Understanding Sleep-Wake Behavior in Late Chronotype Adolescents: The Role of Circadian Phase, Sleep Timing, and Sleep Propensity

Circadian phase in high-school students: weekday-weekend shifts and relationships to other sleep/circadian characteristics

STUDY OBJECTIVES

In a sample of high-school students, (1) to characterize within-person changes in sleep and circadian characteristics from school nights to weekend nights, (2) to examine whether later circadian phase relates to weekday-weekend changes in sleep/circadian characteristics, and (3) to examine correlations between biological and proxy measures of circadian phase.

METHODS

Sample included 95 high-school students reporting at least one drink of alcohol in their lifetime. Participants completed baseline self-report measures, wrist actigraphy for 8 days, and two overnight laboratory visits (Thursday and Sunday) for salivary melatonin sample collection. Circadian phase was calculated as the dim light melatonin onset (DLMO; 4 pg/mL threshold). Proxy circadian phase measures included the Composite Scale of Morningness (CSM), Munich Chronotype Questionnaire (MCTQ), and actigraphy-based midsleep.

RESULTS

Other than nap duration, all examined actigraphy-based sleep characteristics, DLMO, and DLMO-sleep phase angles showed weekday-weekend differences (adjusted p-value < .05). Later mean DLMO was associated with larger weekday-weekend changes in total sleep time (b = 0.39, padjusted = .010). CSM and actigraphy-based midsleep showed small-to-moderate (rho = ~0.3) and moderate (rho = ~0.5) correlations with DLMO, respectively, but chronotype based on the MCTQ was not correlated with DLMO.

CONCLUSIONS

In the largest published sample to date, circadian phase substantially shifted from the school week to weekend, underscoring the "social jetlag" imposed by early school start times. Similarly, teens with the latest circadian phase exhibited the greatest weekend catch-up sleep. Finally, perhaps due to the instability of circadian phase in this context, self-reported proxies for circadian timing were poor approximations of biological circadian phase.

Association between sleep timing shifts and dietary quality in Korean high school girls during COVID-19: a cross-sectional study

BACKGROUND/OBJECTIVES

Owing to coronavirus disease 2019 (COVID-19), the shift from offline to online classes has caused significant changes in high school students' daily habits, including sleep patterns and dietary intake. This study explored the association between sleep schedule fluctuations and dietary quality among high school girls during the COVID-19 pandemic. This study examined the association between bedtime, wake-up time, and adolescent dietary quality during the weekly online/offline school period among 517 high school girls in Incheon, South Korea.

SUBJECTS/METHODS

The participants were divided into 2 groups: normal sleepers (n = 244), who maintained normal sleep schedules defined as a midpoint between bedtime and wake-up time before 5:30 a.m., during in-person and online classes; and late sleepers (n = 273), who maintained a normal sleep schedule during in-person classes but exhibited late sleep patterns defined as a midpoint after 5:30 a.m., during online classes.

RESULTS

Shorter sleep duration was characteristic of late sleepers with circadian rhythm disruption, who also displayed poorer dietary quality, including higher consumption of caffeinated beverages and street food and never consuming breakfast. Among the 5 constituent factors, disrupted sleep timing was associated with lower Nutrition Quotient for Adolescents scores in total, moderation, and environment. This association persisted independent of the grade level, even after adjusting for school grade. These findings highlight the significant effect of sleep patterns on dietary habits.

CONCLUSION

This study highlights the significant relationship between disrupted circadian rhythms and poor dietary quality among high-school girls. These findings reveal the need for interventions to promote healthy sleep patterns as a strategy to improve the dietary quality and overall health of adolescents.

Associations between multiple sleep dimensions and suicide and non-suicidal self-injury: a cross-sectional study of 3828 Chinese young people

PURPOSE

Suicide and non-suicidal self-injury (NSSI) are preventable concerns in young people. Suicidal ideation (SI), suicidal plans (SP) and suicidal attempt (SA) are closely related to death. Sleep problems are known risk factors for suicide and NSSI. This study aimed to explore the relationship between sleep, suicidality and NSSI.

METHODS

Participants were 3,828 middle school and college students aged 11-23 years from urban and rural areas of Henan Province. Sleep, suicidal phenomena and NSSI were assessed by applying self-reported questionnaires. Chi-squared tests were utilized to demonstrate the demographic data and sleep variables. The correlation between sleep, suicidality and NSSI were explored by using binary logistic regression, while adjusting socio-demographic characteristics with multivariate models.

