Sleep and circadian functioning: critical mechanisms in the mood disorders?

Discrimination in Middle Eastern and North African Americans predicts Worse Mental Health as Mediated by Sleep

Discrimination is a salient stressor linked with a variety of health outcomes including depression and anxiety among Middle Eastern and North African Americans (MENA). Among other minoritized racial and ethnic groups, sleep difficulties have been identified as potential mechanisms that explain the relationship between discrimination and mental health. However, this has not been explored within MENA samples. Thus, the focus of this study is to examine if two sleep measures (e.g., sleep disturbance and sleep-related impairment) mediate the relationship between discrimination and two mental health outcomes: depression and anxiety. We recruited 126 MENA adults from across the USA through Prolific. Findings revealed that sleep-related impairment fully mediated the relationship between discrimination and mental health outcomes, whereas sleep disturbances only partially mediated these outcomes. Results suggest sleep difficulties are one pathway that could explain the relationship between discrimination and mental health among MENA. Future work should continue to explore this relationship, as well as investigate discrimination and sleep as possible places of intervention to protect the health of MENA individuals.

Examining how gamers connect with their avatars to assess their anxiety: A novel artificial intelligence approach

Research has supported that a gamer's attachment to their avatar can offer significant insights about their mental health, including anxiety. To assess this hypothesis, longitudinal data from 565 adult and adolescent participants (Mage = 29.3 years, SD = 10.6) was analyzed at two points, six months apart. Respondents were assessed using the User-Avatar Bond (UAB) scale and the Depression Anxiety Stress Scale (DASS) to measure their connection with their avatar and their risk for anxiety. The records were processed using both untuned and tuned artificial intelligence [AI] classifiers to evaluate present and future anxiety. The findings indicated that AI models are capable of accurately and autonomously discerning cases of anxiety risk based on the gamers' self-reported UAB, age, and duration of gaming, both at present and after six months. Notably, random forest algorithms surpassed other AI models in effectiveness, with avatar compensation emerging as the most significant factor in model training for prospective anxiety. The implications for assessment, prevention, and clinical practice are discussed.

Emotional Dysregulation and Sleep Problems: A Transdiagnostic Approach in Youth

BACKGROUND

Sleep is a complex phenomenon that affects several aspects of life, including cognitive functioning, emotional regulation, and overall well-being. Sleep disturbances, especially during adolescence, can negatively impact emotional regulation, making it a critical factor in targeting psychopathology.

METHODS

This study explores the interplay between emotional dysregulation (ED) and sleep patterns in a sample of 90 adolescent patients by means of self- and parent-rated clinical measures.

RESULTS

Our findings reveal a bidirectional relationship between ED and sleep problems. Adolescents with higher affective instability experience poorer sleep quality, while those with worse sleep quality exhibit higher internalizing problems. Additionally, emotional reactivity is associated with disrupted circadian rhythms.

CONCLUSIONS

These results emphasize the significance of addressing sleep problems in the context of psychopathology treatment, potentially leading to improved outcomes. Further research is needed to determine the most effective treatment strategies, including nonpharmacological and pharmacological interventions. Understanding the intricate relationship between sleep problems and emotion regulation offers insights for more targeted and effective treatment approaches for youths struggling with ED.

Delivering a sleep intervention across a youth mental health service using non-expert practitioners: A service evaluation

AIMS

Poor sleep is highly prevalent in young people and increases risk of mental health difficulties, yet access to sleep interventions remains limited. This paper evaluates the use of a sleep intervention delivered by non-expert practitioners in a secondary care youth mental health service.

METHOD

Assistant psychologists were trained to deliver a six-session 1:1 cognitive-behavioural sleep intervention adapted for use with young people with mental health difficulties. A within-subject design assessed clinical outcomes relating to sleep (Insomnia Severity Index), psychological distress and personal goals (Goal Based Outcome Measures) at four time points.

RESULTS

High referral, intervention take-up (82.82%) and completion (70%) rates were reported, together with high baseline levels of insomnia (Insomnia Severity Index mean 20.47, SD 3.68) and poor sleep efficiency (56.36%, SD 17.23). Fifty-six young people (average age 19.2 years, SD 3.25) were included in the outcome analysis. Statistically and clinically significant improvements were seen across all outcome measures, with 68% no longer meeting clinical threshold (ISI ≥15) for insomnia at endpoint.

CONCLUSIONS

This study demonstrates exceptionally high levels of clinical need and engagement with a sleep intervention adapted specifically for young people with mental health difficulties. Whilst limited by the uncontrolled design, large improvements in insomnia and psychological distress support its effectiveness and utility in clinical settings. More robust implementation and evaluation is warranted in broader youth mental health services to promote earlier access.

Different emotion regulation strategies mediate the relations of corresponding connections within the default-mode network to sleep quality

Despite a long history of interest in the relation of emotion regulation to sleep quality, how different strategies link with sleep quality at the neural level is still poorly understood. Thus, we utilized the process model of emotion regulation as an organizing framework for examining the neurological underpinning of the links between the two emotion regulation strategies and sleep quality. 183 young adults (51.7% females, Mage = 22.16) were guided to undergo the MRI scans and then complete the Pittsburgh Sleep Quality Index (PSQI) and the emotion regulation Questionnaire (ERQ) formed by two dimensions: cognitive reappraisal and expressive suppression. Results found that emotion regulation mediated the association between functional connectivity within the intrinsic default-mode network (DMN) and sleep quality. Specifically, rsFC analysis showed that cognitive reappraisal was positively correlated with rsFC within DMN, including left superior temporal gyrus (lSTG)-left lateral occipital cortex (lLOC), lSTG-left anterior cingulate gyrus (lACG), right lateral occipital cortex (rLOC)-left middle frontal gyrus (lMFG), and rLOC-lSTG. Further mediation analysis indicated a mediated role of cognitive reappraisal in the links between the four connectivity within the DMN and sleep quality. In addition, expressive suppression was positively correlated with rsFC within DMN, including left precuneus cortex (lPrcu)-right Temporal Pole (rTP) and lPrcu- lSTG. Further mediation analysis indicated a mediated role of expressive suppression in the links between the two connectivity within the DMN and sleep quality. Overall, this finding supports the process model of emotion regulation in that the effects of reappraisal and suppression have varying neural circuits that impact that strategy's effect on sleep quality.

Network analysis of depression and anxiety symptoms and their associations with life satisfaction among Chinese hypertensive older adults: a cross-sectional study

Background

Hypertension is one of the most prevalent chronic diseases among the older adult population in China and older adults with hypertension are more susceptible to mental health problems. This study aimed to explore the network structure of depression and anxiety, and their association with life satisfaction (LS) in older adults with hypertension.

Methods

A total of 4,993 hypertensive individuals aged 60 and above were selected from the Chinese Longitudinal Healthy Longevity Survey (CLHLS 2017-2018). The design of the CLHLS study was approved by the Campus Institutional Review Board of Duke University (Pro00062871) and the Biomedical Ethics Committee of Peking University (IRB00001052-13,074). The Center for Epidemiologic Studies Depression Scale-10 (CESD-10) and the Generalized Anxiety Disorder Scale-7 (GAD-7) were used to assess depressive and anxiety symptoms. Central and bridge symptoms were identified via "Expected Influence" and "Bridge Expected Influence", respectively. Network stability was assessed using the case-dropping bootstrap technique.

Results

Network analysis identified CESD3 (Feeling blue/depressed), GAD4 (Trouble relaxing), and GAD2 (Uncontrollable worry) as the most influential central symptoms in the network of depression and anxiety. Concurrently, GAD1 (Nervousness or anxiety), CESD10 (Sleep disturbances), and CESD1 (Feeling bothered) stand as critical bridge symptoms between depression and anxiety disorders. Moreover, CESD7 (Lack of happiness) exhibited the strongest negative correlation with LS in Chinese hypertensive older adults.

Conclusion

This exploratory study represents the first investigation to examine the mutual relationship between depressive and anxiety symptoms among Chinese hypertensive older adults. Interventions addressing targeting bridge symptoms have the potential to alleviate depressive and anxiety symptoms. Furthermore, improving happiness, hope, and sleep quality in this population may mitigate the adverse effects of depression and anxiety on LS.

