Sleep Guidelines Research Articles

Adolescent sleep and technology-use rules: results from the California Health Interview Survey

ObjectivesThis study reports on adolescent sleep, technology-use rules at home, and their potential association using the 2017 California Health Interview Survey (CHIS). MethodsCHIS cross-sectional, representative survey data was collected between June-December 2017 via telephone. Weekday bedtimes, rise times, and night time in bed in the past week, as well as whether technology-use rules were implemented at home, were examined among 448 adolescent residents of California (mean age = 14.5, range = 12-17; 48% women). ResultsThe average weekday nightly time in bed was 9.04 hours among 12- to 13-year-olds and 7.89 hours among 14- to 17-year-olds. The majority reported having technology-use rules and those who did, spent 35 more minutes in bed. Although a significant relationship was found between having technology-use rules and earlier bedtime, one was not found for time in bed, when controlling for demographics. ConclusionsMany California adolescents do not meet recommended sleep guidelines. Yet, technology-use rules appear to be associated with earlier bedtime. Results have implications for policy-making and adolescent sleep interventions.

Indication of CPAP without a sleep study in patients with high pretest probability of obstructive sleep apnea.

To evaluate the performance of clinical criteria (CC) for diagnosis and initiation of empirical treatment with continuous positive airway pressure (CPAP) in patients with suspected obstructive sleep apnea (OSA) compared with the treatment decision based on sleep studies (polysomnography or respiratory polygraphy), guidelines, and experience of participating physicians. This was a simulated intention-to-treat study in a retrospective (G1) and prospective (G2) cohort. Four observers (two per group) called CC1 and CC2 reviewed the sleep questionnaires and indicated CPAP if the patients presented snoring, frequent apneas (≥ 3-4/week), body mass index (BMI) > 25 kg/m2, sleepiness (Epworth > 11), or tiredness (at least 3-4 times per week) and some comorbidity (hypertension, coronary/cerebrovascular event, diabetes). Ten independent observers formed two groups of five (FD1 and FD2) and were blinded to each other's opinion. These observers in FD1 and FD2 decided CPAP treatment based on guidelines of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) or guidelines of the American Academy of Sleep Medicine (AASM) and factored in their own opinion. Sensitivity (S), specificity (Sp), and positive/negative likelihood ratios (LR+/-) were calculated with the test method: CC1/2, and the reference method: majority decision of FD1/2. A total of 653 patients (264 women, 40%) were studied. Median age was 54 years, BMI 28 kg/m2, and apnea hypopnea index (AHI) 16.5 events/h. S ranged from 21 to 25% (p 0.60), Sp 96.1 to 97.6% (p 0.39), and LR+ of clinical criteria 6.4 to 8.9 (p 0.52). CPAP indication without a previous sleep study showed a low sensitivity (≅ 22%) but a specificity greater than 95% in patients with high pretest probability for OSA (snoring, report of frequent apneas, BMI > 25 kg/m2 and sleepiness or tiredness plus comorbidity).

A school-based sleep hygiene education program for adolescents in Japan: a large-scale comparative intervention study

Sleep hygiene education involves promoting good sleep habits in all aspects of lifestyle and behavior. In this study, we evaluated the effects of a sleep hygiene education program for Japanese high school students who did not have insomnia symptoms.Tenth-grade students (N = 2815; intervention, n = 1347; control, n = 1468) from 16 high schools in a provincial city in Japan participated in this cluster-controlled trial. In this program, teachers conducted a 5-min class based on various catchphrases once per week using teaching materials developed for this study (“Healthy Living Sleep Guidelines for High School Students”). Twelve classes were conducted. The baseline and follow-up surveys were performed. The difference between the groups was examined using an intention-to-treat principle with the full analysis set. We selected the generalized estimating equation for this analysis. The intention-to-treat analysis revealed that the intervention group presented significantly greater prevention of insomnia symptoms and short sleep duration (< 6 h) compared to the control group (adjusted odds ratio: 0.72 [95% confidence interval: 0.54–0.96], adjusted odds ratio 0.79 [95% CI 0.67–0.94]). However, there were no significant differences in odds ratios between the two groups for poor subjective sleep quality, excessive daytime sleepiness, and late bedtime.This sleep hygiene education program may be useful as a low-cost, highly valid, and accessible primary prevention method for insomnia symptoms. However, the applicability of this program for children of other ages and regions needs to be verified.

