Update of sleep alterations in depression

Associations between masturbation frequency, anxiety, and sleep disturbances during the COVID-19 era

The COVID-19 pandemic has markedly influenced people's lifestyle and sexual behaviors, including masturbation patterns. This study delved into how masturbation frequency could impact anxiety levels, sleep quality, and somatic symptoms post-masturbation among Chinese adults during this period. From December 2022 to January 2023, we conducted a cross-sectional survey, gathering data via WenJuanXing, a leading online survey platform in China. This platform facilitated the recruitment of a diverse cohort, spanning various age groups and geographical locations. Masturbation frequency among participants was subjectively categorized into three levels: 'lesser' (a few times over the past year), 'moderate' (once to three times a month), and 'greater' (weekly to almost daily). To assess anxiety levels and sleep quality, we employed the Generalized Anxiety Disorder 7-item (GAD-7) scale and the Pittsburgh Sleep Quality Index (PSQI), respectively. Among 1500 participants, we received 1423 valid responses. Among these, 65% (n = 930) reported engaging in masturbation in the past year, of whom 87.5% reported subjectively experiencing various levels of fatigue post-masturbation. These 930 responses were subsequently analyzed in-depth (e.g., non-parametric test and pathway analysis), with ages ranging from 18 to 54 years (mean age = 30.5, SD = 7.42). Notably, our findings indicate that participants with greater masturbation frequency exhibited higher anxiety levels [GAD-7 median score: 6 (lesser) vs. 4 (moderate) vs. 8 (greater), p < 0.001, Cohen's f = 0.41] and poorer sleep quality [PSQI median score: 5 (lesser) vs. 4 (moderate) vs. 7 (greater), p < 0.001, Cohen's f = 0.46]. A rough positive correlation between masturbation frequency and PSQI score was also observed (β = 0.16, p < 0.001). These results suggest potential mental and sleep benefits at moderate frequencies, especially in contrast to greater frequencies. However, the cross-sectional design and subjective categorization of masturbation frequency in our study limit our ability to draw definitive causal conclusions. These limitations highlight the need for future longitudinal research employing more precise categorizations of masturbation behavior, such as frequency, to delve deeper into these relationships and understand their underlying mechanisms.

Relationship between subjective and objective fatigue and sleep characteristics in individuals with anxiety and mood disorders: An exploratory study

OBJECTIVE

Fatigue and sleep disturbances are important symptoms of anxiety and mood disorders (AMD). Studies about the relationship between these variables usually rely on self-report assessments. Therefore, the aim of our exploratory study was to investigate the independent correlations between subjective and objective fatigue and sleep characteristics in individuals with AMD.

METHODS

In sum, 233 individuals with AMD attending a stress-related disorders day care unit (78.5 % females, mean age 39.0 years old) participated in a cross-sectional study. Participants completed the Patient Health Questionnaire-9, Generalized Anxiety Disorder-7, Multidimensional Fatigue Inventory-20, and Pittsburgh Sleep Quality Index self-report questionnaires, as well as an exercise capacity workload test for assessing objective fatigue and polysomnography monitoring for evaluation of sleep structure.

RESULTS

In individuals with AMD, exercise capacity workload was associated with lower percent of stage 1 sleep (β = - 0.17, p = 0.006), REM latency (β = -0.13, p = 0.042), and wake after sleep onset (β = -0.12, p = 0.039). General fatigue was associated with a higher percent of body movements (β = 0.12, p = 0.047), as well as mental fatigue was associated with a higher percent of body movements (β = 0.13, p = 0.029), and a higher score on the PSQI (β = 0.21, p = 0.002).

CONCLUSIONS

Objective sleep characteristics were associated with objective assessment of fatigue, while subjective sleep quality was associated with subjectively assessed mental fatigue.

An exploration of actigraphy in the context of ketamine and treatment-resistant depression

OBJECTIVES

This study explored the potential of non-parametric and complexity analysis metrics to detect changes in activity post-ketamine and their association with depressive symptomatology.

METHODS

Individuals with treatment-resistant depression (TRD: n = 27, 16F, 35.9 ± 10.8 years) and healthy volunteers (HVs: n = 9, 4F, 36.4 ± 9.59 years) had their activity monitored during an inpatient, double-blind, crossover study where they received an infusion of ketamine or saline placebo. All participants were 18-65 years old, medication-free, and had a MADRS score ≥20. Non-parametric metrics averaged over each study day, metrics derived from complexity analysis, and traditionally calculated non-parametric metrics averaged over two weeks were calculated from the actigraphy time series. A separate analysis was conducted for a subsample (n = 17) to assess the utility of these metrics in a hospital setting.

RESULTS

In HVs, lower intradaily variability was observed within daily rest/activity patterns post-ketamine versus post-placebo (F = 5.16(1,15), p = 0.04). No other significant effects of drug or drug-by-time or correlations between depressive symptomatology and activity were detected.

CONCLUSIONS

Weak associations between non-parametric variables and ketamine were found but were not consistent across actigraphy measures.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT00088699.

Regulation of dendritic spines in the amygdala following sleep deprivation

The amygdala is a hub of emotional circuits involved in the regulation of cognitive and emotional behaviors and its critically involved in emotional reactivity, stress regulation, and fear memory. Growing evidence suggests that the amygdala plays a key role in the consolidation of emotional memories during sleep. Neuroimaging studies demonstrated that the amygdala is selectively and highly activated during rapid eye movement sleep (REM) and sleep deprivation induces emotional instability and dysregulation of the emotional learning process. Regulation of dendritic spines during sleep represents a morphological correlate of memory consolidation. Several studies indicate that dendritic spines are remodeled during sleep, with evidence for broad synaptic downscaling and selective synaptic upscaling in several cortical areas and the hippocampus. Currently, there is a lack of information regarding the regulation of dendritic spines in the amygdala during sleep. In the present work, we investigated the effect of 5 h of sleep deprivation on dendritic spines in the mouse amygdala. Our data demonstrate that sleep deprivation results in differential dendritic spine changes depending on both the amygdala subregions and the morphological subtypes of dendritic spines. We observed decreased density of mushroom spines in the basolateral amygdala of sleep deprived mice, together with increased neck length and decreased surface area and volume. In contrast, we observed greater densities of stubby spines in sleep deprived mice in the central amygdala, indicating that downscaling selectively occurs in this spine type. Greater neck diameters for thin spines in the lateral and basolateral nuclei of sleep deprived mice, and decreases in surface area and volume for mushroom spines in the basolateral amygdala compared to increases in the cental amygdala provide further support for spine type-selective synaptic downscaling in these areas during sleep. Our findings suggest that sleep promotes synaptic upscaling of mushroom spines in the basolateral amygdala, and downscaling of selective spine types in the lateral and central amygdala. In addition, we observed decreased density of phosphorylated cofilin immunoreactive and growth hormone immunoreactive cells in the amygdala of sleep deprived mice, providing further support for upscaling of dendritic spines during sleep. Overall, our findings point to region-and spine type-specific changes in dendritic spines during sleep in the amygdala, which may contribute to consolidation of emotional memories during sleep.

