Electroencephalographic sleep profiles in treatment course and long-term outcome of major depression: association with DEX/CRH-test response

EEG-vigilance regulation is associated with and predicts ketamine response in major depressive disorder

Ketamine offers promising new therapeutic options for difficult-to-treat depression. The efficacy of treatment response, including ketamine, has been intricately linked to EEG measures of vigilance. This research investigated the interplay between intravenous ketamine and alterations in brain arousal, quantified through EEG vigilance assessments in two distinct cohorts of depressed patients (original dataset: n = 24; testing dataset: n = 24). Clinical response was defined as a decrease from baseline of >33% on the Montgomery-Åsberg Depression Rating Scale (MADRS) 24 h after infusion. EEG recordings were obtained pre-, start-, end- and 24 h post- infusion, and the resting EEG was automatically scored using the Vigilance Algorithm Leipzig (VIGALL). Relative to placebo (sodium chloride 0.9%), ketamine increased the amount of low-vigilance stage B1 at end-infusion. This increase in B1 was positively related to serum concentrations of ketamine, but not to norketamine, and was independent of clinical response. In contrast, treatment responders showed a distinct EEG pattern characterized by a decrease in high-vigilance stage A1 and an increase in low-vigilance B2/3, regardless of whether placebo or ketamine had been given. Furthermore, pretreatment EEG differed between responders and non-responders with responders showing a higher percentage of stage A1 (53% vs. 21%). The logistic regression fitted on the percent of A1 stages was able to predict treatment outcomes in the testing dataset with an area under the ROC curve of 0.7. Ketamine affects EEG vigilance in a distinct pattern observed only in responders. Consequently, the percentage of pretreatment stage A1 shows significant potential as a predictive biomarker of treatment response.Clinical Trials Registration: https://www.clinicaltrialsregister.eu/ctr-search/trial/2013-000952-17/CZ Registration number: EudraCT Number: 2013-000952-17.

Restless Leg Syndrome in Hemodialysis Patients: A Narrative Review

BACKGROUND

Restless legs syndrome (RLS) is a clinical entity characterized by sensory-motor manifestations commonly observed in end-stage renal illness. Evidence suggests that RLS is a multifactorial phenomenon that can be influenced by many critical factors, including genetic predisposition, dietary patterns, and deficiency in some vitamins. Iron metabolism disorders and metabolic derangements have been generally accepted as predisposing elements in RLS. Furthermore, both pharmacological and neuroimaging studies demonstrated dopamine deficiency and dopamine receptors decrease in basal ganglia during RLS.

REVIEW SUMMARY

A literature search was done in three databases (PubMed, Google Scholar, and Cochrane) to identify the pertinent articles discussing the epidemiology, pathogenesis, and management of RLS in hemodialysis patients. RLS can affect the morbidity and mortality of patients treated with dialysis. It also has significant impacts on the quality of life since it can lead to insomnia, increased fatigue, mental health troubles, and other movement problems. Appropriate measures should be considered in this particular population so to prevent and treat RLS. Many drugs and other nonpharmacological methods have been investigated to attenuate the disease's severity. No treatment, however, could offer long-term effects.

CONCLUSION

Further efforts are still required to improve the understanding of RLS pathogenic trends to find more specific and efficient therapies. A wide range of treatment options is available. However, it can be individualized according to the patients' several factors.

A Prospective Study of the Relationship Between Sleep Quality and Depression in Pregnancy

Objective

Poor sleep and depression are common problems during pregnancy, but there has been little investigation into the association between them. This prospective study aims to examine the relationship between sleep quality and depression during pregnancy.

Methods

Pregnant women under 14 weeks’ gestation attending routine outpatient antenatal care in Singapore’s largest maternity hospital were recruited between 2012 and 2014. Women with multiple pregnancies and deemed at high risk of miscarriage were excluded. Six hundred and forty participants completed the Pittsburgh Sleep Quality Index (PSQI) and Edinburgh Postnatal Depression Scale (EPDS) at the three trimesters during pregnancy.

Results

Mean PSQI score was highest in the third visit, suggesting poorer quality sleep in the late third trimester compared to other trimesters. 15.6% of participants at each time point fulfilled the criteria for antenatal depression according to the EPDS cut-off score > 14. PSQI scores were significantly correlated with EPDS scores, and also prospectively predicted EPDS scores in all three trimesters.

Conclusion

Sleep quality in Singaporean pregnant women was poorest in the third trimester, and was associated with the development of depressive symptoms. With more than 1 in 10 women having antenatal depression, interventions targeting sleep quality might be particularly beneficial.

Poor Sleep and Decision-Making Disturbance Are Associated With Suicidal Ideation in Pre-natal Depression

Although many risk factors for suicidal ideation have been identified, few studies have focused on suicidal ideation and pre-natal depression. The purpose was to investigate the relationship between decision-making (DM) dysfunction and sleep disturbance on suicidal ideation in pre-natal depression. Participants included 100 women in the third trimester of pregnancy, including pregnant women with pre-natal depression who had recent suicidal ideation (n = 30), pre-natal depression without SI (n = 35) and healthy controls (n = 35). The Iowa Gambling Task (IGT) was used to evaluate the DM function and the Pittsburgh Sleep Quality Index (PSQI) was used to assess the sleep index. The Edinburgh Post-natal Depression Scale (EPDS) was used to assess suicidal ideation and the seriousness of depression. Overall, the two groups with pre-natal depression showed worse sleep quality and decreased DM function compared with healthy controls. The pre-natal depression with suicidal ideation group showed a significantly higher score in subjective sleep quality and a lower score in block 5 of IGT than the pre-natal depression without suicidal ideation group. Further correlation analysis showed that suicidal ideation positively correlated with subjective sleep quality, sleep duration, and daytime function, and negatively correlated with IGT scores. Sleep disturbance and impaired DM function may be risk factors for suicidal ideation in pre-natal depression.

