual model. Along with the framework proposed in this article, the studies included in this Special Issue advance the current literature and point to critical directions for future research.