Accuracy of self-reported sleep parameters compared with actigraphy in young people with mental ill-health

Influences of Social Disengagement and Depressive Symptoms on Sleep Disturbance in Dementia Caregiving Dyads: A Nationally Representative Study

OBJECTIVES

To examine the influence of social disengagement and depressive symptoms on sleep disturbance among dementia caregiving dyads and the actor-partner interdependence nature of these influences.

DESIGN

Actor-partner interdependence model through structural equation modeling for dyadic analyses.

SETTING AND PARTICIPANTS

A total of 310 dyads of older adults with dementia and their care partners from 2 national representative studies in the United States, the National Health and Aging Trends Study (NHATS) and its companion study, the National Study of Caregiving (NSOC).

METHODS

Data from the NHATS Round 11 and NSOC IV were analyzed using descriptive statistics, Pearson correlation analysis, and the actor-partner interdependence model. Structural equation modeling was used to assess the mediation effects of depressive symptoms within the actor-partner interdependence models.

RESULTS

In the model of caregivers, social disengagement had a direct impact on sleep disturbance (β = 0.49, P < .001) and an indirect impact through depressive symptoms (β = 0.25, P < .001). In the model of older adults with dementia, social disengagement only had an indirect effect on sleep disturbance through depressive symptoms. In models examining partner effects, caregivers' social disengagement directly influenced their care partners' depressive symptoms (β = 0.20, P = .019), which subsequently affected caregivers' sleep disturbance (β = 0.17, P < .001). Social disengagement (β = 0.17, P = .001) and depressive symptoms (β = 0.17, P < .001) in older adults with dementia directly impacted their caregivers' sleep disturbance. Depressive symptoms of older adults with dementia served as multiple mediators linking one member's social disengagement to both their own and partner's sleep.

CONCLUSIONS AND IMPLICATIONS

This study represents one of the first attempts to investigate the influencing mechanism of sleep disturbances among older adults with dementia and their informal caregivers through a dyadic perspective. The sleep disturbance of caregivers may be directly influenced by the social disengagement and depressive symptoms exhibited by both members of the dyad, whereas the sleep disturbance experienced by older adults with dementia can only be indirectly influenced by the dyad's social disengagement via their own depressive symptoms. Dyadic social activities targeting depressive symptoms could be designed to address sleep disturbances in dementia caregiving dyads.

The Integration of Sleep Research Into Eating Disorders Research: Recommendations and Best Practices

OBJECTIVE

Sleep disturbance is common among individuals with eating disorders (EDs), with approximately 50% of patients with EDs reporting sleep disturbance. Sleep problems may promote, exacerbate, or maintain ED symptoms through a variety of hypothesized mechanisms, such as impaired executive function, increased negative affect, and disruptions to appetitive rhythms. Although research investigating the role of sleep in EDs is growing, the current literature suffers from methodological limitations and inconsistencies, which reduce our ability to translate findings to improve clinical practice. The purpose of this forum is to propose a coordinated approach to more seamlessly integrate sleep research into ED research with particular emphasis on best practices in the definition and assessment of sleep characteristics.

METHODS

In this article, we will describe the current status of sleep-related research and relevant gaps within ED research practices, define key sleep characteristics, and review common assessment strategies for these sleep characteristics. Throughout the forum, we also discuss study design considerations and recommendations for future research aiming to integrate sleep research into ED research.

RESULTS/DISCUSSION

Given the potential role of sleep in ED maintenance and treatment, it is important to build upon preliminary findings using a rigorous and systematic approach. Moving forward as a field necessitates a common lens through which future research on sleep and EDs may be conducted, communicated, and evaluated.

Perceived Stress, but Not Rumination, Mediates the Relationship Between Trait Mindfulness and Sleep Quality in Young Adults

Objective

Poor sleep among young adults is prevalent, yet the mediating variables are largely understudied, and there is limited relevant work utilizing objective sleep measures. The present study investigated the mediating effects of perceived stress and rumination in the relationship between trait mindfulness and subjective and objective sleep quality in young adults.

Methods

A total of 170 healthy adults (aged 18-37, M = 20.8, SD = 2.9) self-reported on trait mindfulness, perceived stress, and rumination. The primary (N = 140) and secondary (N = 30) samples both completed the Pittsburgh Sleep Quality Index (PSQI) to assess subjective sleep quality. The secondary sample (N = 30) additionally provided sleep diaries, as well as wrist-worn actigraphy data for assessing objective sleep quality. A mediation analysis was conducted to assess the effect of trait mindfulness on sleep quality with perceived stress and rumination as mediators.

Results

Trait mindfulness was positively associated with better subjective sleep quality; this was fully mediated by perceived stress, b = -0.08, 95% CI [-.12, -0.06]. Rumination was negatively associated with subjective sleep quality but did not mediate the relationship between trait mindfulness and sleep quality, b = -0.01, 95% CI [-.03, 0.02]. Only trait mindfulness was correlated with diary-based sleep ratings, and none of the measures were associated with actigraphy-based sleep quality.

Conclusion

This study indicates that perceived stress is an important mediator in the relationship between trait mindfulness and subjective sleep quality among young adults, rather than rumination. These findings have implications for mindfulness-based therapeutic approaches to address the high prevalence of sleep disorders among young adults, adding mechanistic detail to the literature.

Relationship between insomnia and pain in patients with chronic orofacial pain

OBJECTIVE

Few studies have investigated specific associations between insomnia and orofacial pain (OFP). The aim of this cross-sectional study was to examine relationships of insomnia with pain, mental health, and physical health variables among treatment-seeking patients with chronic OFP.

METHODS

OFP diagnosis, demographics, insomnia symptoms, pain intensity, interference, and duration, mental health measures, and number of medical comorbidities were extracted from the medical records of 450 patients receiving an initial appointment at a university-affiliated tertiary OFP clinic. T-tests compared differences between patients with and without insomnia symptomatology, and between patients with different insomnia subtypes (delayed onset/early wakening).

RESULTS

Compared to patients without insomnia, those with elevated insomnia symptomatology (45.1%) reported higher pain intensity (60.70 ± 20.61 vs 44.15 ± 21.69; P < .001) and interference (43.81 ± 29.84 vs 18.40 ± 23.43; P < 0.001), depression/anxiety symptomatology (5.53 ± 3.32 vs 2.72 ± 2.66; P < 0.001), dissatisfaction with life (21.63 ± 6.95 vs 26.50 ± 6.21; P < .001), and number of medical comorbidities (6.72 ± 5.37 vs 4.37 ± 4.60; P < .001). Patients with Sleep Onset Latency insomnia (SOL-insomnia) (N = 76) reported higher pain intensity (t = 3.57; P < 0.001), and pain interference (t = 4.46; P < .001) compared to those without SOL-insomnia. Those with Early Morning Awakening insomnia (EMA-insomnia) (N = 71) did not significantly differ from those without EMA-insomnia on any of the variables. Differences remained significant after adjusting for age, sex, primary OFP diagnosis, and pain intensity.

CONCLUSIONS

Insomnia is associated with pain outcomes and should be appropriately managed when treating patients with chronic OFP.

Difficulties in emotion regulation moderates the relationship between mood symptoms and nightmares in an inpatient psychiatric sample

BACKGROUND

Emotional processing and regulation of affect are often impaired in psychiatric patients. Nightmares could be considered a manifestation of problems with this process. In the present study, we examined how depression, anxiety and suicidal risk related to difficulties in emotion regulation and nightmares over the course of inpatient treatment. We also explored whether emotion regulation problems moderated the relationship between changes in depression, anxiety, and suicide risk to changes in nightmares from admission to discharge.

METHODS

The present study included 1215 adults admitted to an inpatient psychiatric hospital ranging from 18 to 87 years of age (M = 37.18, SD = 16.14). Mood symptoms, emotion regulation difficulties, nightmares and suicide risk were assessed at admission and discharge. Moderation analyses were calculated using Model 1 of the PROCESS Macro (Hayes, 2013).

RESULTS

Moderation analyses showed the associations between depression and nightmares (b = 0.25, p < .001) and suicide and nightmares (b = 0.34, p < .001) were strongest when patients had high levels of emotion regulation difficulties. Emotion regulation difficulties did not, however, moderate the relationship between anxiety and nightmares. Furthermore, improvement in depression and nightmares was significantly related to improvement in emotion regulation difficulties.

LIMITATIONS

The homogeneity of the sample limits the generalizability of the results. Furthermore, the use of self-report measures, especially sleep related assessments, can bias the data more than objective measures.

CONCLUSIONS

These findings provide clinical implications when treating psychiatric patients such as a need for emotion regulation skills building.

