Weekend Bedtimes Research Articles

Socioeconomic factors, sleep timing and duration, and amygdala resting-state functional connectivity in children.

Reduced sleep health has been consistently linked with increased negative emotion in children. While sleep characteristics have been associated with neural function in adults and adolescents, much less is known about these associations in children while considering socioeconomic context. In this study, we examined the associations among socioeconomic factors, sleep duration and timing, and resting-state functional connectivity (rsFC) of the amygdala in children. Participants were typically-developing 5- to 9-year-olds from socioeconomically diverse families (61% female; N = 94). Parents reported on children's weekday and weekend bedtimes and wake-up times, which were used to compute sleep duration and midpoint. Analyses focused on amygdala-anterior cingulate cortex (ACC) connectivity followed by amygdala-whole brain connectivity. Lower family income-to-needs ratio and parental education were significantly associated with later weekday and weekend sleep timing and shorter weekday sleep duration. Shorter weekday sleep duration was associated with decreased amygdala-ACC and amygdala-insula connectivity. Later weekend sleep midpoint was associated with decreased amygdala-paracingulate cortex and amygdala-postcentral gyrus connectivity. Socioeconomic factors were indirectly associated with connectivity in these circuits via sleep duration and timing. These results suggest that socioeconomic disadvantage may interfere with both sleep duration and timing, in turn possibly altering amygdala connectivity in emotion processing and regulation circuits in children. Effective strategies supporting family economic conditions may have benefits for sleep health and brain development in children.

Association between COVID-19 lockdown and sleep behaviors in Korean adolescents.

To find the effect of coronavirus disease 2019 (COVID-19)-related sleep behavior changes using school-based self-reported data from a nationally representative Korean adolescent population. We analyzed web-based self-reported data from the Korean Youth Risk Behavior Web-based Survey in 98,126 participants (51,651 in 2019 [before the COVID-19 pandemic]; 46,475 in 2020 [during COVID-19 pandemic] 12 through 18 years old were included in this study. Self-report questionnaires were used to assess socioeconomic status, health behaviors, psychological factors, and sleep patterns. During the COVID-19 pandemic, Korean adolescents had a later weekend bedtime (≥1:00 am: 68.2% vs 71.5%, P < .001) and late weekend wake time (≤7:00 am: 13.3% vs 10.7%, P < .001) compared to before COVID-19 pandemic. Average sleep duration (434.7 ± 102.6 vs 428.2 ± 100.4 minutes; P < .001) was significantly lower during the COVID-19 pandemic and weekend catch-up sleep >2 hours (42.1% vs 43.7%; P < .001), late chronotype (17.1% vs 22.9%, P < .001) were significantly higher during COVID-19 pandemic. After adjusting for multiple confounding variables, short sleep duration (≦5 hours, odds ratio [OR] 1.14; 95% confidence interval [CI] 1.10-1.19), 6 hours, OR 1.07; 95% CI 1.03-1.12), long weekend catch-up sleep (OR, 1.08; 95% CI, 1.06-1.11) and late chronotype (OR, 1.43; 95% CI, 1.38-1.47) were significantly associated with COVID-19 pandemic. The COVID-19 pandemic was associated with changes in sleep behavior among Korean adolescents, resulting in later bed and wake-up times, increased weekend catch-up sleep, and a shift of chronotype toward eveningness.