RESULTS

Sleep variables except mid-sleep time were related to suicidal phenomena (P < 0.05). Greater social jet lag (SJL) [≥ 2 h (h)] was associated with increased risk of SI [Odds ratios (OR) = 1.72, 95% confidence intervals (CI):1.40-2.11], SP (OR = 2.10, 95%CI:1.59-2.79) and SA (OR = 1.50, 95%CI:1.00-2.26). Non-only child participants with SJL (≥ 2 h) had significantly increased odds of SI (OR = 1.75, 95%CI: 1.41-2.18) and SP (OR = 2.25, 95%CI: 1.66-3.05). Eveningness chronotype had the strongest correlation with SI (OR = 3.87, 95%CI:2.78-5.38), SP (OR = 4.72, 95%CI:2.97-7.50), SA (OR = 6.69, 95%CI:3.08-14.52) and NSSI (OR = 1.39, 95%CI:1.02-1.90).

CONCLUSION

Overlong or short sleep duration, SJL, eveningness chronotype and other sleep abnormalities (e.g., daytime dysfunction, low sleep efficiency) were associated with a higher prevalence of SI, SP and SA. Additionally, eveningness was significantly correlated with NSSI among young people. These findings suggested the importance of assessing and intervening in sleep habits to prevent suicide and NSSI in young people.

Sex Differences in Circadian Timing and Biological Night in Adolescents

Circadian rhythms, intrinsic 24-h cycles that drive rhythmic changes in behavior and physiology, are important for normal physiology and health. Previous work in adults has identified sex differences in circadian rhythms of melatonin, temperature, and the intrinsic period of the human circadian timing system. However, less is known about sex differences in circadian rhythms at other developmental stages. To address this gap, we considered a secondary analysis of sleep and circadian data from two studies involving adolescent participants during the academic year: (n = 32, 15 females). We collected 1 week of in-home actigraphy data to calculate sleep-wake parameters and in-laboratory salivary melatonin data collection in dim-light conditions was used to compute dim-light melatonin onset (DLMO) and offset (DLMOff) using a threshold of 4 pg/mL. We found that DLMO was an average of 96 min earlier, the time between DLMO and bedtime was an average of 56 min greater, and the biological night (time between DLMO and DLMOff) was 60 min longer in females compared to males, even though bedtimes and waketimes were not statistically different between the groups. In addition, after accounting for differences in bedtime, sex was still a significant predictor of DLMO. Conversely, no evidence was found indicating a difference in DLMOff or the phase angle between DLMOff and waketime by sex. These findings suggest that sex differences in circadian rhythms are present in adolescents and may have implications for circadian health during this important developmental period.

Validation of the Morningness-Eveningness Scale for Children (MESC) with ambulatory circadian monitoring of temperature, light exposure and activity

The external validity of the Morningness-Eveningness Scale for Children was analysed via objective measures of skin temperature, light exposure and motor activity with the ambulatory circadian monitoring methodology. A total of 138 adolescents (57 boys and 81 girls) aged 12-13 years, who in addition to completing the Morningness-Eveningness Scale for Children to determine their circadian typology wore a wrist activity device (Kronowise 3.0; Kronohealth SL) during school days and a weekend, participated. Circadian parameters, such as mesor, amplitude and acrophase, were estimated for skin temperature, light exposure and motor activity, as were sleep parameters, such as risetime, bedtime and social jetlag. The results indicated that during the weekend E-type adolescents experienced later acrophases in temperature, light and activity than I-type and M-type adolescents did, whereas boys experienced earlier acrophases in temperature and activity. When school weekdays were compared with the weekend, there was a weekend delay in the acrophases of temperature (1:03), light exposure (2:03) and activity (3:15). The results obtained in this study provide external validity for applying the Morningness-Eveningness Scale for Children in the naturalistic context of high school while considering sex and type-of-day differences as important variables in chronopsychological studies.