Detecting major depressive disorder presence using passively-collected wearable movement data in a nationally-representative sample

Major Depressive Disorder (MDD) is a heterogeneous disorder, resulting in challenges with early detection. However, changes in sleep and movement patterns may help improve detection. Thus, this study aimed to explore the utility of wrist-worn actigraphy data in combination with machine learning (ML) and deep learning techniques to detect MDD using a commonly used screening method: Patient Health Questionnaire-9 (PHQ-9). Participants (N = 8,378; MDD Screening = 766 participants) completed the and wore Actigraph GT3X+ for one week as part of the National Health and Nutrition Examination Survey (NHANES). Leveraging minute-level, actigraphy data, we evaluated the efficacy of two commonly used ML approaches and identified actigraphy-derived biomarkers indicative of MDD. We employed two ML modeling strategies: (1) a traditional ML approach with theory-driven feature derivation, and (2) a deep learning Convolutional Neural Network (CNN) approach, coupled with gramian angular field transformation. Findings revealed movement-related features to be the most influential in the traditional ML approach and nighttime movement to be the most influential in the CNN approach for detecting MDD. Using a large, nationally-representative sample, this study highlights the potential of using passively-collected, actigraphy data for understanding MDD to better improve diagnosing and treating MDD.

Sleep and childhood maltreatment: A matched-control study of sleep characteristics in Norwegian 16-19-year-olds

Sleep problems are an important but understudied health problem in adolescents exposed to childhood maltreatment. The current study aimed to examine sleep characteristics and insomnia in a population with maltreatment history and compare them to a general population sample of adolescents. Data from a sample of Norwegian 16-19-year-old adolescents with childhood maltreatment experiences (n = 62) were linked to an age- and sex-matched general population sample (n = 238). Independent samples t tests were used to compare the two groups on several detailed sleep parameters, while general linear models were used to control for mental health problems, assessed by the Strengths and Difficulties Questionnaire. Mental health was examined as a potential mediator between childhood maltreatment and sleep characteristics. Adolescents exposed to childhood maltreatment had longer sleep onset latency (1:15 h vs. 47 min, p < 0.001), longer wake after sleep onset (34 min vs. 15 min, p < 0.003), lower sleep efficiency in weekdays (77.8%, vs. 85%, p < 0.007), and lower sleep efficiency in weekends (81.8% vs. 88.9%, p < 0.001) than the reference group. Mental health problems fully mediated the association between childhood maltreatment exposure and longer sleep onset latency and wake after sleep onset. The rate of insomnia did not significantly differ between the groups. This study suggests that older adolescents exposed to childhood maltreatment have more sleep problems than the general adolescent population, and that these problems may be explained by co-existing mental health problems. These findings highlight the potential utility of assessing and providing sleep-focused treatment to adolescents with a history of childhood maltreatment and mental health problems.

Association of time-varying sleep duration and cognitive function with mortality in the elderly: a 12-year community-based cohort study

BACKGROUND

Sleeping problems and cognitive impairment are common in elders. Baseline sleep duration and cognitive status are predictors of mortality. But few studies have explored whether longitudinal changes in sleep duration and cognitive function are related to mortality in older adults. The present study investigated the time-varying relationships of sleep duration and cognitive function with subsequent mortality among community-dwelling elders by using 12 years of repeated-measure data.

METHODS

Taichung Community Health Study for Elders (TCHS-E) is a retrospective, population-based cohort that started in 2009 (wave 1) with a total of 912 elders aged 65 years or above. Follow up was conducted in 2010 (wave 2), 2018 (wave 3), and 2020 (wave 4). Sleep duration and Mini-Mental State Examination (MMSE) forms were executed at baseline and three visits during follow-up. Time-varying Cox proportional hazards regression estimated adjusted hazard ratios (HRs) of mortality with 95% confidence intervals (CIs).

RESULTS

During about 12 years (9,396 person-years) follow-up, 329 deaths from all causes were documented, including 102 deaths due to expanded cardiovascular disease (CVD). In the multivariable-adjusted, time-varying Cox proportional hazard model, the adjusted HR values of all-cause mortality were 1.47 (1.02-2.12) for sleep duration > 9 h/day (vs. 7 h/day) and 1.81 (1.26-2.59) for MMSE < 27 (vs. 30). The adjusted HR values of the expanded CVD mortality were 2.91 (1.24-6.83) for MMSE of 29; 2.69 (1.20-6.05) for MMSE of 27-28; and 4.32 (95% CI: 1.92-9.74) for MMSE < 27. The dose-dependent relationship was significant (p < 0.001). The combinations of sleep duration longer than 9 h/day and MMSE < 27 were linked with the highest risks for expanded CVD and all-cause mortality.

CONCLUSIONS

Long sleep duration and low cognitive function were jointly and independently linked with higher risk of mortality in elders residing in community.

Evaluation of weekend catch-up sleep and weekday sleep duration in relation to metabolic syndrome in Korean adults

PURPOSE

This study aimed to evaluate whether or not the relationship between weekday sleep duration and prevalence of metabolic syndrome (MetS) differs according to weekend catch-up sleep (CUS) in Korean adults.

METHODS

Data from the Korea National Health and Nutrition Examination Survey 2016-2020, including that regarding weekday sleep duration, weekend CUS, MetS components, and confounding factors such as sociodemographic factors, health behaviors, and illness-related factors, were evaluated in Korean adults aged 19 to 80 years. Complex-sample logistic regression was applied after adjusting for confounding factors.

RESULTS

Among 24,313 adults, the prevalence of MetS was lowest in individuals with 6-7 h of sleep on weekdays and CUS ≥ 2 h (17.7%, reference group). The interaction between weekday sleep duration and weekend CUS for MetS was significant. Compared to the reference group, the prevalence of MetS was higher in those who slept < 7 h and had a maximum CUS of 1 h (aORs, 1.42-1.66), and in those who slept ≥ 9 h and had a maximum CUS of 2 h (aORs, 1.28-1.82). In subjects with no CUS or CUS ≥ 2 h, the prevalence of MetS was greater even in those with adequate weekday sleep duration (7- 9 h) than in the reference group (aORs, 1.37 and 1.64, respectively).

CONCLUSION

Weekend CUS may help individuals with short weekday sleep duration reduce their odds of developing MetS, but it may worsen the condition in individuals with a long weekday sleep length.

Opposing brain signatures of sleep in task-based and resting-state conditions

Sleep and depression have a complex, bidirectional relationship, with sleep-associated alterations in brain dynamics and structure impacting a range of symptoms and cognitive abilities. Previous work describing these relationships has provided an incomplete picture by investigating only one or two types of sleep measures, depression, or neuroimaging modalities in parallel. We analyze the correlations between brainwide neural signatures of sleep, cognition, and depression in task and resting-state data from over 30,000 individuals from the UK Biobank and Human Connectome Project. Neural signatures of insomnia and depression are negatively correlated with those of sleep duration measured by accelerometer in the task condition but positively correlated in the resting-state condition. Our results show that resting-state neural signatures of insomnia and depression resemble that of rested wakefulness. This is further supported by our finding of hypoconnectivity in task but hyperconnectivity in resting-state data in association with insomnia and depression. These observations dispute conventional assumptions about the neurofunctional manifestations of hyper- and hypo-somnia, and may explain inconsistent findings in the literature.

Social Isolation, Sleep Disturbance, and Cognitive Functioning (HRS): A Longitudinal Mediation Study

BACKGROUND

Social isolation is prevalent and associated with dementia, yet the directionality and mechanisms are less understood. This study examined the association between social isolation and cognitive functioning and explored the mediating role of sleep disturbance on the social isolation-cognition relationship.

METHODS

Data from 5 753 dementia-free Americans aged ≥50 of 2006 (T1), 2010 (T2), and 2014 (T3) waves of the Health and Retirement Study. Social isolation was measured by the Steptoe Social Isolation Index. Cognitive functioning was measured by the Telephone Interview of Cognitive Status. Sleep disturbance was measured with the modified Jenkins Sleep Scale. We used cross-lagged panel models to determine the associations between social isolation, sleep disturbance, and cognitive functioning.

RESULTS

Social isolation is significantly associated with subsequent cognitive functioning (T1 to T2: β = -0.055, standard error [SE] = 0.014, p < .001; T2 to T3: β = -0.044, SE = 0.016, p < .001). Lower cognitive functioning is significantly associated with greater subsequent social isolation (T1 to T2: β = -0.101, SE = 0.020, p < .001; T2 to T3: β = -0.058, SE = .011, p < .001). Sleep disturbance at T2 partially mediated the effect of social isolation (T1) on cognitive functioning (T3), accounting for 6.2% of the total effect (β = -0.003, SE = 0.001, p < .01).

