Earlier Bedtime and Its Effect on Adolescent Sleep Duration.

We aimed to investigate the effect of increased sleep pressure and shortened sleep duration on subjective sleep perception in relation to electroencephalographic sleep measures. We analyzed the data from a study in which 14 healthy male volunteers had completed a baseline assessment with 8hr time in bed, a sleep deprivation (40hr of wakefulness) and a sleep restriction protocol with 5hr time in bed during 7 nights. In this work, we assessed perception index, derived through dividing the subjectively perceived total sleep time, wake after sleep onset and sleep latency duration by the objectively measured one at each condition. We found that total sleep time was subjectively underestimated at baseline and shifted towards overestimation during sleep restriction and after deprivation. This change in accuracy of subjective estimates was not associated with any changes in sleep architecture or sleep depth. Wake after sleep onset was significantly underestimated only during sleep restriction. Sleep latency was always overestimated subjectively without any significant change in this misperception across conditions. When comparing accuracy of subjective and actimetry estimates, subjective estimates regarding total sleep time and wake after sleep onset deviated less from electroencephalography derived measures during sleep restriction and after deprivation. We conclude that self-assessments and actimetry data of patients with chronic sleep restriction should be interpreted cautiously. The subjectively decreased perception of wake after sleep onset could lead to overestimated sleep efficiency in such individuals, whereas the underestimation of sleep time and overestimation of wake after sleep onset by actimetry could lead to further underestimated sleep duration.

To describe the sleep patterns and problems in children aged between 12 and 36 mo of age. This cross sectional survey was collected over a span of 1 y in Advanced Pediatric Centre, PGIMER, Chandigarh and crèches of Chandigarh. Children in the age group of 12 to 36 mo were included in study. Children with chronic illness, developmental delay, seizure disorder and lack of consent were excluded. A total of 368 children were enrolled. Main outcome measures were sleep duration over 1 to 3 y of life; sleep behavior at onset, during and waking of sleep and parent reported sleep problems and their predictors. The average duration of sleep was 12.5 h (S.D = 1.9). The mean total sleep duration and mean day time sleep duration decreased, while mean night time sleep increased as the age advanced from 12 to 36 mo. Following were the frequency of sleep habits seen in the index study; bed time routine was seen only in 68(18.5 %), a regular bed time ritual was seen in 281(76.4 %), 329(89.4 %) children frequently required 0-20 min time to fall asleep, 11(3 %) parents used sleep inducing drugs. Night waking (1 to 3 times a night) was seen in 297(80.7 %) and its frequency declined with age. Parent reported sleep problems were seen in 12.8 % (47/368). Lack of co-sleeping and night waking were considered as strongest predictors of parent reported sleep problems. Toddlers' sleep duration, night waking behavior, and day time naps decrease as the age progress while night time sleep duration increases with age. Lack of co-sleeping and night waking are considered as strongest predictors of parent reported sleep problems.

ObjectiveAlthough sleep is essential for healthy child development, parents generally misconstrue definitions of sleep duration and sleep quality. This study examines differences between objective and parent-reported measures of sleep in children, with a particular focus on Latino and non-Latino groups. We hypothesized that significant discrepancies exist between objective and subjective sleep measures and differences in sleep outcomes between Latino and non-Latino subgroups.MethodsChildren in grades one, two, and three in Rhode Island (n = 102; age range 6–10 years; 57.8% female) wore an accelerometer for seven days to objectively measure time in bed, sleep duration, wake after sleep onset, and sleep latency. Parents also reported perceived sleep outcomes, and whether they believed their child generally “sleeps the right amount”. Emphasis was placed on the Latino population.ResultsBased on parent-reported sleep measures, 83.3% of children met sleep guidelines (defined as 9–12 h per night), compared to 14.7% based on accelerometry (ρ = −0.036, p = 0.711). Average sleep duration significantly differed between parent reports (9.58 h, SD = 1.42) and actigraphy (8.32 h, SD = 0.70; ρ = 0.405, p < 0.001). There were no discrepancies between objective and subjective reported sleep latency and WASO, although paired tests indicated significant within-person differences in WASO (p < .001). Finally, there were significant discrepancies in sleep duration between Latinos and non-Latinos, with Latino caregivers reporting significantly shorter sleep and their children experiencing shorter sleep duration as measured via actigraphy, and being less likely to meet sleep guidelines.ConclusionThese findings suggest that there is a discrepancy between perceived and objectively measured sleep. It also suggests discrepancies in sleep duration between Latino and non-Latino children, and differences in parental knowledge of sleep behaviors between Latinos and non-Latinos.

