Comprehensive assessment of the impact of life habits on sleep disturbance, chronotype, and daytime sleepiness among high-school students

Psychometric adaptation of the Spanish version of the Brief Pittsburgh Sleep Quality Index in adolescents

OBJECTIVE

Good sleep quality is essential for adolescent health, yet sleep difficulties persist in this age group. The 6-item Brief Pittsburgh Sleep Quality Index (B-PSQI) was recently developed to improve sleep quality assessment, however, its validity in adolescents remains unexplored. This study examined the B-PSQI's psychometric properties in Spanish adolescents and adapted the scoring method to age-specific sleep recommendations.

METHODS

A cross-sectional study involving 1,065 adolescents (15-17 years; 56.8% female) was conducted in public high schools. Sleep quality was measured using the B-PSQI, the Insomnia Severity Index (ISI), the short Patient-Reported Outcomes Measurement Information System (PROMIS), and the Epworth Sleepiness Scale (ESS). Additionally, depression and anxiety were assessed using the Depression, Anxiety, and Stress Scales. Reliability, validity, and measurement invariance were analyzed.

RESULTS

The B-PSQI global scores were 4.5 (SD = 1.9) for the original scoring method and 5.4 (SD = 2.8) for the age-adjusted. The age-adjusted B-PSQI showed satisfactory reliability (ω = 0.84) and concurrent, convergent, and discriminant validity (ISI rS = 0.67; PROMIS rS = 0.71; anxiety rS = 0.40; depression rS = 0.42; ESS rS = 0.29). Adequacy for one-factor structure (χ2(4) = 53.9; CFI = 0.97; TLI = 0.92; RMSEA = 0.108; SRMR = 0.05) and invariance across sexes were supported. Both B-PSQI scoring methods showed similar psychometric properties, but the original yielded a higher percentage of poor sleepers (43.1%; cutoff ≥5) than the age-adjusted version (41.9%; cutoff ≥6).

CONCLUSIONS

Findings suggest that the B-PSQI is a valid and reliable measure to assess adolescent sleep quality. Its scoring can be adjusted to provide age-specific criteria for good sleep. The B-PSQI has potential utility for screening sleep problems and facilitating overall health promotion in adolescents.

Moderation by better sleep of the association among childhood maltreatment, neuroticism, and depressive symptoms in the adult volunteers: A moderated mediation model

BACKGROUND

Previously, we demonstrated that childhood maltreatment could worsen depressive symptoms through neuroticism. On the one hand, some studies report that sleep disturbances are related to childhood maltreatment and neuroticism and worsens depressive symptoms. But, to our knowledge, no reports to date have shown the interrelatedness between childhood maltreatment, neuroticism, and depressive symptoms, and sleep disturbance in the one model. We hypothesized that sleep disturbance enhances the influence of maltreatment victimization in childhood or neuroticism on adulthood depressive symptoms and the mediation influence of neuroticism between maltreatment victimization in childhood and adulthood depressive symptoms.

SUBJECTS AND METHODS

Total 584 Japanese volunteer adults recruited through convenience sampling from 4/2017 to 4/2018 were assessed regarding their characteristics of demographics, history of childhood maltreatment, sleep disturbance, neuroticism, and depressive symptoms with questionnaires self-administered. Survey data were analyzed using simple moderation models and a moderating mediation model.

RESULTS

The interaction of sleep disturbance with childhood maltreatment or neuroticism on depressive symptoms was significantly positive. Furthermore, the moderating effect of sleep disturbance on the indirect effect of childhood maltreatment to depressive symptoms through neuroticism was significantly positive.

LIMITATIONS

Because this was a cross-sectional study, a causal relationship could not be confirmed.

CONCLUSIONS

Our findings indicate that individuals with milder sleep disturbance experience fewer depressive symptoms attributable to neuroticism and childhood maltreatment. Additionally, people with less sleep disturbance have fewer depressive symptoms arising from neuroticism owing to childhood maltreatment. Therefore, improvement of sleep disturbance will buffer the aggravating effect of childhood maltreatment, neuroticism caused by various factors, and neuroticism resulting from childhood maltreatment on depressive symptoms.

The effect of circadian timing program for evening-chronotype individuals with obesity on obesity management and sleep quality: A randomized controlled trial

OBJECTIVES

The study aimed to investigate the effect of the circadian timing program (SİZAP) developed for evening-chronotype individuals with obesity on obesity management and sleep quality.

METHODS

This single-site, randomized controlled trial with an experimental research design was registered in ClinicalTrials.gov. It was reported in accordance with the "Consolidated Standards of Reporting Trials" (CONSORT) randomized controlled trial guidelines. The study sample consisted of 38 evening-chronotype individuals with first-degree obesity, with 19 individuals in each study group. The intervention group's sleep hygiene training was conducted and their lifestyle changes were ensured through SİZAP. The control group followed their normal daily lifestyle. No intervention was made in terms of the dietary practices of both groups. Study data were collected using the personal information form, the anthropometric measurement form, the Horne and Ostberg Morning and Evening Questionnaire (MEQ), the Impact of weight on quality of life-lite (IWQOL-lite), the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), the sleep diary, and the data tracked via the website and smart bracelets.

RESULTS

It was determined that the participants in the SİZAP group had a statistically significant decrease in the anthropometric measurements and daytime sleepiness (p < 0.05). The sleep quality scores and the scores of the bodily functions sub-dimension of the quality of life scale were significantly better in the intervention group than in the control group (p < 0.05).