CONCLUSIONS

Social isolation may deteriorate cognitive functioning and vice versa. The association between social isolation and cognition is partially explained by sleep disturbance.

Sleep duration, weekend catch-up sleep, and risk of obstructive sleep apnea in relation to handgrip strength

PURPOSE

This cross-sectional study aimed to evaluate whether weekday sleep duration, weekend catch-up sleep, and risk of obstructive sleep apnea are individually and in combination associated with handgrip strength.

METHODS

Data from the Korea National Health and Nutrition Examination Survey 2019, including weekday sleep duration, weekend catch-up sleep, STOP-BANG scores, relative handgrip strength (handgrip strength divided by body mass index), and confounding factors (sociodemographic factors, health behaviors, and health and nutritional status), were evaluated in 3678 Korean adults aged 40 to 80 years. Adequate (vs. inadequate) sleep parameters were defined as weekday sleep duration (6-7 vs. ≤ 5 or ≥ 8 h), weekend catch-up sleep (presence vs. absence), and risk of obstructive sleep apnea (low vs. high based on STOP-BANG scores). Sex-specific quintiles of relative handgrip strength were categorized as high (highest 5th quintile) or low (lower 1^st to 4^th quintiles). A complex-sample logistic regression analysis was performed.

RESULTS

After adjusting for other sleep parameters and confounding variables, each adequate sleep parameter individually and collectively was associated with high relative handgrip strength (adjusted odds ratios [95% confidence interval], 1.43 [1.09, 1.89] for 6-7 h weekday sleep duration; 1.44 [1.10, 1.90] for low risk of obstructive sleep apnea; 1.72 [1.23, 2.40] for any two parameters; 1.81 [1.18, 2.79] for all parameters). The combination of adequate weekend catch-up sleep and obstructive sleep apnea risk had the highest odds ratio for high relative handgrip strength (2.36 [1.45, 3.83]).

CONCLUSIONS

Adequate weekday sleep duration, weekend catch-up sleep, and low obstructive sleep apnea risk were individually and in combination associated with high handgrip strength.

Relationship Between Sleep Duration and Metabolic Health in Adolescents

Purpose: This study analyzed the gender differences in the cross-sectional relationship between sleep duration and metabolic health in Korean adolescents. Materials and Methods: Adolescents (1234 males, 1073 females) aged 12-19 years who provided their metabolic syndrome score (MetZscore) and sleep duration were included from the Korea National Health and Nutrition Examination Survey 2016-2020 data. Waist circumference (WC), blood pressure (BP), glucose, triglycerides (TGs), and high-density lipoprotein cholesterol (HDL) were combined to create a standardized MetZscore. Gender-specific linear or quadratic relationships between sleep durations (weekday or difference between weekend and weekday sleep) and MetZscore were analyzed after adjusting for age, family affluence, and self-rated health. Results: Male adolescents displayed an inverse linear relationship between weekday sleep duration and MetZscore [B, -0.037 (confidence interval, 95% CI: -0.054 to -0.019)], whereas females showed a nonsignificant relationship. In male adolescents, the standardized scores of WC, BP, and TG decreased linearly as weekday sleep duration increased. In females, weekday sleep duration had an inverse linear association with WC score and a positive quadratic association with glucose score. MetZscore declined linearly as the difference in sleep durations between weekends and weekdays increased [B, -0.078 (95% CI: -0.123 to -0.034) in males; B, -0.042 (95% CI: -0.080 to -0.005) in females]. Although the scores of WC and HDL in males and the scores of WC and glucose in females had inverse linear relationships with the difference in sleep durations, the BP score in males had a positive quadratic association. Conclusions: According to this study, metabolic health benefited from longer weekend sleep durations than weekdays in both male and female adolescents and longer weekdays sleep durations in male adolescents.

Sleep duration change from childhood to adulthood and adult depressive disorders in the Chinese population

BACKGROUND

Sleep deprivation may cause depressive disorders in both children and adults. However, the effects of sleep duration change from childhood to adulthood on adult depressive disorders are poorly documented. Using the China Family Panel Study (CFPS) data, we aimed to examine the association between sleep duration change from childhood to adulthood and adult depressive disorders in the Chinese population.

METHODS

Data were from 1172 children aged 10-15 years in 2010 who were followed up through 2018 based on the nationally representative and population-based CFPS. According to sleep duration in childhood and early adulthood, the sleep duration change was categorized into four groups: persistently insufficient sleep, sleep duration loss, sleep duration gain and persistently sufficient sleep.

RESULTS

After adjustment for potential covariates, compared with individuals with persistently sufficient sleep duration, those with sleep duration loss (OR = 1.98, 95% CI = 1.14-3.46) and persistently insufficient sleep (OR = 2.35, 95% CI = 1.43-3.88) had higher odds of depressive disorders in adulthood. In contrast, the odds of adult depressive disorders did not significantly increase in those with sleep duration gain (OR = 1.46, 95% CI = 0.88-2.41).

LIMITATIONS

Information on sleep duration was obtained through a questionnaire; the sample size of this study was not large; the generalizality of our findings to other populations should be caucious.

CONCLUSION

Persistently insufficient sleep duration and sleep duration loss from childhood to adulthood were associated with higher odds of adult depressive disorders, while those who were able to change their sleep duration from insufficient status to sufficient status didn't have an increased odds of adult depressive disorders.

Association between self-reported sleep duration and dietary quality in Mexican school-aged children

Short sleep duration has been associated with poor diet quality in school-aged children in multiple populations. However, investigations of sleep and dietary quality in Mexican school-aged children are scarce. The main objective of this work was to assess the association between sleep duration and dietary quality in Mexican school-aged children stratified by sex. The data were collected from 373 (138 girls and 235 boys) elementary school children aged 6-12 years in Monterrey, Nuevo Leon, Mexico. Surveys collected information on general demographic characteristics and self-reported sleep duration. Diet was assessed with 24-h recalls, and dietary quality was calculated by the Healthy Eating Index (HEI-2015). Results indicated that overall mean sleep duration was 8.23 ± 1.06 h. From the total sample, 6.7% slept ≤6 h (not recommended), 55.8% 7-8 h (may be appropriate), and 37.5% ≥ 9 h (recommended). Average total HEI-2015 score was 64.6 (out of possible 100), with boys having lower HEI-2015 scores than girls (57.7 vs 69.4). Moreover, girls and boys with shorter sleep duration (≤6 h compared to ≥ 9 h) had lower HEI-2015 scores (-1.03 [95% CI -2.74, -0.47; p < .01] and -1.78 [95% CI -3.15, -0.86; p < .001], respectively). Regarding the individual components of dietary quality, those with ≤6 h of sleep had lower scores particularly in vegetables, protein sources, added sugars and saturated fats for girls and boys compared to those with ≥9 h. These findings suggest sleep may be an important determinant of dietary practices within the Mexican children.

Effects of Automated Diurnal Variation in Electronic Screen Temperature on Sleep Quality in Young Adults: A Randomized Controlled Trial

OBJECTIVE

Determine whether automated changes in electronic screen color temperature of personal electronic devices is associated with changes in objective and self-reported indices of sleep and mental health in young adults, as well as determine feasibility and acceptability of the experimental manipulation.

PARTICIPANTS

A single-blind randomized controlled trial was conducted at a large public university in the Pacific Northwest region of the United States. Fifty-five participants (female=78%, mean age=19.45 years) who reported using a smartphone and/or laptop computer two hours before bedtime were randomized into either an experimental group (EG; n=29) or active control group (ACG; n=26).

METHODS

Both the EG and ACG had installed on their devices a piece of software that automatically lowers the color temperature of these devices' screens as the day progresses ("f.lux"). However, only the EG had the blue-light-reducing features activated, and participants were blind to condition. Before and after the one-week long experimental manipulation period, participants completed the Pittsburgh Sleep Quality Index (PSQI), Pediatric Daytime Sleepiness Scale (PDSS), Pre-Sleep Arousal Scale (PSAS), and Patient Health Questionnaire (PHQ) and wore an actiwatch for seven consecutive nights.

RESULTS

Participants in the EG did not show greater improvement in objective sleep, self-reported sleep, or mental health compared to participants in the ACG. Participants in the EG rated the software as more distracting and purposely disabled the software more often compared to participants in the ACG.

CONCLUSIONS

Automated diurnal variation in electronic screen temperature in personal devices did not improve sleep or mental health in young adults.