Sociodemographic Differences in Young Children Meeting 24-Hour Movement Guidelines.

Little is known about variation in meeting the 24-Hour Movement Guidelines (including physical activity [PA], sleep, and screen time [ST]) in early childhood. The aim was to evaluate sociodemographic differences in meeting the 24-Hour Movement Guidelines. Parents of 3-4 year old children reported sociodemographic information and ST. Sleep and PA were measured using accelerometry, and height and weight were objectively measured. The 24-Hour Movement Guidelines include daily PA (total PA: ≥3h; including ≥1h of moderate to vigorous), sleep (10-13h), and ST (≤1h). Meeting guidelines by age, sex, race, poverty level, and weight status were assessed using chi-square and linear regression models. Of 107 children, 57% were white and 26% lived in households at or below the poverty level. Most children met the PA (91.5%) and sleep (86.9%) guidelines, but few met ST (14.0%) or all 3 (11.3%) guidelines. African American children and children who lived at or below the poverty level were less likely to meet the sleep, ST, and all 3 guidelines compared with others (P < .01 for all). There were no other differences. These results suggest future interventions should focus on reducing differences in movement, namely in sleep and ST.

Do young children consistently meet 24-h sleep and activity guidelines? A longitudinal analysis using actigraphy.

Existing studies examining adherence to 24-h movement guidelines in young children are mostly cross sectional and have not assessed additional guidelines relating to activity intensity or regularity in sleep patterns. The aims of this study were to determine adherence to full sleep, activity, and sedentary behaviour guidelines from 1-5 years of age, whether adherence tracked over time, and how adherence was related to body composition cross sectionally and prospectively. Data were obtained from 547 children who were participants in a randomised controlled trial. At 1, 2, and 5 years of age, children wore Actical accelerometers 24-h a day for 5-7 days, height and weight were measured, and parents completed questionnaires on screen time and restraint (1 and 2 years only). A dual-energy x-ray absorptiometry (DXA) scan measured body composition at 5 years of age. Although adherence to general sleep and activity guidelines was high, few children had regular sleep patterns. Adherence to all three guidelines ranged from 12.3 to 41.3% at the different ages, although these estimates decreased to 0.6-9.3% when activity intensity (60 min of energetic play) and sleep regularity (consistent sleep and wake times) were included. Children who met all three guidelines at a given age were more likely to meet all three guidelines at a subsequent age (odds ratio, 95% CI: 2.6, 1.04-6.4 at 1 year and 2.5, 1.1-5.9 at 2 years). However, adherence to meeting all three guidelines at earlier ages was not related to BMI z-score or body composition at age 5, either cross sectionally or prospectively. Strategies to promote adherence to movement guidelines among young children are warranted, particularly to reduce screen time, and encouraging regular sleep patterns.

A validation study of a consumer wearable sleep tracker compared to a portable EEG system in naturalistic conditions

ObjectiveTo compare a wearable device, the Fitbit Versa (FV), to a validated portable single-channel EEG system across multiple nights in a naturalistic environment. MethodsTwenty participants (10 men and 10 women) aged 25–67 years were recruited for the present study. Study duration was 14 days during which participants were asked to wear the FV daily and nightly. The study intended to reproduce free-living conditions; thus, no guidelines for sleep or activity were imposed on the participants. A total of 138 person-nights, equivalent to 76,539 epochs, were used in the validation process. Sleep measures were compared between the FV and portable EEG using Bland-Altman plots, paired t-tests and epoch-by-epoch (EBE) analyses. ResultsThe FV showed no significant bias with the EEG for the global sleep measures time in bed (TIB) and total sleep time (TST), and for calculated sleep efficiency (cSE = [TST/TIB] x 100). The FV had 92.1% sensitivity, 54.1% specificity, and 88.5% accuracy with a Cohen's kappa of 0.41, but a prevalence- and bias adjusted kappa of 0.77. The predictive values for sleep (PVS; positive predictive value) and wakefulness (PVW; negative predictive value) were 95.0% and 42.0%, respectively. The FV showed significant bias compared to the portable EEG for time spent in specific sleep stages, for SE as provided by FV, for sleep onset latency, sleep period time, and wake after sleep onset. ConclusionsThe consumer sleep tracker could be a useful tool for measuring sleep duration in longitudinal epidemiologic naturalistic studies albeit with some limitations in specificity.