0754 Sleep Ecology in Low-Income Mexican American Toddlers

Abstract Introduction Healthy sleep is critical for child development, yet disparities exist, with Latino children disproportionately affected by deficient sleep. Most of what is known about sleep ecology and interventions to improve sleep in young children is based on studies of primarily White, non-Latino, and economically-advantaged families. To ensure the effectiveness of interventions, it is important to understand the contribution of socioecological factors on sleep among toddlers in low-income Mexican American families. Methods This study employed in-depth interviews with a purposeful sample of low-income Mexican American Spanish-speaking (n=10) and English-speaking mothers (n=10) of toddlers (18-34 months old). Interviews focused on daily sleep routines, perceptions of toddler sleep behaviors, and environmental contributors. Transcripts were coded by two investigators and analyzed using a content analytic approach. Results For sleep-related parenting practices, 70% of mothers reported late child bedtimes (≥9:00 pm), 75% reported room/bed sharing, and almost a third of children fell asleep at bedtime with a bottle or cup. Maternal beliefs about child sleep included concerns that child crying during the night might disturb neighbors or wake siblings, and child sleep quality improved when the child is not hungry. Contextual factors impacting sleep included schedules, neighbors, and siblings. Specifically, later weekday bedtimes were attributed to maternal (but not paternal) work schedules, while wake times were often a result of a sibling’s school schedule. Weekend bedtimes were commonly reported to be delayed for toddlers due to families watching movies. Noisy neighbors, in particular upstairs neighbors, were identified as disrupting children’s sleep. Siblings were identified as both facilitating sleep (e.g., helping with routines) and disrupting sleep (e.g., distracting child at nap time). Conclusion Findings provide insights on socioecological factors and parental beliefs about sleep ecology in low-income Mexican American toddlers that have implications for the design of interventions to improve child sleep. For example, commonly used behavioral sleep interventions have children sleeping in their own room, or require some crying during the night. However, these approaches may not be a good fit or feasible for this population. To address sleep health disparities, further work is needed to understand socioecological factors that require inclusive adaptations to pediatric sleep interventions. Support (if any) R01HL163859

Examining the interactive association of family- and neighborhood-level socio-economic characteristics on children's sleep beyond the associations of residency and neighborhood violence

ObjectiveTo examine the interactive association of neighborhood and family socio-economic characteristics (SEC) on children's sleep. DesignSecondary data analyses were completed on the 2014 Ontario Child Health Study, a cross-sectional sample of 10,802 children aged 4-17. ParticipantsChildren (aged 4-11, 50% male; N = 6264) with available sleep outcome data. MethodsMultilevel modeling was used to assess the interactive relationship between family- and neighborhood-level poverty in relation to child sleep outcomes (problems falling asleep, problems staying asleep, weekday and weekend time in bed), above the associations of variables known to be related to sleep at the child (ie, child age, sex, internalizing problems, externalizing problems, chronic illness), family (ie, negative parenting behaviors, family structure, parent mental health, years lived in neighborhood, parent education level), and neighborhood levels (ie, neighborhood size, antisocial behavior). ResultsNeighborhood poverty (p < .01, ß = -0.001, 95% confidence interval [-0.007, -0.002]) was significantly related to shorter weekday time in bed and the interactive association of family and neighborhood poverty was significantly related to weekend time in bed (p < .05, ß = 0.012, 95% confidence interval [0.004, 0.021]). Children living in low poverty neighborhoods with families of higher SEC backgrounds, and children living in high poverty neighborhoods with families of lower SEC backgrounds had the shortest weekend time in bed (9.7 hours). ConclusionsThere is a compound relationship of family and neighborhood poverty on children's sleep above and beyond family- and child-level risk factors.

Sex and racial/ethnic disparities in sleep duration and timing on weekdays and weekends across lifespan in the US population: Sex and racial/ethnic disparities in sleep

BackgroundSleep affects health. Sleep habits differ between population subgroups and may also differ between weekdays and weekends; however, these patterns are rarely described at the population level. PurposeTo investigate age and racial/ethnic differences in sleep duration and timing between weekdays (workdays) and weekends (non-workdays). MethodsA cross-sectional analysis of the US nationally representative data from the National Health and Nutrition Examination Survey among adolescents (16-19 years) and adults (≥20 years). ResultsData on 10069 individuals were analyzed (51% female), including 959 adolescents and 9110 adults. The hours per night of sleep were shorter during weekdays (7.6, 95%CI: 7.6 to 7.7) than on weekends (8.3, 95% CI: 8.3 to 8.2). Females slept shorter hours than males on weekdays (7.7 [95%CI, 7.7 to 7.8] vs. 7.5 [95%CI, 7.4 to 7.5]) and on weekends (8.5, [95%CI, 8.4 to 8.5] vs. 8.2 [95% CI, 8.1 to 8.2]). Non-Hispanic blacks (7.4, 95% CI: 7.4 to 7.5) reported the shortest weekdays sleep. With respect to sleep timing, comparing to weekdays, males reported 30-min delayed weekends bedtime (23:30 [IQR, 22:30-00:30] vs. 23:00 [IQR, 22:00-00:00]), whereas both sexes reported 1.5-hour delayed weekends wake-up time (male: 07:30 [IQR, 06:30-09:00] vs. 06:00 [IQR, 05:30-07:30]; female: 08:00 [IQR, 06:30-09:00] vs. 06:30 [IQR, 05:30-07:30]). The delayed weekend bedtime and wake-up times were observed in all racial/ethnic groups. ConclusionsIn the US population, sleep habits differed between weekdays and weekends. Shorter sleep hours and delayed sleep timing were noted and more apparent among racial/ethnic minorities of both sexes.