Gait Speed and Sleep Duration Is Associated with Increased Risk of MCI in Older Community-Dwelling Adults

This study aimed to examine the linear and nonlinear associations between sleep duration and gait speed and the risk of developing mild cognitive impairment (MCI) in community-dwelling older adults. Participants were 233 older adults who met the study inclusion criteria. The MCI diagnosis was based on medical evaluations through a clinical interview conducted by a dementia specialist. Self-reported sleep duration was evaluated using the Pittsburgh Sleep Quality Index. The usual gait speed was calculated from the time taken to walk along a 4 m walkway. Multivariate logistic regression analysis was used to calculate the odds ratio (OR) and the 95% confidence interval (95% CI) of developing MCI in relation to sleep duration and gait speed. Generalized additive models were used to examine the dose−response relationships between sleep duration, gait speed, and the risk of developing MCI. Slower gait speed (OR: 1.84, 95%; CI: 1.00−3.13) and poor sleep duration (OR: 1.76, 95%; CI: 1.00−3.35) were associated with the risk of developing MCI, compared with their optimal status. In addition, the combination of poor sleep and slower gait was associated with a higher risk of developing MCI than optimal sleep duration and gait speed (OR: 3.13, 95%; CI: 1.93−5.14). Furthermore, gait speed and sleep duration were non-linearly associated with the risk of developing MCI. These results highlight the complex interplay and synergism between sleep duration and gait abilities on the risk of developing MCI in older adults. In addition, our results suggest that slower gait speed (<1.0 m/s) and short (<330 min) and long (>480 min) sleep duration may be linked to MCI risks through underlying pathways.

Self-reported sleep and exercise patterns in patients admitted with suicidal attempts: a cross-sectional comparative study

BACKGROUND

There is evidence that sleep disturbances and exercise are risk factors for suicide attempts; however, whether sleep disturbances are independently associated with suicide attempts is debatable. We compared the sleep and exercise patterns of individuals who attempted suicide to those of the general population and investigated whether sleep disturbances were independently associated with suicide attempts.

METHODS

Over a year, individuals presented to the emergency department at Hamad General Hospital and Mental Health Services in Doha with suicide attempts (n = 127) filled out questionnaires on sleep and exercise, demographics, and clinical measures. A control group (n = 126) from two primary care centers filled out the same questionnaires during the same period.

RESULTS

Subjects in the suicide group were significantly younger, single, had a lower level of education, and showed considerably more early insomnia, daytime tiredness, interrupted sleep, and no regular exercise. The most common diagnoses seen with suicidality were adjustment disorder and major depression, and the most common method used to attempt suicide was an overdose. After multiple regression analysis, being Arab, belonging to the category "other nationalities," unemployment, and early insomnia were significantly associated with an increased risk of suicide attempts.

CONCLUSION

This is the first comparative study on suicide in the Arabian Gulf. Individuals in Qatar with acute stress, depressive symptoms, sleep disturbances, and lack of exercise are at increased risk of attempting suicide. Thus, clinicians need to routinely screen for sleep and physical activity because of their significant contribution to physical and mental well-being.

Social Jetlag and Other Aspects of Sleep Are Linked to Non-Suicidal Self-Injury Among College Students

INTRODUCTION

Disrupted sleep is associated with non-suicidal self-injury (NSSI) in young adults, but many specific features of sleep continuity and timing have yet to be examined. Additionally, the psychological mechanisms linking sleep to NSSI are unclear. The present study evaluated 14 sleep variables as classifiers of lifetime or recent NSSI and examined potential confounding and mediating factors.

METHODS

A sample of 885 college students provided measures of sleep continuity (e.g., duration, timing, fragmentation), nightmares, insomnia, and perceived sleep control. Lifetime and past 3-month NSSI were measured using a self-report version of the Columbia Suicide Severity Ratings Scale. Bidirectional stepwise regression identified significant sleep classifiers and subsequent models examined their associations with NSSI after adjusting for covariates and through potential psychological mediators.

RESULTS

Only absolute social jetlag was associated with recent NSSI, even after adjusting for covariates, such that each additional hour difference between weekday and weekend sleep schedules was associated with a 17% greater risk of recent NSSI. Nightmares, weekend sleep efficiency, and perceived sleep control were associated with lifetime NSSI, although only weekend sleep efficiency remained associated after adjusting for covariates. Bootstrap mediations identified negative urgency as a partial mediator for recent and lifetime NSSI, and lack of premeditation and perceived burdensomeness as partial mediators for lifetime NSSI.

CONCLUSIONS

The timing and consistency of young adults' sleep schedules may be of greater importance to NSSI among college students than insomnia or insufficient sleep. Future studies of sleep and NSSI should include these measures as potential risk factors. HIGHLIGHTSDifferences between weekday/weekend sleep timing are linked to recent NSSI.Negative urgency partially mediates poor sleep on recent and lifetime NSSI.Sleep shares a multifaceted relationship with NSSI risk in college students.

Concordance between self-reported sleep and actigraphy-assessed sleep in adult survivors of childhood cancer: the impact of psychological and neurocognitive late effects

PURPOSE

To examine self-reported (30-day) sleep versus nightly actigraphy-assessed sleep concordance in long-term survivors of childhood cancer.

METHODS

Four hundred seventy-seven participants enrolled in the St. Jude Lifetime Cohort (53.5% female, median (range) age 34.3 (19.3-61.6) years, 25.4 (10.9-49.3) years from diagnosis) completed the Pittsburgh Sleep Quality Index and ≥ 3 nights of actigraphy. Participants had neurocognitive impairment and/or a self-reported prolonged sleep onset latency (SOL). Self-reported 30-day sleep and nightly actigraphic sleep measures for sleep duration, SOL, and sleep efficiency (SE) were converted into ordinal categories for calculation of weighted kappa coefficients. General linear models estimated associations between measurement concordance and late effects.

RESULTS

Agreements between self-reported and actigraphic measures were slight to fair for sleep duration and SOL measures (kw = 0.20 and kw = 0.22, respectively; p < 0.0001) and poor for SE measures (kw = 0.00, p = 0.79). In multivariable models, severe fatigue and poor sleep quality were significantly associated with greater absolute differences between self-reported and actigraphy-assessed sleep durations (B = 26.6 [p < 0.001] and B = 26.8 [p = 0.01], respectively). Survivors with (versus without) memory impairment had a 44-min higher absolute difference in sleep duration (B = 44.4, p < 0.001). Survivors with, versus without, depression and poor sleep quality had higher absolute discrepancies of SOL (B = 24.5 [p = 0.01] and B = 16.4 [p < 0.0001], respectively). Poor sleep quality was associated with a 12% higher absolute difference in SE (B = 12.32, p < 0.0001).

CONCLUSIONS

Self-reported sleep and actigraphic sleep demonstrated discordance in our sample. Several prevalent late effects were statistically significantly associated with increased measurement discrepancy. Future studies should consider the impacts of late effects on sleep assessment in adult survivors of childhood cancer.

Ecological momentary assessment of mental health in adults at suicide risk: An observational study protocol

AIMS

To describe the research protocol for an ecological momentary assessment (EMA) designed to examine patterns of suicidal ideation and relevant psychosocial stress indicators in adults at risk for suicide.

DESIGN

This observational and longitudinal study will collect data for 28 consecutive days.

METHODS

A total of 150 adults at risk for suicide will be recruited from a single suicide prevention centre and an outpatient clinic in Korea. Self-report questionnaires will be administrated during weeks 0, 1, 3 and 5. Participants will receive text messages three times a day for 4 weeks prompting them to access an online survey link for daily mood survey including depression, anxiety, stress and suicidal ideation. In addition, for the first 2 weeks, they will wear an actigraphy device designed to collect actigraphic data in terms of sleep patterns and physical activity. Data analyses such as descriptive statistics, independent t-tests, one-way ANOVA, chi-squared statistics and time-series and correlation analyses will be performed using IBM SPSS 26.0 and SAS version 9.3. The study received funding from National Research Foundation of Korea in February 2020. Institutional Review Board approval for our study was obtained in April 2021.

DISCUSSIONS

This study will yield fundamental information about daily patterns of suicide ideation and psychosocial stress indicators to develop preventive interventions for adults at risk for suicide.

IMPACT

Our study will contribute to the development of EMAs and interventions for adults at risk for suicide aimed at providing timely and individualized mental health services in a community setting.

TRIAL REGISTRATION

The trial is registered with the Clinical Research Information Service (CRIS). CRIS Registration Number: KCT0006165.

Association Between Sleep and Motoric Cognitive Risk Syndrome Among Community-Dwelling Older Adults: Results From the China Health and Retirement Longitudinal Study

Background: Sleep is increasingly recognized as an important lifestyle contributor to health; however, its relationship with Motoric cognitive risk syndrome (MCR) is still unclear. The present study aimed to examine the associations between sleep duration, sleep quality, and MCR among community-dwelling Chinese older adults.