Association of lower extremity lymphedema with pelvic floor functions, sleep quality, kinesiophobia, body image in patients with gynecological cancers

The aim was to investigate the relationship between lower extremity lymphedema and pelvic floor functions, sleep quality, kinesiophobia, body image in patients with gynecological cancer the effect of lymphedema severity on pelvic floor dysfunction (PFD), sleep quality, fear of movement, and body image in patients with lower extremity lymphedema after gynecologic cancer. A total of 103 patients (52 patients with lymphedema and 51 patients without lymphedema) after gynecologic cancer surgery were included in March-June 2022. Bilateral circumferential measurements were taken with a tape measure at different levels to create groups. These measurements determined limb volumes by summing segment volumes derived from the truncated cone formula. For data collection, all patients were presented with the Gynecologic Cancer Lymphedema Questionnaire (GCLQ), the Global Pelvic Floor Bother Questionnaire (GPFBQ), the Pittsburgh Sleep Quality Index (PSQI), the Tampa Scale of Kinesiophobia (TSK) and the Body Image Scale (BIS) one time. The severity of lymphedema symptoms was quite high in patients with lymphedema (GCLQ Total: 13.6) (p < .05). Patients with lymphedema had higher GCLQ total scores, GPFBQ1 (stress urinary incontinence), GPFBQ4 (urge urinary incontinence), GPFBQ8 (fecal incontinence), kinesiophobia and, body image scores than patients without lymphedema (p < .05). The sleep quality levels of patients with lymphedema and patients without lymphedema were similar (p > .05). A significant negative correlation was found between GLCQ total score and body image (p < .05). There was a positive correlation between kinesiophobia and pelvic floor symptoms and a negative correlation between kinesiophobia and body image (p < .05). In this study, it was observed that in patients who developed lymphedema after gynecologic cancer surgery, pelvic floor symptoms and kinesiophobia increased and the severity of lymphedema negatively affected body image. Reducing lymphedema in these patients may improve pelvic floor health, mobility, and body image.

Restraint stress induced anxiety and sleep in mice

In humans and animals, exposure to changes in internal or external environments causes acute stress, which changes sleep and enhances neurochemical, neuroendocrine, and sympathetic activities. Repeated stress responses play an essential role in the pathogenesis of psychiatric diseases and sleep disorders. However, the underlying mechanism of sleep changes and anxiety disorders in response to acute stress is not well established. In the current study, the effects of restraint stress (RS) on anxiety and sleep-wake cycles in mice were investigated. We found that after RS, the mice showed anxiety-like behavior after RS manipulation and increased the amounts of both non-rapid eye movement (NREM) and rapid eye movement (REM) sleep in the dark period. The increase in sleep time was mainly due to the increased number of episodes of NREM and REM sleep during the dark period. In addition, the mice showed an elevation of the EEG power spectrum of both NREM and REM sleep 2 h after RS manipulation. There was a significant reduction in the EEG power spectrum of both NREM and REM sleep during the darkperiod in the RS condition. The expression of the c-Fos protein was significantly increased in the parabrachial nucleus, bed nucleus of the stria terminalis, central amygdala, and paraventricular hypothalamus by RS manipulation. Altogether, the findings from the present study indicated that neural circuits from the parabrachial nucleus might regulate anxiety and sleep responses to acute stress, and suggest a potential therapeutic target for RS induced anxiety and sleep alterations.

Synergistic antidepressant effects of citalopram and SB-334867 in the REM sleep-deprived mice: Possible role of BDNF

This study was done to evaluate the effect of co-treatment of orexin agents along with citalopram on the modulation of depression-like behavior and the expression of BDNF in the prefrontal cortex (PFC) of sleep-deprived male mice. A sleep deprivation model was performed in which rapid eye movement (REM) sleep was completely prohibited, and non-REM sleep was intensely reduced for 24 h. For drug microinjection, the guide cannula was surgically fixed in the left lateral ventricle of mice. Furthermore, we used the open-field test (OFT), forced swim test (FST), tail suspension test (TST), and splash test for recording depression-like behavior as well as Real-Time PCR amplification for assessing the expression of BDNF in the PFC of REM sleep-deprived mice. Our results revealed that REM sleep deprivation did not change locomotor activity while increased depressive-like behavior in FST, TST, and splash tests. However, the expression of BDNF was decreased in the PFC. Intraperitoneally (i.p.) administration of citalopram induced antidepressant effect in the normal and REM sleep-deprived mice. Moreover, intracerebroventricular (i.c.v.) microinjection of a non-effective dose of SB-334867, an orexin antagonist, potentiated the antidepressant-like effect of citalopram. On the other hand, a non-significant dosage of orexin-1 reversed the antidepressant effect of citalopram in the normal and REM sleep-deprived animals. Furthermore, our results showed that injection of citalopram alone or with SB-334867 increased the mRNA expression level of BDNF in the PFC of REM sleep-deprived mice. These data suggest that REM sleep deprivation interferes with the neural systems underlying the depression-like process and supports a likely interaction of the orexin system with citalopram on the modulation of depression-like behavior in REM sleep-deprived mice.

Sleep and Mental Health Issues in Current and Former Athletes: A Mini Review

Sleep and mental health are important aspects of human health that work concurrently. However, sleep and mental health disorders are often overlooked and undiagnosed in sport due to the negative stigma associated with them. Evidence suggests that athletes are disproportionately affected by mental health issues and sleep problems. Internal and external pressures contribute to psychological distress. Variable competition times, travel and stress are detrimental to sleep quality. Retirement from sport can deteriorate sleep and psychological wellbeing, particularly for those who retired involuntarily and identify strongly with their athletic role. When untreated, these issues can manifest into a range of clinical disorders. This is concerning, not only for compromised athletic performance, but for general health and wellbeing beyond sport. Previous research has focussed on sleep and health independently among currently competing, or former, athletes. To date, no research has comprehensively assessed and compared sleep complaints and mental health issues between these two cohorts. Moreover, research has failed to obtain data across a variety of different competition levels, sports, and genders, leaving the current scope of the literature narrow. Comorbid conditions (e.g., concussion history, obesity), ex-college athletes, and mental health has been the focus of existing literature post-retirement. Future research would benefit from employing both quantitative and qualitative methodologies to comprehensively assess the prevalence and severity of sleep and mental health disorders across current and retired athletes. Research outcomes would inform education strategies, safeguarding athletes from these issues by reducing negative stigmas associated with help-seeking in sport and ultimately increase self-guided treatment.