Association between bedtime at night and nonalcoholic fatty liver disease diagnosed by liver ultrasound transient elastography

ObjectiveWe aimed to explore the association between bedtime at night and nonalcoholic fatty liver disease (NAFLD) measured by liver ultrasound transient elastography (LUTE). MethodsA total of 4572 individuals were included. The diagnosis of NAFLD was based on the controlled attenuated parameter (CAP) score of LUTE. CAP score ≥ 263 dB/m and CAP score ≥ 285 dB/m were used as the criterions for the diagnosis of NAFLD. ResultsFor the weekday bedtime, a positive association was identified in CAP (263 dB/m) (OR, 1.04 [95 %CI, 0.99, 1.09]) and CAP (285 dB/m) (OR, 1.00 [95 %CI, 0.95, 1.05]). For the weekend bedtime, a positive relationship was found in CAP (263 dB/m) (OR, 1.05 [95 %CI, 1.00, 1.10]). The positive relationship still presented in CAP (285 dB/m) (OR, 1.05[95 %CI, 1.00, 1.10]). When NAFLD defined as CAP score ≥ 263 dB/m, the relationship between weekday bedtime and NAFLD was a straight line. For the weekend bedtime, the association was nonlinear. Before 22:00 o’clock, the association was positive (OR, 1.26 [95 %CI, 1.06, 1.50]), while between 22:00 and 1:00 o’clock, the relationship was negative (OR, 0.96 [95 %CI, 0.88, 1.05]) without a significant P value. After 1:00o’clock, the relationship was positive (OR, 1.26 [95 %CI, 1.02, 1.57]). ConclusionLater bedtime was positive associated with NAFLD.

Sleeping through a Lockdown: How Adolescents and Young Adults Struggle with Lifestyle and Sleep Habits Upheaval during a Pandemic

ABSTRACT Objectives The objective of the present study was to investigate the relationship between chronotype, lifestyle habits during the pandemic, and changes in sleep timing during the first wave of the COVID-19 pandemic in youth. Method An online survey of adolescents and young adults (N = 449) was conducted in June 2020. Multivariate hierarchical regressions assessed the contribution of chronotype and changes in lifestyle habits to sleep timing during the COVID-19 pandemic in two age groups (12 to 17 years old and 18 to 25 years old). Results Chronotype was a significant predictor of changes in sleep habits during the pandemic in both age groups. In adolescents, electronic device usage during the pandemic was a significant predictor of bedtimes and wake times on weekdays, and caffeine during the pandemic was a predictor of weekday wake times. The number of hours worked during the pandemic was a significant predictor of weekday wake times in both age groups. In young adults, cannabis consumption during the pandemic was a predictor of weekend bedtimes. A later chronotype, along with higher usage of electronic devices, fewer hours worked, as well as higher caffeine and cannabis consumption during the pandemic were associated with delayed sleep timing during the pandemic in youth. Conclusion These results highlight the importance of assessing lifestyle habits when exploring changes in sleep habits in youth.

Sleep during "lockdown" highlighted the need to rethink the concept of weekend catch-up sleep.

PurposeMany people believe in their ability to sleep for longer time on weekends to make up for sleep lost due to early wakeups on weekdays. This widely held belief was not supported by the simulations of rise- and bedtimes on weekdays and weekends with a sleep–wake regulating model. The simulations suggested the inability to extend sleep on any of two weekend nights and they predicted identical weekend sleep durations for weeks with relatively earlier and relatively later weekday risetimes. By April 2020, about half of the world’s population was under some form of “lockdown” due to the COVID-19 pandemic. This “lockdown” provided a new opportunity to demonstrate the predictive power of the sleep–wake regulating models. Therefore, the purpose of this report was to support the prediction of identity of weekend sleep durations after weeks with earlier and later weekday wakeups.MethodsWeekend and weekday rise- and bedtimes before and during “lockdown” for 31 samples were taken from recent journal publications. Time in bed on weekends and 12 other measures of sleep duration and timing were calculated and simulated.ResultsFor only one of 13 measures, weekend time in bed, statistical analysis did not yield a statistically significant difference between the estimates obtained before and during “lockdown”. The model-based simulations pointed to the 0.3-h delay of the sleep–wake cycle in response to the 1-h delay of weekday risetime during “lockdown”.ConclusionThe model-based prediction was confirmed, thus, highlighting again the necessity to rethink the concept of weekend catch-up sleep.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11325-021-02492-z.