Prevalence and Correlates of Meeting Sleep, Screen-Time, and Physical Activity Guidelines Among Adolescents in the United Kingdom

This analysis of the UK Millennium Cohort Study examines the associations between sleep, physical activity, and screen time in adolescents aged 14 years in the United Kingdom.

Infant Safe Sleep Program Expansion

Background: Unsafe sleep conditions are potential contributing factors in up to half of all unexpected or unexplained infant deaths in New York State. Despite this many parents are not taught and do not follow the AAP safe sleep guidelines. Evidence suggests that parents can learn and retain safe infant sleep habits. A program was implemented in 2015 at Maria Fareri Children’s Hospital (MFCH) Newborn Nursery and NICU with the NYS Perinatal Quality Collaborative (NYS DOH initiative) to improve modeling of safe sleep through nurse training, parent education with knowledge-based questionnaires, …

Environmental noise and sleep and mental health outcomes in a nationally representative sample of urban US adolescents.

Environmental noise has been linked to negative health outcomes, like poor sleep, poor mental health, and cardiovascular disease, and likely accounts for more than 1 million disability-adjusted life years annually in Western Europe. Adolescence may be a particularly sensitive period for noise exposure due to an increased need for sleep, failure to meet sleep guidelines, and increased risk for first onset of some mental health disorders. However, the potential health effects of living in high-noise environments have not been studied in US adolescents, rarely in European adolescents, and mental health outcomes studied have not corresponded to diagnoses from the Diagnostic and Statistical Manual of Mental Disorders (DSM). Using a US-based nationally representative survey of urban adolescents (N = 4,508), we estimated associations of day-night average sound levels exceeding the US Environmental Protection Agency's 55 decibel limit with sleep outcomes and lifetime mental health DSM diagnoses. We implemented doubly robust targeted minimum loss-based estimation coupled with propensity score matching to account for numerous potential adolescent, household, and environmental confounders. Living in a high- versus low-noise Census block group was associated with later bedtimes on weeknights (0.48 hours, 95% confidence interval [CI] = -0.15, 1.12) and weekend nights (0.65 hours, 95% CI = 0.37, 0.93), but not with total hours slept. Associations between living in a high- versus low-noise Census block group and mental disorders were mixed, with wide CIs, and not robust to sensitivity analyses. We find evidence for an association between residence in a high-noise area and later bedtimes among urban adolescents but no consistent evidence of such an association with mental health disorders.

Improving Safe Sleep Compliance in a Pediatric Inpatient Unit and Newborn Nursery Using Quality Improvement Methodology from the American Academy of Pediatrics Education and Safe Sleep Environment (EASE) Project

Background: In the United States, approximately 3,500 babies under one year of age die from sleep related complications. Enforcing safe sleep practices (sleeping alone, on their back, in a crib or bassinette) in the hospital setting increases adherence to this practice after discharge. However, a majority of health care providers do not promote safe sleep guidelines. The American Academy of Pediatrics offers the Education and Safe Sleep Environment (EASE) project to improve infant safe sleep environments in the hospital and to increase parental education about safe sleep. Objective: …

Active Gaming Prevalence and Correlates by Type of Day in Spanish Youth.

Active gaming has emerged as a new option to foster physical activity in youth. The aim of this study was to estimate the prevalence of active gaming in adolescents, to determine differences between active and nonactive gamers by type of day, and to examine predictors of being an active gamer. A cross-sectional study was conducted with 3095 Spanish adolescents aged 12 to 18 years who self-reported their involvement in moderate to vigorous physical activity, sedentary behaviors, and active gaming. Those engaging in active gaming for at least 10 minutes per day were considered active gamers. Student's 2-tailed t tests, chi-square test, and binomial logistic regression were performed. About 25.9% of the adolescents were active gamers. They were younger, had higher body mass index, and spent more time on moderate to vigorous physical activity, television viewing, and sedentary video games with computer/console than nonactive gamers. There were more active gamers on weekends than on weekdays. On weekdays, more males than females were active gamers. Adolescents who did not meet sleep time guidelines were more likely to be active gamers on weekdays, whereas on weekends, being a girl, overweight/obese, and having a high socioeconomic status were predictors of being an active gamer. Because active gaming may contribute to meeting physical activity guidelines, the present findings could enable better targeting of physical activity promotion programs.

