Late Bedtime Research Articles

Association of self-reported dental caries with sex, lifestyle, and problematic Internet use among elementary school children in Japan.

Dental caries is the most prevalent disease in elementary schoolchildren in Japan. Problematic Internet use (PIU) has increased among children; however, its association with caries has rarely been studied. We aimed to explore (1) sex differences in dental caries and (2) the association of dental caries with lifestyle and PIU among elementary school children in Japan. From 110 elementary schools in Toyama Prefecture, 13,413 children in the 4th-6th grades (mean age, 10.5 years) participated in the Toyama Safe Internet Use Project in 2018. We inquired about lifestyle, anthropometric data, family rules for screen time, PIU, and the number of self-reported treated caries. PIU was assessed using the Young's Diagnostic Questionnaire. We defined children having ≥ 3 caries as having multiple caries. Subsequently, a modified Poisson regression analysis was performed. Overall, 12,146 children (90.7%) were analyzed. The prevalence of multiple caries was 25.7% (24.4% in boys and 27.0% in girls). In the regression analysis, the presence of multiple caries was significantly associated with being a girl(adjusted prevalence ratio (aPR) 1.13), being in higher grades (5th grade: aPR 1.13 and 6th grade: aPR 1.14), skipping breakfast (aPR 1.11), having late bedtime (10 to 11 p.m.: aPR 1.17 and ≥ 11 p.m.: aPR 1.23), tooth brushing (once a day: aPR 1.14 and not every day: aPR 1.41), having no family rules (aPR 1.20), and PIU (YDQ score 3-4: aPR 1.17). When stratified by sex, a dose-response relationship was observed between PIU and the presence of multiple caries in boys (YDQ score 3-4: aPR 1.19 and YDQ score ≥ 5: aPR 1.22). Being a girl, having an undesirable lifestyle, and PIU were significantly associated with multiple self-reported caries. In addition to a having a healthy lifestyle, restricting PIU is recommended to prevent caries in children.

Late Bedtime from the Perspective of Adolescents: A Qualitative Study.

Later sleep timing is a key determinant of reduced sleep duration and quality in adolescents and is associated with negative mental and physical outcomes. However, little is known about adolescents' views on late bedtime. The study's purpose is to explore adolescents' perspectives on why they go to sleep late during school nights and what would help them to go to bed earlier. We conducted online semi-structured interviews with 24 adolescents aged 14-17 years as a part of the international HBSC (Health Behaviour in School-aged Children) study. The data were collected via individual and group interviews and analyzed using a combination of consensual qualitative research methodology and thematic analysis. School demands and leisure time activities, particularly online socialization with peers, have been identified as one of the main themes related to why adolescents go to sleep late. Adolescents reported difficulties managing these competing activities during the day after school, often postponing them until late at night and prioritizing them to sleep. Adolescents also mentioned bedtime distress as a barrier to falling asleep. However, some adolescents did not perceive late bedtime as a problem, but rather as a habit and personal choice. They reported that better time management, less homework, engagement in physical activity, parent-set bedtime, and less time spent online in the evening would help them to go to bed earlier. Our findings suggest that interventions to improve sleep timing in adolescents should focus on reducing school pressure, building supportive social networks; strengthening adolescents' self-regulation skills; and enhancing parental involvement in establishing sleep and daily routines for their adolescents.

Are the Sleep-Wake Cycle and Sleep Duration Ethnically Determined? A Comparison of Tibetan and Japanese Children's Sleep.