Sleep trajectories from early adolescence to emerging adulthood: Evidence from a nine-year population-based study

IntroductionAdolescence to emerging adulthood is a developmental period when individuals experience substantial biological changes and social transitions. In East Asian societies, this period is also marked by high pressure around college entrance exams. However, little is known about how young people's sleep changes over time, or how it is impacted by social institutions in the cultural context. This study fills this gap in the literature by examining sleep trajectories from adolescence to emerging adulthood using a population-based, longitudinal sample from Taiwan. MethodsMultilevel models were applied to longitudinal data from the Taiwan Youth Project (N = 1,489) to estimate sleep trajectories from age 14 to 22 for total time in bed, bedtime, and wake-up time by gender and by educational pathway, controlling for family background. ResultsAnalysis revealed that Taiwanese youth sleep less as adolescents than as emerging adults. Gender differences exist in adolescents’ sleep trajectories but narrow after age 18. Differences in weekday and weekend time in bed vary by gender and change as individuals emerge into adulthood. Finally, college attendees and high school only attendees display differences in sleep that begin in high school and continue through college. ConclusionsThe findings provide evidence of developmental changes in sleep from adolescence to emerging adulthood and demonstrate that sleep trajectories are gendered and socially patterned. The study is also one of the first to examine the sleep trajectories of East Asian youth and, as such, sheds light on the role of educational and cultural context as an influential factor.

Longitudinal associations of sleep problems with alcohol and cannabis use from adolescence to emerging adulthood.

This study examined longitudinal associations of sleep problems with alcohol and cannabis use across six annual waves of data from adolescence to emerging adulthood. Participants were 3,265 youth from California (ages 16-22 across waves). At each wave, past-month alcohol use and cannabis use, mental health, and several dimensions of sleep health (i.e. social jetlag, bedtimes, time in bed, trouble sleeping) were assessed via questionnaire. Parallel process latent growth models examined the association between sleep and alcohol or cannabis use trajectories and the role of mental health in contributing to such trajectories. Smaller declines in social jetlag (r = 0.11, p = 0.04), increases in trouble sleeping (r = 0.18, p < 0.01), and later weekday (r = 0.16, p < 0.01) and weekend bedtimes (r = 0.25, p < 0.01) were associated with increases in likelihood of alcohol use over time. Declines in weekend TIB (r = -0.13, p = 0.03), as well as increases in weekday TIB (r = 0.11, p = 0.04) and later weekday (r = 0.18, p < 0.01) and weekend bedtime (r = 0.24, p < 0.01), were associated with increases in likelihood of cannabis use over time. Most associations remained significant after controlling for time-varying mental health symptoms. Trajectories of sleep health were associated with trajectories of alcohol and cannabis use during late adolescence to emerging adulthood. Improving sleep is an important target for intervention efforts to reduce the risk of substance use during this critical developmental transition.

Later bedtime is associated with angina pectoris in middle-aged and older adults: results from the Sleep Heart Health Study