Introduction Little is known about the factors during total sleep deprivation (TSD) and psychological stress that affect recovery sleep. We determined the relative contributions of cognitive and cortisol measures, which represent distinct domains, as predictors of recovery sleep timing and duration. Methods We conducted a five-day experiment under highly controlled conditions in 32 healthy adults (ages 27-53; 14 females). Salivary cortisol samples were collected during 1) TSD morning (TSD AM; after 25h of TSD) and 2) TSD evening following a modified Trier Social Stress Test, which induced psychological stress (TSD PM; after 34h of TSD). Digit Span Test (DS), Digit Symbol Substitution Test (DSST), and Psychomotor Vigilance Test (PVT) performance data were collected at 0400h, 1130h, and 1730h during TSD and averaged. Wrist actigraphy assessed sleep indices during the first recovery night following TSD (10h time in bed). Multiple linear regression models determined the impact of TSD cognitive and cortisol measures as predictors of recovery sleep timing and duration. The models and independent variables were all significant (p&amp;lt; 0.05). Results Sleep Onset. Each 1-point DS total # correct increase predicted a 0.042h later sleep onset and each 1 µg/dL AM cortisol increase predicted a 0.958h later sleep onset. Sleep Offset. In addition, each 1 PVT lapse increase predicted a 0.031h later sleep offset and each 1 µg/dL PM cortisol increase predicted a 1.205h earlier sleep offset. Sleep Duration. Each 1 PVT lapse increase predicted a 2.153 minute sleep duration increase, and each 1 µg/dL AM cortisol increase predicted an 87.367 minute sleep duration decrease. In addition, each 1-point DSST # correct increase predicted a 1.657 minute sleep duration decrease and each 1 µg/dL PM cortisol increase predicted a 100.535 minute sleep duration decrease. Across models, 35.8%-40.6% of the sleep timing and duration variance was explained, with r ranges between 0.598-0.637. Conclusion Our results elucidate the important roles of cognitive performance and cortisol metrics obtained during sleep loss in influencing recovery sleep timing and duration, suggesting the possibility of intervening on these measures to modify subsequent sleep. Our findings highlight hypothalamic-pituitary-adrenal axis and cognitive measures as biomarkers for recovery sleep health. Support (if any) NASA NNX14AN49G, 80NSSC20K0243 (NG)

Associations between the macronutrient composition of the evening meal and average daily sleep duration in early childhood