Several environmental factors affect sleep. We investigated the sleep and sleep-related habits of preschool children living in Tibet and conducted an international comparison with those in Japan. We conducted a community-based cross-sectional study using the Chinese version of the Japanese Sleep Questionnaire for Preschoolers (JSQ-P-C) and compared the results with previous data on Japanese children. The sleep status of 3113 children aged 3-6 years old in Qinghai province was evaluated. The average wake time and bedtime of the Tibetan children were 7:20 ± 0:31 and 21:16 ± 0:43, respectively. Their mean nocturnal sleep duration was 10.0 ± 0.7 h. In comparing 3-year-old children, the time for which they viewed TV in Tibet was shorter (65.5 ± 44.6 min) than that in Japan (149.7 ± 76.6 min), and the mother's bedtime was earlier in Tibet (21:28 ± 2:14) than in Japan (23:20 ± 1:05). However, the bedtime and sleep duration of the Tibetan children (21:17 ± 0:37 and 10.0 ± 0.7 h) were fairly similar to those of the Japanese children (21:24 ± 1:57 and 9.8 ± 0.8 h). The late bedtime and short nocturnal sleep duration of Tibetan toddlers were the same as those of Japanese toddlers despite considerable differences in their lifestyle and environment.

Associations between bedtime media use and sleep outcomes in an adult population-based cohort

Abstract Background We aimed to extend existing research on associations between bedtime media use and sleep in adults by taking relevant covariates into account and testing hypothesised mediating and moderating pathways. Methods Frequency of bedtime media use and sleep outcomes were examined by questionnaire in 4188 adults (59% women, aged 19-94 years) from the Specchio cohort in Geneva, Switzerland. We tested: 1) associations between bedtime media use and sleep (bedtimes, sleep latency, sleep duration, sleep quality, insomnia symptoms, and daytime sleepiness), adjusting for prior sleep, mental health, and health behaviours (physical activity, binge drinking, smoking, total leisure screen time), 2) whether bedtime media use mediates associations between individual susceptibility factors (age, chronotype, and mental health) and sleep, and 3) whether individual susceptibility factors moderate associations between bedtime media use and sleep. Results Often using a screen in the 30 minutes before going to sleep at night was associated with a late bedtime (≥midnight; OR [95% CI]=1.90 [1.44, 2.51], p < 0.001), short sleep duration (<7 hours; 1.21 [1.01, 1.46], p < 0.05), and excessive daytime sleepiness (Epworth score >9; 1.47 [1.25, 1.74], p < 0.001) after adjustment for all covariates. Bedtime media use partly mediated the association between younger age and an evening chronotype and these sleep outcomes. Mental health moderated the association between bedtime media use and sleep quality/insomnia, such that the former was associated with poorer sleep quality/insomnia among individuals with better mental health, but not among those with poorer mental health. Conclusions Frequent bedtime media use was associated with various sleep outcomes, independently of relevant covariates. Limiting the use of screens at bedtime is important to promote sleep among adults. Individuals with poorer mental health likely require additional support to improve their sleep quality. Key messages • Frequent bedtime media use is associated with a late bedtime, short sleep duration, and more daytime sleepiness in adults, and these associations hold after adjustment for relevant covariates. • Frequent bedtime media use mediates the association between individual susceptibility factors and sleep outcomes. Mental health moderates the association between bedtime media use and sleep quality.

Sleep timing and the prevalence of hypertension in middle-aged and older populations: the sleep heart health study

ObjectivesSleep characteristics such as duration, continuity, and irregularity are associated with the risk of hypertension. This study aimed to investigate the association between sleep timing (including bedtime, wake-up time, and sleep midpoint) and the prevalence of hypertension.MethodsParticipants were selected from the Sleep Heart Health Study (n = 5504). Bedtime and wake-up times were assessed using sleep habit questionnaires. The sleep midpoint was calculated as the halfway point between the bedtime and wake-up time. Restricted cubic splines and logistic regression analyses were performed to explore the association between sleep timing and hypertension.ResultsA significant nonlinear association was observed between bedtime (Poverall<0.001; Pnonlinear<0.001), wake-up time (Poverall=0.024; Pnonlinear=0.076), sleep midpoint (Poverall=0.002; Pnonlinear=0.005), and the prevalence of hypertension after adjusting for potential confounders. Multivariable logistic regression showed that both late (> 12:00AM and 23:01PM to 12:00AM) and early (≤ 22:00PM) bedtimes were associated with an increased risk of hypertension compared to bedtimes between 22:01PM and 23:00PM. In addition, individuals with late (> 7:00AM) and early (≤ 5:00AM) wake-up times had a higher prevalence of hypertension than those with wake-up times ranging between 5:01AM and 6:00AM. Delaying the sleep midpoint (> 3:00AM) was also associated with an increased risk of hypertension. Furthermore, no significant interaction effect was found in the subgroup analyses stratified by age, sex, or apnea-hypopnea index.ConclusionsOur findings identified a nonlinear association between sleep timing and hypertension. Individuals with both early and late sleep timing had a high prevalence of hypertension.