A Matter of Time: Racialized Time and the Production of Health Disparities

An expansive and methodologically varied literature designed to investigate racial disparities in health now exists. Empirical evidence points to an overlapping, complex web of social conditions that accelerate the pace of aging and erodes long-term health outcomes among people of color, especially Black Americans. However, a social exposure-or lack thereof-that is rarely mentioned is time use. The current paper was specifically designed to address this shortcoming. First, we draw on extant research to illustrate how and why time is a critical source of racial disparities in health. Second, we employ fundamental causes theory to explain the specific mechanisms through which the differential distribution of time across race is likely to give rise to unequal health outcomes. Finally, we introduce a novel conceptual framework that identifies and distinguishes between four distinct forms of time use likely to play an outsized role in contributing to racial disparities in health.

A pilot randomised controlled trial exploring the feasibility and efficacy of a human-AI sleep coaching model for improving sleep among university students

Objective

Sleep quality is a crucial concern, particularly among youth. The integration of health coaching with question-answering (QA) systems presents the potential to foster behavioural changes and enhance health outcomes. This study proposes a novel human-AI sleep coaching model, combining health coaching by peers and a QA system, and assesses its feasibility and efficacy in improving university students' sleep quality.

Methods

In a four-week unblinded pilot randomised controlled trial, 59 university students (mean age: 21.9; 64% males) were randomly assigned to the intervention (health coaching and QA system; n = 30) or the control conditions (QA system; n = 29). Outcomes included efficacy of the intervention on sleep quality (Pittsburgh Sleep Quality Index; PSQI), objective and self-reported sleep measures (obtained from Fitbit and sleep diaries) and feasibility of the study procedures and the intervention.

Results

Analysis revealed no significant differences in sleep quality (PSQI) between intervention and control groups (adjusted mean difference = -0.51, 95% CI: [-1.55-0.77], p = 0.40). The intervention group demonstrated significant improvements in Fitbit measures of total sleep time (adjusted mean difference = 32.5, 95% CI: [5.9-59.1], p = 0.02) and time in bed (adjusted mean difference = 32.3, 95% CI: [2.7-61.9], p = 0.03) compared to the control group, although other sleep measures were insignificant. Adherence was high, with the majority of the intervention group attending all health coaching sessions. Most participants completed baseline and post-intervention self-report measures, all diary entries, and consistently wore Fitbits during sleep.

Conclusions

The proposed model showed improvements in specific sleep measures for university students and the feasibility of the study procedures and intervention. Future research may extend the intervention period to see substantive sleep quality improvements.

Locus coeruleus activity while awake is associated with REM sleep quality in older individuals

BACKGROUNDThe locus coeruleus (LC) is the primary source of norepinephrine in the brain and regulates arousal and sleep. Animal research shows that it plays important roles in the transition between sleep and wakefulness, and between slow wave sleep and rapid eye movement sleep (REMS). It is unclear, however, whether the activity of the LC predicts sleep variability in humans.METHODSWe used 7-Tesla functional MRI, sleep electroencephalography (EEG), and a sleep questionnaire to test whether the LC activity during wakefulness was associated with sleep quality in 33 healthy younger (~22 years old; 28 women, 5 men) and 19 older (~61 years old; 14 women, 5 men) individuals.RESULTSWe found that, in older but not in younger participants, higher LC activity, as probed during an auditory attentional task, was associated with worse subjective sleep quality and with lower power over the EEG theta band during REMS. The results remained robust even when accounting for the age-related changes in the integrity of the LC.CONCLUSIONThese findings suggest that LC activity correlates with the perception of the sleep quality and an essential oscillatory mode of REMS, and we found that the LC may be an important target in the treatment of sleep- and age-related diseases.FUNDINGThis work was supported by Fonds National de la Recherche Scientifique (FRS-FNRS, T.0242.19 & J. 0222.20), Action de Recherche Concertée - Fédération Wallonie-Bruxelles (ARC SLEEPDEM 17/27-09), Fondation Recherche Alzheimer (SAO-FRA 2019/0025), ULiège, and European Regional Development Fund (Radiomed & Biomed-Hub).

Vegetarians have an indirect positive effect on sleep quality through depression condition

This study aimed to assess the association between a vegetarian diet and sleep quality among Chinese healthy adults and explore potential contributing factors. A cross-sectional study was conducted with 280 vegetarians and 280 age- and sex-matched omnivores from Shanghai, China. The Pittsburgh Sleep Quality Index (PSQI) and the Central Depression Scale (CES-D) were used to assess sleep and depression condition, respectively. A validated semi-quantitative food frequency questionnaires (SQFFQ) was employed to assess dietary intakes, and body composition was measured with InBody720. Multi-linear regression and logistic regression analysis were performed for the data analysis. The sleep quality was significantly better in the vegetarians than in the omnivores (PSQI score: 2.80 ± 2.02 vs. 3.27 ± 1.90, p = 0.005). The proportion of vegetarians who reported self-satisfied sleep was also higher than that of the omnivores (84.6% vs. 76.1%, p = 0.011). However, after adjusted for the depression condition (CES-D scores), the difference in sleep quality between vegetarians and omnivores became insignificant (p = 0.053). Compared to omnivores, vegetarians had lower depression scores (CES-D: 9.37 ± 6.24 vs. 10.94 ± 7.00, p = 0.006). After controlling for confounding factors, there was positive association between depression condition and sleep quality (β = 0.106, 95%CI: 0.083 to 0.129, p < 0.001). Similarly, participants with better CES-D score had a lower risk of sleep disorders after controlling for the same confounding factors (OR = 1.109, 95%CI: 1.072 to 1.147, p < 0.001). Different contributing factors were reported in the vegetarian group and omnivore group. In conclusion, a vegetarian diet might improve sleep quality by moderating mental health, particularly depression condition.

In vivo Locus Coeruleus activity while awake is associated with REM sleep quality in healthy older individuals

The locus coeruleus (LC) is the primary source of norepinephrine (NE) in the brain, and the LC-NE system is involved in regulating arousal and sleep. It plays key roles in the transition between sleep and wakefulness, and between slow wave sleep (SWS) and rapid eye movement sleep (REMS). However, it is not clear whether the LC activity during the day predicts sleep quality and sleep properties during the night, and how this varies as a function of age. Here, we used 7 Tesla functional Magnetic Resonance Imaging (7T fMRI), sleep electroencephalography (EEG) and a sleep questionnaire to test whether the LC activity during wakefulness was associated with sleep quality in 52 healthy younger (N=33; ~22y; 28 women) and older (N=19; ~61y; 14 women) individuals. We find that, in older, but not in younger participants, higher LC activity, as probed during an auditory mismatch negativity task, is associated with worse subjective sleep quality and with lower power over the EEG theta band during REMS (4-8Hz), which are two sleep parameters significantly correlated in our sample of older individuals. The results remain robust even when accounting for the age-related changes in the integrity of the LC. These findings suggest that the activity of the LC may contribute to the perception of the sleep quality and to an essential oscillatory mode of REMS, and that the LC may be an important target in the treatment of sleep disorders and age-related diseases.

Co-occurring insomnia and anxiety: a randomized controlled trial of internet cognitive behavioral therapy for insomnia versus internet cognitive behavioral therapy for anxiety

STUDY OBJECTIVES

Insomnia and anxiety are highly prevalent and frequently co-occur. Given limited therapeutic resources and time constraints, the aim of this study was to compare which treatment-internet cognitive behavioral therapy (CBT) for insomnia or internet CBT for anxiety-leads to the best outcomes in individuals with comorbid insomnia and anxiety.

METHODS

120 participants with comorbid insomnia and clinical anxiety (as defined by scores above the clinical cutoff on the insomnia severity index (ISI) and the generalized anxiety disorder 7-item scale (GAD-7)) were randomized to receive internet-based cognitive behavioral therapy (iCBT) for insomnia or iCBT for anxiety. The primary outcome measures were the ISI and the generalized anxiety disorder 7-item scale. Primary outcome measures were assessed before treatment, at mid-treatment, at post-treatment, and 3 months after treatment. Secondary outcome measures assessed depression symptoms, distress, and sleep diary parameters.

RESULTS

Participants in both groups experienced large reductions in symptoms of insomnia, anxiety, depression, and distress, as well as improvements in sleep efficiency and total sleep time. Improvements were maintained at follow-up. Crucially, at the end of treatment, the insomnia treatment was more effective in reducing symptoms of insomnia than the anxiety treatment, and equally effective in reducing symptoms of anxiety. Treatment gains were maintained at 3-month follow-up, however, there were no differences between groups at that time point.

CONCLUSIONS

These results suggest that in the common case of a patient presenting with comorbid insomnia and anxiety, treatment for insomnia may be the most efficient treatment strategy.