Methods: We recruited 5,387 participants aged ≥60 years from the China Health and Retirement Longitudinal Study (CHARLS). Sleep-related variables including night sleep duration and sleep quality were assessed via self-reported questionnaires. MCR syndrome was defined as cognitive complaints and slow gait speed without dementia or impaired mobility. Multivariate logistic regression analysis was performed to explore the associations between sleep-related variables and MCR after controlling for all potential confounders including demographic characteristics, lifestyle factors, and comorbidities.

Results: We found that sleep duration was significantly associated with MCR, and the multivariate-adjusted odds ratios (OR) were highest for those with the shortest (<6 h OR = 1.55, 95% CI = 1.18–2.04) and longest (≥10 h OR = 1.73, 95% CI = 1.03–2.91) sleep durations. Moreover, an increasing frequency of self-perceived poor sleep quality was significantly associated with MCR in the adjusted model (3–4 days OR = 1.58, 95% CI = 1.16–2.17; 5–7 days OR = 1.81, 95% CI = 1.37–2.40).

Conclusions: Our study indicated an inverted U-shaped association between night sleep duration and MCR. Poor sleep quality was also associated with higher odds of MCR in community-dwelling Chinese elders. Longitudinal studies with a larger population size are needed to establish causality in the future and further explore potential action mechanisms.

Poor sleep is associated with small hippocampal subfields in cognitively normal elderly individuals

Recent studies demonstrated reduced hippocampal volumes in elderly healthy individuals who are cognitively normal but poor sleepers. The association between sleep quality and the pattern of volume loss across hippocampal subfields (HSs) is not well known. Thus, it is the focus of the present study. Sleep quality was self-assessed using the Pittsburgh Sleep Quality Index (PSQI). The HS volumes were measured using sub-millimetre in-plane resolution T2-weighted magnetic resonance imaging data. A total of 67 cognitively normal elderly individuals aged 60-83 years were classified into 30 normal sleepers with a PSQI <5 and 37 poor sleepers with a PSQI ≥5. The two groups were equivalent in age, gender distribution, ethnicity, education attainment, handedness and cognitive performance. Compared to normal sleepers, poor sleepers exhibited significantly lower normalised volumes in the left cornu ammonis field 1 (CA1), dentate gyrus (DG) and subiculum. In contrast, there were no significant differences in normalised grey and white matter volumes between the two groups. The global PSQI was negatively associated with the normalised volumes of the left CA1, DG and subiculum. Sleep duration was associated with the normalised volumes of the bilateral CA1, DG, left CA2 and subiculum. Verbal memory scores were associated with the left CA1 volume. In conclusion, poor sleep quality, especially insufficient sleep duration, was associated with volume loss in several HSs that are involved in specific learning and memory tasks. As the hippocampus does not regulate sleep, it is more likely that poor sleep leads to small hippocampi. Thus, based on this assumption, improving sleep quality of poor sleeper elderly individuals could benefit hippocampal health.

Shared genetic architecture underlying sleep and weight in children

Meta-analyses suggest shorter sleep as a risk factor for obesity in children. The prevailing hypothesis is that shorter sleep causes obesity by impacting homeostatic processes. Sleep duration and adiposity are both heritable, and the association may reflect shared genetic aetiology. We examined the association between a body mass index (BMI) genetic risk score (GRS) and objectively-measured total sleep time (TST) in a cohort of Norwegian children (enrolled at age four in 2007-2008) using cross-sectional data at age six. The analytical sample included 452 six-year old children with complete genotype and phenotype data. The outcome was actigraphic total sleep time (TST) measured at age six years. Genetic risk of obesity was inferred using a 32-single nucleotide polymorphism (SNP) weighted GRS of BMI. Covariates were BMI-Standard deviation scores (SDS) (which takes into account age and sex) and, in a sensitivity analysis socioeconomic status. Analyses consisted of Pearson's correlations and linear regressions. In our sample, 54% of participants were male; mean (SD) TST, age and BMI were 9.6 (0.8) hours, 6.0 (0.2) years and 15.3 (1.2) kg/m², respectively. BMI and TST were not correlated, r = -0.003, p = 0.946. However, the BMI GRS was associated with TST after adjusting for BMI-SDS, standardised β = -0.11; 95% confidence interval (CI) = -0.22, -0.01. To our knowledge, this is the first study to establish a relationship between genetic risk of obesity and objective sleep duration in children. Findings suggest some shared genetic aetiology underlying these traits. Future research could identify the common biological pathways through which common genes predispose to both shorter sleep and increased risk of obesity.

Sleep quality relates to emotional reactivity via intracortical myelination

A good quality and amount of sleep are fundamental to preserve cognition and affect. New evidence also indicates that poor sleep is detrimental to brain myelination. In this study, we test the hypothesis that sleep quality and/or quantity relate to variability in cognitive and emotional function via the mediating effect of interindividual differences in proxy neuroimaging measures of white matter integrity and intracortical myelination. By employing a demographically and neuropsychologically well-characterized sample of healthy people drawn from the Human Connectome Project (n = 974), we found that quality and amount of sleep were only marginally linked to cognitive performance. In contrast, poor quality and short sleep increased negative affect (i.e. anger, fear, and perceived stress) and reduced life satisfaction and positive emotionality. At the brain level, poorer sleep quality and shorter sleep duration related to lower intracortical myelin in the mid-posterior cingulate cortex (p = 0.038), middle temporal cortex (p = 0.024), and anterior orbitofrontal cortex (OFC, p = 0.034) but did not significantly affect different measures of white matter integrity. Finally, lower intracortical myelin in the OFC mediated the association between poor sleep quality and negative emotionality (p < 0.05). We conclude that intracortical myelination is an important mediator of the negative consequences of poor sleep on affective behavior.

Self-reported sleep relates to hippocampal atrophy across the adult lifespan: results from the Lifebrain consortium

Objectives

Poor sleep is associated with multiple age-related neurodegenerative and neuropsychiatric conditions. The hippocampus plays a special role in sleep and sleep-dependent cognition, and accelerated hippocampal atrophy is typically seen with higher age. Hence, it is critical to establish how the relationship between sleep and hippocampal volume loss unfolds across the adult lifespan.

Methods

Self-reported sleep measures and MRI-derived hippocampal volumes were obtained from 3105 cognitively normal participants (18–90 years) from major European brain studies in the Lifebrain consortium. Hippocampal volume change was estimated from 5116 MRIs from 1299 participants for whom longitudinal MRIs were available, followed up to 11 years with a mean interval of 3.3 years. Cross-sectional analyses were repeated in a sample of 21,390 participants from the UK Biobank.

Results

No cross-sectional sleep—hippocampal volume relationships were found. However, worse sleep quality, efficiency, problems, and daytime tiredness were related to greater hippocampal volume loss over time, with high scorers showing 0.22% greater annual loss than low scorers. The relationship between sleep and hippocampal atrophy did not vary across age. Simulations showed that the observed longitudinal effects were too small to be detected as age-interactions in the cross-sectional analyses.

Conclusions

Worse self-reported sleep is associated with higher rates of hippocampal volume decline across the adult lifespan. This suggests that sleep is relevant to understand individual differences in hippocampal atrophy, but limited effect sizes call for cautious interpretation.

Associations Between Transgender Identity, Sleep, Mental Health and Suicidality Among a North American Cohort of College Students

PURPOSE

The purpose of this study is to examine the associations between transgender identity, sleep, and mental health among a North American cohort of cisgender and transgender college students.

PARTICIPANTS AND METHODS

This cross-sectional study surveyed 221,549 North American college students from the 2016-2017 American College Health Association-National College Health Assessment II. Bivariate and multivariable analysis examined associations among transgender identity and outcomes of insomnia symptoms, daytime sleepiness, sleep disorder diagnoses and treatments. Mental health outcomes included mood symptoms, suicidal behaviors, anxiety and depression diagnoses and treatments.

RESULTS

Transgender identity was reported by 1.6% (n=3471) of United States (US) and 1.7% (n=717) Canadian students, respectively. Mean age was 22.5 ±6. Transgender college students have an increased prevalence of daytime sleepiness, insomnia symptoms, diagnoses and/or treatment of insomnia and other sleep disorders as compared to cisgender college students. Mental Health symptoms are more prevalent with a 2-fold increase in depression and anxiety and nearly a 4-fold increase in suicide attempts among transgender students. A higher burden of mood symptoms exists among transgender college students in the US in comparison to Canadian students.

CONCLUSION

Transgender college students have an alarmingly high rate of mood, sleep disturbances and sleep diagnoses, and suicidality. Colleges and universities must provide sufficient resources to address the sleep and mental health needs of transgender students. Institutions must adopt gender affirming policies that promote an inclusive environment. Increased allocation of resources and adoption of policies that enhance the physical and mental health of transgender students could improve sleep, mood, and potentially lower the suicide risk among a population that often experiences health inequities.