CONCLUSION

It was found that SİZAP is effective in obesity management in evening-chronotype individuals and increases weight loss success and sleep quality.

Longitudinal course and outcome of social jetlag in adolescents: A 1-year follow-up study of the adolescent sleep health epidemiological cohorts

The discrepancy in sleep timing between weekdays and weekends - social jetlag (SJL) - is known to negatively affect student quality of life (QOL). However, the association between social jetlag and physical/mental QOL among adolescents and the precise effect of social jetlag on depressive symptoms and daytime sleepiness remains unknown. This study investigated the longitudinal course, risk factors, and effects of social jetlag, a circadian misalignment, in a school-based cohort. The participants were 427 students (13.3 ± 0.6 years, 45.2% girls) from five junior high schools. We performed a baseline survey in 2019 and a 1-year follow-up survey in 2020. Depressive symptoms, QOL, and daytime sleepiness were assessed using the Birleson Depression Self-Rating Scale for Children, Paediatric Quality of Life Inventory, and Paediatric Daytime Sleepiness Scale. In the baseline survey, 49.6% of the students reported SJL ≥1 h, and 17.1% reported SJL ≥2 h. Among them, 37.2% and 6.8% reported persistent SJL at follow-up, respectively. New incidences of SJL ≥1 h were associated with older age, non-attainment of menarche or voice changes, and longer duration of smartphone use, whereas its persistence was associated with a later chronotype. Persistence of SJL ≥1 h and ≥2 h predicted depressive symptoms and daytime sleepiness at follow-up, whereas new incidences of SJL ≥2 h predicted lower QOL. In conclusion, social jetlag has a persistent course, and daytime functioning can deteriorate as social jetlag becomes chronic. Our findings suggest the need for intensive interventions for social jetlag among adolescents.

Associations of social jetlag with physical activity and sedentary behaviour in children and adolescents: A systematic review and meta-analysis

Sleep and daytime movement behaviours occur co-dependently with each other within a finite 24 h day. Sleep parameters other than sleep duration, such as social jetlag and chronotype, have been linked to health problems and unhealthy behaviours among children and adolescents. Given the increasing number of studies examining sleep timing/chronotype and weight-related behaviours, including physical activity and sedentary behaviour, in the past decade, this systematic review and meta-analysis collated and evaluated the evidence on the relationships of social jetlag and chronotype with physical activity and sedentary behaviour among children and adolescents aged 3-17 years. Seven databases were searched on 16 March 2022, and 52 studies were identified as eligible for inclusion, 47 of which were suitable for the meta-analysis. A positive association was found between social jetlag and screen media use (r = 0.14, 95% CI: 0.04-0.24; I2  = 96%; p = 0.008). The morning chronotype was associated with a higher level of physical activity and a lower level of sedentary behaviour than the evening chronotype. No relationship was found between social jetlag and physical activity. The magnitude of heterogeneity among the included studies was high. Further experimental studies are urgently required to understand how circadian preference or misalignment affects activity behaviours. Interventions to promote an active lifestyle in young populations should consider their circadian preference, especially among individuals with the evening chronotype.

Delayed sleep-wake phase disorder and its related sleep behaviors in the young generation

Delayed sleep-wake phase disorder (DSWPD) is a sleep disorder in which the habitual sleep-wake timing is delayed, resulting in difficulty in falling asleep and waking up at the desired time. Patients with DSWPD frequently experience fatigue, impaired concentration, sleep deprivation during weekdays, and problems of absenteeism, which may be further complicated by depressive symptoms. DSWPD is typically prevalent during adolescence and young adulthood. Although there are no studies comparing internationally, the prevalence of DSWPD is estimated to be approximately 3% with little racial differences between Caucasians and Asians. The presence of this disorder is associated with various physiological, genetic and psychological as well as behavioral factors. Furthermore, social factors are also involved in the mechanism of DSWPD. Recently, delayed sleep phase and prolonged sleep duration in the young generation have been reported during the period of COVID-19 pandemic-related behavioral restrictions. This phenomenon raises a concern about the risk of a mismatch between their sleep-wake phase and social life that may lead to the development of DSWPD after the removal of these restrictions. Although the typical feature of DSWPD is a delay in circadian rhythms, individuals with DSWPD without having misalignment of objectively measured circadian rhythm markers account for approximately 40% of the cases, wherein the psychological and behavioral characteristics of young people, such as truancy and academic or social troubles, are largely involved in the mechanism of this disorder. Recent studies have shown that DSWPD is frequently comorbid with psychiatric disorders, particularly mood and neurodevelopmental disorders, both of which have a bidirectional association with the pathophysiology of DSWPD. Additionally, patients with DSWPD have a strong tendency toward neuroticism and anxiety, which may result in the aggravation of insomnia symptoms. Therefore, future studies should address the effectiveness of cognitive-behavioral approaches in addition to chronobiological approaches in the treatment of DSWPD.

The contribution of self-concept to sleep quality in adolescents: A cross-sectional study

Self-concept has been associated with health-related behaviors and emotional self-regulation, which can improve sleep. However, its involvement in sleep quality in a healthy adolescent population has been little studied. This study evaluated the association between self-concept and sleep quality in adolescents adjusting for sleep/wake habits. The cross-sectional study included 1,751 adolescents, 54% females, with an age of M = 16.76 ± 1.04 years. The information was collected through an electronic survey that contained the Patient Health Questionnaire, Sleep Habits Questionnaire, Pittsburgh Sleep Quality Index, and Self-Concept Scale. A significant association between self-concept, adjustment for adolescents´ characteristics and sleep/wake habits was observed (R² = .17, F = 26.61, p < .001). That is, in addition to the adolescent habits, self-concept also contributed to the explanation of sleep/wake habits. These results reinforce the idea that the self-concept can be an essential factor that contributes to better sleep quality, despite the habits of adolescents.