Latent profiles of multi-dimensional sleep characteristics and association with overweight/obesity in Chinese preschool children

ObjectivesTo examine the association between latent profiles of multi-dimensional sleep characteristics and overweight/obesity (OWO) in Chinese preschool children. Study designThe cross-sectional analysis included 3204 preschool children recruited from 24 kindergartens in Shanghai. Parents reported children's demographics and sleep characteristics, including sleep duration, timing and disturbances. Latent profile analysis (LPA) was used to identify sleep subtypes. Logistic regression models were used to evaluate the associations between sleep characteristics/subtypes and OWO. ResultsShort sleep duration, late bedtime, long social jetlag and sleep disturbances were significantly associated with increased OWO. However, when considering the interplay of sleep duration and timing, there was no significant association between sleep duration and OWO for children sleeping later than 22:00. Three sleep subtypes were identified based on children's sleep duration, timing and disturbances: "Average Sleepers" (n = 2107, 65.8 %), "Good Sleepers" (n = 481, 15.0 %), and "Poor Sleepers" (n = 616, 19.2 %). "Good Sleepers" had reduced odds of being OWO (AOR, 0.72; 95 % CI, 0.56–0.93) compared to "Average Sleepers", while "Poor Sleepers" showed an increased risk of OWO (AOR, 1.36; 95 % CI, 1.11–1.67). ConclusionsThese findings highlight that improving multiple sleep characteristics simultaneously is a promising option to prevent and intervene childhood obesity.

Late Bedtime and Altered Diurnal Axial Length Rhythms of the Eye

Purpose Affecting one-third of the population worldwide and increasing, the sight-threatening condition myopia is causing a significant socio-economic burden. To better understand its etiology, recent studies investigated the role of ocular and systemic rhythms, yet results are conflicting. Here we profiled 24-h variations of axial length of the eye and salivary melatonin concentration in young adults with and without myopia and explored the potential impacts of bedtime on these rhythms. Methods A total of 25 healthy young adults (age 25.0 ± 4.8 years, 13 females) completed this study, including 13 myopes (mean spherical equivalent refractive error −2.93 ± 1.46 diopters) and 12 non-myopes (0.14 ± 0.42 diopters). Saliva sample collection and axial length measurements were repeated for seven times over 24 h starting from 8 am. Information on sleep and chronotype was collected at first visit with the Pittsburgh Sleep Quality Index and the Morningness-Eveningness Questionnaire. Results Significant diurnal rhythms of axial length and salivary melatonin concentration were identified in both refractive groups (both p < 0.001), with no myopia-related rhythm difference (interaction of measurement time-point × myopia, p = 0.9). Late bedtime was associated with altered rhythms (p = 0.009) and smaller diurnal change (p = 0.01) in axial length. Elevated melatonin levels were observed in myopes (p = 0.006) and in late sleepers (p = 0.017). Conclusions These findings suggest that sleep/wake cycles may be involved in the regulation of axial length rhythms. Further research is needed to determine if there exists a causal relationship between the two.

Regulation of dermal circadian pathways by a novel topical formulation.