How do associations between sleep duration and metabolic health differ with age in the UK general population?

BACKGROUND

Despite a growing body of evidence suggesting that short sleep duration may be linked to adverse metabolic outcomes, how these associations differ between age groups remains unclear. We use eight years of data from the UK National Diet and Nutritional Survey (NDNS) (2008-2016) to analyse cross-sectional relationships between sleep duration and metabolic risk in participants aged 11-70 years.

METHODS

Participants (n = 2008) who provided both metabolic risk and sleep duration data were included. Self-reported sleep duration was standardised by age, to account for differences in age-related sleep requirements. A standardised metabolic risk score was constructed, comprising: waist circumference, blood pressure, serum triglycerides, serum high-density lipoprotein cholesterol, and fasting plasma glucose. Regression models were constructed across four age groups from adolescents to older adults.

RESULTS

Overall, decreased sleep duration (hrs) was associated with an increased metabolic risk (standard deviations) with significant quadratic (B:0.028 [95%CI: 0.007, 0.050]) and linear (B:-0.061 [95%CI: -0.111, -0.011]) sleep duration coefficients. When separated by age group, stronger associations were seen among mid-aged adults (36-50y) (quadratic coefficient: 0.038 [95%CI: 0.002, 0.074]) compared to other age groups (e.g. adolescents (11-18y), quadratic coefficient: -0.009 [95%CI: -0.042, 0.025]). An increased difference between weekend and weekday sleep was only associated with increased metabolic risk in adults aged 51-70 years (B:0.18 [95%CI: 0.005, 0.348]).

CONCLUSIONS

Our results indicate that sleep duration is linked to adverse metabolic risk and suggest heterogeneity between age groups. Longitudinal studies with larger sample sizes are required to explore long-term effects of abnormal sleep and potential remedial benefits.

Lifestyle habits and academy performance amongst forcibly displaced students: A cross-sectional survey in a school of dentistry

INTRODUCTION

There is no recognised investigation examining the influence of some lifestyle comportments on academic performance (AP) in forcibly displaced students in higher education. Thus, the frequency of physical inactivity (PI), insufficient sleep (IS), alcohol consumption (AC), drug consumption (DC) and cigarette smoking (CS) and the independent and combined consequences of these habits on AP in forcibly displaced dental students were investigated.

MATERIALS AND METHODS

A sample of 185 students was studied (thirty-seven forcibly displaced and 148 non-displaced students). This cross-sectional study used an institutional administrative database that included students' demographic features and lifestyle behaviours. Multivariate analyses were performed to evaluate the independent and combined effects of lifestyle behaviours on AP.

RESULTS

PI, IS, AC, DC and CS were observed in 51%, 43%, 83%, 27% and 16% of forcibly displaced students, respectively. Compared with non-displaced students, forcibly displaced students presented higher frequencies for all of these behaviours (P < .05), lower AP (P < .0001) and lower socio-economic status (P = .003). Unadjusted regression models showed independent and significant associations between forcibly displaced students and PI (P = .01), IS (P = .01), AC (P = .01), DC (P < .0001), CS (P = .02) and low AP (P = .006). The multivariate model for AP and forcibly displaced students increased odds by 4.6 times (1.5-11; 95% CI). Moreover, the lifestyle comportments studied were also statistically significant, showing combined effects. The variables of gender and age were not statistically significant in the adjusted model.

CONCLUSIONS

This research observed high frequencies of the behaviours analysed in forcibly displaced students. Furthermore, independent and combined effects of them on AP were detected.

Within-person fluctuations in stressful life events, sleep, and anxiety and depression symptoms during adolescence: a multiwave prospective study

BACKGROUND

Adolescence is characterized by substantial changes in sleep behavior, heightened exposure to stressful life events (SLEs), and elevated risk for internalizing problems like anxiety and depression. Although SLEs are consistently associated with the onset of internalizing psychopathology, the mechanisms underlying this relationship remain poorly understood, especially at the within-person level. Here, we leverage a high-frequency longitudinal design to examine sleep as a potential mechanism linking SLEs to increases in anxiety and depression symptoms over a one-year period.

METHODS

Thirty female adolescents aged 15-17 years completed 12 monthly in-laboratory assessments of exposure to SLEs and symptoms of anxiety and depression (n = 355 monthly assessments), and wore an actigraphy wristband for continuous monitoring of sleep for the duration of the study (n = 6,824 sleep days). Multilevel models examined concurrent and lagged within-person associations between SLEs, sleep duration and timing regularity, and anxiety and depression symptoms.

RESULTS

Within-person fluctuations in SLEs were associated with variability in sleep duration both concurrently and prospectively, such that when adolescents experienced greater SLEs than was typical for them, they exhibited more variable sleep duration that same month as well as the following month. In turn, within-person increases in sleep duration variability predicted greater anxiety symptoms in the same month and mediated the association between SLEs and anxiety.

CONCLUSIONS

These findings highlight sleep disruptions as a mechanism underlying the longitudinal associations between SLEs and anxiety symptoms, and suggest that interventions promoting sleep schedule consistency may help mitigate risk for stress-related psychopathology in adolescence.

Subjective and objective sleep among air ambulance personnel

The present study aimed to investigate the effects of shift work on sleep among pilots and Helicopter Emergency Medical Service crew members (HCM) in the Norwegian Air Ambulance. Sleep was assessed by diaries and actigraphy during a workweek (24 h duty for 7 consecutive days) in the winter season and a workweek during the summer season in pilots and HCM (N = 50). Additionally, differences in sleep were studied between the week before work, the workweek, and the week after work in both seasons. Results indicated that bedtime was later (p <.001) and time spent in bed (p <.05) was shorter during the summer, compared to the winter, season. The workers delayed the sleep period in the workweek, compared to the week before (winter: p <.001, summer: p <.001) and the week after (winter: p <.05-.001, summer: p <.001). They spent more time in bed during the workweek, compared to the week before (winter: p <.001, summer: p <.01) and after (winter: p <.001, summer: p =.37). Further, the workers had longer wake after sleep onset during the workweek, compared to the week before (winter: p <.001, summer: p <.01) and the week after (winter: p <.01, summer: p <.01). Finally, the workers had lower sleep efficiency during the workweek recorded by actigraphy compared to the week before (winter: p <.01, summer: p <.001) and the week after (winter: p <.01, summer: p <.001). According to the sleep diaries the total sleep time was 7:17 h in the winter and 7:03 h in the summer season. Overall, the sleep was somewhat affected during the workweek, with delayed sleep period, longer wake after sleep onset, and lower sleep efficiency compared to when off work. However, the workers spent more time in bed during the workweek compared to the weeks off, and they obtained over 7 h of sleep in both workweeks. Our findings suggest that the pilots and the HCM sleep well during the workweek, although it affected their sleep to some extent.

Sleep duration trajectories from adolescence to emerging adulthood: Findings from a population-based birth cohort

This study aimed to describe longitudinal trajectories of sleep duration, among adolescents and adults from the Pelotas (Brazil) 1993 Birth Cohort, as well as characterize different trajectories groups according to socioeconomic, demographic and behavior characteristics. Sleep duration, hours per day (from Monday to Friday), bedtime and wake-up time were self-reported by participants at ages 11, 18 and 22 years. Covariables included socioeconomic, demographic, health and behavior characteristics. Trajectory analysis was performed using a semi-parametric, group-based modelling approach. Prevalence and 95% confidence interval were obtained to describe covariables and sleep trajectory groups. Chi-square test was employed in statistical analysis and all analyses were stratified by sex. A total of 3.395 individuals were included in the analysis. In both sexes, bedtime became later across years, while wake-up time presented little variation. Differences according sex were more pronounced from 18 years onwards. Three trajectories of sleep duration from 11 to 22 years were identified for males: "increase and maintenance" (3.4%), "fast reduction and maintenance" (45.0%) and "constant reduction" (51.6%). While in females the trajectories identified were: "increase and decrease" (2.4%), "fast reduction and maintenance" (25.6%) and "constant reduction" (72.0%). Men and women who belong to trajectories with longer sleep durations were more likely to present higher percentages of some risk behaviors and poor socioeconomic condition. Our results have provided longitudinal information regarding sleep duration trajectories in a medium-sized city in Brazil, aiming at filling an existing gap in literature from low- and middle-income countries.

Measuring sleep duration in adolescence: Comparing subjective and objective daily methods

OBJECTIVES

This study provides the first investigation into the correspondence between self-reported and actigraph-measured nighttime sleep duration in adolescents that disambiguates between- versus within-person associations. Moderators were evaluated to determine if between- and within-person correspondence vary by participant characteristics.