A strong association exists between sleep duration and glycemic control in patients with type 2 diabetes (T2D), yet convincing evidence of a causal link remains lacking. Improving sleep is increasingly emphasized in clinical T2D treatment guidance, highlighting the need for effective, scalable sleep interventions that can affordably serve large populations through mobile health (mHealth). This study aims to pilot an intervention that extends sleep duration by modifying bedtime behavior, assessing its efficacy among short-sleeping (≤6 hours per night) patients with T2D, and establishing robust evidence that extending sleep improves glycemic control. This randomized, single-blinded, multicenter study targets 70 patients with T2D from 9 institutions in Japan over a 12-week intervention period. The sleep extension intervention, BedTime, is developed using the Theory of Planned Behavior (TPB) and focuses on TPB's constructs of perceived and actual behavioral control (ABC). The pilot intervention combines wearable actigraphy devices with SMS text messaging managed by human operators. Both the intervention and control groups will use an actigraphy device to record bedtime, sleep duration, and step count, while time in bed (TIB) will be assessed via sleep diaries. In addition, the intervention group will receive weekly bedtime goals, daily feedback on their bedtime performance relative to those goals, identify personal barriers to an earlier bedtime, and select strategies to overcome these barriers. The 12-week intervention period will be followed by a 12-week observational period to assess the sustainability of the intervention's effects. The primary outcome is the between-group difference in the change in hemoglobin A1c (HbA1c) at 12 weeks. Secondary outcomes include other health measures, sleep metrics (bedtime, TIB, sleep duration, total sleep time, and sleep quality), behavioral changes, and assessments of the intervention's usability. The trial commenced on February 8, 2024, and is expected to conclude in February 2025. Patient recruitment ended on August 29, 2024, with 70 participants enrolled. The intervention period concluded on December 6, 2024, and the observation period ended on February 26, 2025, with 70 participants completing the observation period. The data analysis is currently underway, and results are expected to be published in July 2025. This trial will provide important evidence on the causal link between increased sleep duration and improved glycemic control in short-sleeping patients with T2D. It will also evaluate the efficacy of our bedtime behavior change intervention in extending sleep duration, initially piloted with human operators, with the goal of future implementation via an mHealth smartphone app. If proven effective, this intervention could be a key step toward integrating sleep-focused mHealth into the standard treatment for patients with T2D in Japan. Japan Registry of Clinical Trials jRCT1030230650; https://jrct.niph.go.jp/latest-detail/jRCT1030230650. DERR1-10.2196/64023.

The COVID-19 pandemic has raised numerous concerns regarding its effects on individuals' health and lifestyle. We aim to analyze potential changes in adolescent sleep patterns from before and during the pandemic and identify specific predictors of changes. A subgroup of adolescents from a population-based birth cohort from Pelotas, Brazil, was assessed pre-pandemic (T1, November-2019 to March-2020) and peri-pandemic (T2, August-2021 to December-2021) in in-person interviews (n = 1,949). Sleep parameters, including sleep duration and latency time on workdays and free days, as well as social jetlag (SJL), were assessed using the Munich ChronoType Questionnaire (MCTQ). Socio-demographic, pre-pandemic, and pandemic-related predictors were analyzed. Changes in sleep parameters from T1 to T2 were estimated by multivariate latent change score modeling. The latent change factor shows a significant mean increase in workday sleep duration (M = 0.334, p < 0.001), workday sleep latency (M = 0.029, p = 0.002), and free day sleep latency (M = 0.021, p = 0.034), and a decreased in SJL (M = -0.758, p < 0.001) during the pandemic. Female adolescents presented higher increases in workday sleep duration. Adolescents who adopted a stricter social distancing level during the pandemic presented greater increases in workday sleep duration and smaller reductions in SJL. Self-evaluated insomnia during the pandemic predicted lower increases in workday and free day sleep duration and higher increases in workday and free day sleep latency. The COVID-19 outbreak brought certain advantages regarding increased sleep duration and reduced SJL. However, the observed increase in sleep latency and the influence of self-reported insomnia could be related to psychological distress inherent to the pandemic.

Patients with cancer can often experience insomnia or sleep disturbances. This study aimed to explore whether the discrepancy between a patient's desired time in bed and desired total sleep time (DBST index) can be used as a measurement tool for insomnia severity or sleep onset latency [SOL] in patients with cancer. This retrospective medical records review study gathered clinical information and scores from scales and indices such as the Insomnia Severity Index (ISI), Cancer-related Dysfunctional Beliefs about Sleep (C-DBS) scale, Patient Health Questionnaire-9 items (PHQ-9), State subcategory of State and Trait Anxiety Inventory, and the short form of the Fear of Progression Questionnaire. Sleep indices of time variables (bedtime, sleep onset time, and wake-up time), duration variables [SOL, time in bed (TIB), time in bed over 24 hours (TIB/d), and duration from wake-up time to bedtime (WTB)], and DBST index were calculated. ISI scores were predicted by the PHQ-9 (β = 0.34, P < 0.001), C-DBS scale (β = 0.17, P = 0.034), and DBST indices (β = 0.22, P = 0.004). Long SOL value was predicted by early bedtimes (β = -0.18, P = 0.045), short WTB durations (β = -0.26, P = 0.004), and high DBST index values (β = 0.19, P = 0.013). The DBST index was significantly correlated with both insomnia severity and SOL in patients with cancer.