TRIAL REGISTRATION

The trial was registered with the Australian and New Zealand Clinical Trials Registry, https://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12618001141235. Trial ID: ACTRN12618001141235. Trial name: a comparison of internet-based CBT for insomnia versus internet-based CBT for anxiety in a comorbid sample.

Analyzing sleep status in children with acute leukemia

BACKGROUND

Quality sleep is essential for physical and mental health. We aimed to analyze sleep disorders in children with acute leukemia and explore associated factors.

METHODS

General data and sleep disorders in children with acute leukemia during chemotherapy were collected by general questionnaires, Children's Sleep Disorders Scale and the Parenting Stress Index-short form.

RESULTS

In total, 173 valid questionnaires were collected. The total Sleep Disorder Scale score > 39 is considered a sleep disorder, while sleep disorders accounted for 45.66% (79/173). In the cohort, 167 children had acute lymphoblastic leukemia, with 40.12% (67/167) having sleep disorders, while six children had acute non-lymphoblastic leukemia, with 50.00% (3/6) having sleep disorders. Single- and multi-factor regression analyses of age, gender, number of children in the family, and time spent using electronic devices showed that factors influencing sleep disorders in these children were mainly parental scolding and adenoid hypertrophy. Children with sleep disorders had more parental stress than those without sleep disorders (P < 0.05).

CONCLUSIONS

The high incidence of sleep disorders in children with acute leukemia is related to airway conditions and parental behaviors. Sleep disorders in children can increase parenting stress. Factors potentially affecting sleep quality should be addressed as early as possible, while parental education should be strengthened to better facilitate the physical and psychological recovery of their children.

Association Between Emotional Eating, Sociodemographic Characteristics, Physical Activity, Sleep Duration, and Mental and Physical Health in Young Adults

BACKGROUND

Emotional eating (EmE) is one of the most common eating behaviors maladaptive among young adults, however, in the Peruvian context, it remains unexplored.

OBJECTIVE

The aim of the study was to determine the association between negative EmE, sociodemographic characteristics, physical activity, sleep duration, and mental and physical health in young adults.

METHODS

A cross-sectional study was conducted in 400 young Peruvian adults living in three regions of Peru (coast, jungle, and highlands). An online survey was used to collect information on sociodemographic characteristics, physical activity, sleep duration, depressive symptoms, anxiety, hypertension, and negative EmE. In addition, self-reported anthropometric data were collected to calculate body mass index (BMI).

RESULTS

Approximately 55.8% of women presented negative EmE. Logistic regression analysis revealed that participants aged 30-39 years were less likely to have negative EmE in both female and male gender, OR; 0.24, 95% CI; 0.08-0.66, p<0.01 and OR; 0.40, 95% CI; 0.16-0.97, p<0.05, respectively. Perform physical activity 3 to 4 times 5.22 (95% CI: 1.31-20.78), 1 to 2 times a week 5.77 (95% CI: 1.91-17.44), and never 15.18 (95% CI: 3.90-59.00) were associated with negative EmE. Moreover, sleeping less than 7 hours per day (OR; 2.26, 95% CI; 1.04-4.90), depressive symptoms (OR = 6.29, 95% CI: 1.27-31.19), anxiety (OR = 14.13, 95% CI: 2.46-80. 97, p<0.01), hypertension (OR = 7.58, 95% CI: 1.24-46.17), and BMI ≥25 (overweight/obese) (OR = 1.51, 95% CI: 1.66-3.41) were associated with negative EmE.

CONCLUSION

The findings show that there is an association between negative EmE, sociodemographic characteristics, physical activity, sleep duration, and mental and physical health in young adults.

Discrimination and Health Among First-Generation Hispanic/Latinx Immigrants: the Roles of Sleep and Fatigue

INTRODUCTION

A growing literature documents the associations between discrimination and health. Emerging evidence suggests that among Hispanic/Latinx immigrants, discrimination leads to the deterioration of health outcomes over time. While sleep has been proposed as an important mediator of the relationship between discrimination and health, few studies have explicitly investigated this pathway, particularly among Hispanic/Latinx populations.

OBJECTIVE

To investigate the relationships between racial/ethnic discrimination, sleep, and physical and mental health among Hispanic/Latinx immigrants in the USA. Data and Methods Using data from a parent study of first-generation Hispanic/Latinx immigrants in the southeastern USA, we conducted sequential mediation analyses using the bootstrapping method to investigate whether self-reported sleep duration, sleep quality, and fatigue mediate the relationship(s) between self-reported discrimination, as measured by the discrimination subscale of the Riverside Acculturative Stress Inventory, and self-reported physical and mental health.

RESULTS

Nocturnal awakenings, fatigue, and sleep quality were statistically significant sequential mediators of the relationship between discrimination and physical health (b = -.001, SE = .001, CI [-.0027, -.0001]); fatigue alone also mediated this relationship (b = -.01, SE = .01, CI [-.0279, -.0003]). Nocturnal awakenings, fatigue, and sleep quality were also significant sequential mediators of the relationship between discrimination and mental health (b = -.001, SE = .001, CI [-.0031, -.0001]).

CONCLUSION

Sleep and fatigue play an important role in linking discrimination and health among first-generation Hispanic/Latinx immigrants. The development and implementation of interventions that focus on reducing fatigue among this population could mitigate the effects of unfair treatment on health outcomes.

Longing for sleep after violence: The impact of PTSD symptoms, avoidance, and pain on insomnia among female veterans

Women survivors of intimate partner violence often struggle with mental and physical problems that arise from incidents of violence. Beyond posttraumatic stress disorder (PTSD), the most common outcome, women also may suffer from debilitating chronic pain due to physical injuries sustained during particularly violent physical and/or sexual encounters. This may be a key interaction to explore as PTSD can lead to avoidance of distressing experiences, including chronic pain, resulting in enduring medical problems such as extreme sleep difficulties. This study aimed to identify if posttraumatic stress disorder (PTSD) symptoms from intimate partner violence (IPV) experiences had a conditional indirect effect on insomnia via chronic pain severity moderated by experiential avoidance among women. Female Veterans of at least 18 years of age completed online surveys at three timepoints (T1-T3) between 2014 and 2017 that included measures of PTSD, chronic pain, experiential avoidance, and insomnia. A total of 411 women participated in the initial survey at T1; 208 had a lifetime history of IPV experiences. The conditional indirect effect of PTSD symptoms (T1) on insomnia (T3) via chronic pain (T2) contingent upon experiential avoidance (T2) was also significant, demonstrating a significant moderated mediation model. This model was not significant for women without a history of IPV at T1. The findings indicate that women with IPV-related PTSD symptoms who are highly avoidant are more likely to experience chronic pain, leading to worse insomnia. Women without IPV experiences did not exhibit this same pattern. Findings have implications for improving trauma-focused treatment, approach coping strategies, pain management, and sleep interventions to address these deleterious psychological and medical issues.

Physiological markers of sleep quality: A scoping review

Understanding the associations between adequate sleep, performance and health outcomes is vital, yet a major limitation in the design and interpretation of studies of sleep and performance is the variability of subjective and objective markers used to assess sleep quality. The aim of this scoping review is to investigate how various physiological signals recorded during sleep or wakefulness relate to objective measures of cognitive or physical performance and subjectively perceived sleep quality to inform conceptual understanding of the elusive, amorphous, and multi-dimensional construct of sleep quality. We also aimed to suggest priorities for future areas of research in sleep quality and performance. We searched six databases ultimately yielding 439 studies after duplicate removal. Sixty-five studies were selected for full review. In general, correlations between objectively measured sleep and objective performance or subjectively assessed sleep quality were weak to moderate. Slow wave sleep was moderately correlated with better performance on tasks of vigilance, motor speed, and executive function as well as better subjective sleep quality and feeling well-rested, suggesting that slow wave sleep may be important for sleep quality and optimal daytime performance. However, these findings were inconsistent across studies. Increased sleep fragmentation was associated with poorer subjective sleep quality in both polysomnographic and actigraphic studies. Studies which simultaneously assessed physiologic sleep measures, performance measures and subjective sleep perception were few, limiting the ability to evaluate correlations between subjective and objective outcomes concurrently in the same individuals. Factors influencing the relationship between sleep quality and performance include circadian variability, sleep inertia, and mismatch between sleep stages studied and outcome measures of choice. Ultimately, the determination of "quality sleep" remains largely subjective and inconsistently quantifiable by current measures. Methods evaluating sleep as a continuous measure rather than traditional sleep stages may provide an intriguing approach to future studies of sleep and performance. Future well-designed studies using novel measures of sleep or multimodal ambulatory wearables assessing the three domains of sleep and performance (objective sleep physiology, objective performance, and subjective sleep quality) are needed to better define quality sleep.