Advances in optogenetic studies of depressive-like behaviors and underlying neural circuit mechanisms

BACKGROUNDS

The neural circuit mechanisms underlying depression remain unclear. Recently optogenetics has gradually gained recognition as a novel technique to regulate the activity of neurons with light stimulation. Scientists are now transferring their focus to the function of brain regions and neural circuits in the pathogenic progress of depression. Deciphering the circuitry mechanism of depressive-like behaviors may help us better understand the symptomatology of depression. However, few studies have summarized current progress on optogenetic researches into the neural circuit mechanisms of depressive-like behaviors.

AIMS

This review aimed to introduce fundamental characteristics and methodologies of optogenetics, as well as how this technique achieves specific neuronal control with spatial and temporal accuracy. We mainly summarized recent progress in neural circuit discoveries in depressive-like behaviors using optogenetics and exhibited the potential of optogenetics as a tool to investigate the mechanism and possible optimization underlying antidepressant treatment such as ketamine and deep brain stimulation.

METHODS

A systematic review of the literature published in English mainly from 2010 to the present in databases was performed. The selected literature is then categorized and summarized according to their neural circuits and depressive-like behaviors.

CONCLUSIONS

Many important discoveries have been made utilizing optogenetics. These findings support optogenetics as a powerful and potential tool for studying depression. And our comprehension to the etiology of depression and other psychiatric disorders will also be more thorough with this rapidly developing technique in the near future.

Nucleus Accumbens Medium Spiny Neuron Subtypes Differentially Regulate Stress-Associated Alterations in Sleep Architecture

BACKGROUND

Stress is implicated in the pathophysiology of major depression and posttraumatic stress disorder. These conditions share core features, including motivational deficits, heighted anxiety, and sleep dysregulation. Chronic stress produces these same features in rodents, with some individuals being susceptible or resilient, as seen in humans. While stress-induced neuroadaptations within the nucleus accumbens are implicated in susceptibility-related dysregulation of motivational and emotional behaviors, their effects on sleep are unclear.

METHODS

We used chemogenetics (DREADDs [designer receptors exclusively activated by designer drugs]) to examine the effects of selective alterations in activity of nucleus accumbens medium spiny neurons expressing dopamine D₁ receptors (D1-MSNs) or dopamine D₂ receptors (D2-MSNs) on sleep-related end points. Mice were implanted with wireless transmitters enabling continuous collection of data to quantify vigilance states over a 20-day test period. Parallel cohorts were examined in behavioral tests assessing stress susceptibility.

RESULTS

D1- and D2-MSNs play dissociable roles in sleep regulation. Stimulation of inhibitory or excitatory DREADDs expressed in D1-MSNs exclusively affects rapid eye movement sleep, whereas targeting D2-MSNs affects slow wave sleep. The combined effects of D1-MSN inhibition and D2-MSN activation on sleep resemble those of chronic social defeat stress. Alterations in D1-MSN function also affect stress susceptibility in social behavior tests. Elevation of CREB (cAMP response element-binding protein) within D1-MSNs is sufficient to produce stress-like effects on rapid eye movement sleep.

CONCLUSIONS

In addition to regulation of motivational and emotional behaviors, the nucleus accumbens also influences sleep, an end point with high translational relevance. These findings provide a neural basis for comorbidity in key features of stress-related illness.

Sleep and Memory Consolidation Dysfunction in Psychiatric Disorders: Evidence for the Involvement of Extracellular Matrix Molecules

Sleep disturbances and memory dysfunction are key characteristics across psychiatric disorders. Recent advances have revealed insight into the role of sleep in memory consolidation, pointing to key overlap between memory consolidation processes and structural and molecular abnormalities in psychiatric disorders. Ongoing research regarding the molecular mechanisms involved in memory consolidation has the potential to identify therapeutic targets for memory dysfunction in psychiatric disorders and aging. Recent evidence from our group and others points to extracellular matrix molecules, including chondroitin sulfate proteoglycans and their endogenous proteases, as molecules that may underlie synaptic dysfunction in psychiatric disorders and memory consolidation during sleep. These molecules may provide a therapeutic targets for decreasing strength of reward memories in addiction and traumatic memories in PTSD, as well as restoring deficits in memory consolidation in schizophrenia and aging. We review the evidence for sleep and memory consolidation dysfunction in psychiatric disorders and aging in the context of current evidence pointing to the involvement of extracellular matrix molecules in these processes.

Noise sensitivity associated with nonrestorative sleep in Chinese adults: a cross-sectional study

Background

Nonrestorative sleep is a common sleep disorder with a prevalence ranging from 1.4 to 35%, and is associated with various psychological and physical health issues. Noise exposure and noise sensitivity have been proposed to contribute to nonrestorative sleep. This study aimed to examine the relationships among noise, noise sensitivity, nonrestorative sleep, and physiological sleep parameters in Chinese adults.

Methods

A cross-sectional household survey was conducted with randomly selected Chinese adults based on a frame stratified by geographical districts and types of quarters in Hong Kong. We administered a battery of questionnaires, including the Nonrestorative Sleep Scale, the Weinstein Noise Sensitivity Scale, the ENRICHD Social Support Instrument, the Patient Health Questionnaire, and the Perceived Stress Scale to assess nonrestorative sleep, noise sensitivity, social support, somatic symptoms and stress, respectively. Anxiety and depression were evaluated by the Hospital Anxiety and Depression Scale while sociodemographic and lifestyle characteristics were assessed with an investigator-developed sheet. Nocturnal noise level and physiological sleep parameters were measured during nighttime for a week by noise dosimetry and actigraphy, respectively. A structured multiphase linear regression was conducted to estimate associations.

Results

A total of 500 adults (66.4% female) with an average age of 39 years completed this study. Bivariate regressions showed that age, marital status, occupation, family income, season, exercise, cola and soda consumption, social support, somatic symptoms, stress, depression, noise sensitivity, total sleep time, and awakenings were associated with nonrestorative sleep. In the multivariable analysis, family income, season, exercise, social support, somatic symptoms, stress, and depression remained associated with nonrestorative sleep. Specifically, a one-unit increase of noise sensitivity was associated with 0.08 increase in nonrestorative sleep (95% confidence interval [CI]: 0.01, 0.15, p = 0.023). Nocturnal noise was negatively associated with time in bed (b = − 1.65, 95% CI: − 2.77, − 0.52, p = 0.004), total sleep time (b = − 1.61, 95% CI: − 2.59, − 0.62, p = 0.001), and awakenings (b = − 0.16, 95% CI: − 0.30, − 0.03, p = 0.018), but was not associated with nonrestorative sleep.

Conclusions

Nonrestorative sleep was predicted by noise sensitivity in addition to family income, season, exercise, social support, somatic symptoms, stress, and depression.