Prevalence of Meeting Physical Activity, Screen-Time, and Sleep Guidelines Among Children and Adolescents With and Without Visual Impairments in the United States.

The purpose of this study was to compare the degree to which children and adolescents with and without visual impairments (VIs) met national physical activity, screen-time, and sleep guidelines. This observational, cross-sectional analysis of the 2016 National Survey of Children's Health focused on children (age 6-12yr) and adolescents (age 13-17yr) with and without VIs. The sample included 241 (weighted n = 472,127) and 17,610 (weighted n = 28,249,833) children, and 255 (weighted n = 505,401) and 17,417 (weighted n = 20,071,557) adolescents with and without VIs, respectively. Chi-square statistics were computed to examine the degree to which participants with and without VIs met health-behavior guidelines. Children (p = .02) with VIs were less likely to meet screen-time guidelines, but adolescents with VIs were not (p = .87). VI status was not associated with the likelihood of meeting physical activity or sleep guidelines (p < .05). Low numbers of children and adolescents with and without VIs meeting health-behavior guidelines warrant targeted interventions aimed at enhancing engagement.

Body Mass Index, Physical Activity, Sedentary Behavior, Sleep, and Gross Motor Skill Proficiency in Preschool Children From a Low- to Middle-Income Urban Setting

Limited research reports on the relationship between body mass index (BMI) and physical activity (PA), sedentary behavior (SB), sleep, and gross motor skills (GMS) in low- and middle-income countries. The aim of this study was to (1)describe BMI, PA, SB, sleep duration, and GMS proficiency in South African preschool children and (2)identify relationships between variables. BMI, including z scores for height, weight, and BMI were determined. Seven-day PA, SB, and sleep were measured using accelerometry. GMS were assessed using the Test of Gross Motor Development (second edition). Associations were explored by comparing sleep, PA, SB, and GMS between BMI tertiles using the Kruskal-Wallis test. Most (86%) children (n = 78, 50% boys) had a healthy BMI (15.7 [1.3]kg/m2). Children spent 560.5 (52.9)minutes per day in light- to vigorous-intensity PA and 90.9 (30.0) minutes per day in moderate- to vigorous-intensity PA; most (83%) met the current PA guideline. Nocturnal sleep duration was low (9.28 [0.80]h/d). Although daytime naps increased 24-hour sleep duration (10.17 [0.71]h/d), 38% were classified as short sleepers. Around half (54.9%) of participants complied with both PA and sleep guidelines. No associations between variables were found. Despite being lean, sufficiently active, and having adequate GMS, many children were short sleepers, highlighting a possible area for intervention.

Objective sleep and physical activity using 24-hour ankle-worn accelerometry among toddlers from low-income families

ObjectivesPoverty is a risk for short sleep duration and limited physical activity. This study describes sleep, physical activity, and sedentary behavior of Women, Infants, and Children–eligible toddlers and the proportion of toddlers meeting recommendations for sleep and physical activity, and examines associations with body mass index z scores and poverty. Participants/measurementsA total of 101 toddlers (12-32 months) from low-income families (62% African American) wore 24-hour ankle accelerometers over 3-7 consecutive days. Concurrent validity for daytime napping was assessed using parent-reported toddler wake/sleep between 08:00 and 20:00 collected using Ecological Momentary Assessment. Logistic regressions predicted odds of meeting guidelines. ResultsToddlers averaged 10.56 hours of sleep in 24 hours. All toddlers averaged ≥180 minutes of total activity per day, 38% had ≥60 minutes of moderate/vigorous physical activity per day, 32% of toddlers slept between 11 and 14 hours over 24 hours, and 26% had a bedtime before 9:00 pm. Body mass index z score was not associated with meeting guidelines. Poverty was associated with less than 60 minutes of moderate/vigorous physical activity. ConclusionsMost toddlers were not meeting sleep guidelines. This study provides objective data on sleep and activity among a diverse sample of low-income toddlers. Objective measures of sleep and physical activity facilitate surveillance of children meeting guidelines for sleep and physical activity. Such norms are needed to examine disparities among children from varying racial and economic backgrounds. Future research should examine if meeting guidelines is related to other health indicators.