METHODS

One hundred fifty adolescents (14-21 years) reported sleep time for 1 week, while wearing an actigraph, and reported on moderators, including demographics (i.e., sex, age, ethnicity, and socioeconomic status), depressive symptoms, and perceived stress. Mixed effects models evaluated within- and between-person associations between self-reported and actigraph-measured sleep, and examined whether these associations differed by possible moderators.

RESULTS

Results indicated significant between- (b = 0.77, SE = 0.08, P < .001) and within-person (b = 0.51, SE = 0.04, P < .001) associations between self-reported and actigraph-measured sleep duration, with no significant moderation effects.

CONCLUSIONS

Our results support the use of either self-reports or actigraphs to examine within-person nighttime sleep duration in adolescent community samples.

Sleep duration patterns from adolescence to young adulthood and the risk of asthma

PURPOSE

This study examined the association between sleep duration trajectories from adolescence to young adulthood and the risk of asthma into young adulthood.

METHODS

Using data from 10,362 participants in the National Longitudinal Study of Adolescent to Adult Health (Add Health) free of asthma at baseline, we constructed trajectories of sleep duration from adolescence (age 13-18 years) to young adulthood (age 24-32 years) and used them to examine the association between sleep duration patterns and the risk of new-onset asthma using a log-binomial regression model after adjusting for potential confounders.

RESULTS

The results revealed that 14.4% of nonasthmatic participants had persistent short sleep duration, whereas 80.0% had adequate sleep duration from adolescence through young adulthood. Consistently short-sleepers had 1.52 times the risk of new-onset asthma by age 32 years (95% CI 1.11, 2.10) compared with consistently adequate sleepers. The association was stronger in those with a family history of asthma (aRR = 2.43, 95% CI 1.15, 5.13) than in those without such history (aRR = 1.43, 95% CI 1.05, 1.95).

CONCLUSIONS

We conclude that persistent short sleep duration is associated with an increased risk of new-onset asthma in young adults. This association may be more pronounced among those at high risk of asthma because of family history.

Relationship between insomnia and depression in a community sample depends on habitual sleep duration

Sleep disturbances, such as short sleep duration and insomnia, are core features of depression. However, it is unclear if sleep duration and insomnia have an interactive effect on depression severity or individual symptoms. Data were drawn from a community sample (N = 1007) containing responses on the Insomnia Severity Index, Patient Health Questionnaire-9 (PHQ-9), and average sleep duration. Regression analyses determined the prevalence risks (PR) of symptoms of depression based on insomnia severity and sleep duration. Depression severity was related to insomnia severity (PR 1.09, p < 0.001) and short sleep duration (PR 1.52, p < 0.001), but the interaction between the two was negative (PR 0.97, p < 0.001). Insomnia severity increased the prevalence risk of all individual depression symptoms between 8 and 15%, while sleep duration increased the prevalence risk of appetite dysregulation (PR 1.86, p < 0.001), fatigue (PR 1.51, p < 0.001), difficulty concentrating (PR 1.61, p = 0.003), feelings of failure (PR 1.58, p = 0.002), and suicidal behavior (PR 2.54, p = 0.01). The interaction of sleep duration and insomnia was negative and ranged between 3 and 6%. In clinically significant depression (PHQ >=10), only insomnia severity increased the prevalence risk of depression severity (PR 1.02, p = 0.001). Insomnia and short sleep predict prevalent depression, but their interactive effect was negative. Thus, while insomnia had a greater association with depression severity and symptoms, this association was dependent on habitual sleep duration.

Lucid Dreaming, Nightmares, and Sleep Paralysis: Associations With Reality Testing Deficits and Paranormal Experience/Belief

Focusing on lucid dreaming, this paper examined relationships between dissociated experiences related to rapid eye movement (REM) sleep (lucid dreaming, nightmares, and sleep paralysis), reality testing, and paranormal experiences/beliefs. The study comprised a UK-based online sample of 455 respondents (110 males, 345 females, Mean age = 34.46 years, SD = 15.70), who had all previously experienced lucid dreaming. Respondents completed established self-report measures assessing control within lucid dreaming, experience and frequency of nightmares, incidence of sleep paralysis, proneness to reality testing deficits (Inventory of Personality Organization subscale, IPO-RT), subjective experience of receptive psi and life after death (paranormal experience), and paranormal belief. Analysis comprised tests of correlational and predictive relationships between sleep-related outcomes, IPO-RT scores, and paranormal measures. Significant positive correlations between sleep and paranormal measures were weak. Paranormal measures related differentially to sleep indices. Paranormal experience correlated with lucid dreaming, nightmares, and sleep paralysis, whereas paranormal belief related only to nightmares and sleep paralysis. IPO-RT correlated positively with all paranormal and sleep-related measures. Within the IPO-RT, the Auditory and Visual Hallucinations sub-factor demonstrated the strongest positive associations with sleep measures. Structural equation modeling indicated that Auditory and Visual Hallucinations significantly positively predicted dissociated experiences related to REM sleep, while paranormal experience did not. However, paranormal experience was a significant predictor when analysis controlled for Auditory and Visual Hallucinations. The moderate positive association between these variables explained this effect. Findings indicated that self-generated, productive cognitive-processes (as encompassed by Auditory and Visual Hallucinations) played a significant role in conscious control and awareness of lucid dreaming, and related dissociative sleep states (sleep paralysis and nightmares).

Longitudinal Change in Adolescent Bedtimes Measured by Self-Report and Actigraphy

Introduction:

Sleep is often quantified using self-report or actigraphy. Self-report is practical and less technically challenging, but prone to bias. We sought to determine whether these methods have comparable sensitivity to measure longitudinal changes in adolescent bedtimes.

Methods:

We measured one week of free-living sleep with wrist actigraphy and usual bedtime on school nights and non-school nights with self-report questionnaire in 144 students at 15 y and 17 y.

Results:

Self-reported and actigraphy-measured bedtimes were correlated with one another at 15 y and 17 y (p < .001), but reported bedtime was consistently earlier (>30 minutes, p < .001) and with wide inter-method confidence intervals (> ±106 minutes). Mean inter-method discrepancy did not differ on school nights at 15 y and 17 y but was greater at 17 y on non-school nights (p = .002). Inter-method discrepancy at 15 y was not correlated to that at 17 y. Mean change in self-reported school night bedtime from 15 y to 17 y did not differ from that by actigraphy, but self-reported bedtime changed less on non-school nights (p = .002). Two-year changes in self-reported bedtime did not correlate with changes measured by actigraphy.

Conclusions:

Although methods were correlated, consistently earlier self-reported bedtime suggests report-bias. More varied non-school night bedtimes challenge the accuracy of self-report and actigraphy, reducing sensitivity to change. On school nights, the methods did not differ in group-level sensitivity to changes in bedtime. However, lack of correlation between bedtime changes by each method suggests sensitivity to individual-level change was different. Methodological differences in sensitivity to individual- and group-level change should be considered in longitudinal studies of adolescent sleep patterns.

The Association Between Body Mass Index (BMI) and Sleep Duration: Where Are We after nearly Two Decades of Epidemiological Research?

Over the past twenty years we have seen a vast number of epidemiological studies emerge on the topic of obesity and sleep duration, with a focus on body mass index, as it is easy and cheap to measure and analyse. Such studies largely observe that cross-sectionally a higher BMI is associated with shorter sleep and that in longitudinal studies shorter sleep duration is associated with increases in BMI over time, but some research has found no relationship between the two. This narrative review is not exhaustive, but appraises the literature on sleep duration and BMI from perspectives that have previously been unexplored in a single paper. As such, I discuss research in these important areas: bidirectionality, objective vs. subjective sleep duration, how meaningful the effect sizes are and how we have begun to address causality in this area. From the evidence appraised in this review, it is clear that: (i) there is some modest evidence of a bidirectional relationship between BMI and sleep duration in both children and adults; (ii) objective measurements of sleep should be used where possible; (iii) it remains difficult to confirm whether the effect sizes are conclusively meaningful in a clinical setting, but at least in adults this so far seems unlikely; (iv) to date, there is no solid evidence that this relationship (in either direction) is in fact causal. In the near future, I would like to see triangulation of these findings and perhaps a move towards focusing on distinct aspects of the relationship between obesity and sleep that have not previously been addressed in detail, for various reasons.

The association of sleep with metabolic pathways and metabolites: evidence from the Dietary Approaches to Stop Hypertension (DASH)-sodium feeding study

INTRODUCTION

Sleep is increasingly being viewed as an issue of public health concern, yet few epidemiologic studies have explored associations between sleep habits and metabolomic profile.

OBJECTIVES

To assess the association between sleep and blood metabolites.