Association of social jetlag and eating patterns with sleep quality and daytime sleepiness in Japanese high school students

A high prevalence of excessive daytime sleepiness and poor sleep quality has been reported in adolescents, but the effects of social jetlag on sleep quality and daytime sleepiness are unclear. Therefore, we assessed the association of sleep and eating patterns with daytime sleepiness and sleep quality among a total of 756 Japanese high school students. Participants completed the Pittsburgh Sleep Quality Index to evaluate sleep quality, the Pediatric Daytime Sleepiness Scale to evaluate daytime sleepiness, and an 8-day sleep diary. Data on average sleep duration, social jetlag, midsleep on free days sleep corrected, and the differences in the first and last meal timing between school days and non-school days were obtained from participants' sleep diaries. The results reveal that social jetlag is associated with differences in the first meal timing between school days and non-school days, and that social jetlag of more than 2 hr is associated with extremely poor sleep quality and excessive daytime sleepiness in Japanese high school students. Our findings suggest that reducing social jetlag to within a 2-hr window is important to prevent poor sleep quality and excessive daytime sleepiness for this population.

Association between Chronotype and Sleep Quality among Chinese College Students: The Role of Bedtime Procrastination and Sleep Hygiene Awareness

Chronotype and sleep quality have been shown to play significant roles in influencing people's physical and mental health. The current study focuses on examining the relationship between chronotype and sleep quality among Chinese college students and exploring the mediating role of bedtime procrastination and the moderating role of sleep hygiene awareness. A sample of 2822 college students (female = 71.4%) aged between 17 and 29 years (M = 19.77, SD = 1.41) were included and completed the measures of the Pittsburgh Sleep Quality Index (PSQI), Morningness-Eveningness Questionnaire (MEQ), Bedtime Procrastination Scale (BPS) and Sleep Hygiene Awareness Scale (SHAS). The results showed that evening-type students reported the lowest sleep quality and highest levels of bedtime procrastination. In contrast, the highest sleep quality and lowest levels of bedtime procrastination were shown by morning-type, exhibiting the neither-type students' intermediate chronotype. Bedtime procrastination partially mediated the relationship between chronotype and sleep quality. Furthermore, sleep hygiene awareness moderated the direct effect of chronotype on sleep quality and the effect of chronotype in the path from chronotype to bedtime procrastination. Specifically, higher levels of sleep hygiene awareness could buffer the adverse effect of chronotype on self-reported sleep quality but bolstered the negative effect of chronotype on bedtime procrastination. Our results suggest that individuals with an evening preference are inclined to postpone their bedtime and further experience poorer sleep quality at night. Sleep hygiene awareness may serve as a protective factor for poor nocturnal sleep. Overall, the findings highlight the importance of reducing bedtime procrastination and improving sleep hygiene awareness in the interventions designed to help college students to own a better sleep quality, especially for those with evening chronotypes.

Paradoxical association between chronotype and academic achievement: eveningness reduces academic achievement through sleep disturbance and daytime sleepiness

There are conflicting reports about the association between chronotype and academic achievement. Eveningness persons tend to have lower academic achievement, but have higher cognitive abilities. We hypothesized that sleep disturbance and daytime sleepiness, which are known to affect academic achievement, will interact with this association. To investigate the association, a sleep survey and covariance structure analysis was performed on high-school students. Among a total of 344 first-year high-school students, 294 students validly completed the questionnaire. The association between the recent change in their academic achievement, chronotype, daytime sleepiness, and sleep disturbance were analyzed. A simple comparison demonstrated that not chronotype but sleep disturbance and excessive daytime sleepiness were significant associated factors. Chronotype affects academic achievement through sleep disturbance and daytime sleepiness. Chronotype did not have a significant total effect on the reduction in academic achievement, whereas morningness had a significant direct effect and a significant indirect inverse effect through better sleep and less daytime sleepiness. This model accounted for 13.0% of the variance of the reduction in academic achievement. When discussing the association between chronotype and academic achievement, the effect of sleep disturbance and daytime sleepiness should be considered. Reducing sleep disturbance and daytime sleepiness with consideration to the chronotype of each person would be beneficial for the improvement of academic achievement.

Features of Pupils in Each Dinner Habit: Non-late Regular, Regular but Late, and Irregular

Background:

Both late and irregular caloric intakes are becoming common, especially among young adults. This study aimed to investigate features of pupils in Japan following different dinner habits.

Methods:

Dinner habits were categorized into 3 types: non-late regular, regular but late, and irregular. Questionnaires of 2722 pupils in grades 5 to 12 were included, and a multiple comparison test was conducted to investigate the differences of lifestyle factors among the 3 dinner-pattern categories.