Chronotype, sleep quality, depression and pre-sleep rumination: A diary and actigraphy study

Eveningness has been associated with both disturbed sleep and depression. It is unclear, however, if deprived sleep explains evening types' vulnerability to depression. The role of pre-sleep rumination in these associations also remains understudied. The present study assessed the relationship between eveningness and sleep quality, as well as the possible mediating effect of pre-sleep rumination and the moderating effect of a history of depression, under naturalistic conditions. Eighty-eight Dutch-speaking participants (87.5% females, 21.4 ± 3.7 years) were selected on the basis of their non-intermediate chronotype using the Morningness Eveningness Questionnaire (evening types (n = 53); morning types (n = 35)). Depression status was assessed through a diagnostic interview (healthy (n = 61); remitted depressed (n = 27)). Participants' sleep characteristics were monitored via actigraphy and sleep diaries for seven consecutive days and nights. Pre-sleep rumination was measured via a self-report questionnaire. Evening types had longer subjective and actigraphic sleep onset latency than morning types. Pre-sleep rumination did not mediate the former associations but predicted longer subjective sleep onset latency. Furthermore, the relationship between chronotype and subjective sleep onset latency was moderated by depression history. Remitted depressed evening types reported longer sleep onset latency than healthy evening and morning types, possibly posing the former at a higher risk for depressive relapse. Overall, the current findings address the need to further investigate the physiological signature of circadian rhythms and sleep latency. This could serve as a foundation for the development of prevention and early intervention programs, tailored for mood and sleep disorders.

Influence of chronotype on sleep quality and menstrual regularity in nurses on monthly shift rotations

OBJECTIVES

This study aimed to investigate factors that influence the sleep quality and menstrual cycles of female rotating-shift nurses.

METHODS

A cross-sectional study was conducted in which 213 female rotating-shift nurses between the ages of 20 and 45 were recruited from a medical center in Taiwan from November 1, 2023, to December 31, 2023. Binary logistic regression analysis was performed with regard to sleep quality or menstrual cycle.

RESULTS

Female rotating-shift nurses who perceived a higher level of stress (P < .001), were late chronotypes (P = .020), or were working the night shift (P = .006) were more likely to have poor sleep quality. Late-type nurses working the day shift were more likely to have poor sleep quality than were early- and intermediate-type nurses (P < .001). With regard to menstrual cycles, female rotating-shift nurses who perceived a higher level of stress (P = .008), were working the night shift (P < .001), or had poor sleep quality (P = .001) were more likely to have irregular menstrual cycles. Late-type nurses working the day shift were more likely to have irregular menstrual cycles than were early- and intermediate-type nurses (P = .013).

CONCLUSIONS

A higher likelihood of poor sleep quality was found in female rotating-shift nurses when they perceived high levels of stress, and the interactions between chronotype and shift type could influence sleep quality. Shift type and the interactions between chronotype and shift type could also influence menstrual regularity.

Sleep and daytime functioning in children with tourette syndrome: A two-week case-control study with actigraphy and cognitive assessments

There is increasing recognition of the high prevalence of sleep issues in children with Tourette syndrome (TS), a condition characterised by motor and vocal tics. Overnight polysomnography (PSG) has been the primary mode of sleep assessment in the TS literature, despite the extensive use of actigraphy in other neurodevelopmental populations. As a result, there are existing research gaps surrounding day-to-day variability of sleep in TS and links to daytime functioning. This study adopts a naturalistic, intensive longitudinal design to examine sleep in children with TS while considering potential links to tic severity and daytime functioning. Participants were 34 children aged between 8 and 12 years (12 with TS, 22 neurotypical controls). Wrist actigraphs tracked sleep-wake cycles across two weeks and a battery of scales and cognitive assessments measured sleep disturbances and daytime functioning. Mixed models using N = 476 nights of actigraphy data found that relative to controls, children with TS had significantly increased time in bed, increased sleep onset latency, reduced sleep efficiency, lower subjective sleep quality, but comparable actual sleep time. Higher self-report tic severity at bedtime did not predict increased sleep onset latency. In the sleep disturbance scale, 83.33 % of children with TS met the clinical cut-off for a sleep disorder. Parent-report emotional, behavioural, and executive difficulties were greater in the TS group relative to controls, but performance on cognitive tasks was comparable between groups. Together, findings highlight sleep disturbances as an important clinical factor to consider in the management of TS, though further research is required to substantiate findings in larger-scale studies. This study demonstrates the feasibility of assessing sleep via actigraphy in children with TS, supporting more widespread use in the future.

Chronotypes and their association with sleep quality among Chinese college students of Anhui Province: a cross-sectional study

OBJECTIVES

To describe the prevalence of chronotype and sleep quality among Chinese college students and explore the relationship between chronotype and sleep quality.