Mealtime care and dietary intake in older psychiatric hospital inpatient: A multiple case study

AIMS

To investigate the energy and protein adequacy of meals and dietary intake of older psychiatric inpatients and describe patient and mealtime factors potentially influencing intake.

DESIGN

Multiple case studies.

METHODS

Psychiatric inpatients aged 65 years and older, admitted to a single mental health ward during the 6-week study period (April-May 2019) were eligible for inclusion. Dietary intake was observed for two consecutive days each week (minimum four observation days). Visual plate waste methods were used to estimate patients' dietary intake at mealtimes, with energy and protein intake calculated using known food composition data and compared with estimated requirements. Medical records were reviewed weekly to collect information on potential factors related to intake and mealtime care. Data from all sources were first summarized in a case record for within-case analysis using descriptive statistics, followed by cross-case analysis.

RESULTS

Eight participants (five men, age 67-90 years, two underweight and one overweight, and four requiring some mealtime assistance) had 5-12 days of observation data recorded. Three met their estimated daily energy and protein requirements throughout the study period, while the remaining five participants did not. The main barriers identified as contributing to insufficient energy and protein intake were as follows: missing meals (asleep and treatment); inadequate food provided (insufficiency of the standard hospital menu); and need for increased mealtime assistance.

CONCLUSION

Poor dietary intake may be common among older psychiatric patients, suggesting that they may also need nursing and multidisciplinary nutrition care interventions shown to effectively prevent and treat malnutrition in other older inpatient groups.

IMPACT

Older psychiatric patients experience similar nutrition and mealtime issues to other older inpatients. This study highlights the need for nurses and the multidisciplinary team to ensure patients order and receive adequate food, especially when they miss meals and that they receive proactive mealtime assistance.

Acute blockade of NR2C/D subunit-containing N-methyl-D-aspartate receptors modifies sleep and neural oscillations in mice

N-methyl-d-aspartate receptors (NMDARs) play an important role in excitatory neurotransmission and have been associated with psychiatric conditions including schizophrenia and major depressive disorder. NMDARs are composed of two NR1 and two NR2 subunits. The type of NR2 subunit determines electrophysiological and pharmacological properties of the receptor. As the precise role of NR2C/D subunit-containing NMDARs is poorly understood in vivo, we have performed behavioural, quantitative electroencephalographic (qEEG) and polysomnographic analysis following acute pharmacological blockade of these receptor subtypes in adult male CD1 mice. We found that NR2C/D blockade impaired motor coordination and decreased the amount of gross movement. Moreover, EEG power in multiple frequency bands including theta and sigma were found to decrease significantly together with a decrease of theta oscillation frequency. Changes of these qEEG measures were accompanied by a decrease in time spent in slow-wave and rapid eye movement sleep, but an increase of time spent in quiet wakefulness. Furthermore, there was a significant decrease of sleep spindle oscillation density. These findings highlight the importance of NR2C/D-containing NMDARs and take a step towards establishing a link between electrophysiological correlates of psychiatric disorders and underlying synaptic dysfunctions.

Modulation of Slow-Wave Sleep: Implications for Psychiatry

PURPOSE OF REVIEW

The objectives of this review are to examine and integrate existing empirical evidence regarding the impact of slow-wave sleep (SWS) modulation on memory and executive function performance in individuals with psychiatric disorders, and to examine the feasibility of integrating SWS modulation into psychiatric care.

RECENT FINDINGS

SWS modulation in individuals with psychiatric disorders resulted in changes to SWS across multiple psychiatric disorders, using all stimulation methods. SWS stimulation was associated with improved cognitive performance. SWS modulation using acoustic stimulation resulted in improved cognitive performance in children with ADHD, and the use of transcranial stimulation was associated with improved cognitive performance in individuals with mild cognitive impairment. Significant relationships between changes in SWS and cognitive improvement were found for individual with mild cognitive impairment following the use of acoustic or transcranial stimulation night. Our review reveals partial support to the potential efficacy of SWS modulation as a transdiagnostic intervention that uses sleep to improve cognitive functions of individuals diagnosed with psychiatric disorders and cognitive deficits. It further highlights multiple barriers pertaining to the feasibility of integrating SWS modulation into clinical practice and proposes ways to improve it.

Comparing two measures of sleep depth/intensity

Study Objectives

To compare delta spectral power (delta) and odds ratio product (ORP) as measures of sleep depth during sleep restriction with placebo or a drug that increases delta.

Methods

This is a secondary analysis of data from a study of 41 healthy participants randomized to receive placebo or gaboxadol 15 mg during sleep restriction. Participants underwent in-laboratory sleep studies on two baseline, four sleep restriction (5-h), and two recovery nights. Relation between delta or ORP and sleep depth was operationally defined as the degree of association of each metric to the probability of arousal or awakening occurring during the next 30 s (arousability).

Results

ORP values in wake, N1, N2, N3, and REM were significantly different. Delta differed between both N2 and N3 and other sleep stages but not between wake and N1 or N1 and REM. Epoch-by-epoch and individual correlations between ORP and delta power were modest or insignificant. The relation between ORP and arousability was linear across the entire ORP range. Delta also changed with arousability but only when delta values were less than 300 μV2. Receiver-operating-characteristic analysis found the ability to predict imminent arousal to be significantly greater with ORP than with log delta power for all experimental conditions. Changes in ORP, but not log delta, across the night correlated with next-day physiologic sleep tendency.

Conclusions

Compared to delta power, ORP is more discriminating among sleep stages, more sensitive to sleep restriction, and more closely associated with arousability. This evidence supports ORP as a measure of sleep depth/intensity.

High-frequency cardiopulmonary coupling during sleep correlates with memory in depressed patients: A pilot study

BACKGROUND

It has been demonstrated that a reduction in the amount of high-frequency cardiopulmonary coupling (CPC) is indicative of unstable sleep in unmedicated patients with major depressive disorder (MDD). Considering the close relationship between sleep quality and memory consolidation, this study sought to investigate the potential of high-frequency CPC as a novel biomarker for objective evaluation of memory impairment in MDD.

METHODS

A total of 64 depressed patients and 35 healthy controls were included in this cross-sectional study. High-frequency coupling (HFC) was assessed by electrocardiogram-based CPC analysis using a portable sleep-respiration monitor during sleep for one night. The next day, subjects completed the cognition assessment with the Assessment of Neuropsychological Status (RBANS). The 17-Item Hamilton Depression Rating Scale (HAMD₁₇) and the Hamilton Rating Scales for Anxiety (HAMA) were used to evaluate the severity of depression and anxiety in each patient, respectively.

RESULTS

There was no significant difference in the proportion of HFC between depressed patients and healthy controls. In patients with low HFC proportion (<35%), severe anxiety could significantly decrease HFC proportion. The HFC proportion positively correlated with immediate and delayed memory in depressed patients. Further analysis showed that patients with low HFC proportion may have worse delayed memory.