ObjectivesSleep timing is related to several risk factors for angina pectoris (AP), such as obesity and diabetes. This study was designed to evaluate the relationship between sleep timing and AP, specifically whether later bedtime was associated with AP in middle-aged and older adults. MethodsThis community-based study was based on the Sleep Heart Health Study cohort and included 4710 participants (45.9% men, aged 63.3 ± 11.0 years). Lifestyle and epidemiological information were obtained from baseline records. Self-reported sleep measures provided information on bedtime and wake-up time of weekdays and weekends. Individuals were divided into three categories according to bedtime (≤22:00, 22:01–23:00, and >23:00). Odds ratios (OR) and 95% confidence intervals (CIs) of AP for bedtimes were estimated with multivariate logistic regression analysis. ResultsThe prevalence of AP was 44.2% and the distribution of weekday bedtimes ≤22:00, 22:01–23:00, and >23:00 were 36.6%, 47.5% and 46.0%, respectively. After adjusting for potential confounders, weekday bedtimes >23:00 (OR 1.34; 95% CI 1.13–1.60; P = 0.001) and 22:01–23:00 (OR 1.54; 95% CI 1.29–1.82; P < 0.001) were significantly associated with an increased risk of AP compared with the reference group (≤22:00). In addition, weekend bedtimes >23:00 (OR 1.44; 95% CI 1.20–1.73; P < 0.001) and 22:01–23:00 (OR 1.70; 95% CI 1.40–2.05; P < 0.001) increased the risk of AP. ConclusionsLater bedtimes on both weekdays and weekends were significantly associated with an increased prevalence of AP. Early bedtimes may help people decrease the risk of AP.

Vitamin D and sleep in children.

The impact of vitamin D on human health including sleep has been well described in adults. Its deficiency has been associated with multiple sleep disorders such as decrease in sleep duration, worsening of sleep quality, and even OSA. Such correlation is less evident in the pediatric population. In the current study, we examined the relationship between sleep architecture and vitamin D status in children referred to a sleep clinic. This was a retrospective-cohort study in a tertiary care children's hospital over a 1-year period. Children who underwent an in-laboratory overnight-polysomnogram and had a 25-hydroxy vitamin D level obtained within 120 days of the sleep study were included. Patients with OSA or central sleep apnea were excluded. Data from polysomnograms and Pediatric Sleep Questionnaires were collected and analyzed. A total of 39 patients (mean age, 6.6 years; 46% female) were included in the study. Twenty (51%) patients had vitamin D deficiency (25-hydroxy vitamin D level < 30 ng/mL). Children with vitamin D deficiency had less total sleep time (470.3 minutes ± 35.6 vs 420.3 minutes ± 61.7; P = .004) and poorer sleep efficiency (91.9% ± 5.6% vs 84.5% ± 9.5%; P = .015) compared with children with sufficient vitamin D. In addition, children with vitamin D deficiency had later weekday bedtimes (21:02 Pm ± 1:01 vs 20:19 Pm ± 0:55; P = .037) and later weekend bedtimes (21:42 Pm ± 0:59 vs 20:47 Pm ± 1:08; P = .016) than children with sufficient vitamin D, with a tendency for later wake time that did not reach statistical significance. The remainder of the polysomnogram findings and Pediatric Sleep Questionnaire data were not different between the 2 groups. Vitamin D deficiency in children was associated with objectively measured decreased sleep duration and poorer sleep efficiency. Furthermore, vitamin D deficiency was associated with delayed bedtimes, suggesting that vitamin D and circadian rhythm could be related. Future prospective studies in children would be helpful to learn if vitamin D deficiency leads to sleep disturbance or vice versa.

Association of Outdoor Artificial Light at Night With Mental Disorders and Sleep Patterns Among US Adolescents