Results:

Only half of grade 5 and 6 pupils had non-late regular dinners. The rate of pupils who had regular but late dinners increased from elementary school (11.8%) to senior high school (41.1%) via junior high school (15.1%). More than 30% of pupils took dinner irregularly. The pupils taking non-late regular dinner showed the earliest bedtime and the longest sleep duration among the 3 dinner-time habit categories and also revealed the best academic performance and sleepiness scores. The pupils taking regular but late dinner showed the highest grade, the latest bedtime, the shortest sleep duration, the longest school-day screen time scores, and the worst sleepiness and self-reported academic performance scores. Irregular dinner-takers showed the longest after-school activities.

Conclusions:

Further attention should be given to both late and irregular dinner habits of pupils in terms of supporting their health. Further studies are needed to recommend suitable dinner timings for pupils by assessing optimal levels of variable lifestyle factors, including after-school activity.

Too Jittery to Sleep? Temporal Associations of Actigraphic Sleep and Caffeine in Adolescents

Caffeine consumption has been linked to poor sleep health in adolescents, but it is unknown whether poor sleep predicts caffeine consumption, and/or whether caffeine consumption predicts poor sleep, particularly when sleep is measured objectively. Data were collected from a micro-longitudinal sub-study of the age 15 wave of the Fragile Families and Child Wellbeing Study (n = 589). Adolescents wore an actigraphy device and completed daily surveys for ~1 week. Daily surveys assessed subjective sleep quality and caffeinated beverage consumption (0 = no caffeine, 1 = any caffeine). Separate mixed models assessed whether actigraphy-measured sleep duration, timing, maintenance efficiency, and subjective quality predicted next-day caffeinated beverage consumption within and between adolescents. Variability (standard deviation) of sleep duration and timing, sleep regularity index, and social jetlag were tested as additional between-person predictors. Lagged models tested whether daily caffeinated beverage consumption predicted sleep that night (n = 458). Adolescents with more variable sleep duration and midpoint had higher average odds of consuming caffeinated beverages compared to others. After adolescents consumed ≥1 caffeinated beverage, they had later sleep onset that night and wake time the next morning than usual versus when they did not consume caffeine. Curbing caffeinated beverage consumption may aid in the maintenance of regular sleep schedules and advance sleep timing in adolescents.

Eating habits are associated with subjective sleep quality outcomes among university students: findings of a cross-sectional study

PURPOSE

This study investigated the relationships between eating habits and sleep quality among university students.

METHODS

In a cross-sectional study, university students completed a self-report questionnaire to assess eating habits and meal timing. We assessed subjective sleep quality using the Pittsburgh Sleep Quality Index (PSQI) questionnaire and examined the associations between eating habits and overall sleep quality and its components.

RESULTS

Four hundred ninety-eight students participated in the study. Students who used to skip breakfast, ate late-night snacks, and replaced meals with snacks were at 1.20 times, 1.24 times, and 1.25 times higher likelihood of having poor overall sleep quality, respectively. Multiple logistic regression analysis showed that skipping breakfast (r =  - 0.111, P = 0.007), late-night snacks (r =  - 0.109, P = 0.007), replacing meals with snacks (r =  - 0.126, P = 0.002), and irregular mealtimes (r =  - 0.094, P = 0.018) were the best correlates with poor sleep quality. After adjustment to demographic variables, replacing meals with snacks followed by skipping breakfast were the best independent associations with poor sleep quality by the PSQI.

CONCLUSIONS

Eating habits and meal timing were significantly associated with sleep quality. We speculate that healthy eating habits may lead to improved sleep quality and sleep components among university students.

Relationship Between Big Five Personality Dimensions, Chronotype, and DSM-V Personality Disorders

Morningness-eveningness (M/E) is an important variable in individual differences and has an impact on many areas of life including general and mental health. In previous work eveningness has shown to correlate to personality disorders (PDs) and mental instability such as psychoticism, depression, and bipolar disorders. Therefore, a relationship between M/E and PDs can be assumed but has never been tested. The aim of this study was to assess a possible relationship between DSM-5-PDs and circadian timing (chronotype; M/E). We used the Morningness-Eveningness Stability Scale improved and clock time-based measurements, the PID-5 brief version, and the Big Five brief version. Sample: N = 630; mean age: 27.76 years, SD: 11.36 years; 137 male, 489 female, 4 diverse. In this short screening a relationship between eveningness and DSM-5-personality traits, (evening-oriented participants showing a higher PID-5 score: morningness -0.208/p < 0.001; eveningness: 0.153/p < 0.001) was found. Moreover, participants with high levels of distinctness (fluctuations of the perceived energy level during the day) are prone to PDs too, with distinctness being the best predictor for a high PID-5 score in this sample (0.299/p < 0.001). In the regression analysis, neuroticism, agreeableness, conscientiousness, and extraversion contributed significantly to the model with higher scores on extraversion, agreeableness and conscientiousness being related to lower scores on the PID-5. Neuroticism was positively related to PID-5 scores. Later midpoint of sleep (higher eveningness) was associated with higher PID-5 scores, as were higher fluctuations/amplitude during the day.

A longitudinal investigation of sleep and technology use in early adolescence: does parental control of technology use protect adolescent sleep?

OBJECTIVE

A bi-directional relationship between technology use and adolescent sleep is likely, yet findings are mixed, and it is not known whether parental control of technology use can protect sleep. The current study examined bi-directionality between technology use on school nights and morning/eveningness, sleep duration and daytime sleepiness in early adolescents. We also examined whether time spent using technology mediated the relationship between parental control of technology and adolescent sleep.