LIMITATIONS

The lack of prior exposure to the monitoring equipment and procedure could have generated artefacts that would have disappeared after habituation.

CONCLUSIONS

These results support a positive correlation between the HFC proportion and memory in depressed patients. Further research is required to explore the clinical implications of these findings.

Increased Awakenings From Non-rapid Eye Movement Sleep Explain Differences in Dream Recall Frequency in Healthy Individuals

Background

Dreaming is a universal experience, yet there is considerable inter-individual variability in dream recall frequency (DRF). One dominant model, the “arousal-retrieval” model, posits that intra-sleep wakefulness is required for dream traces to be encoded into long-term storage, essentially proposing that a better memory for dreams underlie increased DRF. A recent study utilizing polysomnography combined with an event-related potentials paradigm, provides direct support for this model by demonstrating increased intra-sleep wakefulness in a healthy population by comparing high frequency recallers (HFRs) and low frequency recallers (LFRs). Another study by the same group demonstrated increased regional cerebral blood flow in regions associated with dream production, supporting the premise that HFRs also may produce more dreams.

Hypotheses

This study investigated the profile of nocturnal awakenings and dream production in healthy HFRs and LFRs. Hypothesis (1a): HFRs will spend significantly more time awake after sleep onset; (1b): HFRs will experience significantly more awakenings across the night, and from rapid eye movement (REM) sleep in particular; (2) HFRs will have significantly higher rates of dream production across the night as measured by REM density.

Methods

We studied two groups of healthy adults: HFRs (n = 19) and LFRs (n = 17) who underwent polysomnographic recordings on two non-consecutive nights.

Results

Hypothesis (1a) was confirmed: HFRs spent significantly more time awake after sleep onset. Hypothesis (1b) was partially confirmed: HFRs experienced significantly more awakenings across the night; however, awakenings from REM sleep were comparable. Interestingly, HFRs had significantly more awakenings, as well as a higher number of longer awakenings, from non-rapid eye movement (NREM) stage 2 sleep. Hypothesis (2) was not confirmed: There was no significant difference in rates of REM density between groups.

Conclusion

This is the first study to provide evidence that awakenings from NREM 2 sleep might underlie increased DRF in HFRs. This finding coupled with null findings in relation to REM sleep variables, support the premise that inter-individual variability in DRF cannot be ascribed to differences in REM sleep parameters in healthy individuals. Instead, the data indicates that awakenings from NREM sleep is of particular importance in relation to DRF in a healthy population.

Effects of 3 Weeks of Water Immersion and Restraint Stress on Sleep in Mice

Repeated stress is a risk factor for mental disorders and can also lead to sleep disturbances. Although the effects of stress on sleep architecture have been investigated in rodents, the length of the stress exposure period in most studies has been limited to about 10 days, and few studies have analyzed the effects of chronic stress over a longer period. Here we investigated how sleep is affected in a mouse model of depression induced by 3 weeks of daily water immersion and restraint stress (WIRS). Sleep was recorded after 1, 2, and 3 weeks of stress exposure. Some stress-induced changes in several sleep measures were maintained across the 3 weeks, whereas other changes were most prominent during the 1st week. The total amount of non-rapid eye movement sleep (NREMS) was increased and the total amount of time spent awake was decreased across all 3 weeks. On the other hand, the amount of REMS during the dark phase was significantly increased in the 1st week compared with that at baseline or the 2nd and 3rd weeks. Electroencephalogram (EEG) power in the delta range was decreased during NREMS, although the total amount of NREMS was increased. These findings indicate that repeated WIRS, which eventually leads to a depression-like phenotype, differentially affects sleep between the early and subsequent periods. The increase in the amount of REMS during the dark phase in the 1st week significantly correlated with changes in body weight. Our results show how sleep changes throughout a long period of chronic stress in a mouse model of depression.

Individual Correlates of Sleep Among Childbearing Age Women in Canada

Objective/Background: Women of childbearing age (WOCBA) may be at high risk for short or poor sleep. Yet few studies have focused on this population. The study objective was to identify individual correlates of sleep duration and quality among WOCBA. Participants: The sample consisted of 9,749 WOCBA aged 18-44 years from the Canadian Community Health Survey 2011-2014. Methods: All variables were self-reported. Sleep duration was dichotomized as insufficient (< 7 hr/night) or adequate (≥ 7 hr/night). A composite score of sleep quality was dichotomized as having sleeping problems none/little or some/most/all the time. Age, ethnicity, level of education, household income, mood disorders, parity, geographical location, fruit and vegetable (FV) intake, physical activity, smoking and alcohol consumption were tested as correlates of sleep duration or quality using hierarchical logistic regression. Results: Ethnicity, parity, geographical location and smoking were correlates of sleep duration; this model discriminated 56.9% of WOCBA. Ethnic minorities, WOCBA with many children, living in urban areas and smoking were associated with lower odds of having adequate sleep duration. Ethnicity, level of education, mood disorders, geographical location, FV intake, and alcohol consumption were correlates of sleep quality; this model discriminated 59.0% of WOCBA. Ethnic minorities, lower level of education, mood disorders, living in urban areas, low FV intake, and alcohol consumption were associated with lower odds of having quality sleep. Conclusions: Some WOCBA may be more at risk for short or poor sleep based on their demographics and health behaviors. This can be used to identify which WOCBA are most in need of sleep interventions.

Actigraphy for evaluation of mood disorders: A systematic review and meta-analysis

BACKGROUND

Actigraphy has enabled consecutive observation of individual health conditions such as sleep or daily activity. This study aimed to examine the usefulness of actigraphy in evaluating depressive and/or bipolar disorder symptoms.

METHOD

A systematic review and meta-analysis was conducted. We selected studies that used actigraphy to compare either patients vs. healthy controls, or pre- vs. post-treatment data from the same patient group. Common actigraphy measurements, namely daily activity and sleep-related data, were extracted and synthesized.

RESULTS

Thirty-eight studies (n = 3,758) were included in the analysis. Compared with healthy controls, depressive patients were less active (standardized mean difference; SMD=1.27, 95%CI=[0.97, 1.57], P<0.001) and had longer wake after sleep onset (SMD= - 0.729, 95%CI=[- 1.20, - 0.25], p = 0.003). Total sleep time (SMD= - 0.33, 95%CI=[- 0.55, - 0.11], P = 0.004), sleep latency (SMD= - 0.22, 95%CI=[- 0.42, - 0.02], P = 0.032), and wake after sleep onset (SMD= - 0.22, 95%CI=[- 0.39, - 0.04], P = 0.015) were longer in euthymic/remitted patients compared to healthy controls. In pre- and post-treatment comparisons, sleep latency (SMD=- 0.85, 95%CI=[- 1.53, - 0.17], P = 0.015), wake after sleep onset (SMD= - 0.65, 95%CI=[- 1.20, - 0.10], P = 0.022), and sleep efficiency (SMD=0.77, 95%CI=[0.29, 1.24], P = 0.002) showed significant improvement.