Skin health is impacted by a wide range of intrinsic and extrinsic factors (J Dermatol Sci, 2017, 85, 152), including those that impact circadian rhythm, such as sleep disruption (Textbook of Aging Skin, 2016), UV (Biomed Aging Pathol, 2013, 3, 161) and blue light (Int J Cosmet Sci, 2019, 41, 558). Disruption of the skin's endogenous circadian balance, even by a consistently late bedtime, has deleterious effects on multiple measurements of skin health, including hydration, skin barrier protection, microbiome counts and skin regeneration, among others (Clin Cosmet Investig Dermatol, 2022, 15, 1051). Skin repair processes occur at night and help to maintain important aspects of skin health (FEBS Lett, 2021, 595, 2413). Interest is increasing in the development of topical products that help restore proper circadian function. This study demonstrates that a proprietary topical formulation regulates new and established gene and protein biomarkers of circadian entrainment and circadian rhythm, demonstrating the product's potential to maintain appropriate dermal diurnal balance.

Impact of Social Media Usage on Sleep and Eye Health: A Survey Study Among University Students

Social media has become essential for university students, particularly during the pandemic, however, excessive late-night use can disrupt sleep due to screen light and impacting overall well-being and academic performance. Therefore, it is important to examine the purposes for which social networking sites are used and the effect of social media on sleep health among students. For the present study exploratory research design was adopted and the data was collected through google forms. The results indicated that, majority of the students were female, highest per cent belonged to 20-24 years age group, nearly seventy per cent were under graduates, students were using all major social media platforms daily to know the latest news and to chat with friends. The high social media usage of social media had high impact on their vison and led to late bedtimes.

Social media use and sleep health among adolescents in Canada.

Public health concerns over the impact of social media use (SMU) on adolescent health are growing. We investigated the relationship between SMU and sleep health in adolescents in Canada aged 11 to 17 years. Data from the 2017-2018 Health Behaviour in School-aged Children study were available for 12 557 participants (55.2% female). SMU was categorized by frequency of use (non-active, active and intense) and the presence of addiction-like symptoms (problematic). Mixed effects logistic regression models identified associations between SMU and seven sleep health indicators (insomnia symptoms, daytime wakefulness problems, screen time before bed, meeting sleep duration recommendations, sleep variability and late bedtime on school and non-school days). Compared to active SMU, non-active SMU was associated with better sleep indicators, except for insomnia symptoms. Intense SMU was associated with greater odds of having poor sleep health indicators (adjusted odds ratio [aORs] from 1.09 to 2.24) and problematic SMU with the highest odds (aORs from 1.67 to 3.24). Associations with problematic SMU were greater among girls than boys, including having a later bedtime on school days (aOR = 3.74 vs. 1.84) and on non-school days (aOR = 4.13 vs. 2.18). Associations between SMU and sleep outcomes did not differ by age group. Intense and problematic SMU were associated with greater odds of poor sleep health among adolescents in Canada, with stronger associations among girls than boys. Further research is needed to understand the mechanisms underlying associations between SMU and sleep to inform public health recommendations.

Association of sleep timing, sleep duration, and sleep latency with metabolic syndrome in middle-aged adults in Korea: A cross-sectional and longitudinal study