Insomnia, sleep loss, and circadian sleep disturbances in mood disorders: a pathway toward neurodegeneration and neuroprogression? A theoretical review

The present paper aims at reviewing and commenting on the relationships between sleep and circadian phasing alterations and neurodegenerative/neuroprogressive processes in mood disorder. We carried out a systematic review, according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, in PubMed, PsycINFO, and Embase electronic databases for literature related to mood disorders, sleep disturbances, and neurodegenerative/neuroprogressive processes in relation to (1) neuroinflammation, (2) activation of the stress system, (3) oxidative stress, (4) accumulation of neurotoxic proteins, and (5) neuroprotection deficit. Seventy articles were collectively selected and analyzed. Experimental and clinical studies revealed that insomnia, conditions of sleep loss, and altered circadian sleep may favor neurodegeneration and neuroprogression in mood disorders. These sleep disturbances may induce a state of chronic inflammation by enhancing neuroinflammation, both directly and indirectly, via microglia and astrocytes activation. They may act as neurobiological stressors that by over-activating the stress system may negatively influence neural plasticity causing neuronal damage. In addition, sleep disturbances may favor the accumulation of neurotoxic proteins, favor oxidative stress, and a deficit in neuroprotection hence contributing to neurodegeneration and neuroprogression. Targeting sleep disturbances in the clinical practice may hold a neuroprotective value for mood disorders.

Analysis of the correlations between insomnia and mental health during the COVID-19 pandemic in Germany

Objective

This study evaluates correlations between insomnia and mental health during the COVID-19 pandemic in Germany.

Methods

The internet-based International COVID-19 Sleep Study (ICOSS) questionnaire including sociodemographic questions as well as sleep- and emotion-related scales was distributed in Germany during the COVID-19 pandemic from May 1 to September 30, 2020. Insomnia and mental state were assessed using the Insomnia Severity Index (ISI), Patient Health Questionnaire (PHQ), Generalized Anxiety Disorder (GAD-2), and visual analogue scale. Qualitative analyses of demographic characteristics were performed and correlation analyses of the variables calculated.

Results

A total of 1103 individuals participated and 858 valid questionnaires (70.61% females) were obtained. Mean age and body mass index were 41.97 ± 12.9 years and 26 ± 5.9 kg/m², respectively. Most participants were married (n = 486, 56.6%), living in the city (n = 646, 75.3%), and white (n = 442, 51.5%). The prevalence of insomnia, anxiety, and depression was 19.5% (ISI > 7), 6.6% (GAD-2 > 3), and 4.8% (PHQ-2 > 3), respectively. Compared to the insomnia group, the mean and median ISI, PHQ‑4, PHQ‑2, and GAD‑2 scores of the non-insomnia group were lower, while their mean and median quality of life and quality of health scores were significantly higher (P < 0.05). Pearson correlation analysis showed a positive correlation between the ISI and PHQ‑2 (r = 0.521, P < 0.001), GAD‑2 (r = 0.483, P < 0.001), and PHQ‑4 scores (r = 0.562, P < 0.001); however, the ISI score negatively correlated with the quality of life (r = −0.490, P < 0.001) and quality of health scores (r = −0.437, P < 0.001).

Conclusion

Insomnia, anxiety, and depression were very prevalent during the pandemic. Anxiety and depression were more severe in the insomnia than in the non-insomnia group, and insomnia and mental health are closely related.

Impact of total sleep deprivation and related mood changes on approach-avoidance decisions to threat-related facial displays

STUDY OBJECTIVES

Total sleep deprivation is known to have significant detrimental effects on cognitive and socio-emotional functioning. Nonetheless, the mechanisms by which total sleep loss disturbs decision-making in social contexts are poorly understood. Here, we investigated the impact of total sleep deprivation on approach/avoidance decisions when faced with threatening individuals, as well as the potential moderating role of sleep-related mood changes.

METHODS

Participants (n = 34) made spontaneous approach/avoidance decisions in the presence of task-irrelevant angry or fearful individuals, while rested or totally sleep deprived (27 h of continuous wakefulness). Sleep-related changes in mood and sustained attention were assessed using the Positive and Negative Affective Scale and the psychomotor vigilance task, respectively.

RESULTS

Rested participants avoided both fearful and angry individuals, with stronger avoidance for angry individuals, in line with previous results. On the contrary, totally sleep deprived participants favored neither approach nor avoidance of fearful individuals, while they still comparably avoided angry individuals. Drift-diffusion models showed that this effect was accounted for by the fact that total sleep deprivation reduced value-based evidence accumulation toward avoidance during decision making. Finally, the reduction of positive mood after total sleep deprivation positively correlated with the reduction of fearful display avoidance. Importantly, this correlation was not mediated by a sleep-related reduction in sustained attention.

CONCLUSIONS

All together, these findings support the underestimated role of positive mood-state alterations caused by total sleep loss on approach/avoidance decisions when facing ambiguous socio-emotional displays, such as fear.

No improvement of sleep from vitamin D supplementation: insights from a randomized controlled trial

Background

Vitamin D has been linked to sleep health in observational studies. Data from randomized controlled trials (RCTs) with vitamin D is scarce.

Methods

This study presents the results of a secondary analysis of 189 vitamin D insufficient participants (47.1% women) in a previously performed RCT, of which 92 were randomized to vitamin D (100,000 IU (2500 μg) as a bolus dose followed by 20,000 IU (500 μg) per week), and 97 to placebo. At baseline and after 4 months at the end of the study serum 25-hydroxyvitamin D (s-25(OH)D) was measured, and the study questionnaire assessing sleep duration, daytime sleepiness, and symptoms of insomnia, was completed.

Results

At baseline, mean s-25(OH)D was 35.0 ± 11.8 and 35.5 ± 13.3 nmol/L in the vitamin D and placebo groups, respectively. After four months, we found no statistically significant differences between the intervention groups in any of the assessed sleep outcomes, neither when stratified by sex, nor when performed in subgroups based on baseline or end of study s-25(OH)D level or presence of sleep complaints at baseline.

Conclusions

We were not able to demonstrate a significant effect of vitamin D supplementation on sleep in this vitamin D insufficient population.

•

RCT investigating vitamin D for 4 months in participants with low vitamin D status.

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Vitamin D did not improve sleep duration, excessive daytime sleepiness or insomnia.

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The role of vitamin D in sleep health remains controversial.

Prevalence and factors associated with excessive and severe daytime sleepiness among healthcare university students in the Brazilian Midwest

The present study aimed to determine the prevalence of, and factors associated with excessive and severe daytime sleepiness in healthcare university students. A cross-sectional university-based study was conducted with 1,779 students from a university located in the Brazilian Midwest State of Goiás, Brazil, in 2018. Daytime sleepiness was assessed using the Epworth Sleepiness Scale (ESS) and classified as excessive daytime sleepiness (EDS; cut-off ESS score ≥10) and severe EDS (S-EDS; cut-off ESS score ≥16). Associated factors included sociodemographic, behavioural, academic, nutritional status, and sleep-related and perceived health characteristics. Poisson regression was used for the data analysis. The mean (SD) age of the sample was 22.5 (3.84) years. The prevalence of EDS was 54.4% (95% confidence interval [CI] 51.9-56.1) and S-EDS was 10.0% (95% CI 9.2-11.7). After adjustment, a higher probability of occurrence of EDS was found among women (prevalence ratio [PR] 1.37, 95% CI 1.24-1.53), younger students (PR 1.23, 95% CI 1.07-1.42), those who were studying medicine (PR 1.14, 95% CI 1.02-1.28), with poor sleep quality (PR 1.29, 95% CI 1.17-1.43), and among those who reported constant loss of sleep due to internet use (PR 1.14, 95% CI 1.02-1.27). After adjustment, the highest probability of occurrence of S-EDS was found among women (PR 1.72, 95% CI 1.22-2.43), among those with poor sleep quality (PR 2.17, 95% CI 1.54-3.08), and medical students (PR 1.39, 95% CI 1.01-1.90). In conclusion, there was a high prevalence of daytime sleepiness among healthcare university students, especially among medical students and women.