METHODS

Adolescents and their primary caregiver (96% mothers) completed questionnaire measures of sleep, technology use and parental control across three, annual waves: Wave 1 (N = 528, M_age = 11.18, SD = 0.56, range = 10-12, 51% male), Wave 2 (N = 502, M_age = 12.19, SD = 0.53, 52% male) and Wave 3 (N = 478, M_age = 13.19, SD = 0.53, 52% male).

RESULTS

When examining the direct relationship between sleep and technology use, cross-lagged panel models showed that time spent using technology predicted shorter sleep duration and greater daytime sleepiness in adolescence, and evening diurnal preference and shorter sleep duration contributed to increased technology use over time. The relationship between technology use and sleep duration was bi-directional. Time spent using technology and adolescent sleep predicted, yet were not predicted by, parental control of technology use.

CONCLUSIONS

While normative changes in sleep (eg, increased eveningness) may promote increased technology use, technology use may further impinge upon sleep. Results suggest it may be pertinent to instead find creative ways in which adolescents themselves can mitigate their risk of inadequate sleep.

Association between eveningness preference, socio-behavioral factors, and insomnia symptoms in Korean adolescents

OBJECTIVE/BACKGROUND

Studies focusing on insomnia in adolescents are relatively scarce compared to those on excessive daytime sleepiness. We aimed to investigate the prevalence of insomnia symptoms and associated factors in Korean high school students.

PATIENTS/METHODS

A total of 8565 students (girls: 4104) were investigated nationwide, across 15 South Korean districts using an online self-report questionnaire. Insomnia symptoms were evaluated using the Global Sleep Assessment Questionnaire. The participants' mean age was 16.77 ± 0.85 years.

RESULTS

The prevalence of insomnia symptoms was 39.43% (n = 3377). Logistic regression was used to estimate the odds ratio (OR) of insomnia symptoms associated with sleep characteristics and social behaviors after adjusting for the relevant covariates. Evening preference (OR, 2.51, 95% CI, 2.20-2.86), perception of insufficient sleep (OR, 3.55, 95% CI, 3.11-4.06), snoring usually/always (OR, 1.25; 95% CI, 1.00-1.55), witnessed sleep apnea usually/always (OR, 1.70; 95% CI, 1.17-2.46), increased internet addiction (OR, 1.02; 95% CI, 1.02-1.03), bad sleep environment (OR, 1.77; 95% CI, 1.50-2.10), ≥3 private extra classes (OR, 1.23; 95% CI, 1.01-1.49), often coffee consumption (OR, 1.31; 95% CI, 1.10-1.56), and often nocturnal eating (OR, 1.24; 95% CI, 1.06-1.45) were associated with insomnia symptoms. Evening preference (OR, 3.48; 95% CI, 2.52-4.82) was also associated with insomnia symptoms in the perceived sufficient sleep subgroup.

CONCLUSION

Insomnia symptoms were common in Korean high school students. Evening preference was the major factor associated with insomnia symptoms. Various socio-behavioral factors were also associated with insomnia symptoms.

Reliability and validity of the Japanese version of the Biological Rhythms Interview of assessment in neuropsychiatry-self report for delayed sleep-wake phase disorder

OBJECTIVE

The Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) might be applicable for assessing delayed sleep-wake phase disorder (DSWPD). We aimed to investigate the reliability and validity of the Japanese version of the BRIAN self-report (J-BRIAN-SR) in DSWPD patients and determine a cutoff score to identify the presence of the disorder.

METHODS

We enrolled 60 newly diagnosed DSWPD outpatients and 64 age-matched healthy controls. We used Cronbach's alpha for internal reliability to evaluate J-BRIAN-SR. We confirmed the reliability of the A test and re-test using Pearson's correlation coefficient in the controls. We used confirmatory factor analysis to evaluate the factor structure of J-BRIAN-SR and referenced the Morningness-Eveningness Questionnaire (MEQ) to check concurrent validity. We analyzed the receiver operating characteristic curve (ROC) to determine the J-BRIAN-SR cutoff point for the presence of DSWPD.

RESULTS

The 18-component scores of the J-BRIAN-SR had an overall reliability coefficient (Cronbach's alpha) of 0.82. We confirmed a high test-retest reliability using an intraclass correlation coefficient (r = 0.84). The correlation between J-BRIAN-SR and MEQ was 0.38 (p = 0.003). The J-BRIAN-SR that we extracted by exploratory factor analysis consisted of three factors. A score of 40 points provided a sensitivity of 80.0% and a specificity of 75.6% for the positivity of DSWPD.

CONCLUSIONS

The results of the present study revealed that J-BRIAN-SR is a valid and reliable instrument for screening and evaluating the severity of DSWPD. Our findings will be useful to physicians and patients in Japan and those in clinical settings.

The association between chronotype and suicidality among students of the medicine and psychology faculties - the mediating role of general mental health indices

The aim of the present study was to evaluate whether anxiety and insomnia symptoms, somatic symptoms, and social dysfunction mediate the link between chronotype and suicidality, as depressive symptoms are known to do, among students of the faculties of Medicine and Psychology. Data from a total of 289 students were eligible for the analysis. The students completed the Suicide Behaviors Questionnaire - Revised, Composite Scale of Morningness, General Health Questionnaire. Single-predictor linear regression models were created to predict suicidality, with a subsequent mediation analysis. A preference toward eveningness was associated with an increase in suicidality Somatic symptoms, anxiety/insomnia, and depressive symptoms fully mediated the relationship between chronotype and suicidality. Depressive symptoms were found to present the strongest effect size of mediation. Social dysfunction was associated with both eveningness and suicidality, but did not play a mediating role. There might be a need to evaluate nonpsychotic mental health indices other than depressive symptoms when assessing the link between suicidality and chronotype among students of the faculties of Medicine and Psychology.