ObjectiveSleep is a potential risk factor for metabolic syndrome. We investigated the associations of various sleep characteristics with the status and incidence of metabolic syndrome in middle-aged Koreans. MethodsUsing data from a community-based Korean Medicine Daejeon Citizen Cohort study on participants aged 30-50years, cross-sectional (n = 1984) and longitudinal (n = 1216, median follow-up: 2.1years) analyses were performed. To study the association of metabolic syndrome and five components with various sleep characteristics, measured using the Pittsburgh Sleep Quality Index, we used Poisson and logistic regression and Cox proportional hazard regression analyses, adjusting for covariates. ResultsOf 1984 participants, 66%, 19%, and 15% belonged to the non-metabolic syndrome, pre-metabolic syndrome, and metabolic syndrome groups, respectively. After covariate adjustments, the pre-metabolic syndrome group was associated with late mid-sleep time (≥5:00; prevalence ratios 1.61, 95% confidence interval 1.01-2.54) and late bedtime (≥2:00; prevalence ratios 1.55, 95% confidence interval 1.03-2.34), and the metabolic syndrome group was associated with long sleep latency (prevalence ratios 1.33, 95% confidence interval 1.03-1.73), poor sleep quality (prevalence ratios 1.38, 95% confidence interval 1.07-1.78), and early wake time (<6:00; prevalence ratios 1.29, 95% confidence interval 1.01-1.63). Longitudinal analysis of participants without metabolic syndrome at baseline indicated a significant increase in metabolic syndrome risk associated with very short sleep duration (<6 hours; hazard ratio 1.72, 95% confidence interval 1.06-2.79), long sleep latency (>30 minutes; hazard ratio 1.86, 95% confidence interval 1.1-3.12), and early wake time (<6:00 o’clock; hazard ratio 1.73, 95% confidence interval 1.01-2.97). ConclusionSleep characteristics, such as short duration, long latency, and early wake time, were associated with an increased risk of metabolic syndrome in middle-aged adults.

Inequities in adolescent sleep health in Aotearoa New Zealand: Cross-sectional survey findings

ObjectivesTo investigate ethnic inequities in, and social determinants of, adolescent sleep health in Aotearoa New Zealand. MethodsAnalysis of self-report data from a cross-sectional survey of secondary school students (12- to 18-year-olds). Analyses included weighted prevalence estimates of good and poor sleep health stratified by ethnicity, and multivariable logistic regression models concurrently adjusted for ethnicity, school year, gender, rurality, neighborhood deprivation, school decile, housing deprivation, sleeping elsewhere due to lack of adequate housing, unsafe environment, and racism. ResultsInequities in social determinants of health were evident for Māori (Indigenous peoples of Aotearoa New Zealand; n = 1528) and minoritized (Pacific n = 1204; Asian n = 1927; Middle Eastern, Latin American, and African [MELAA] n = 210; and ‘Other' ethnicity n = 225) adolescents. A greater proportion of Māori, Pacific, Asian, MELAA, and ‘Other' adolescents had short sleep, compared to European (n = 3070). Māori, Pacific, Asian, and MELAA adolescents were more likely to report late bedtimes (after midnight), and Māori, Pacific, and ‘Other' adolescents were more likely to report early waketimes (5 AM-6 AM or earlier), on school days. Rurality, neighborhood deprivation, school-level deprivation, housing deprivation, sleeping elsewhere due to inadequate housing, unsafe environments, and racism partially, but not fully, explained associations between ethnicity and short sleep, late bedtimes, and early waketimes. ConclusionsEthnic inequities exist in adolescent sleep health in Aotearoa New Zealand. Socio-political actions are needed to address racism and colonialism as root causes of ethnic inequities in adolescent sleep, to ensure all young people are afforded the basic human right of good sleep health and associated mental and physical well-being.

Association between Sleep and Language Development in Children with Congenital Zika Syndrome.

Congenital Zika Virus Syndrome (CZS) presents notable hurdles to neurodevelopment, with language development emerging as a crucial aspect. This study investigates sleep patterns and language skills in children with CZS, aiming to explore the potential synchronization of sleep development with their neurodevelopment. We studied cross-sectionally 135 children with CZS aged 0 to 48 months, investigating sleep using the BISQ Questionnaire. Language development was assessed using the Early Language Milestone Scale, while motor development and cognitive and social ability were assessed using the Bayley Scales of Infant and Young Child Development 3rd edition. We also studied longitudinally a cohort of 16 children (initially aged 0 to 12 months) whom we followed for four years, assessing at one-year intervals. Sleep disturbances and language deficits were highly frequent in this population. In the 0-12 months group, a late bedtime and frequent nighttime awakenings were associated with poorer auditory expressive skills. At 13-24 months, nighttime awakenings were associated with poorer auditory expressive skills, while among 25-36-month-olds decreased auditory receptive skills were associated with longer sleep onset latency and reduced nighttime sleep duration. The brain alterations caused by Zika virus infection affect both sleep disturbances and delays in language development. It is possible that sleep disturbance may be a mediating factor in the pathway between CZS and delayed language development, as the three analyzed language skills showed a correlation with sleep parameters.