Indoor nighttime light exposure influences sleep and circadian rhythms and is known to affect mood-associated brain circuits in animals. However, little is known about the association between levels of nighttime outdoor light and sleep and mental health in the population, especially among adolescents. To estimate associations of outdoor artificial light at night (ALAN) with sleep patterns and past-year mental disorder among US adolescents. This population-based, cross-sectional study of US adolescents used the National Comorbidity Survey-Adolescent Supplement, a nationally representative cross-sectional survey conducted from February 2001 through January 2004. A probability sample of adolescents aged 13 to 18 years was included. Analyses were conducted between February 2019 and April 2020. Levels of outdoor ALAN, measured by satellite, with means calculated within census block groups. ALAN values were transformed into units of radiance (nW/cm2/sr). Self-reported habitual sleep patterns (weeknight bedtime, weeknight sleep duration, weekend bedtime delay, and weekend oversleep) and past-year mood, anxiety, behavior, and substance use disorders, measured via an in-person structured diagnostic interview. Parent-reported information was included in behavior disorder diagnoses. Among 10 123 adolescents (4953 boys [51.3%]; mean [SE] age, 15.2 [0.06] years [weighted]; 6483 for behavior disorder outcomes), ALAN was positively associated with indicators of social disadvantage, such as racial/ethnic minority status (median [IQR] ALAN: white adolescents, 12.96 [30.51] nW/cm2/sr; Hispanic adolescents: 38.54 [47.84] nW/cm2/sr; non-Hispanic black adolescents: 37.39 [51.88] nW/cm2/sr; adolescents of other races/ethnicities: 30.94 [49.93] nW/cm2/sr; P < .001) and lower family income (median [IQR] ALAN by family income-to-poverty ratio ≤1.5: 26.76 [52.48] nW/cm2/sr; >6: 21.46 [34.38] nW/cm2/sr; P = .005). After adjustment for several sociodemographic characteristics, as well as area-level population density and socioeconomic status, this study found that higher ALAN levels were associated with later weeknight bedtime, and those in the lowest quartile of ALAN reported the longest weeknight sleep duration. Those in the highest quartile of ALAN went to bed 29 (95% CI, 15-43) minutes later and reported 11 (95% CI, 19-2) fewer minutes of sleep than those in the lowest quartile. ALAN was also positively associated with prevalence of past-year mood and anxiety disorder: each median absolute deviation increase in ALAN was associated with 1.07 (95% CI, 1.00-1.14) times the odds of mood disorder and 1.10 (95% CI, 1.05-1.16) times the odds of anxiety disorder. Further analyses revealed associations with bipolar disorder (odds ratio [OR], 1.19 [95% CI, 1.05-1.35]), specific phobias (OR, 1.18 [95% CI, 1.11-1.26]), and major depressive disorder or dysthymia (OR, 1.07 [95% CI, 1.00-1.15]). Among adolescent girls, differences in weeknight bedtime by ALAN (third and fourth quartiles vs first quartile) were greater with increasing years since menarche (F3, 8.15; P < .001). In this study, area-level outdoor ALAN was associated with less favorable sleep patterns and mood and anxiety disorder in adolescents. Future studies should elucidate whether interventions to reduce exposure to ALAN may positively affect mental and sleep health.

Frequency and Correlates of Sleep Debt in St. Petersburg

During weekdays, many of us fail meeting their physiologic sleep need. During weekends, however, when given additional sleep opportunity, homeostatic sleep pressure will typically lead to longer bedtimes, manifesting the cumulative sleep debt. This study aims at examining the prevalence and determinants of sleep debt, as indicated by the presence of ≥ 2 h weekend bedtime prolongation, in a general population. We studied 257 healthy subjects living in St. Petersburg, Russia. All participants indicated their habitual bedtimes during weekdays and weekends, and completed the Epworth Sleepiness Scale (ESS), Fatigue Severity Scale, Fatigue Impact Scale, Pittsburgh Sleep Quality Index, and Hospital Anxiety and Depression Scale. One-hundred-three participants (40%) exhibited a relevant sleep debt (≥ 2 h weekend–weekday difference in habitual bedtime). Compared to participants without sleep debt, the frequency of excessive daytime sleepiness (ESS score ≥ 11)—but not of fatigue, impaired sleep quality and mood disturbances—was higher in participants with sleep debt (21% vs. 10%, p = 0.01). Multiple regression analysis revealed younger age, higher ESS and lower body mass index as independent associates of sleep debt. Sleep debt appeared to be very common among healthy subjects, and independently associated with younger age, higher ESS scores and lower BMI. However, the presence of sleep debt did not have an impact on fatigue or mood, as measured by validated questionnaires.

0036 Inconsistent Bedtimes Associated with Unhealthier Body Size in Older Adults

Abstract Introduction A variety of sleep related variables have been shown to impact measures of health, including duration of sleep, consistency of sleep, quality of sleep, and sleep disorders. These can impact respiratory health, metabolic health, immune function, and more. Older adults have been shown to have different sleep schedules, with mostly consistent weeknight and weekend bedtimes and more opportunities to nap. The study investigated which aspects of sleep best predicted body size (averaged standardized body mass index and percent body fat indices). Methods A sample of 304 older adults (55+) participated in surveys and health measures in an urban area in the southeastern United States. Survey data collected were reports of sleep during the last month, including duration at night, nap duration, measures of quality, typical weeknight and weekend bedtime, and reports of possible sleep disorders. Physiological measures, including height, weight, BMI, body fat percentage, blood sugars, blood fats, and fitness tests were conducted. Sleep data were weighted ((5*weeknight+2*weekend)/7) across the week. A hierarchical multiple regression model was run with a standardized average of BMI and body fat percentage with multiple sleep variables as a predictor, controlling for age and socioeconomic status. Results After controlling for age and socioeconomic status (SES), symptoms of obstructive sleep apnea, night sleep duration, nap duration, difficulty initiating and maintaining sleep, sleep midpoint, duration inconsistencies and midpoint inconsistences were added to the regression. SES and duration inconsistencies were significant predictors, explaining 16% of the variance in body size. Conclusion Inconsistent bedtimes may be associated with larger body size. Encouraging older adults to have consistent sleep schedules could help preserve health as they age. This may also reduce rates of disorders like obstructive sleep apnea, which are associated with higher BMI, and help promote better overall sleep quality and health. However, these older adults reported fairly consistent sleep midpoint, limiting interpretation of this variable. Support Psychological Sciences department funding