Psychosomatic Stress Responses and Sleep Disturbance Mediate the Effects of Irregular Mealtimes on Presenteeism

BACKGROUND

Presenteeism is the loss of work productivity of workers owing to physical and mental problems, and its socioeconomic effects are greater than those of absenteeism. Presenteeism is caused by psychological and physical dysfunctions. On the other hand, the regularity of mealtimes is an important factor associated with physical and mental health conditions. We hence assessed the association among the irregularity of mealtimes, presenteeism, psychological and physical stress responses, and sleep disturbance in office workers in companies.

METHODS

From May to December 2017, the data of 2905 participants who had given their consent to use their information for academic purposes, and answered a questionnaire about the survey and their lifestyle were collected. Path analysis was performed to analyze the association between the irregularity of mealtimes, psychosomatic symptoms (Brief Job Stress Questionnaire), sleep disturbance (Pittsburgh Sleep Questionnaire), and presenteeism (Work Limitations Questionnaire).

RESULTS

The direct effect of the irregularity of mealtimes on presenteeism was significant but weak. However, the irregularity of mealtimes had a strong effect on presenteeism indirectly through psychological and physical stress responses and sleep disturbance.

CONCLUSION

Psychological and physical stress responses and sleep disturbance were identified as mediating factors of the effects of irregularity of mealtimes on presenteeism.

Poor sleep quality is associated with cardiac autonomic dysfunction in treated hypertensive men

Hypertensives present cardiac autonomic dysfunction. Reduction in sleep quality increases blood pressure (BP) and favors hypertension development. Previous studies suggested a relationship between cardiovascular autonomic dysfunction and sleep quality, but it is unclear whether this association is present in hypertensives. Thus, this study evaluated the relationship between sleep quality and cardiac autonomic modulation in hypertensives. Forty-seven middle-aged hypertensive men under consistent anti-hypertensive treatment were assessed for sleep quality by the Pittsburgh Sleep Quality Index (PSQI-higher score means worse sleep quality). Additionally, their beat-by-beat BP and heart rate (HR) were recorded, and cardiac autonomic modulation was assessed by their variabilities. Mann-Whitney and t tests were used to compare different sleep quality groups: poor (PSQI > 5, n = 24) vs good (PSQI ≤ 5, n = 23), and Spearman's correlations to investigate associations between sleep quality and autonomic markers. Patients with poor sleep quality presented lower cardiac parasympathetic modulation (HR high-frequency band = 26 ± 13 vs 36 ± 15 nu, P = .03; HR total variance = 951 ± 1373 vs 1608 ± 2272 ms2 , P = .05) and cardiac baroreflex sensitivity (4.5 ± 2.3 vs 7.1 ± 3.7 ms/mm Hg, P = .01). Additionally, sleep quality score presented significant positive correlation with HR (r = +0.34, P = .02) and negative correlations with HR high-frequency band (r = -0.34, P = .03), HR total variance (r = -0.35, P = .02), and cardiac baroreflex sensitivity (r = -0.42, P = .01), showing that poor sleep quality is associated with higher HR and lower cardiac parasympathetic modulation and baroreflex sensitivity. In conclusion, in treated hypertensive men, poor sleep quality is associated with cardiac autonomic dysfunction.

Association of sleep disorder with academic performance among medical students in Sudan

Background — Sleep disorder is a common problem amongst medical students. The objective of this study is to determine the association of sleep disorder with academic performances among medical students in Sudan. Methods — A cross-sectional study was conducted in which 199 medical students were selected through simple random sampling techniques. Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale were used to assess the sleep pattern and daytime sleepiness respectively. Logistic regression analysis was used to determine the association of sleep disorder with academic performance. Results — Majority of the students (82.5%) suffered poor sleep quality and 56.5% were suffered from severe day time sleepiness. All the characteristics of sleep quality were associated with poor academic performance but only sleep duration, use of sleep medication, global PSQI score and day time sleepiness were a statistically significant association with poor academic performance. Conclusion — A high prevalence of sleep disorder and its associated with poor academic performance was found in medical students. There is a need for a formulation of policies to address the factors which affect sleep of students.

Which sleep hygiene factors are important? comprehensive assessment of lifestyle habits and job environment on sleep among office workers

BACKGROUND

Although several lifestyle habits are associated with sleep, it is unclear which factors are important. Among office workers, the effect of job environment should also be considered. The multivariate analyses on the effects of lifestyle habits and job environment on sleep among office workers was conducted.

METHODS

A cross-sectional survey of 6,342 employees from 29 companies was conducted in 2017-2019. Complete responses and informed consent were provided by 5,640 participants. The survey examined demographic variables, sleep schedules, Pittsburgh Sleep Quality Index (PSQI), Brief Job Stress Questionnaire (BJSQ), and lifestyle habits.