METHODS

We examined the association between sleep and 891 fasting plasma metabolites in a subgroup of 106 participants from the Dietary Approaches to Stop Hypertension (DASH)-Sodium feeding trial (1997-1999). We produced two sleep variables to analyze, sleep midpoint (median time between bedtime and waketime) and sleep duration, as well as bedtime and wake time. Metabolites were measured using liquid and gas chromatography, coupled with mass spectrometry. We assessed associations between sleep variables and log transformed metabolites using linear mixed-effects models. We combined the resulting p-values using Fisher's method to calculate associations between sleep and 38 metabolic pathways.

RESULTS

Sixteen pathways were associated (p < 0.05) with midpoint. Only the γ-glutamyl amino acid metabolism pathway reached Bonferroni-corrected threshold (0.0013). Eighty-three metabolites were associated with midpoint (FDR < 0.20). Similar associations were found for wake time. Neither bed time nor duration were strongly associated. The top metabolites (pathways given in brackets) associated with sleep were erythrulose (advanced glycation end-product) (positive association) and several γ-glutamyl pathway metabolites, including CMPF (fatty acid, dicarboxylate), isovalerate (valine, leucine and isoleucine and fatty acid metabolism) and HWESASXX (polypeptide) (inverse association).

CONCLUSION

Within our study, several metabolites that have previously been linked to inflammation and oxidative stress (processes involved in diseases such as cardiovascular disease and cancer) were found to be associated with sleep.

Distress and sleep quality in young amphetamine-type stimulant users with an affective or psychotic illness

Misuse of amphetamine-type stimulant (ATS) drugs may disrupt key neurodevelopmental processes in young people and confer protracted neurocognitive and psychopathological harm. ATS users with a co-occurring psychiatric illness are typically excluded from research, reducing generalisability of findings. Accordingly, we conducted a cross-sectional examination of key clinical, sleep, socio-occupational and neurocognitive measures in current, past and never users of ATS drugs who were accessing a youth mental health service (headspace) for affective- or psychotic-spectrum illnesses. Contrary to hypotheses, groups did not differ in psychotic symptomology, socio-occupational functioning or neurocognitive performance. Current ATS users were however significantly more distressed and reported poorer subjective sleep quality and greater subjective sleep disturbances than never users, with a trend toward greater depressive symptomology in current users. Regression analyses revealed that depressive symptoms, daily ATS use and socio-occupational functioning predicted distress, and depressive symptoms and distress predicted subjective sleep quality. Our findings suggest that distress and poor sleep quality reflect a particular pathophysiology among ATS-using patients, which may negatively impact treatment engagement. Delineating the factors that disrupt social and neurobiological development in young people (such as substance use) warrants further investigation, including longitudinal study.

Sleep Duration Trajectories and Systemic Inflammation in Young Adults: Results From the National Longitudinal Study of Adolescent to Adult Health (Add Health)

Study Objectives

This study examines the effects of short and long sleep duration patterns in young adults on the levels of C-reactive protein (CRP), as well as the potential effect modification by sex.

Methods

Using data from waves III (age 18-26) and IV (age 24-32) of the National Longitudinal study of adolescent to adult health, we examined the association between sleep trajectories in young adults, and the risk of elevated high sensitivity-CRP (hs-CRP), a marker of systemic inflammation.

Results

Short sleep trajectories were associated with significantly elevated log-transformed hs-CRP (coefficient = 0.11, p-value .03) and with significantly higher odds of having hs-CRP levels > 3 mg/L (OR = 1.86, 95% CI 1.29, 2.67). The association was modified by sex, with the association between short sleep duration and hs-CRP limited to males. Both the continuous (coefficient 0.117, p-value = .0362) and the categorized hs-CRP (OR = 2.21, 95% CI 1.48, 3.30) were significantly elevated with short sleep durations in males, whereas no significant associations were seen in females with short sleep durations. By contrast, log hs-CRP was significantly elevated in females with long sleep durations (coefficient = 0.232, p-value = .0296), with a nonsignificant increase in the odds of having hs-CRP levels greater than 3 mg/L (OR = 1.48, 95% CI 0.75, 2.93), whereas there were no associations with long sleep duration in males.

Conclusions

Systemic inflammation, measured by an elevated level of hs-CRP, is seen with persistent short sleep duration in young adult men and persistent long sleep duration in young adult women.

Self-Reported Sleep Duration and Self-Rated Health in Young Adults

STUDY OBJECTIVES

This study aimed to determine the associations between the self-reported sleep duration and self-rated health in young adults.

METHODS

In this cross-sectional study, participants were 689 young adults (mean age 20 ± 1.35 years, 49.8% female). Sleep duration and self-rated health, as the main outcome of interest, were measured as self-reported. As potential covariates, we included sex, age, smoking status, alcohol consumption, physical activity, sedentary behavior, psychological distress, and body mass index.

RESULTS

Approximately 30% of participants slept 7-8 hours, 17.4% were short sleepers (categories < 6 hours and 6-7 hours), and 53.9% were long sleepers (categories 8-10 hours and > 10 hours of sleep). In an unadjusted model, compared with the reference category (7-8 hours of sleep), those who slept < 6 hours (odds ratio 0.20; 95% confidence interval 0.08 to 0.48) and between 6-7 hours (odds ratio 0.43; 95% confidence interval 0.26 to 0.69) were less likely to have good self-rated health. In an adjusted model, short (< 7 hours) and long sleep (> 10 hours) were both associated with poor self-rated health.

CONCLUSIONS

Our results suggest that both short (< 7 hours) and long (> 10 hours) sleepers have lower odds of having good self-rated health after adjusting for potential covariates. Health professionals should pay more attention to young adults, who have both short and long period of sleep, in order to prevent health problems and potential acute or chronic diseases.

Prolonged sleep duration as a marker of early neurodegeneration predicting incident dementia

OBJECTIVE

To evaluate the association between sleep duration and the risk of incident dementia and brain aging.

METHODS

Self-reported total hours of sleep were examined in the Framingham Heart Study (n = 2,457, mean age 72 ± 6 years, 57% women) as a 3-level variable: <6 hours (short), 6-9 hours (reference), and >9 hours (long), and was related to the risk of incident dementia over 10 years, and cross-sectionally to total cerebral brain volume (TCBV) and cognitive performance.

RESULTS

We observed 234 cases of all-cause dementia over 10 years of follow-up. In multivariable analyses, prolonged sleep duration was associated with an increased risk of incident dementia (hazard ratio [HR] 2.01; 95% confidence interval [CI] 1.24-3.26). These findings were driven by persons with baseline mild cognitive impairment (HR 2.83; 95% CI 1.06-7.55) and persons without a high school degree (HR 6.05; 95% CI 3.00-12.18). Transitioning to sleeping >9 hours over a mean period of 13 years before baseline was associated with an increased risk of all-cause dementia (HR 2.43; 95% CI 1.44-4.11) and clinical Alzheimer disease (HR 2.20; 95% CI 1.17-4.13). Relative to sleeping 6-9 hours, long sleep duration was also associated cross-sectionally with smaller TCBV (β ± SE, -1.08 ± 0.41 mean units of TCBV difference) and poorer executive function (β ± SE, -0.41 ± 0.13 SD units of Trail Making Test B minus A score difference).

CONCLUSIONS

Prolonged sleep duration may be a marker of early neurodegeneration and hence a useful clinical tool to identify those at a higher risk of progressing to clinical dementia within 10 years.

Sleep duration, obesity, and asthma, in Florida adolescents: analysis of data from the Florida Youth Risk Behavior Survey (2009-2013)

PURPOSE

To examine the association between sleep duration and asthma among Florida high school students and whether body mass index (BMI) modifies this association.

METHODS

This cross-sectional analysis included 16,728 participants in the Florida Youth Risk Behavior Survey (2009-2013). Using logistic regression, we examined the association between sleep duration and asthma, and, after controlling for potential confounders, analyzed the interaction between sleep duration and BMI.

RESULTS

Sleeping for less than 7 h or more than 8 h on school night was associated with increased odds of current asthma. Compared with 7-8 h of sleep per night, sleeping for <7 h had an OR of 1.22 (95% CI 1.07, 1.40), while sleeping for ≥9 h had and OR of 1.31 (1.06, 1.63). When stratified by body mass index (BMI), these associations were significant only in overweight adolescents, with those sleeping for <7 or ≥9 h having approximately twice the odds of having current asthma (OR = 1.75 (1.45, 2.11) and OR = 2.00 (1.32, 3.02) respectively), compared with normal weight adolescents who slept for 7-8 h per night.

CONCLUSION

The association between sleep duration and asthma in adolescents is modified by BMI. Short and long sleep durations are associated with asthma in overweight adolescents while no significant association is seen in those with normal BMI.