Functional connectivity changes in insomnia disorder: A systematic review

Insomnia (ID) is the most common sleep disorder; however pathogenetic mechanisms underlying ID symptoms are not fully understood. Adopting a multifactorial view and considering ID a condition that involves interregional neuronal coordination would be useful to understand the ID pathophysiology. Functional connectivity (FC) may help to shed light on functional processes and neural correlates underlying ID symptoms. Despite a growing number of studies assessing FC anomalies, insight into ID pathophysiology is still fragmentary. This systematic review aims to search empirical evidence regarding FC changes in ID during resting-state. Thirty-one studies involving 1052 ID participants met the inclusion criteria for this review. Results suggested several associations between ID symptoms and impaired intra- and inter-hemispheric interactions of principal resting-state networks. Overall, evidence supported the hypothesis that a disrupted organization of the brain functional connectome characterizes ID, resulting in a decline in sleep, cognition, emotion, and memory. However, the wide methodological heterogeneity between reviewed studies and limitations in terms of study protocols and statistical approaches raised from this systematic review, makes it difficult to provide a univocal framework of ID pathophysiology. Future researches in this field should lead towards shared and rigorous search designs to ensure solid research evidence in the ID pathophysiology.

Heart Rate Variability, Sleep Quality, and Depression in the Context of Chronic Stress

BACKGROUND

Disrupted sleep quality is one of the proposed mechanisms through which chronic stress may lead to depression. However, there exist significant individual differences in sleep reactivity, which is the extent to which one experiences sleep disturbances in response to stress.

PURPOSE

The aim of the current study was to investigate whether low high-frequency heart rate variability (HRV), as a psychophysiological marker of poor emotional and physiological arousal regulation, predicts stress-related sleep disturbances associated with greater risk of depression symptoms.

METHODS

Using a chronic caregiving stress model, 125 mothers of adolescents with developmental disorders and 97 mothers of typically developing adolescents had their resting HRV and HRV reactivity recorded and completed a measure of depressive symptoms, as well as a 7 day sleep diary to assess their sleep quality. A moderated mediation model tested whether sleep quality mediated the association between chronic stress exposure and depressive symptoms and whether HRV moderated this mediation.

RESULTS

After controlling for participant age, body mass index, ethnicity, socioeconomic status, and employment status, poor sleep quality mediated the association between chronic stress and depressive symptoms. Resting HRV moderated this indirect effect such that individuals with lower HRV were more likely to report poorer sleep quality in the context of chronic stressor exposure, which, in turn, was related to greater depressive symptoms.

CONCLUSIONS

Lower HRV, a potential biomarker of increased sleep reactivity to stress, is associated with greater vulnerability to stress-related sleep disturbances, which, in turn, increases the risk for elevated depressive symptoms in response to chronic stress.

Sleep Disorders and Mood, Anxiety, and Post-Traumatic Stress Disorders: Overview of Clinical Treatments in the Context of Sleep Disturbances

Sleep disruptions are frequently reported by persons with mood, anxiety, and post-traumatic stress disorders, and co-occur with psychiatric disorders. There is evidence that sleep disorders can predict the likelihood of developing a future psychiatric disorder and exacerbate existing symptoms. Understanding the inter-relationships between sleep and psychiatric disorders is important. The primary goals of this article are to describe the interactions between psychiatric and sleep disorders in the context of sleep disturbances, underscore the bidirectional effects of mental health treatments on sleep disorder outcomes, and provide general recommendations to optimize treatment in the context of sleep disturbances.

Consecutive Nights of Moderate Sleep Loss Does Not Affect Mood in Healthy Young Males

Sleep loss causes mood disturbance in non-clinical populations under severe conditions, i.e., two days/nights of sleep deprivation or a week of sleep restriction with 4–5 h in bed each night. However, the effects of more-common types of sleep loss on mood disturbance are not yet known. Therefore, the aim of this study was to examine mood disturbance in healthy adults over a week with nightly time in bed controlled at 5, 6, 7, 8 or 9 h. Participants (n = 115) spent nine nights in the laboratory and were given either 5, 6, 7, 8 or 9 h in bed over seven consecutive nights. Mood was assessed daily using the Profile of Mood States (POMS-2). Mixed-linear effects models examined the effect of time in bed on total mood disturbance and subscales of anger-hostility, confusion-bewilderment, depression-dejection, fatigue-inertia, tension-anxiety, vigour-activity and friendliness. There was no effect of time in bed on total mood disturbance (F(4, 110.42) = 1.31, p = 0.271) or any of the subscales except fatigue-inertia. Fatigue-inertia was higher in the 5 h compared with the 9 h time in bed condition (p = 0.012, d = 0.75). Consecutive nights of moderate sleep loss (i.e., 5–7 h) does not affect mood but does increase fatigue in healthy males.

Age-dependent associations among insomnia, depression, and inflammation in nurses

OBJECTIVE

Insomnia and depression have been inconsistently associated with inflammation. Age may be one important moderator of these associations. This study examined associations between insomnia and depression with inflammatory biomarkers in nurses and how these associations varied by age. Design: Participants were 392 nurses ages 18-65 (Mage = 39.54 years ± 11.15, 92% female) recruited from two hospitals. Main outcome measures: Participants completed surveys to assess insomnia and depression symptoms. Serum samples were obtained and analysed for inflammatory biomarkers interleukin-6 (IL-6), C-reactive protein (CRP), interleukin-1 beta (IL-1β), and tumour necrosis factor alpha (TNF-α). Results: Neither insomnia nor depression symptoms were associated with inflammatory biomarkers. Older age was associated with higher IL-1β, and age moderated the effects of depression symptoms on CRP and TNF-α: Greater depression symptoms were associated with higher CRP (b = .14, p = .017) and TNF-α (b = .008, p = .165) among older nurses only. Conclusion: Results suggest older nurses with higher depression symptoms may be at increased risk for elevated inflammation. Interventions should consider the role of age-related processes in modifying health and well-being. Given relatively low levels of depression in the current sample, future studies should replicate results in clinical and non-nurse samples.

Younger people are more vulnerable to stress, anxiety and depression during COVID-19 pandemic: A global cross-sectional survey

The COVID-19 pandemic has had far-ranging consequences for general physical and mental health. Country-specific research reveals a general reduction in mental and physical well-being, due to measures undertaken to stop the spread of COVID-19 disease. However, research is yet to examine the impact of the pandemic on global psychological distress and its effects upon vulnerable groups. Exploration of the factors that potentially mediate the relationship between stress and mental health during this period is needed, to assist in undertaking concrete measures to mitigate psychological distress and support vulnerable groups. Therefore, this study examined the impact of the COVID-19 pandemic on psychological distress globally, and identified factors that may exacerbate decline in mental health. N = 1653 participants (mean age 42.90 ± 13.63 years; 30.3% males) from 63 countries responded to the survey. Depression and anxiety were assessed using the Patient Health Questionnaire and State Trait Anxiety Inventory, respectively. Other measures included the Perceived Stress Scale, the Pittsburgh Sleep Quality Index, 3-item UCLA Loneliness Scale and the Brief Resilient Coping Scale. Globally, consistently high levels of stress, anxiety, depression and poor sleep were observed regardless of number of COVID-19 cases. Over 70% of the respondents had greater than moderate levels of stress, with 59% meeting the criteria for clinically significant anxiety and 39% reporting moderate depressive symptoms. People with a prior mental health diagnosis experienced greater psychological distress. Poor sleep, lower levels of resilience, younger age and loneliness significantly mediated the links between stress and depression, and stress and anxiety. Age-based differences revealed that younger age-groups were more vulnerable to stress, depression and anxiety symptoms. Results show that these vulnerable individuals need more support. Age-specific interventions for modifiable factors that mediate the psychological distress need to urgently deployed to address the global mental health pandemic.