Study of Sleep Parameters on Respiratory Health and School Performance in Urban Children

Background: Sleep plays a crucial role in maintaining the health and well-being of children, affecting their physical, psychological, and cognitive development. However, research has shown that sleep problems in children are increasingly prevalent, impacting their health and quality of life. Objective: To study the impact of sleep parameters on respiratory illnesses and school performance among children of age group 3 to 15 years. Methods: An observational, cross-sectional study was conducted using a validated questionnaire, in which 300 parents were asked about their children’s sleeping behaviours, as well as about the details of respiratory illness and school functioning. The children's growth parameters were also recorded. Results: 97% of children with early bedtimes (before 10 PM) were found to be more attentive in the class and 83.7% of them had a lower risk of respiratory illness than 82.2% and 52% children with of late bedtimes consecutively (P&lt;0.004). 93.9% of children with night sleep duration of &gt;8 hours, were more attentive and 69.5% of them had a lesser frequency of respiratory illnesses than 78.7% and 53.7% of those with night sleep of &lt;8 hours (P&lt;0.001). The most frequent cause of abnormal sleep behaviour was late-night screen use (25.7%), leading to overweight/obesity in the study population. Conclusion: Children with late bedtime, &lt;8 hours of night sleep, sleep latency &gt;30 minutes, and waking up difficulties had a higher risk of respiratory illnesses and poor school performance. Educating parents and teachers in early identification and correction of children with sleep disorders is very vital.

The association of self-reported sleep and circadian measures with glycemic control and diabetes complications among young adults with type 2 diabetes.

We aim to examine the association of sleep duration, sleep quality, late chronotype, and circadian misalignment with glycemic control and risk of complications in young adults with youth-onset type 2 diabetes followed in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) study. Self-reported sleep duration, quality, timing, and circadian misalignment were assessed via a modified Pittsburgh Sleep Quality Index (PSQI) questionnaire, and chronotype was assessed via the Morningness-Eveningness Questionnaire (MEQ). We examined diabetes complications including loss of glycemic control (defined as hemoglobin A1c ≥8%), hypertension, dyslipidemia, albuminuria, and diabetic peripheral neuropathy. Multivariable logistic regression models were constructed to assess associations between sleep and circadian measures with outcomes of interest, such as loss of glycemic control and diabetes complications. A total of 421 participants (34.2% male), mean age 23.6 ± 2.5 yr, mean body mass index (BMI) of 36.1 ± 8.3 kg/m2, and mean diabetes duration of 10.0 ± 1.5 yr were evaluated. Self-reported short sleep duration, daytime sleepiness, and sleep quality were not associated with loss of glycemic control or diabetes complications. Late self-reported bedtime (after midnight) on work/school nights, rather than self-expressed chronotype or circadian misalignment, was independently associated with loss of glycemic control. An association was seen between late bedtimes and albuminuria but was attenuated after adjusting for depression. In conclusion, late bedtime on work/school days, rather than short sleep duration, daytime sleepiness, or poor sleep quality, was independently associated with loss of glycemic control in this longitudinal cohort of young adults with youth-onset type 2 diabetes.NEW & NOTEWORTHY The prevalence of type 2 diabetes in youth is increasing at an alarming rate. Identifying potentially modifiable factors modulating glycemic control is critically important to reduce micro and macrovascular complications. In a large cohort of youth-onset type 2 diabetes, self-reported late bedtime on work/school days was independently associated with loss of glycemic control in this longitudinal cohort of young adults with youth-onset type 2 diabetes.