RESULTS

Mean values were as follows: age, 36.9 years (±10.2); PSQI, 6.52 (±2.83); and total sleep time, 6h06m (±1h40m) on work days and 7h39m (±1h58m) on free days. After adjusting for job environment and demographic variables, irregular meal time (1.45-2.86), not eating vegetables every day (1.35), nightcap (2.74-3.55), weight gain (1.20-1.42), lack of sunlight in the morning in the bedroom (1.48-1.60), waking up before dawn (2.18), electronic display use in bed (1.50), and daily caffeine intake (1.27) were significantly associated with sleep disturbance. Irregular meal time (1.51-2.37), lack of morning breakfast (1.74-2.95), having dinner within 2 hours before bed time (0.49-0.64), not eating vegetables every day (1.52), lack of sunlight exposure in the morning (1.43-2.01), and caffeine use every day (1.42) were also associated with eveningness (p<.01).

CONCLUSION

Each sleep hygiene factor had a different effect size. Sleep hygiene interventions to promote worker sleep health should prioritize factors in accordance with effect size.

Effects of Job Stressors, Stress Response, and Sleep Disturbance on Presenteeism in Office Workers

BACKGROUND

Occupational mental health, work environment, sleep health, presenteeism, and loss of work productivity caused by health problems are all public health concerns. Although sleep affects mental health and presenteeism, the associations between sleep disturbance, job stressors, stress responses, and presenteeism have remained unclear. We hypothesized that job stressors affect the presenteeism of office workers through sleep disturbance and analyzed the association among these factors.

SUBJECTS AND METHODS

In 2017, a cross-sectional survey of adult office workers was performed. A total of 2899 subjects who provided written consent were included in the analysis. The survey collected demographic information, as well as the Work Limitation Questionnaire (WLQ), Pittsburgh Sleep Quality Index (PSQI), and Brief Job Stress Questionnaire (BJSQ). Associations between each of the variables were analyzed by path analysis (covariance structure analysis). This study was approved by the Ethics Committee of Tokyo Medical University.

RESULTS

The path analysis demonstrated that job stressors, psychological and physical stress response (PPSR) in the BJSQ, and sleep disturbance in the PSQI had direct effects on presenteeism in the WLQ. Both job stressors and social support in the BJSQ indirectly affected presenteeism through effects on sleep disturbance and PPSR. Sleep disturbance indirectly affected presenteeism via PPSR. This model accounted for the variation of presenteeism (R ² = 0.322).

CONCLUSION

In the workplace, job stressors and low social support increase presenteeism through psychological and physical stress responses, as well as sleep disturbance. Evaluating and resolving work problems and sleep disturbance would hence be beneficial from the aspects of public health and socioeconomics.

Association of Chronotypes and Sleep Disturbance with Perceived Job Stressors and Stress Response: A Covariance Structure Analysis

BACKGROUND

Chronotype, which is a person's circadian characteristics throughout a day, greatly influences a person's lifestyle, health, and sleep pattern; however, the association between job stress and chronotype remains unknown to date. Therefore, in this study, we analyzed the effects of chronotype on the job stress response, and the mediating effects of sleep disturbance using path analysis.

METHODS

A cross-sectional survey was conducted on 535 adult volunteers (239 men and 296 women; average age, 41.2 ± 11.9 years) from the community. Participants were evaluated using the Diurnal Type Scale for chronotype, Pittsburg Sleep Quality Index for sleep disturbance, Brief Job Stress Questionnaire for job stressors, and the psychological and physical stress response (PPSR). To investigate the association between chronotype, sleep disturbance, perceived job stressors, and PPSR, a covariance structure analysis was performed.

RESULTS

The eveningness chronotype had a significant weak direct effect on sleep disturbance, perceived job stressors, and PPSR, and had a significant indirect effect through sleep disturbance. The perceived job stressors indirectly increased PPSR through sleep disturbance. Sleep disturbance mediated the effects of the eveningness chronotype and perceived job stressors on PPSR. This model accounted for 37.3% of the variability in PPSR of adult workers.

CONCLUSION

Chronotype affected PPSR through sleep disturbance. Therefore, improving the sleep disturbance of workers with the eveningness chronotype may reduce their stress response.

The association between excessive screen-time behaviors and insufficient sleep among adolescents: Findings from the 2017 youth risk behavior surveillance system

Although studies have examined the association between television viewing and poor sleep quality, few studies have considered the association between excessive screen-time behaviors and insufficient sleep among adolescents drawing on a large nationally representative sample. The objective of this study was to examine the association between excessive screen-time behaviors and insufficient sleep among adolescents. Data for this study came from the 2017 Youth Risk Behavior Survey. A sample of 14,603 adolescents aged 14-18 years (51.5% female) was analyzed using logistic regression with insufficient sleep as the outcome variable and excessive screen-time behaviors as the main explanatory variable. Of the 14,603 adolescents, almost three out of four (74.8%) had less than 8 h of sleep on an average school night, and about 43% engaged in excessive screen-time behaviors on an average school day. Controlling for all other predictors, odds were 1.34 times higher for adolescents who engaged in excessive screen-time behaviors to have insufficient sleep when compared to adolescents who did not engage in excessive screen-time behaviors (AOR = 1.34, p < .001, 95% CI = 1.22-1.48). School-based behavior interventions that focus on reduction in excessive screen-time and sedentary behaviors might be beneficial in reducing excessive screen-time behaviors and consequently improve sleep quality among adolescents.