Enlightened: addressing circadian and seasonal changes in photoperiod in animal models of bipolar disorder

Bipolar disorders (BDs) exhibit high heritability and symptoms typically first occur during late adolescence or early adulthood. Affected individuals may experience alternating bouts of mania/hypomania and depression, with euthymic periods of varying lengths interspersed between these extremes of mood. Clinical research studies have consistently demonstrated that BD patients have disturbances in circadian and seasonal rhythms, even when they are free of symptoms. In addition, some BD patients display seasonal patterns in the occurrence of manic/hypomanic and depressive episodes as well as the time of year when symptoms initially occur. Finally, the age of onset of BD symptoms is strongly influenced by the distance one lives from the equator. With few exceptions, animal models useful in the study of BD have not capitalized on these clinical findings regarding seasonal patterns in BD to explore molecular mechanisms associated with the expression of mania- and depression-like behaviors in laboratory animals. In particular, animal models would be especially useful in studying how rates of change in photoperiod that occur during early spring and fall interact with risk genes to increase the occurrence of mania- and depression-like phenotypes, respectively. Another unanswered question relates to the ways in which seasonally relevant changes in photoperiod affect responses to acute and chronic stressors in animal models. Going forward, we suggest ways in which translational research with animal models of BD could be strengthened through carefully controlled manipulations of photoperiod to enhance our understanding of mechanisms underlying seasonal patterns of BD symptoms in humans. In addition, we emphasize the value of incorporating diurnal rodent species as more appropriate animal models to study the effects of seasonal changes in light on symptoms of depression and mania that are characteristic of BD in humans.

Efficacy of early warning signals and spectral periodicity for predicting transitions in bipolar patients: An actigraphy study

Early-warning signals (EWS) have been successfully employed to predict transitions in research fields such as biology, ecology, and psychiatry. The predictive properties of EWS might aid in foreseeing transitions in mood episodes (i.e. recurrent episodes of mania and depression) in bipolar disorder (BD) patients. We analyzed actigraphy data assessed during normal daily life to investigate the feasibility of using EWS to predict mood transitions in bipolar patients. Actigraphy data of 15 patients diagnosed with BD Type I collected continuously for 180 days were used. Our final sample included eight patients that experienced a mood episode, three manic episodes and five depressed episodes. Actigraphy data derived generic EWS (variance and kurtosis) and context-driven EWS (autocorrelation at lag-720) were used to determine if these were associated to upcoming bipolar episodes. Spectral analysis was used to predict changes in the periodicity of the sleep/wake cycle. The study procedures were pre-registered. Results indicated that in seven out of eight patients at least one of the EWS did show a significant change-up till four weeks before episode onset. For the generic EWS the direction of change was always in the expected direction, whereas for the context-driven EWS the observed effect was often in the direction opposite of what was expected. The actigraphy data derived EWS and spectral analysis showed promise for the prediction of upcoming transitions in mood episodes in bipolar patients. Further studies into false positive rates are suggested to improve effectiveness for EWS to identify upcoming bipolar episode onsets.

Internet-delivered cognitive behaviour therapy for adolescents with insomnia comorbid to psychiatric conditions: A non-randomised trial

Insomnia is highly prevalent among adolescents with psychiatric conditions and is known to aggravate psychiatric symptoms. Research on cognitive behaviour therapy for adolescents with comorbid insomnia (CBT-I) is still limited. The aim of this study was to investigate feasibility and preliminary effects of internet-delivered CBT for adolescents with insomnia comorbid to a psychiatric condition. Twenty-one patients (13-17 years) with comorbid insomnia were recruited from Child and Adolescent Psychiatry. All patients received 7 weeks of internet-delivered CBT-I with therapist support. Outcomes were assessed at baseline, post-treatment, and at a 4-month follow-up. The proportion of completed assessments was overall acceptable. Participants on average completed 4.48 (sd = 1.97) of the seven treatment modules and therapists on average spent 12.80 minutes (sd = 6.23) per patient and week. Results showed large statistically significant improvements on insomnia severity, sleep efficiency, sleep onset latency and sleep quality. Medium to large improvements were also seen on the psychiatric symptoms of depression, obsessive-compulsive symptoms, interpersonal sensitivity, paranoid ideation and psychoticism. These findings indicate that internet-delivered CBT is feasible and potentially promising for improving sleep and reducing psychiatric symptoms in adolescent psychiatric patients with insomnia and co-morbid psychiatric disorders. A larger randomised trial is warranted to verify these preliminary results.

The day-to-day bidirectional longitudinal association between objective and self-reported sleep and affect: An ambulatory assessment study

BACKGROUND

Ambulatory assessments offer opportunities to evaluate daily dynamics of sleep and momentary affect using mobile technologies. This study examines day-to-day bidirectional associations between sleep and affect using mobile monitoring, and evaluates whether these associations differ between people without and with current or remitted depression/anxiety.

METHODS

Two-week ecological momentary assessment (EMA) and actigraphy data of 359 participants with current (n = 93), remitted (n = 176) or no (n = 90) CIDI depression/anxiety diagnoses were obtained from the Netherlands Study of Depression and Anxiety. Objective sleep duration (SD) and efficiency were obtained from actigraphy data. Self-reported SD, sleep quality (SQ), positive affect (PA) and negative affect (NA) were assessed by electronic diaries through EMA.

RESULTS

A bidirectional longitudinal association was found between self-reported SQ and affect, while no association was found for self-reported SD and objective SD and efficiency. Better SQ predicted affect the same day (higher PA: b = 0.035, p < 0.001; lower NA: b = -0.022, p < 0.001), while lower NA on the preceding day predicted better SQ (b = -0.102, p = 0.001). The presence of current depression/anxiety disorders moderated the association between better SQ and subsequent lower NA; it was stronger for patients compared to controls (p = 0.003).

LIMITATIONS

Observational study design can only point to areas of interest for interventions.

CONCLUSIONS

This 2-week ambulatory monitoring study shows that, especially among depression/anxiety patients, better self-reported SQ predicts higher PA and lower NA the same day, while lower NA predicts better self-reported SQ. The value of mobile technologies to monitor and potentially intervene in patients to improve their affect should be explored.

Biological rhythms and chronotherapeutics in depression

Depressive syndromes are frequent and heterogeneous brain conditions with more than 90% of patients suffering from sleep complaints. Better characterizing this "sleep" domain may allow to both better treat acute episodes with existing chronotherapeutics, but also to prevent the manifestation or recurrences of mood disorders. This work aims to i) review theoretical and fundamental data of chronotherapeutics, and ii) provide practical recommendations. Light therapy (LT) can be used as a first-line monotherapy of moderate to severe depression of all subtypes. LT can be also used as a combination with antidepressant to maximize patients' response rates, which has a clear superiority to antidepressant alone. Sleep deprivation (SD) is a rapid and powerful chronotherapeutic with antidepressant responses within hours in 45-60% of patients with unipolar or bipolar depression. Different strategies should be combined to stabilize the SD antidepressant effect, including concomitant medications, repeated SD, combination with sleep phase advance and/or LT (triple chronotherapy). Melatonin treatment is of interest in remitted patients with mood disorder to prevent relapses or recurrences, if a complaint of insomnia, poor sleep quality or phase delay syndrome is associated. During the acute phase, melatonin could be used as an adjuvant treatment for symptoms of insomnia associated with depression. The cognitive behavioral therapy for insomnia (CBT-I) can be recommend to treat insomnia during euthymic phases. The Interpersonal and social rhythm therapy (IPSRT) is indicated for the acute treatment of bipolar depression and for the prevention of mood episodes. Chronotherapeutics should always be associated with behavioral measures for healthy sleep.

The relation between sigma power and internalizing problems across development

Internalizing problems are characterized by deficits in emotion processing and regulation. They are among the most common problems in children and adolescents and mark an increased risk for depressive and anxiety disorders in later life. First evidence suggests that sleep alterations are related to the development and/or persistence of mood and anxiety disorders in children, adolescents, and adults. Most recently, data from clinical samples showed that brain activity in the sigma frequency band (9-16 Hz, i.e. sleep spindle frequency) is associated with internalizing problems in children and adolescents. However, less is known about the association between sigma power and internalizing problems in healthy participants within this age group. Here, we re-analyzed longitudinal data (25 healthy subjects (18 females) at two time points (T1: childhood mean age: 9.52 ± 0.77; T2: adolescence mean age: 16.08 ± 0.91) by correlating sigma power with measures for internalizing problems. Moreover, we calculated sigma power ratios (frontal/central, frontal/parietal, frontal/occipital) to examine whether these measures would reflect developmental changes more accurately. We found that higher values of internalizing problems at T1 were related to a lower decrease in sigma power from T1 to T2 at frontal and central derivations. Furthermore, higher values of internalizing problems at T1 as well as at T2 were related to higher sigma power ratios at T2. We suggest that sigma power may reflect maturational processes (e.g. network efficiency, integrity) related to the development of internalizing problems. In particular, a stronger decrease in frontal sigma power from childhood to adolescence may indicate a healthier development. Thus, our results emphasize the role of sigma power as a useful marker for internalizing problems during adolescence.