To characterize sleep duration, timing and continuity measures in pregnancy and their association with key demographic variables. Multisite prospective cohort study. Women enrolled in the nuMoM2b study (nulliparous women with a singleton gestation) were recruited at the second study visit (16-21 weeks of gestation) to participate in the Sleep Duration and Continuity substudy. Women <18 years of age or with pregestational diabetes or chronic hypertension were excluded from participation. Women wore a wrist activity monitor and completed a sleep log for 7 consecutive days. Time in bed, sleep duration, fragmentation index, sleep efficiency, wake after sleep onset, and sleep midpoint were averaged across valid primary sleep periods for each participant. Valid data were available from 782 women with mean age of 27.3 (5.5) years. Median sleep duration was 7.4 hours. Approximately 27.9% of women had a sleep duration of <7 hours; 2.6% had a sleep duration of >9 hours. In multivariable models including age, race/ethnicity, body mass index, insurance status, and recent smoking history, sleep duration was significantly associated with race/ethnicity and insurance status, while time in bed was only associated with insurance status. Sleep continuity measures and sleep midpoint were significantly associated with all covariates in the model, with the exception of age for fragmentation index and smoking for wake after sleep onset. Our results demonstrate the relationship between sleep and important demographic characteristics during pregnancy.

Assess the short- and long-term stability of sleep duration in patients with insomnia and normal-sleeping controls. Observational short-term and prospective studies. Sleep laboratory. Patients with insomnia (n = 150) and controls (n = 151) were recruited from the local community or sleep disorders clinic. A subsample of 95 men from the Penn State Adult Cohort (PSAC) were followed up 2.6 y after their initial visit. Participants underwent a physical examination and 8-h polysomnography (PSG) recording for 3 consecutive nights (controls and insomniacs), or 2 single nights separated by several years (PSAC). Intraclass correlation coefficients (ICCs) assessed the stability of the variables total sleep time (TST), sleep onset latency (SOL), and wake after sleep onset (WASO). We also examined persistence of the first-night classification of "short" versus "normal" sleep duration on subsequent nights. Stability of TST, SOL, and WASO based on 1 night were slight to moderate in both patients with insomnia (ICC = 0.37-0.57) and controls (ICC = 0.39-0.59), and became substantial to almost perfect when based on the average of 3 nights (ICC = 0.64-0.81). We observed similar degrees of stability for TST and WASO in the longitudinal sample, with moderate stability based on a single night and substantial stability based on both nights. In examining the persistence of "short" and "normal" sleep duration, 71.4% (controls), 74.7% (patients with insomnia), and 72.6% (longitudinal sample) of participants retained their first-night classifications over subsequent nights. Sleep duration variables, particularly total sleep time based on 3 consecutive nights in both patients with insomnia and controls or two single-night recordings separated by several years, are stable and reflect a person's habitual sleep. Furthermore, a single night in the laboratory may be useful for reliably classifying one's sleep duration.