Association Between Meeting Physical Activity, Sleep, And Dietary Guidelines And Cardiometabolic Risk Factors And Adiposity In Adolescents

INTRODUCTION: Obesity is a complex disease that may be influenced by physical activity (PA), sleep, and diet; though little is known if individual behavior guidelines are related to cardiometabolic risk factors. PURPOSE: To examine the association between meeting PA, sleep, and dietary guidelines and cardiometabolic risk factors and adiposity in adolescents. METHODS: Adolescents, ages 10 to 16 years, wore an accelerometer for 7 days, including overnight to capture PA and sleep. The PA guideline was defined as ≥ 60 minutes of moderate-to-vigorous PA per day. The sleep guideline was 9-11 hours (10-13 years of age) or 8-10 hours (14-16 years of age) per night. The dietary guideline was based on the Healthy Eating Index 2015 score calculated from a self-administered dietary recall. Scores ≥70 were classified as meeting guideline. Cardiometabolic risk factors were assessed in a clinical setting including body mass index percentile (BMIP); waist circumference (WC); DXA for total body fat; abdominal MRI for visceral adipose tissue (VAT); resting blood pressure (BP); and a fasting blood draw for high-density lipoprotein cholesterol, triglycerides, and glucose. Generalized linear regression was used to assess meeting the guidelines and cardiometabolic risk factors, with adjustment for age, sex, race, and other guidelines. RESULTS: Of the 342 participants, 239 (69%) provided complete measures. Adolescents were 12.4 ± 1.9 years of age, most were white (61%), had overweight or obesity (47%), and slightly more were girls (53%). Many met the sleep guideline (50%), but few met the PA (11%) or dietary (3%) guidelines. Most met 1 (50%) or no guidelines (43%), and few met 2 or more guidelines (6%). In adjusted models, meeting the PA guideline was associated with a lower BMIP, diastolic BP, WC, VAT, and total body fat; and meeting the sleep guideline was associated with a lower WC (p<0.05 for all). Meeting one guideline was associated with a lower BMIP, WC, VAT, and total body fat; and meeting 2 guidelines was associated with lower diastolic BP (p<0.05 for all). There were no other associations between meeting guidelines and risk factors. CONCLUSIONS: Adiposity was lower for those who met the PA or sleep guidelines, and very few met the dietary guideline. Multidisciplinary strategies are needed to ensure healthy behaviors for all adolescents.

Pilot evaluation of the Sleep Ninja: a smartphone application for adolescent insomnia symptoms

ObjectivesThe aim of this study was to test the feasibility, acceptability and preliminary effects of a recently developed smartphone application, Sleep Ninja, for adolescent sleep difficulties.SettingThe study was conducted online...

Adherence to sleep guidelines reduces risk of overweight/obesity in addition to 8-5-2-1-0 guidelines among a large sample of adolescents in the United States

ObjectivesTo examine whether adherence to US sleep, dietary, screen time, and physical activity (8-5-2-1-0) guidelines is associated with reduced risk of overweight/obesity in adolescents. DesignMultivariable log-binomial regressions were estimated using the 2017 Youth Risk Behavior Surveillance System data. ResultsOf the 8194 adolescents aged 13 years and older, only 0.6% (49) met all guidelines. Meeting the recommended 8 hours of sleep per day was associated with reduced risk of overweight/obesity (risk ratio [RR]: 0.90; confidence interval [CI]: 0.81-0.99). Having ≤2 hours of screen time per day was associated with reduced risks of overweight/obesity (RR: 0.85; CI: 0.77-0.95). One hour of daily physical activity was associated with reduced risk of overweight/obesity (RR: 0.80; CI: 0.73-0.87). No significant associations were found between daily consumption of ≥5 fruits and vegetables or consumption of zero sugar-sweetened beverages and overweight/obesity. The 8-5-2-1-0 constitutes an improved prediction model to explain the risk of overweight/obesity among adolescents compared with the 5-2-1-0 model (F1,36 = 4.80; P = .035). ConclusionsFindings from this study suggest that meeting recommendations for sleep, screen time, and physical activity is associated with decreased risk of overweight/obesity in a large sample of adolescents. These are important factors to consider in the prevention and treatment of overweight/obesity in adolescents.