Longitudinal correlates of sleep duration in young children

OBJECTIVE

The primary aim of this study was to longitudinally examine potential demographic and screen time correlates of nap duration, nighttime sleep duration, and total sleep duration in young children over two time points.

METHODS

Data from the supporting Healthy physical AcTive Childcare setting (HATCH) study were analyzed. Participants were 206 toddlers (19-35 months) and preschoolers (36-60 months) in Alberta and Ontario, Canada. Child age, screen time (television, video games), and sleep duration (nap, nighttime) were measured at baseline and six-month follow-up, while other demographic variables were assessed at baseline only using the HATCH parental questionnaire. Mixed models were performed to examine the associations between potential correlates and sleep duration over time.

RESULTS

In the multiple regression models, significant correlates of total sleep duration (min/d) were child age (months; B = -3.03; 95%CI:-3.88,-2.19) and parental education (bachelor's degree vs. below bachelor level; B = 29.74, 95%CI:7.43,52.06). Significant correlates of nighttime sleep duration (min/d) included child age (B = -0.81; 95CI%:-1.53,-0.10), child race/ethnicity (Caucasian vs. non-Caucasian; B = 15.31; 95%CI:0.38,30.25), household income (>$150,000 vs. <$50,000; B = 32.93, 95%CI:9.80,56.06), television time (B = -0.19, 95%CI:-0.32,-0.05), video games time (B = -0.19, 95%CI: -0.38, -0.01) and total screen time (B = -0.19; 95%CI:-0.29,-0.08). Significant correlates of nap duration (min/d) were child age (B = -2.10; 95%CI:-2.68,-1.51) and race/ethnicity (Caucasian vs. non-Caucasian; B = -13.73; 95%CI:-25.78,-1.68).

CONCLUSION

Young children who were non-Caucasian, from lower income families, who had less-educated parents, or who had more screen time tended to have shorter sleep duration. Targeting these demographic groups and screen time appears important for promoting adequate sleep duration in early childhood.

Poverty, depression, and anxiety: Causal evidence and mechanisms

Why are people who live in poverty disproportionately affected by mental illness? We review the interdisciplinary evidence of the bidirectional causal relationship between poverty and common mental illnesses-depression and anxiety-and the underlying mechanisms. Research shows that mental illness reduces employment and therefore income, and that psychological interventions generate economic gains. Similarly, negative economic shocks cause mental illness, and antipoverty programs such as cash transfers improve mental health. A crucial step toward the design of effective policies is to better understand the mechanisms underlying these causal effects.

The Big Three Health Behaviors and Mental Health and Well-Being Among Young Adults: A Cross-Sectional Investigation of Sleep, Exercise, and Diet

BACKGROUND

Sleep, physical activity, and diet have been associated with mental health and well-being individually in young adults. However, which of these "big three" health behaviors most strongly predicts mental health and well-being, and their higher-order relationships in predictive models, is less known. This study investigated the differential and higher-order associations between sleep, physical activity, and dietary factors as predictors of mental health and well-being in young adults.

METHOD

In a cross-sectional survey design, 1,111 young adults (28.4% men) ages 18-25 from New Zealand and the United States answered an online survey measuring typical sleep quantity and quality; physical activity; and consumption of raw and processed fruit and vegetables, fast food, sweets, and soda, along with extensive covariates (including demographics, socioeconomic status, body mass index, alcohol use, smoking, and health conditions) and the outcome measures of depressive symptoms [measured by the Center for Epidemiological Depression Scale (CES-D)] and well-being (measured by the Flourishing Scale).

RESULTS

Controlling for covariates, sleep quality was the strongest predictor of depressive symptoms and well-being, followed by sleep quantity and physical activity. Only one dietary factor-raw fruit and vegetable consumption-predicted greater well-being but not depressive symptoms when controlling for covariates. There were some higher-order interactions among health behaviors in predicting the outcomes, but these did not survive cross-validation.

CONCLUSION

Sleep quality is an important predictor of mental health and well-being in young adults, whereas physical activity and diet are secondary but still significant factors. Although strictly correlational, these patterns suggest that future interventions could prioritize sleep quality to maximize mental health and well-being in young adults.

Effects and feasibility of hyperthermic baths in comparison to exercise as add-on treatment to usual care in depression: a randomised, controlled pilot study

BACKGROUND

Limitations of current therapy of depression highlight the need for an immediately available, easily implementable add-on treatment option with high acceptance from patients. Hyperthermic baths (HTB) are a form of balneotherapy with head-out-of-water-immersion in a hot pool or tub at 40 °C for 15-20 min. A prior study suggests that HTB added to usual depression care can have antidepressant effects.

METHOD

Single-site, open-label randomised controlled 8-week parallel-group pilot study at a university outpatient clinic. 45 medically stable outpatients with moderate depression as determined by the 17-item Hamilton Depression Rating Scale (HAM-D) score ≥ 18 and a score ≥ 2 on item 1 (Depressed Mood) were recruited. They were randomised to twice weekly HTB (n = 22) or a physical exercise program (PEP) of moderate intensity (n = 23). Primary outcome measure was the change in HAM-D total score from baseline (T0) to the 2-week time point (T1). Linear regression analyses, adjusted for baseline values, were performed to estimate intervention effects on an intention-to-treat (ITT) and per-protocol (PP) principle.

RESULTS

Forty-five patients (HTB n = 22; PEP n = 23) were analyzed according to ITT (mean age = 48.4 years, SD = 11.3, mean HAM-D score = 21.7, SD = 3.2). Baseline-adjusted mean difference after 2 weeks was 4.3 points in the HAM-D score in favor of HTB (p < 0.001). Compliance with the intervention and follow-up was far better in the HTB group (2 vs 13 dropouts). Per protocol analysis only showed superiority of HTB as a trend (p = 0.068). There were no treatment-related serious adverse events. Main limitation: the number of dropouts in the PEP group (13 of 23) was higher than in other trials investigating exercise in depression. Due to the high number of dropouts the effect in the ITT-analysis may be overestimated.

CONCLUSIONS

HTB added to usual care may be a fast-acting, safe and easy accessible method leading to clinically relevant improvement in depression severity after 2 weeks; it is also suitable for persons who have problems performing exercise training.

TRIAL REGISTRATION

German Clinical Trials Register (DRKS) with the registration number DRKS00011013 (registration date 2016-09-19) before onset of the study.

Low-intensity sleep intervention in a youth mental health service: a case series analysis

BACKGROUND

There is increasing evidence of a strong association between sleep and mental health in both adolescents and adults. CBT for insomnia is being applied to good effect with adults with mental health difficulties but there are few studies examining its applicability to adolescents within mental health services.

METHOD

We carried out a case series analysis (n = 15) looking at the feasibility, accessibility and impact of a low-intensity sleep intervention for young people (14-25 years) being seen by a secondary care Youth Mental Health team in the UK. The intervention was based on cognitive behavioural therapy for insomnia (CBTi) and acceptance and commitment therapy (ACT) approaches and involved six individual sessions delivered on a weekly basis by a graduate psychologist. Routine outcome measures were used to monitor insomnia, psychological distress and functioning with assessments at baseline, session 3, session 6 and at 4 weeks after end of intervention. All participants scored in the clinical range for insomnia at the start of the study.

RESULTS

High uptake, attendance and measure completion rates were observed. Large effect sizes were observed for insomnia, psychological distress and functioning. Twelve of the fifteen participants (80%) no longer scored above threshold for insomnia at follow-up. All seven under-18s no longer met threshold for clinical 'caseness' on the Revised Child Anxiety and Depression Scale (RCADS) at follow-up.

DISCUSSION

The findings suggest that the intervention was well accepted by young people and feasible to apply within a secondary care setting. Strong effect sizes are encouraging but are probably inflated by the small sample size, uncontrolled design and unblinded assessments.

An Integrated Sleep and Reward Processing Model of Major Depressive Disorder

Major depressive disorder with comorbid sleep disturbance has been associated with negative outcomes, including lower rates of treatment response and a greater likelihood of depressive relapse compared to those without sleep disturbance. However, little, if any, research has been conducted to understand why such negative treatment outcomes occur when sleep disturbance is present. In this conceptual review, we argue that the relationship of sleep disturbance and negative treatment outcomes may be mediated by alterations in neural reward processing in individuals with blunted trait-level reward responsivity. We first briefly characterize sleep disturbance in depression, discuss the nature of reward processing impairments in depression, and summarize the sleep/reward relationship in healthy human subjects. We then introduce a novel Integrated Sleep and Reward model of the course and maintenance of major depressive disorder and present preliminary evidence of sleep and reward interaction in unipolar depression. Finally, we discuss limitations of the model and offer testable hypotheses and directions for future research.