Introduction Colorectal cancer is one of the most common cancers worldwide. Patients with this disease may experience gut dysbiosis and various psychoneurological symptoms (PNS) including, sleep disturbance, psychological distress, and pain. Family caregivers involved in managing their day-to-day needs may also experience similar PNS. This study aimed to explore associations between sleep characteristics and the gut microbiome in patient-caregiver dyads stratified by the presence or absence of PNS. Methods Patients with colorectal cancer and their sleep-partner caregivers (20 dyads, 55.49 years old, 60% female patients) self-reported PNS using the Patient Reported Outcomes Measurement Information System (PROMIS) once, from which participants were categorized, using K-means clustering, into normal and symptomatic PNS subgroups. Participants also completed the Sleep Consensus Diary daily for 14 consecutive days, from which sleep characteristics (sleep duration, time in bed, sleep onset latency, wake after sleep onset, and sleep efficiency) were derived. Participants provided stool samples, from which gut microbiome features were investigated using shotgun metagenomic sequencing. MetaPhAn3 for taxonomy classification and MicrobiomeAnalyst2.0 for alpha and beta diversity assessment were employed. PNS subgroup differences in differential taxa abundance, alpha and beta diversity, and gut microbiome feature associations with sleep characteristics were tested separately for patients and caregivers. Results 55% of patients and 35% of caregivers were categorized into the symptomatic subgroup. Although no significant differences were observed in alpha and beta diversity between PNS subgroups, nine taxa were uniquely abundant in patients and five in caregivers (unadjusted p&amp;lt;.05) that differed between the PNS subgroups. Regarding sleep characteristics, among patients, greater sleep efficiency (p=.015), shorter time in bed (p=.043), and longer wake after sleep onset (p=.024) were associated with greater alpha diversity (assessed by the Simpson’s Diversity Index). However, no significant associations of sleep with alpha and beta diversity were found in caregivers. Conclusion Findings suggest sleep disturbance may be a psychoneurological contributor to gut dysbiosis in patients with colorectal cancer. Future investigations to elucidate bidirectional associations between sleep and gut health, one’s psychobehavioral impact on the partner’s gut microbiome, and other psychoneurological markers that are attributable to caregivers’ gut dysbiosis, with a larger sample and prospective longitudinal design, are warranted. Support (if any)

The objective of this study was to investigate the role of environmental factors in sleep duration among adolescents living in rural areas. A total of 1140 students (569 males), aged 1019 years, and attending two schools in rural regions in southern Brazil, completed a questionnaire about their sleep habits. Demographic data were also obtained. Prevalence ratios (PR) were estimated for the cases of more than 9 h of sleep on weekdays. Sleep duration in adolescents with and without electric lighting at home was analyzed. Average sleep duration at night was 9.63 (1.64) h on school-going days and 10.14 (2.42) h on weekends. The prevalence of adolescents sleeping for more than 9 h at night on school-going days was 58.3%. Older adolescents showed a tendency to delay their sleep onset times, which is associated with a reduction of sleep duration. Adolescents without electric lighting at home slept longer on school-going days (P < 0.001) and on weekends (P = 0.013) when compared to those with electric lighting at home. From multivariate analysis, age (P < 0.001), school schedule (P = 0.007) and work (0.042) were factors affecting sleep duration. In contrast to the data previously reported for urban populations, we found a high prevalence of adolescents sleeping for more than 9 h on school nights. Data on populations living in less industrialized regions reinforce the idea that technological advances are associated with the negative impact of sleep phase delay in adolescents.

Objectives To assess changes in duration, timing, and social jetlag in adolescent sleep during the COVID-19 pandemic and evaluate the impact of mood, physical activity, and social interactions on sleep. Study Design An online survey queried adolescents’ sleep before (through retrospective report) and during the initial phase of COVID-19 in May 2020. Adolescents (N = 3,494), 13–19 years old, in the United States (U.S.) answered questions about their current and retrospective (prior to COVID-19) sleep, chronotype, mood, and physical and social activities. Linear regression models were fit for time in bed, reported bed and wake times, and social jetlag during COVID-19, accounting for pre-COVID-19 values. Results Total reported time in bed (a proxy for sleep duration) increased on weekdays by an average of 1.3 ± 1.8 hours (p < .001) during COVID-19, compared to retrospective report of time in bed prior to COVID-19. During COVID-19, 81.3% of adolescents reported spending 8 hours or more in bed on weekdays compared to only 53.5% prior to COVID-19. On weekdays, bedtimes were delayed on average by 2.5 hours and wake times by 3.8 hours during COVID-19 compared to prior to COVID-19. On weekends, bedtimes were delayed on average by 1.6 hours and waketimes by 1.5 hours (all p’s < 0.001). Social jetlag of >2 hours decreased to 6.3% during COVID-19 compared to 52.1% prior to COVID-19. Anxiety and depression symptoms and a decline in physical activity during COVID-19 were associated with delayed bed and wake times during COVID-19. Conclusions During COVID-19, adolescents reported spending more time in bed, with most adolescents reporting 8 hours of sleep opportunity and more consistent sleep schedules. As schools return to in-person learning, additional research should examine how sleep schedules may change due to school start times and what lessons can be learned from changes that occurred during COVID-19 that promote favorable adolescent sleep.