0956 Vitamin D and Sleep in Children

Abstract Introduction The impact of vitamin D on human health including sleep has been well described in adults. Its deficiency has been associated with multiple sleep disorders such as decrease in sleep duration, worsening of sleep quality and even obstructive sleep apnea. Such correlation is less evident in pediatric population. In the current study, we examined the relationship between sleep architecture and vitamin D status in children referred to a sleep clinic. Methods Retrospective-cohort study in a tertiary care children’s hospital over a one-year period. Children who underwent an in-laboratory-overnight-polysomnogram and had a 25-hydroxy vitamin D level (25-OH-vitD) obtained within 120 days of the sleep study were included. Patients with obstructive or central sleep apnea were excluded. Data from polysomnograms (PSG) and Pediatric Sleep Questionnaires (PSQ) were collected and analyzed. Results A total of 39 patients were included in the study with mean age of 6.6 years and 46% females. Twenty (51%) patients had vitamin D deficiency (25-OH-vitD less than 30 ng/ml). Children with vitamin D deficiency had less total sleep time (470.3 minutes +/-35.6 vs 420.3 minutes +/-61.7, p=0.004) and poorer sleep efficiency (91.9 % +/-5.6 vs 84.5 % +/-9.5, p=0.015) compared to vitamin D sufficient children. In addition, vitamin D deficient children had later weekday bedtimes (21:02 +/- 1:01 vs 20:19 +/- 0:55, p=0.037) and later weekend bedtimes (21:42 +/- 0:59 vs 20:47 +/- 1:08, p=0.016) with tendency for later wake up time that did not reach statistical significance. The remainder of polysomnographic findings and PSQ data were not different between the two groups. Conclusion Vitamin D deficiency in children is associated with objectively measured decreased sleep duration and poorer sleep efficiency. Furthermore, vitamin D deficiency was associated with delayed bedtimes, suggesting that vitamin D may influence circadian rhythm. Future prospective studies in children would be helpful in validating the effect of vitamin D on sleep. Support None

Associations of sleep duration and social jetlag with cardiometabolic risk factors in the study of Latino youth

ObjectiveWe investigated associations of sleep duration and social jetlag with cardiometabolic outcomes. ParticipantsBoys and girls aged 8–16 years from the Hispanic Community Health Study/Study of Latino Youth. MeasurementsParticipants (n = 1,208) completed a clinical examination where anthropometric characteristics, health behaviors, and health history were measured. Sleep duration was calculated as the weighted average of self-reported weekday and weekend bedtimes and wake times and categorized into age-specific cutoffs for short vs. normal sleep. “Social jetlag” was defined as the absolute difference in the midpoint of the sleep period between weekdays and weekends, measured continuously and dichotomized (≥2 hours), with higher values indicating more displacement of sleep timing across the week. Regression models tested the associations between sleep measures (separately) and cardiometabolic outcomes (e.g., healthy eating index [0–100], physical activity-minutes per week, obesity, diabetes, hypertension) after adjustment for covariates. ResultsThe average sleep duration was 9.5 hours (95% confidence interval: 9.3, 9.6) and the mean social jetlag was 2.5 (2.4, 2.7) hours. Participants with social jetlag reported more physical activity (β = 34.8 [13.14], P < .01), had a higher healthy eating index (β = 1.77 [0.87], P < .05] and lower odds of being overweight [OR = 0.66, (95% confidence interval 0.44, 0.99)]. Short sleep duration was associated with less physical activity but did not relate to other cardiometabolic outcomes. ConclusionsSocial jetlag was associated with healthier behaviors and a lower odds of being overweight. Given these mixed findings, future research should further evaluate how to best characterize sleep timing differences in youth to identify health consequences.