DESIGN

A cross-sectional study.

SETTING

Four colleges and universities in Anhui, China, between November and December 2020.

PARTICIPANTS

A total of 4768 college students were recruited using a stratified, multistage, cluster sampling survey.

OUTCOME MEASURES

Morningness-Eveningness Questionnaire 19 was used to determine the chronotype of the students and the Pittsburgh Sleep Quality Index (PSQI) was used to measure their sleep quality. The multiple logistic regression model was used to explore the potential association between chronotype and sleep quality.

RESULTS

The self-reported proportions of evening-type (E-type), neutral-type and morning-type among college students were 51.17%, 45.14% and 3.69%, respectively. The mean PSQI score was 4.97±2.82 and the prevalence of poor sleep quality was 18.2%. After adjusting the covariates by multiple logistic regression analysis, E-type was positively associated with subjective sleep quality (OR=1.671, 95% CI 1.414 to 1.975), sleep latency (OR=1.436, 95% CI 1.252 to 1.647), sleep duration (OR=2.149, 95% CI 1.506 to 3.067), habitual sleep efficiency (OR=1.702, 95% CI 1.329 to 2.180), daytime dysfunction (OR=1.602, 95% CI 1.412 to 1.818) and overall poor sleep quality (OR=1.866, 95% CI 1.586 to 2.196).

CONCLUSIONS

College students mainly exhibited E-type, and an elevated prevalence of poor sleep quality existed among these students. The E-type was positively associated with poor sleep quality.

Association between behavioral patterns and depression symptoms: dyadic interaction between couples

Background

Behavioral patterns are sometimes associated with depression symptoms; however, few studies have considered the intra-couple effects. This study examined the effect of a spouses' behavioral patterns on depression symptoms within themself and in their spouse.

Methods

A total of 61,118 childbearing age participants (30,559 husband-wife dyads) were surveyed. The depression symptoms were assessed using the nine-item Patient Health Questionnaire (PHQ-9). The behavioral patterns were identified by the latent class analysis. The effects of behavioral patterns on the couple's own depression symptoms (actor effect) and their partner's depression symptoms (partner effect) were analyzed using the Actor-Partner Interdependence Model (APIM).

Results

Three behavioral patterns were identified: low-risk group, moderate-risk group, and high-risk group. The high risk of these behavior patterns would be associated with a higher score on the PHQ-9; for both husbands and wives, their behavioral patterns were positively associated with PHQ-9 scores (βhusband = 0.53, P < 0.01; βwife = 0.58, P < 0.01). Wives' behavioral patterns were also positively associated with their husbands' PHQ-9 scores (β = 0.14, P < 0.01), but husbands' behavioral patterns were not associated with their wives' PHQ-9 scores.

Conclusions

Wives' depression symptoms were affected only by their own behavioral patterns, whereas husbands' depression symptoms were influenced by both their own and their spouses' behavioral patterns.

Healthy sleep patterns and common mental disorders among individuals with cardiovascular disease: A prospective cohort study

BACKGROUND

Sleep behaviors are potentially modifiable risk factors for common mental disorders and cardiovascular disease (CVD). However, the associations between combined sleep behaviors and common mental disorders among individuals with CVD remain unclear.

METHODS

A total of 18,776 participants with a history of CVD from UK Biobank, who were free of depression or anxiety from 2006 to 2010 were included. A composite healthy sleep score was constructed based on five sleep behaviors (chronotype, sleep duration, insomnia, snoring, and excessive daytime sleepiness). Cox proportional hazard regression models were performed to calculate hazard ratios (HRs) and 95 % confidence intervals (CIs) for incident depression and anxiety.

RESULTS

During a median follow-up of 11.8 years, 965 depression and 812 anxiety cases were recorded. The adjusted HRs for participants with a healthy sleep pattern compared with a poor sleep pattern were 0.45 (95 % CI: 0.35-0.57) for depression and 0.77 (95 % CI: 0.58-1.03) for anxiety. There was a linear dose-response association of healthy sleep score with incident depression and anxiety (HR = 0.82, 95 % CI: 0.77-0.87; HR = 0.92, 95 % CI: 0.86-0.99 per 1-score increase, respectively). Likewise, these associations were observed among individuals with coronary heart disease, stroke, heart failure and atrial fibrillation.