Introduction Adverse Childhood Experiences (ACEs) are highly stressful events during the first 18 years of life that have been linked with adverse adult health outcomes. Sleep is an important behavioral risk factor for a myriad of health outcomes that have been linked to ACE exposure. A growing body of evidence indicates that ACEs are associated with low self-reported sleep durations, but these findings should be verified using objectively measured sleep characteristics. The purpose of this study was to examine associations of ACE exposure with actigraphy-measured sleep duration, timing, and variability. Methods Methods: In twenty-four young adults (20F/4M; mean±SD, age=24±5 y), we assessed ACE exposure using the 10-item ACE scale and measured sleep characteristics over a ≥6 day period using a wrist-worn actigraphy device. Participants with 0–1 ACEs were characterized as low-ACE (ACE-low, n=10) and participants with 2+ ACEs were characterized as moderate-high-ACE exposure (ACE-mh, n=14). Independent samples t-tests and Hedges’ g effect sizes were used to compare total sleep duration, bed-time, get-up time, time-in-bed, sleep onset latency and the standard deviation of bed time and total sleep duration between groups. Results Time-in-bed was greater in ACE-mh than in ACE-low (mean±SE difference=-60±25 min; p=0.027; g=-0.95), yet there was no difference in total sleep duration (-9±10 min; p=0.46; g=-0.37). This discrepancy was accompanied by a non-significant, but large-effect size difference between ACE-mh and ACE-low (-15±7 min; p=0.051; g=-0.83) in sleep onset latency. There were no differences between groups in either bed-time (p=0.34; g=0.39) or get-up time (p=0.35; g=-1.2), nor in either bed-time (p=0.84; g=-0.08) or total sleep duration (p=0.36; g=-0.37) variability. Conclusion In contrast to prior evidence based on self-report, our initial evidence indicates that ACE exposure is not linked with shorter sleep durations or higher sleep variability when measured using actigraphy. Instead, ACE exposure is linked to greater time in bed and greater sleep onset latencies, suggesting that individuals exposed to ACEs may have less efficient sleep. Support (if any) Support: Research reported in this publication was supported in part by the NCATS of the NIH (UL1TR002537) and by the Injury Prevention Research Center through the CDC (R49 CE003095).

Short sleep appears to elevate obesity risk in youth; however, sleep is a multidimensional construct, and few studies have investigated parameters beyond duration. The objective of this study was to investigate if sleep onset time, duration, latency and night waking frequency are independently associated with adiposity and weight status in UK adolescents. This was a cross-sectional observational study of 10,619, 13-15years olds. Adjusted linear and logistic regressions were used to investigate associations of self-reported sleep characteristics with adiposity markers (body mass index z-score and percent body fat) and weight status. Compared with a sleep onset before 10pm, later sleep timing was associated with higher adiposity and higher likelihood of overweight and obesity in boys (after midnight, odds ratio [95% confidence interval]: 1.76 [1.19-2.60]) and girls (between 11pm and 11:59pm: 1.36 [1.17-1.65]). Sleeping ≤ 8hr, compared with > 9-10hr, was associated with higher odds of overweight and obesity in both sexes (boys: 1.80 [1.38-2.35]; girls: 1.38 [1.06-1.79]), and so too was sleeping > 10hr in girls (1.31 [1.06-1.62]), indicating evidence for a U-shaped association. Also in girls, compared to a sleep latency of 16-30 min, sleep latencies ≥ 46min were associated with higher adiposity (46-60min, beta coefficient [95% confidence interval], percent body fat: 1.47 [0.57-2.36]) and higher likelihood of overweight and obesity (46-60min: 1.39 [1.05-1.83]), and often as opposed to never waking in the night was associated with higher adiposity (body mass index z-score: 0.24 [0.08-0.41]; percent body fat: 1.44 [0.44-2.44]). Sleep duration and timing in both sexes, and sleep quality in girls, appear to be independently associated with adiposity and weight status in adolescence, and may be important targets for obesity prevention.