Network analysis of smoking-related sleep characteristics in Chinese adults

The associations between multiple sleep characteristics and smoking behavior are inconsistent, and it is unclear which sleep characteristics are most crucial for tobacco prevention. This study aimed to explore the associations between smoking status/intensity and multiple sleep characteristics and to identify the potential core domain of smoking-related sleep using network analysis. Data were obtained from a survey of cancer-related risk factors among Chinese adults. Logistic regression models were used to quantify the associations between sleep characteristics and smoking status/intensity. Network analyses were employed to identify the core sleep characteristics. A total of 5,228 participants with a median age of 44 years old were included in the study. Current smoking was significantly positively associated with long nap time, difficulty falling asleep, late bedtime, getting up after 7 am, and waking up earlier than expected. There was significant positive association between current smoking and short sleep duration in young adults under 45 years old. Late bedtime and getting up after 7 am were only associated with current heavy smoking, but not current light smoking. Network analyses showed that multiple smoking-related sleep characteristics were interconnected, with difficulty falling asleep and late bedtime as central characteristics in the network. The study found that the associations between sleep characteristics and smoking varied by age and smoking intensity and highlights the potential benefits of sleep health promotion in smoking cessation, with a particular focus on difficulty falling asleep and late bedtime.

Late bedtime combined with more screen time before bed increases the risk of obesity and lowers diet quality in Spanish children

This cross-sectional study aimed to investigate whether the combination of bedtime and screen time (ST) before bed were associated with obesity and diet quality in toddlers and school-aged children. Parents reported children's bedtimes and ST before bed (0 min, 1–30 min, >30 min). We then defined bed + screen time behavior using bedtime median cut-offs (early [EB] or late [LB]) and ST responses, resulting in four groups: EB–0′ST, EB ≤ 30′ST/LB–0′ST, EB > 30′ST/LB ≤ 30′ST, and LB > 30′ST. For all participants (n = 1133; 5.4 ± 2.7 years, 49.7% girls, 51.9% school-aged) we evaluated body mass index (BMI), diet quality, sleep-related variables, physical activity, and health-related quality of life (HRQoL). Outcome variables were compared across bed + screen time behavior groups, stratified by age group (toddlers and school-aged children) using general linear models for continuous variables, as well as chi-squared tests or logistic regressions for categorical variables. Additionally, we calculated linear p-trends. Analyses were adjusted for sociodemographic variables, BMI, and physical activity (unless the variable was tested). The results showed that toddlers and school-aged children in the LB ≥ 30′ST group were more likely to have overweight/obesity (OR: 3.42 [95%CI:1.41,8.26] and OR: 2.53 [95%CI:1.10,5.03], respectively) than those in the EB–0′ST group. Additionally, toddlers and school-aged children in the EB > 30′ST/LB ≤ 30′ST and LB > 30′ST groups showed significantly lower adherence to the Mediterranean diet compared to the other groups (p < 0.001). Regarding sleep-related outcomes, we observed that the combination of LB and more ST was associated with poorer sleep quality and shorter sleep duration in toddlers and school-aged children (p < 0.001). These findings emphasize the importance of promoting earlier bedtimes and limiting ST before bed as part of obesity prevention strategies for children. Furthermore, such intervention could benefit the quality of children's diet and overall lifestyle.

Prevalence of Poor Sleep Quality and its Association with Lifestyle Habits, Competition-Based Activities, and Psychological Distress in Japanese Student-Athletes During the COVID-19 Pandemic.