LIMITATION

The sample sizes for each outcome were small. The type of actigraphy devices and patients' illness severity differed across studies. It is possible that hospitalizations and medication influenced the outcomes.

CONCLUSION

We found significant differences between healthy controls and mood disorders patients for some actigraphy-measured modalities. Specific measurement patterns characterizing each mood disorder/status were also found. Additional actigraphy data linked to severity and/or treatment could enhance the clinical utility of actigraphy.

Sleep disturbance in individuals with physical disabilities and chronic pain: The role of physical, emotional and cognitive factors

BACKGROUND

Sleep problems are common for individuals living with physical disabilities and chronic pain. However, the factors that influence the relationship between pain and sleep problems in these populations remain unknown.

OBJECTIVE

The aim of this study was to increase our understanding of the physical, emotional and cognitive factors associated with sleep disturbance in individuals with chronic health conditions often associated with physical disabilities.

METHODS

Participants were recruited from a database of individuals with a variety of chronic health conditions, including multiple sclerosis, spinal cord injury, back pain, osteoarthritis, and amputations. To participate in the study, they needed to report having a chronic pain problem. Participants completed an online survey using REDCap assessing average pain intensity (Numerical Rating Scale-11), pain extent (number of painful body areas), sleep disturbance (PROMIS Sleep Disturbance), depression (PROMIS Emotional Distress-Depression) and catastrophizing (Coping Strategies Questionnaire). A total of 455 participants (M_age = 58.9; SD = 11.4), of which 292 (64%) were women, provided complete data. We performed a series of four regression analyses.

RESULTS

After controlling for age and sex, the predictors explained an additional 7-16% of the variance in sleep disturbance. The final model with all of the predictors explained 22%.

CONCLUSIONS

Consistent with the study hypothesis, all the variables examined made significant and independent contributions to the variance in sleep disturbance. The findings provide additional evidence that physical, emotional and cognitive factors all play a role in the sleep quality of individuals with chronic health conditions often associated with physical disabilities.

Gαs-coupled receptor signaling and sleep regulate integrin activation of human antigen-specific T cells

This study demonstrates a regulatory role of Gα_s-coupled receptor agonists (catecholamines, prostaglandins, and adenosine) and sleep on integrin activation on T cells in humans. The findings point to a mechanism by which T cell responses are altered in several conditions characterized by aberrant levels of these substances.

Efficient T cell responses require the firm adhesion of T cells to their targets, e.g., virus-infected cells, which depends on T cell receptor (TCR)–mediated activation of β₂-integrins. Gα_s-coupled receptor agonists are known to have immunosuppressive effects, but their impact on TCR-mediated integrin activation is unknown. Using multimers of peptide major histocompatibility complex molecules (pMHC) and of ICAM-1—the ligand of β₂-integrins—we show that the Gα_s-coupled receptor agonists isoproterenol, epinephrine, norepinephrine, prostaglandin (PG) E₂, PGD₂, and adenosine strongly inhibit integrin activation on human CMV- and EBV-specific CD8⁺ T cells in a dose-dependent manner. In contrast, sleep, a natural condition of low levels of Gα_s-coupled receptor agonists, up-regulates integrin activation compared with nocturnal wakefulness, a mechanism possibly underlying some of the immune-supportive effects of sleep. The findings are also relevant for several pathologies associated with increased levels of Gα_s-coupled receptor agonists (e.g., tumor growth, malaria, hypoxia, stress, and sleep disturbances).

Preliminary evidence that vortioxetine may improve sleep quality in depressed patients with insomnia: a retrospective questionnaire analysis

Insomnia is a frequent symptom in depressed patients. It can present with difficulty in initiating and/or maintaining sleep. We retrospectively evaluated a group of 15 patients affected by major depressive disorder and complaining of insomnia, who started vortioxetine (VOR) treatment for their depressive symptoms. The following questionnaires were captured at baseline and follow-up: Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale and Beck Depression Inventory. Pittsburgh Sleep Quality Index total score significantly decreased between follow-up and baseline (P < 0.01), and in several subitems related to sleep quality and continuity. Moreover, Epworth Sleepiness Scale decreased between follow-up and baseline (P < 0.01). Finally, Beck Depression Inventory reduction was also evident between follow-up and baseline (P < 0.01). This retrospective analysis showing the significant effect of VOR on both depressive symptoms and insomnia in patients showing comorbid major depressive disorder and insomnia invites further research in order to confirm this preliminary evidence. We hypothesize that the VOR mechanism of action may explain the improvement of subjective sleep, other than depressive symptoms.

Changes in brain arousal (EEG-vigilance) after therapeutic sleep deprivation in depressive patients and healthy controls

Depressed patients frequently exhibit a hyperstable brain arousal regulation. According to the arousal regulation model of affective disorders, the antidepressant effect of therapeutic sleep deprivation could be achieved by counter-acting this dysregulation. We investigated the impact of partial sleep deprivation (PSD) on EEG-vigilance (an indicator of brain arousal regulation) in depressed patients (n = 27) and healthy controls (n = 16). PSD was hypothesized to cause a more prominent destabilisation of brain arousal regulation in depressed patients (reflected by increased occurrence of lower EEG-vigilance stages). Furthermore, it was studied whether responders (n = 17) exhibit a more stable baseline brain arousal regulation and would show a more prominent arousal destabilisation after PSD than non-responders (n = 10). Before PSD, patients showed a more stable EEG-vigilance with less declines to lower vigilance stages compared to controls. Contrary to the hypothesis, a greater destabilisation of brain arousal after PSD was seen in controls. Within the patient sample, responders generally showed a less stable EEG-vigilance, especially after PSD when we found significant differences compared to non-responders. EEG-vigilance in non-responders showed only little change from baseline to after PSD. In summary, PSD had a destabilizing impact on brain arousal regulation in healthy controls whereas depressed patients reacted heterogeneously depending on the outcome of treatment.