Mothers’ experiences of settling infants in central Vietnam “through their eyes”: A photo-elicitation study

There is little research on beliefs and practices regarding unsettled infant behavior and infant sleep in low and lower-middle income countries such as Vietnam. Here, researchers used a participatory qualitative visual method (photo-elicitation) to investigate how infant settling was perceived “through the eyes” of new mothers in Central Vietnam. Four qualitative themes emerged from the data: “loneliness in the midst of the crowd”, “finding the right position”, “protecting from cold”, and “affection and exhaustion”. Further research into how parenting programs and evidence based infant sleep guidelines can be modified to be socially acceptable in Vietnam is recommended.

Meeting the 24-hr movement guidelines: An update on US youth with autism spectrum disorder from the 2016 National Survey of Children's Health.

The purpose of this study was to examine how adherence to the physical activity (PA), screen-time (ST), and sleep duration guidelines differ between youth with autism spectrum disorder (ASD) and youth with typical development (TD). A secondary objective was to assess how PA, ST, and sleep duration varied among youth with ASD by age and ASD severity. Utilizing the 2016 National Survey of Children's Health data, parental reports of time spent by youth in PA, ST, and sleep were used to determine adherence to the 24-hr movement guidelines for 1008 youth with ASD and 34 489 youth with TD. Multivariate logistic regression analyses determined that children with ASD were less likely to meet the guidelines for PA, ST, and sleep duration, and adolescents with ASD were less likely to meet the guidelines for PA and ST than participants with TD. Furthermore, logistic regression analyses determined adolescents with severe ASD to be less likely to meet the sleep guideline compared to adolescents with mild ASD. Overall, youth with ASD were significantly less likely to adhere to all three guidelines. The findings highlight the breadth of health behaviors that require intervention to counteract the poorer health status among youth with ASD. Autism Res 2019, 12: 941-951. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: New health recommendations suggest children and adolescents should have at least 1 hr of physical activity, no more than 2 hr of screen-time (e.g., television), and 9-11 hr of sleep (or 8-10 hr for children aged 14 or older) every day. This article looked at how children and adolescents with autism meet these new guidelines. The two main results were that: (a) children with autism were less likely to meet all three guidelines compared to children without autism, and (b) adolescents with autism were less likely to meet the guidelines for physical activity and screen-time.

Association between weekend catch-up sleep and health-related quality of life of Korean adults.

Sleep debt is known to have harmful effects on health. Weekend catch-up sleep (CUS) is a behavior to cope with weekday sleep debt. However, it is unclear whether weekend CUS has advantageous effects on health because sleep hygiene guidelines recommend regularizing bed time and arousal time. The aim of this study was to identify whether weekend CUS behavior has an association with better health-related quality of life (HRQoL)According to the inclusion criteria, 4871 participants were selected from the 2016 Korea National Health and Nutrition Examination Survey. Sleep questionnaires and European quality of life scale-5 dimensions (EQ-5D) questionnaire were used to collect data about the participants’ sleep patterns and HRQoL. Odds ratios (ORs) with 95% confidence intervals (95% CIs) for each dimensional problem of EQ-5D were derived by logistic regression. Mean EQ-5D index scores were compared between weekend CUS and non-CUS groups based on their weekday sleep durations and quintile of chronotype.The ORs of dimensional problems of HRQoL of non-CUS group versus weekend CUS group were 1.63 (95% CI 1.07, 2.47) for usual activities, and 1.45 (95% CI 1.11, 1.90) for anxiety/depression. Mean EQ-5D scores of the weekend CUS group were significantly higher than those of the non-CUS group for sleeping less than 6 hours (0.953 ± 0.004 vs 0.936 ± 0.007, P = .036) and sleeping 6 to 7 hours (0.965 ± 0.003 vs 0.955 ± .0.004, P = .045). These findings were similar in the fourth quintile (Q4) of chronotype (0.965 ± 0.007 vs 0.951 ± 0.008, P = .008) and fifth quintile (Q5) (0.952 ± 0.006 vs 0.941 ± 0.007, P = .022).Weekend CUS behavior was associated with better HRQoL than non-CUS among Korean adults. Especially, it was significant in participants who slept for less than 7 hours or participants whose chronotype was the fourth or fifth quintile. Attention may be needed for subjects with sleep short time and later chronotype who do not have weekend-CUS behaviors, because there is a risk that their HRQoL might be compromised.