Chronotype: implications for sleep quality in medical students

Medical students who suffer from poor sleep quality may be afflicted by distress. While the change of chronotype may improve sleep quality, few studies have focused on this association. The objective of this study is to analyze the effects of chronotype on sleep quality in medical students while controlling for confounding covariate factors. A cross-sectional survey on sleep quality was conducted among 5497 medical students. Sleep quality, chronotype, and lifestyle were measured according to the Pittsburgh Sleep Quality Index, Morningness-eveningness Questionnaire and Health-promoting Lifestyle Profile. Hierarchical logistic regression was conducted to analyze the influence of various factors, especially chronotype effect on sleep quality. Our results showed that the total score of sleep quality in evening-types was 5.43 ± 2.66, which was significantly higher than that in morning-types (3.88 ± 2.20, P < .001). Morning-type students (OR = 0.40, 95%CI = 0.29-0.55) and intermediate-type students (OR = 0.53, 95%CI = 0.41-0.69) had a lower risk of poor sleep quality compared to evening-types. The strongest predictor of sleep quality was chronotype while controlling for covariates (grade, gender, father's educational level, mother's educational level, internet addiction, mood state, midnight snack frequency, and health-promoting lifestyle profile). Based on the results, we believe that sleep quality among evening-type students may be improved by shifting to keep early hours.

A Mobile Sleep-Management Learning System for Improving Students' Sleeping Habits by Integrating a Self-Regulated Learning Strategy: Randomized Controlled Trial

Background

Insomnia can significantly affect students’ learning performance. Researchers have indicated the importance and challenge of coping with insomnia using nondrug treatments, such as cognitive behavioral therapy (CBT) for insomnia. However, it is easy for the traditional CBT for insomnia to be interrupted owing to the overly lengthy period of sleep therapy. Self-regulated learning (SRL) strategies are known to be an effective approach for helping students improve their time management, as well as their ability to set learning goals and adopt learning strategies.

Objective

The objective of this study was to propose a mobile sleep-management learning system integrated with SRL strategies and CBT.

Methods

A total of 18 undergraduate students from a university in northern Taiwan participated in the 2-week experiment of using this sleep-management system.

Results

The experimental results showed that the proposed approach was useful and easy for students to use. In addition, the number of students with insomnia significantly decreased; that is, the proposed approach could help students improve their sleep quality and cultivate better sleeping habits, which is important for them to enhance their learning efficiency.

Conclusions

With the assistance of this proposed approach, students can plan their daily life by setting goals, applying strategies, monitoring their life habits process, and modifying strategies to cultivate good learning and healthy lifestyle habits.

Trial Registration

Government Research Bulletin MOST104-3011-E038-001; https://www.grb.gov.tw/search/planDetail? id=11568383&docId=467988 (Archived by WebCite at http://www.webcitation.org/73MnPHNri)

The associated risk factors for underweight and overweight high school students in Cambodia

PURPOSE

Overweight and underweight are one of the leading risk factors for non-communicable diseases (NCDs), but little research on this area has been undertaken in Cambodia. Therefore, this study aimed to measure underweight and overweight and their associated risk behaviors among Cambodian high school students.

METHODS

3806 students (mean ag = 15.65 years, SD = 1.80, age range = 11-18 years) from the 2013 Cambodia-Global School-based Student Health Survey were used to yield representative samples of the Cambodian students. Body Mass Index (BMI) was assessed by students' self-reported height and weight. The substance use, depression, eating behaviors, suicidal ideation, and violence were examined as risk factors. The Chi-square and multinomial regressions were performed to assess the relationships between risk factors and BMI.

RESULTS

The prevalence of underweight was 47.4% (N = 1805, Male = 23.3%vs.24.1%) and overweight was 2.3% (N = 89, Male = 1.0%vs.1.3%). The BMI was significantly controlled by age, gender, and body height. Both underweight and overweight students were significantly vulnerable to substance use, feeling depressed, and violent behaviors. Of the risk factors, shortest sleep was prevalent for underweight students while feeling lonely and suicide attempts were the critical risks for overweight students. The daily fruit/vegetable consumption and physical activity were good preventive factors of both underweight and overweight epidemics.

CONCLUSIONS

The risk behaviors of students appear to be strongly associated with underweight and overweight. Interventions targeting these risk behaviors may have the potential to reduce risks. Meanwhile, the preventive strategies should focus on vulnerable students who have poor academic performance, mental health issues and a history of violent experiences.

Sleep quality and its association with psychological distress and sleep hygiene: a cross-sectional study among pre-clinical medical students

Objective:

This study aimed to investigate subjective sleep quality and its association with demographics, psychological health, and sleep hygiene related behaviors in pre-clinical medical students.

Methods:

In this cross-sectional study, a self-administered questionnaire consisting of demographics, sleep hygiene behaviors, Pittsburgh Sleep Quality Index (PSQI), and Depression, Anxiety and Stress Scale-21 (DASS21) was handed out to all medical students of Tehran University of Medical Sciences at pre-clinical stage.

Results:

The questionnaire was filled out by 553 (89.7%) of 616 students approached. About 60% of our sample had a global PSQI score of more than 5 (cut off of poor sleep quality) with mean global PSQI score of 6.32 (SD=2.72). The prevalence of moderate to extremely severe depression, anxiety and stress scores were 26.1%, 29.61%, and 14.5% respectively. Poor sleep quality was associated with later year in the school, psychological distress and several lifestyle behaviors. Constructing a multivariate logistic model, depression, anxiety and some sleep hygiene behaviors were significantly associated with higher PSQI score.

Discussion:

Our findings suggest that poor sleep quality is a common problem among pre-clinical medical students and is associated with some psychological symptoms and sleep hygiene behaviors. This issue demonstrates necessity of interventions to improve the sleep quality in this population group.