Sleep patterns deteriorate over time in chronic corticosterone-treated rats

Repeated corticosterone (CORT) injections reliably produce depressive-like behavior in rodents. Our previous study showed that sleep parameters were altered in rats after daily injections of CORT for 7 days, and sleep disturbances appeared to be correlated with depressive-like behavior. The aim of the present study was to investigate time-dependent correlations between changes in sleep parameters and the formation of depressive-like behavior in rats after more prolonged treatment with CORT. Rats received daily injections of CORT (40 mg/kg, s.c.) for 7, 14, or 21 days. Electroencephalographic recordings were performed to study sleep parameters. The sucrose preference test and forced swim test were performed to evaluate depressive-like behavior. Western blot was used to detect protein levels. Our results showed that 7-day CORT treatment resulted in no significant depressive-like behavior or changes in rapid-eye-movement (REM) sleep. However, the duration of non-REM sleep significantly decreased, tyrosine hydroxylase (TH) levels significantly increased, and glucocorticoid receptor (GR) expression decreased in the locus coeruleus. Treatment with CORT for 14 and 21 days increased depressive-like behavior, enhanced REM sleep, shortened REM sleep latency, decreased TH and GR levels, and increased the levels of the chaperone FK506 binding protein 51 (FKBP51) in the locus coeruleus. These results indicate that the development of depression after chronic CORT treatment may be related to the formation of sleep disorders. Abnormalities of REM sleep may be a characteristic of sleep in models of depression that is induced by chronic CORT administration in rats. The noradrenergic system and GR pathway in the locus coeruleus may be involved in the formation of depression concomitant with sleep disturbances.

Differences in sleep functioning between individuals with seasonal affective disorder and major depressive disorder in Finland

BACKGROUND

Sleep problems are commonly reported in seasonal affective disorder (SAD) and major depressive disorder (MDD). However, the specific characteristics of sleep difficulties differ. Frequent sleep problems in MDD are insomnia and night awakenings, whereas SAD patients complain of hypersomnia and daytime sleepiness. No previous studies have reported differences in sleep functioning between these two disorders.

METHODS

We interviewed 4554 subjects from the Health 2011 survey and included 4153 individuals in this study. We selected participants who fulfilled the criteria for SAD (n = 223), nonseasonal-MDD (n = 238), SAD + MDD (n = 65), and controls (n = 3627). They completed the World Health Organization Composite International Diagnostic Interview, Munich version (M-CIDI), the Seasonal Pattern Assessment Questionnaire (SPAQ), The Beck Depression Inventory (BDI), the EuroQoL (EQ-5), the Alcohol Use Disorders Identification Test (AUDIT) and several questions about sleeping, based on the Basic Nordic Sleep Questionnaire (BNSQ).

RESULTS

We found Significant differences between groups for "enough sleep", "breathing interruptions during sleep", "tiredness during the day", and "sleeping difficulties". Controls reported better functioning in all sleep variables. SAD + MDD individuals showed more problems in "enough sleep" than SAD, more "breathing interruptions during sleep" than SAD and nonseasonal-MDD, felt more "tired during the day" than SAD and nonseasonal-MDD, and reported more "sleeping difficulties" than SAD and nonseasonal-MDD. Finally, nonseasonal-MDD individuals felt more "tired during the day" than SAD.

CONCLUSION

Individuals with SAD + MDD show generalized sleeping problems. However, when SAD and nonseasonal-MDD appear separately, similar sleep functioning is observed. Nonseasonal-MDD subjects report to be more tired during the day than SAD.

Neuropeptidomics of the Rat Habenular Nuclei

Conserved across vertebrates, the habenular nuclei are a pair of small symmetrical structures in the epithalamus. The nuclei functionally link the forebrain and midbrain by receiving input from and projecting to several brain regions. Each habenular nucleus comprises two major asymmetrical subnuclei, the medial and lateral habenula. These subnuclei are associated with different physiological processes and disorders, such as depression, nicotine addiction, and encoding aversive stimuli or omitting expected rewarding stimuli. Elucidating the functions of the habenular nuclei at the molecular level requires knowledge of their neuropeptide complement. In this work, three mass spectrometry (MS) techniques-liquid chromatography (LC) coupled to Orbitrap tandem MS (MS/MS), LC coupled to Fourier transform (FT)-ion cyclotron resonance (ICR) MS/MS, and matrix-assisted laser desorption/ionization (MALDI) FT-ICR MS-were used to uncover the neuropeptide profiles of the rodent medial and lateral habenula. With the assistance of tissue stabilization and bioinformatics, a total of 262 and 177 neuropeptides produced from 27 and 20 prohormones were detected and identified from the medial and lateral habenula regions, respectively. Among these neuropeptides, 136 were exclusively found in the medial habenula, and 51 were exclusively expressed in the lateral habenula. Additionally, novel sites of sulfation, a rare post-translational modification, on the secretogranin I prohormone are identified. The results demonstrate that these two small brain nuclei have a rich and differentiated peptide repertoire, with this information enabling a range of follow-up studies.

Sleep quality of endometrial cancer survivors and the effect of treatments

Objective:

Sleep disorders affect 54.9% of gynaecologic cancer survivors. The effect of treatment methods on sleep quality is not clear. This study evaluated the sleep quality of survivors of endometrial cancer and compared the effects of different treatments on sleep quality.

Materials and Methods:

Patients were categorised as surgery (group 1), surgery + brachytherapy (BRT) (group 2), surgery + external beam radiation therapy (EBRT) (group 3), and surgery + EBRT + BRT + chemotherapy (group 4). Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) questionnaire. The PSQI was completed by the participants before surgery, 1, 3, and 6 months after each treatment was completed. The PSQI scores were compared between the different measurement times and different study groups.

Results:

This study enrolled 114 patients with a mean age of 58.1±11 years. The number of participants in each group was 53 (46.5%), 14 (12.3%), 12 (10.5%), and 35 (30.7%), respectively. At baseline, 28 (24.6%) patients reported poor sleep quality. The mean PSQI score reached the maximum level at the second measurement and decreased slightly during follow-up and the change in the PSQI score was significant (p=0.001). Group 3 and group 4 had significantly higher scores from baseline (p<0.008). At time point 3, the differences between the groups were significant. At time point 4, the most prominent effect of treatment on sleep quality was observed in patients with combined chemo-radiotherapy when compared with the other study groups.

Conclusion:

Most survivors of endometrial cancer are affected by poor sleep quality during their treatment. To improve these patients’ quality of life, this disorder must be considered at each visit and tailored care plans should be developed to meet the women’s needs. Further studies are needed to evaluate the long-term results of sleep quality on patients with endometrial cancer.

Depressive symptoms are associated with poor sleep quality rather than apnea-hypopnea index or hypoxia during sleep in patients with obstructive sleep apnea

PURPOSE

We examined factors, including the severity of obstructive sleep apnea (OSA), that were associated with depressive symptoms and excessive daytime sleepiness in OSA patients.

METHODS

We retrospectively reviewed data of 1203 subjects (861 men, mean age 48.2 years) who completed self-reported questionnaires and underwent polysomnography between September 2005 and May 2016 at the Center for Sleep and Chronobiology at Seoul National University Hospital. We compared scores on the Beck Depression Inventory (BDI) and Epworth sleepiness scale (ESS) between OSA and control groups. Analyses for OSA subgroups were classified by severity, and partial correlations were performed.