Objectives The present study clarified the prevalence of poor sleep quality and its relation to lifestyle habits, competitive-based activities, and psychological distress among Japanese student-athletes in the initial pandemic period (2020) and 1 year later (2021). Methods In the present study, student-athletes were defined as individuals belonging to university athletic clubs. The data of two cross-sectional surveys (2020: n = 961 and 2021: n = 711) were collected from student-athletes in 6 universities in Japan. First, the prevalence of poor sleep quality (Pittsburgh sleep quality index score > 5) was investigated. Relationships between poor sleep quality and lifestyle habits, competition-based activities, and psychological distress were then explored using multivariate logistic regression analysis adjusted for age, sex, and body mass index. Results The prevalence of poor sleep quality was 33.6% in 2020 and 36.6% in 2021. Poor sleep quality in 2020 was related to late bedtime, taking supplements before bed, part-time job (no late night), stressors of expectations and pressure from others, and psychological distress, whereas that in 2021 was related to early wake-up time, skipping breakfast, taking caffeinated drinks before bed, use of smartphone/cellphone after lights out, stressors of motivation loss, and psychological distress. Conclusions In both 2020 and 2021, one-third of student-athletes had poor sleep quality and psychological distress was its common risk factor. Lifestyle habits and competition stressors associated with poor sleep quality were pandemic-specific in 2020, but similar to the prepandemic period in 2021.

Sleep timing behaviour, sleep duration and adherence to obesogenic dietary patterns from pre-school to school age: results from the Portuguese birth cohort Generation XXI.

In an obesogenic environment, short sleeping may increase opportunistic eating. The timing of sleep might also influence the drive to eat. This study investigated the prospective association of sleep timing and duration with diet in 5286 children from the Portuguese birth cohort Generation XXI, evaluated at 4 and 7 years of age. At 4 years, sleep duration was categorised into ≤10 and >10 h. Four sleep timing categories were generated based on the median split for sleep-onset and -offset times: 'Early Sleep-Early Wake'; 'Early Sleep-Late Wake'; 'Late Sleep-Early Wake'; 'Late Sleep-Late Wake'. At 7 years, diet was obtained by a food frequency questionnaire and three dietary patterns were included: 'Healthier', 'Energy-Dense Foods (EDF)' and 'Snacking'. The Healthy Eating Index was used to evaluate diet quality. Multinomial logistic regression models and generalised linear models were performed. Children who had a late sleep, independently of the time of waking up, had higher odds of following the 'EDF' pattern, compared with the 'Healthier'. Boys who had late sleep and/or late wake had also higher odds of following the 'Snacking' pattern and had poorer diet quality. In both sexes, a late sleep or late wake were associated with a lower diet quality, compared to the group 'Early Sleep-Early Wake', and independently of nap behaviour. In boys, shorter sleep duration was associated with a poorer diet. In conclusion, pre-schoolers with late bedtimes or wake-up times have worse dietary patterns and poorer diet quality at the age of 7 years, which seems to be independent of sleep duration.

Sleep Characteristics of an International Sample of Adult Gamers

Abstract Introduction About 65% of adult Americans report playing video games. Despite potential impacts to functioning, there is limited research on the relationship between video game use and sleep, specifically among adults. The present study expands upon the literature by describing demographic, video game, and sleep characteristics of an international adult sample of gamers. Methods The participants were 3,481 adults aged 18 to 74 who responded to an online questionnaire about video game use (i.e., quantity of play, most common game type), general sleep characteristics (i.e., sleep onset latency [SOL]; duration, sleep timing, and sleep quality), and gaming-specific sleep disruptors (i.e., game-related night awakenings and sleep delays). Most identified as cisgender male (79.8%) and white (77%). Results Participants reported an average SOL of 24.63 minutes, and most (64.5%) had a sleep duration from 7 to 9 hours with an overall average of 8.42 hours. Most (58.7%) reported that their sleep quality was fair to very poor. Bed and wake times were generally delayed, with 51% reporting a late evening or early morning bedtime and an average wake time of 8:28 am. A majority (81.2%) indicated that their bedtime was delayed due to game-related activities, but game-related night awakenings were less common. Conclusion Although many report a sufficient amount of sleep, adult gamers tend to report sleep disruptions in other domains, particularly regarding a delayed sleep schedule and poor sleep quality. This may be attributable to game-related bedtime delays or other game-specific factors (e.g., game type) that should be evaluated in the future.