CONCLUSIONS

A healthy sleep pattern is significantly associated with a lower risk of depression among individuals with CVD, highlighting the importance of monitoring and improving sleep health in the prevention of common mental disorders among individuals with CVD.

Disparities in greenspace associated with sleep duration among adolescent children in Southern California

More than half of adolescent children do not get the recommended 8 hours of sleep necessary for optimal growth and development. In adults, several studies have evaluated effects of urban stressors including lack of greenspace, air pollution, noise, nighttime light, and psychosocial stress on sleep duration. Little is known about these effects in adolescents, however, it is known that these exposures vary by socioeconomic status (SES). We evaluated the association between several environmental exposures and sleep in adolescent children in Southern California.

Methods

In 2010, a total of 1476 Southern California Children's Health Study (CHS) participants in grades 9 and 10 (mean age, 13.4 years; SD, 0.6) completed a questionnaire including topics on sleep and psychosocial stress. Exposures to greenspace, artificial light at night (ALAN), nighttime noise, and air pollution were estimated at each child's residential address, and SES was characterized by maternal education. Odds ratios and 95% confidence intervals (95% CIs) for sleep outcomes were estimated by environmental exposure, adjusting for age, sex, race/ethnicity, home secondhand smoke, and SES.

Results

An interquartile range (IQR) increase in greenspace decreased the odds of not sleeping at least 8 hours (odds ratio [OR], 0.86 [95% CI, 0.71, 1.05]). This association was significantly protective in low SES participants (OR, 0.77 [95% CI, 0.60, 0.98]) but not for those with high SES (OR, 1.16 [95%CI, 0.80, 1.70]), interaction P = 0.03. Stress mediated 18.4% of the association among low SES participants.

Conclusions

Residing in urban neighborhoods of greater greenness was associated with improved sleep duration among children of low SES but not higher SES. These findings support the importance of widely reported disparities in exposure and access to greenspace in socioeconomically disadvantaged populations.

The Relationship between Sleep, Chronotype, and Dental Caries-A Narrative Review

This article provides an overview of how sleep and circadian rhythm disturbances mutually influence the occurrence of dental caries and how it is possible to reduce the risk of circadian rhythm disturbances, sleep, and associated adverse effects. Dental caries is a global problem worldwide that contributes to sociological limitations. Numerous factors influence the occurrence of dental caries, from socioeconomic factors to cariogenic bacteria, dietary habits, and oral hygiene. However, sleep disorders and circadian rhythm disturbances represent a new approach in the fight against the increasing prevalence of dental caries worldwide. Bacteria in the oral cavity and the oral microbiome are mainly responsible for the development of caries, and saliva plays an important role in their regulation. The circadian rhythm regulates numerous physiological functions, including sleep and saliva production. Disturbances in sleep and circadian rhythms affect saliva production, which impacts the development of dental caries, as saliva is necessary for regulating and maintaining oral health, especially for controlling oral infections. A person's preference for a particular time of day depends on the circadian rhythm called chronotype. Individuals with an evening chronotype have a less healthy lifestyle that can lead to a higher caries risk than individuals with a morning chronotype. Because circadian rhythms are critical to maintaining sleep homeostasis and oral health, sleep disturbances can disrupt circadian rhythms and lead to a vicious cycle.

Association between mobile phone addiction, chronotype and nonsuicidal self-injury among adolescents: A large-scale study in China

BACKGROUND

Nonsuicidal self-injury (NSSI) is a serious public health and clinical problem, particularly for adolescents, and may link to problematic smartphone use (PSU) and chronotype. This study examines the independent and interaction effects of PSU and chronotype on NSSI among adolescents and identified gender differences in these associations.

METHODS

A total of 21,357 students aged 11-19 were recruited using stratified cluster sampling across five representative provinces in China and completed standard questionnaires to record details of PSU, chronotype, and NSSI.

RESULTS

A total of 38.1 % of students reported having engaged in NSSI and 17.7 % had PSU. PSU and chronotype were significantly associated with NSSI among adolescents, and this relationship was stronger in females. Interaction analysis indicated that E-type and PSU were interactively associated with increased risks of NSSI.

CONCLUSION

The findings suggest that E-type and PSU can increase the risk of NSSI both independently and interactively. Therefore, they should be considered in intervention programs for NSSI, especially for females.