Late bedtime and body mass index gain in indigenous Australian children in the longitudinal study of indigenous children.

To explore sleep patterns in indigenous Australian children and assess the role of sleep timing in longitudinal changes in body mass index (BMI). Latent profile analysis was conducted with the Australian Longitudinal Study of Indigenous Children (LSIC) cohort data (wave 5), to determine distinct patterns of bed and wake timing, taking account of weekday sleep duration, weekday and weekend bedtimes, and weekday wake times. Multilevel models with a random intercept were used to investigate the role of baseline sleep pattern in predicting longitudinal changes in BMI. Baseline data for 1258 children (50.7% males), mean age 6.32±1.52years, indicated the presence of five classes of sleep patterns: early/long sleepers (4.5%), normative sleepers (25.5%), late sleepers (49.9%), consistent late sleepers (11.1%) and early risers (9%). Late sleeping was significantly associated with longitudinal gains in BMI. Compared with early sleepers, consistent late sleepers experienced 1.03 unit gain in BMI at follow-up (95% CI: 0.001-2.05, P=.05). This study underscores the importance of looking beyond sleep duration and highlights the positive outcomes of early bedtimes in children. As sleep timing is modifiable, this offers the opportunity for improvement in sleep and protecting against future weight gain in indigenous children.

Association Between Late Bedtime and Diabetes Mellitus: A Large Community-Based Study.

The aim of this study was to investigate the association of bedtime with the prevalence of diabetes mellitus (DM) based on a large community-based population. In total, 5,420 participants (2,574 males and 2,846 females; aged 63.5 ± 11.0 years) from the Sleep Heart Health Study database were selected in this study. Sleep habit was recorded based on a questionnaire administered to patients upon recruitment. Bedtime was categorized as 11:00 pm and before, 11:00 pm to 12:00 am, and 12:00 am and later in the current study. Multivariate logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) to determine the relationship between bedtime and the prevalence of DM. The distribution of weekday bedtime at 11:00 pm and before, 11:00 pm to 12:00 am, 12:00 am and later was observed in 3,316 participants (61.2%), 991 participants (18.3%), and 1,113 participants (20.5%), respectively. Meanwhile, individuals with weekday bedtime of 12:00 am and later had a higher prevalence of DM than those with bedtime at 11:00 pm to 12:00 am, and 11:00 pm and before (10.6% versus 5.7% versus 6.6%, respectively; P < .001). In the adjusted multivariate logistic regression model, bedtime at 12:00 am and later on a weekday was significantly associated DM prevalence (OR 1.446, 95% CI 1.107-1.888, P = .007). No significant association was found between weekend bedtime and DM. Late bedtime at 12:00 am and later on a weekday may be a risk factor for the prevalence of DM. Stable sleep timing leads to lower risk of DM deserves future exploration.

An Educational Intervention to Improve the Sleep Behavior and Well-Being of High School Students.

The objective of this study was to determine whether a sleep education intervention improves knowledge of sleep, sleep behaviors, and depression in high school freshmen. We recruited student volunteers at a single magnet high school in Los Angeles, California through their health class. Twenty-four freshmen participated and 18 students (17 female, 1 male) completed pre- and postsurveys. Curriculum consisted of 4 hours of after-school interactive lectures emphasizing sleep physiology, benefits of sleep, what impacts sleep, and methods to improve sleep, followed by a 9-week sleep behavior change journal. Pre- and postsurveys measuring both sleep behaviors and knowledge, and a Patient Health Questionnaire-9 depression screening were administered to participants prior to and after the intervention. We used t tests and χ 2 tests to analyze knowledge and behavior change. Subjects improved in average sleep hours per night (preintervention 6.9 hours to postintervention 7.8 hours, P=.0134), and average weekend night bedtime (11:36 pm to 10:54 pm, P=.0307). This school sleep behavior intervention demonstrated students' average sleep hours per night and weekend bedtime improved after the lecture and sleep journal intervention. This suggests a sleep education intervention may benefit this population. Further studies are needed to demonstrate effectiveness of this education over time, across sexes, and in high-risk students.