Association between affective temperaments and mood features in bipolar disorder II: The role of insomnia and chronobiological rhythms desynchronization

BACKGROUND

Bipolar disorders are complex disorders involving the interaction of multiple factors. Affective temperaments, insomnia, and chronobiological rhythms desynchronization may all contribute to bipolar disorder. Since there is a paucity of research examining this topic we aimed to study how they are interrelated and collectively associated with clinical features of bipolar disorder.

METHOD

One-hundred patients with Bipolar Disorder type II depressive episode with and without mixed features were recruited and compared. Subjects were evaluated with SCID -5, the Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN), the Insomnia Severity Index (ISI), and the Temperament Evaluation of Memphis, Pisa, Paris, and San Diego Auto-questionnaire (TEMPS-A) while evaluating depressive (Beck Depression Inventory-BDI-II) and manic (Young Mania Rating Scale-YMRS) symptoms. Logistic regression and mediation analyses were conducted.

RESULTS

Subjects with mixed features showed a higher scores in both insomnia and chronobiological rhythms scores. When considering affective temperaments not only depressive, cyclothymic and irritable temperaments predicted mood symptoms but also insomnia (depressive symptoms O.R. 4.17, p = 0.043) and chronobiological sleep de-synchronization (manic symptoms O.R. 8.69, p = 0.001). Insomnia symptoms and chronobiological alterations mediated the association between affective temperaments and mood symptoms.

LIMITATIONS

the cross-sectional design limited any causal interpretation.

CONCLUSION

Subjects with mixed features showed a greater severity of insomnia and chronobiological rhythm de-synchronization compared to subjects without. Insomnia and chronobiological alterations may contribute to mood disorders together with affective temperaments in a complex interplay also mediating their effect on mood. Preventive strategies for bipolars should also act on the dysregulation of sleep and circadian rhythms.

Disruptions in the Amount and Timing of Sleep and Repetitive Negative Thinking in Adolescents

Objective/Background: Numerous psychiatric conditions characterized by repetitive negative thinking (RNT) are also frequently associated with disruptions in the duration and timing of sleep. The emerging literature supports that these types of sleep disruptions may be associated with negative psychological consequences such as depressed mood, anxiety, and poor emotion regulation, all of which have features of RNT. There is a paucity of research on the association between RNT and disruptions in sleep duration and timing in adolescents. The aim of the current study was to examine if sleep duration and timing in an adolescent sample would be predictive of RNT. Participants: Participants included 1,021 adolescents (ages 11 to 17) from a public school district in upstate New York. Methods: Participants completed a survey about their sleep practices, symptoms of psychopathology, and RNT. Results: Results indicated that sleep timing was predictive of RNT, but sleep duration was not. This result remained even after controlling for symptoms of psychopathology. Further, sleep onset latency was also predictive of RNT. Conclusions: These results indicate that it may be important to make the distinction between sleep duration and sleep timing. Sleep timing may uniquely impact RNT in adolescents.

Effects of REM sleep during a daytime nap on emotional perception in individuals with and without depression

BACKGROUND

It has been theoretically proposed that alteration in sleep physiology may contribute to the development of biased emotional processing featured in depression. The current study investigated the role of sleep and especially REM in modulating perception of emotional faces in depressed versus non-depressed individuals using a napping paradigm.

METHODS

Forty-six individuals with major depressive disorder and 66 age- and education-matched healthy controls completed an emotional face perception task before and after random assignment to one of the three intention-to-treat (ITT) conditions, namely 30-min-nap, 90-min-nap and wake. To delineate the effects of REM, as-treated (30-min-nap, 90-min-REM-nap, 90-min-noREM-nap and wake) analyses were also conducted.

RESULTS

Repeated measures multivariate analysis of covariance (MANCOVA) showed a significant Time *Group *Condition interaction on angry faces for both analyses of ITT (p = .017) and AT (p = .027). Pairwise comparison with Bonferroni corrections revealed a significant increase in the intensity rating of angry faces only after 90-min-REM-nap in the depressed group. Correlational analyses convergingly showed that the increase of intensity rating of angry faces was associated with the proportion of REM sleep in the depressed group, p = .035.

LIMITATIONS

The observed effect of REM sleep during daytime napping may not represent the effect of nighttime REM sleep in depression.

CONCLUSIONS

We provide the first evidence of the association of daytime sleep, particularly REM sleep, with a more negative perception of angry faces exclusively in individuals with depression. The differentiated impact of sleep observed may contribute to the development of altered emotional processing in depression.

Integrating sleep, neuroimaging, and computational approaches for precision psychiatry

In advancing precision psychiatry, we focus on what imaging technology and computational approaches offer for the future of diagnostic subtyping and personalized tailoring of interventions for sleep impairment in mood and anxiety disorders. Current diagnostic criteria for mood and anxiety tend to lump different forms of sleep disturbance together. Parsing the biological features of sleep impairment and brain circuit dysfunction is one approach to identifying subtypes within these disorders that are mechanistically coherent and offer targets for intervention. We focus on two large-scale neural circuits implicated in sleep impairment and in mood and anxiety disorders: the default mode network and negative affective network. Through a synthesis of existing knowledge about these networks, we pose a testable framework for understanding how hyper- versus hypo-engagement of these networks may underlie distinct features of mood and sleep impairment. Within this framework we consider whether poor sleep quality may have an explanatory role in previously observed associations between network dysfunction and mood symptoms. We expand this framework to future directions including the potential for connecting circuit-defined subtypes to more distal features derived from digital phenotyping and wearable technologies, and how new discovery may be advanced through machine learning approaches.

Perception of Sleep Disturbances due to Bedtime Use of Blue Light-Emitting Devices and Its Impact on Habits and Sleep Quality among Young Medical Students

Introduction

The use of blue light-emitting devices (smartphones, tablets, and laptops) at bedtime has negative effects on sleep due to light stimulation and/or problematic excessive use. We aimed to evaluate, among young medical students, if the perception of sleep disturbances due to bedtime use of these devices is consistent with healthier habits and a better sleep quality.

Materials and methods

294 medical students in medicine and pharmacy from the Faculty of Medicine and Pharmacy of Rabat, Morocco, took part in this anonymous and voluntary cross-sectional study and answered an electronic questionnaire. Student and Mann–Whitney U tests were used to compare variables between 2 groups based on their perception of sleep disturbances. The level of significance was p ≤ 0.05.

Results

286 students (97.3%) used a blue light-emitting smart device at bedtime before sleep, and sleep quality was poor (Pittsburgh Sleep Quality Index, PSQI > 5) in 101 students (35.3%). The perception of sleep disturbances due to this night usage was reported by 188 of them (65.7%). In this group, 154 (81.9%) used their device with all the lights turned off in the room (p=0.02), 34 (18.1%) put devices under pillows (p=0.04), 114 (60.6%) interrupted sleep to check messages (p < 0.001), and the mean duration use of these technologies at bedtime was 2 h ± 23 min per night (p=0.02). Also, the mean sleep duration was 6.3 hours ± 1.25 (p=0.04), 119 (63.3%) presented fatigue on waking more than one time per week (p=0.04), and 76 (40.4%) presented poor sleep quality (75.2% of the students with PSQI > 5) (p=0.005).

Conclusions

Despite the perception of sleep disturbances due to bedtime use of blue light-emitting devices, unhealthy sleep habits tend to be frequent in young medical students and worrying because it is associated to significant poor sleep quality.

Sleep in seasonal affective disorder

Sleep in seasonal affective disorder (SAD) has been primarily characterized by delayed sleep timing and self-reports of hypersomnolence. It is unclear whether delayed sleep timing is due to circadian or behavioral misalignment and if effective treatments operate independently of the circadian system. Discrepancies between self-report and actigraphic/polysomnographic sleep duration in SAD hinder clarification of hypersomnolence as a cardinal symptom. Previous studies have largely neglected the summer remission period in SAD, which could yield valuable insight to the role sleep disturbances play in the onset and recurrence of winter depressive episodes. Future studies should incorporate multi-method, multi-season assessment of sleep and circadian rhythms to best characterize relevant sleep-circadian phenotypes. Empirically determining sleep phenotypes present in SAD will pave the way for targeted sleep interventions.