RESULTS

BDI scores were higher in the OSA than in the control group (12.3 ± 7.6 vs. 10.1 ± 6.2, p = 0.001). There were differences in ESS scores among the mild, moderate, and severe OSA subgroups (p < 0.001), but not in BDI scores (p = 0.236). After adjusting for age, gender, and BMI, BDI in the OSA group correlated positively with wake after sleep onset (WASO; p = 0.014) and sleep latency (SL; p < 0.001), negatively with total sleep time (TST; p < 0.001) and sleep efficiency (SE; p = 0.001), but not with the apnea-hypopnea index (AHI; p = 0.387) or average O₂ (p = 0.542). ESS in the OSA group correlated positively with TST (p < 0.001), SE (p < 0.001), and AHI (p < 0.001) and negatively with WASO (p = 0.010), SL (p < 0.001), and average O₂ (p < 0.001).

CONCLUSIONS

In this study, patients with OSA had more depressive symptoms than those without OSA. Daytime sleepiness in OSA patients was related to the severity of OSA as well as sleep propensity. However, depressive symptoms in OSA patients were associated with poor sleep quality rather than OSA severity. Depressive symptoms in OSA may be treated by modulating the sleep architecture and sleep quality.

Effects of Chronic Social Defeat Stress on Sleep and Circadian Rhythms Are Mitigated by Kappa-Opioid Receptor Antagonism

Stress plays a critical role in the neurobiology of mood and anxiety disorders. Sleep and circadian rhythms are affected in many of these conditions. Here we examined the effects of chronic social defeat stress (CSDS), an ethological form of stress, on sleep and circadian rhythms. We exposed male mice implanted with wireless telemetry transmitters to a 10 day CSDS regimen known to produce anhedonia (a depressive-like effect) and social avoidance (an anxiety-like effect). EEG, EMG, body temperature, and locomotor activity data were collected continuously during the CSDS regimen and a 5 day recovery period. CSDS affected numerous endpoints, including paradoxical sleep (PS) and slow-wave sleep (SWS), as well as the circadian rhythmicity of body temperature and locomotor activity. The magnitude of the effects increased with repeated stress, and some changes (PS bouts, SWS time, body temperature, locomotor activity) persisted after the CSDS regimen had ended. CSDS also altered mRNA levels of the circadian rhythm-related gene mPer2 within brain areas that regulate motivation and emotion. Administration of the κ-opioid receptor (KOR) antagonist JDTic (30 mg/kg, i.p.) before CSDS reduced stress effects on both sleep and circadian rhythms, or hastened their recovery, and attenuated changes in mPer2 Our findings show that CSDS produces persistent disruptions in sleep and circadian rhythmicity, mimicking attributes of stress-related conditions as they appear in humans. The ability of KOR antagonists to mitigate these disruptions is consistent with previously reported antistress effects. Studying homologous endpoints across species may facilitate the development of improved treatments for psychiatric illness.SIGNIFICANCE STATEMENT Stress plays a critical role in the neurobiology of mood and anxiety disorders. We show that chronic social defeat stress in mice produces progressive alterations in sleep and circadian rhythms that resemble features of depression as it appears in humans. Whereas some of these alterations recover quickly upon cessation of stress, others persist. Administration of a kappa-opioid receptor (KOR) antagonist reduced stress effects or hastened recovery, consistent with the previously reported antistress effects of this class of agents. Use of endpoints, such as sleep and circadian rhythm, that are homologous across species will facilitate the implementation of translational studies that better predict clinical outcomes in humans, improve the success of clinical trials, and facilitate the development of more effective therapeutics.

Physical Activity Modulates Common Neuroplasticity Substrates in Major Depressive and Bipolar Disorder

Mood disorders (MDs) are chronic, recurrent mental diseases that affect millions of individuals worldwide. Although the biogenic amine model has provided some clinical utility, a need remains to better understand the interrelated mechanisms that contribute to neuroplasticity deficits in MDs and the means by which various therapeutics mitigate them. Of those therapeutics being investigated, physical activity (PA) has shown clear and consistent promise. Accordingly, the aims of this review are to (1) explicate key modulators, processes, and interactions that impinge upon multiple susceptibility points to effectuate neuroplasticity deficits in MDs; (2) explore the putative mechanisms by which PA mitigates these features; (3) review protocols used to induce the positive effects of PA in MDs; and (4) highlight implications for clinicians and researchers.

Subjective sleep quality and sleep duration of patients in a psychiatric hospital

Sleep complaints and sleep disturbances are highly prevalent in patients with psychiatric disorders. During hospitalization the patients’ condition may be even worse but little is known about the subjective sleep quality in psychiatric hospitals. Thus, we have investigated subjective sleep quality and mean sleep duration in patients with different psychiatric disorders at the end of hospitalization. For a period of one year, inpatients of a psychiatric hospital with diagnosis of substance use disorder (SUD), schizophrenia (SCZ), or anxiety/depressive disorders (AND) were routinely asked to fill in an easily comprehensible sleep quality questionnaire at the end of their hospitalization. Age, gender, subjective sleep quality, and sleep duration were analyzed; sleep duration was classified according to age-specific recommendations. Data of n=309 patients (age 52.1±17.9y, 56.1% women) were analyzed (n=63 SUD, n=50 SCZ, n=196 AND). Mean sleep duration was 7.0±2.0 h; 20.7% of patients had sleep durations below and 4.5% above age-specific recommendations. Non-restorative sleep during hospitalization was reported “almost always” in 38.2% (n=118), and “occasionally” in 30.1% (n=93). Subjective sleep quality was significantly associated with sleep duration (r_s=−0.31, P<0.0005), but not with age, gender or diagnostic subgroup. The study showed that a great proportion of patients reported poor subjective sleep quality during hospitalization, regardless of age, gender and psychiatric diagnosis. As sleep quality was significantly associated with short sleep duration, a first step could be to take care to achieve recommended age-specific sleep durations in psychiatric hospitals.

Sleep quality in healthy and mood-disordered persons predicts daily life emotional reactivity

Disordered sleep has been linked to impaired emotional functioning in healthy and depressed individuals. Little is known, however, about how chronic sleep problems influence emotional reactivity in everyday life. Participants with major or minor unipolar depressive disorder (n = 60) and healthy controls (n = 35) reported on sleep and emotional responses to daily life events using a computerised Experience Sampling Method. We examined whether impaired sleep quality influenced emotional reactivity to daily events, and if this relationship was altered by unipolar mood disorders. Among healthy individuals, sleep difficulties were associated with enhanced negative affect (NA) to unpleasant events and a dulled response to neutral events. However, among mood-disordered persons, sleep difficulties were associated with higher NA across all types of everyday life events. Impaired sleep quality differentially affects daily life emotional reactions as a function of depression.