Associations between Self-Reported Daily Affect Ratings and Sleep Duration during the First Two Weeks of Antidepressant Therapy

Background: In the context of a randomized controlled trial evaluating the efficacy of augmenting fluoxetine treatment in young adults with major depressive disorder (MDD) using a modified repeated partial sleep deprivation protocol contrasting 2 weeks of restricted time in bed (i.e., 6 h TIB) to no time in bed restriction (i.e., 8 h TIB) the study examines whether sleep duration and the timing of repeated partial sleep deprivation predicts patient-reported affect ratings. Participants: Participants included 58 young adults with DSM-IV-diagnosed MDD. Methods: Daily ratings of affect and sleep were collected during the first 2 weeks of initiating fluoxetine treatment, yielding 630 person-days. Actigraphy monitoring was employed to assess compliance with time in bed condition. Results: Negative affect ratings and positivity ratios in the morning were more improved among participants assigned to the 6 h TIB condition compared to the 8 h TIB group. Participants whose bedtime was delayed by 2-h nightly demonstrated the most significant improvement in negative affect and positivity ratio during the first 2 weeks of fluoxetine therapy. Moreover, the trajectory of morning negative affect ratings in the first 2 weeks was predictive of remission after 4 weeks of fluoxetine therapy. Conclusions: These findings suggest that monitoring changes in daily affect may be a valuable marker of early treatment response in young adults with MDD.

A study on sleep apnea in patients with abnormal sewda type of depression

Objective: To preliminarily investigate the clinical features and PSG in abnormal sewda-type depressive insomnia.

Methods: A total of 127 abnormal sewda-type depressive insomnia patients were evaluated with overnight PSG, and 32 normal participants were compared.

Results: Patients with abnormal sewda-type depressive insomnia were compared with the control group; the sleep symptoms showed a long incubation period of sleep, low sleep maintenance rate, low sleep efficiency and poor sleep quality as well as daytime dysfunction. At process and continuity of sleep: Total sleep time, sleep efficiency, sleep maintenance rate in abnormal sewda-type depressive insomnia group were shorter than the control group. Wake after sleep onset, and sleep latency were longer than the control group. At sleep structure: N1 ratio and N2 ratio in depressive insomnia group were longer than the control group, N3 ratio and REM sleep ratio shorter than the control group. At REM index: REM latency, REM cycles, and REM sleep time were shorter than the control group.

Conclusion: Insomnia symptoms in abnormal sewda-type depression comorbid insomnia patients were similar to the ordinary insomnia patients. The PSG characteristics had significant changes in sleep process, sleep structure and REM indicators. The severity of the abnormal sewda-type depression was closely related to REM indicators. Change of REM sleep characteristics may be the specificity, and these could be taken as reference in diagnosis and identification of abnormal sewda-type depressive insomnia.

Better Objective Sleep Was Associated with Better Subjective Sleep and Physical Activity; Results from an Exploratory Study under Naturalistic Conditions among Persons with Multiple Sclerosis

Persons with multiple sclerosis (PwMS) often complain about sleep problems. There is less known about objective sleep-electroencephalography (EEG) dimensions within naturalistic conditions (i.e., home and/or familiar setting). The present cross-sectional study examined the associations between objective and subjective sleep, depression, physical activity scores, and MS-related information among PwMS in their familiar setting. The sample consisted of 16 PwMS (mean age: 50.3 years; median Expanded Disability Status Scale (EDSS): 5.5) who completed questionnaires covering subjective sleep (symptoms of insomnia, restless legs syndrome (RLS) and sleep-disordered breathing), as well as daytime sleepiness, subjective physical activity, depression, and MS-related information (fatigue, EDSS; disease-modifying treatments). Objective sleep was assessed with a mobile sleep-EEG device under naturalist conditions within the home. Descriptively, better objective sleep patterns were associated with lower sleep complaints (r_s = −0.51) and daytime sleepiness (r_s = −0.43), and with lower symptoms of RLS (r_s = −0.35), but not with sleep-disordered breathing (r_s = −0.17). More deep sleep was associated with higher moderate physical activity levels (r_s = 0.56). Objective sleep parameters were not associated with vigorous physical activity levels (r_s < 0.25). Descriptively, moderate and vigorous physical activity scores were associated with lower symptoms of RLS (r_s = −0.43 to −0.47). Results from this small study carried out under naturalistic conditions suggest that among PwMS, better objective sleep correlated with better subjective sleep and higher moderate physical activity levels.

Associations Between Morning Salivary and Blood Cortisol Concentrations in Individuals With Obstructive Sleep Apnea Syndrome: A Meta-Analysis

BACKGROUND

Obstructive sleep apnea syndrome (OSAS) may be associated with an increase in hypothalamic-pituitary-adrenocortical axis activity (HPA AA). We reviewed research comparing morning salivary and blood (serum and plasma) cortisol concentrations of individuals with OSAS to those of healthy controls.

METHODS

We made a systematic search without any restrictions of the PubMed/Medline, Scopus, Cochrane Library, and Web of Science databases for relevant articles published up to August 25, 2019.

RESULTS

Sixteen studies were analyzed in this meta-analysis; five studies compared morning salivary concentrations, five compared serum concentrations, four compared plasma cortisol concentrations, and two compared both salivary and plasma concentrations. In pediatric samples, compared to healthy controls, those with OSAS had significantly lower saliva morning cortisol concentrations (MD = -0.13 µg/dl; 95% CI: 0.21, -0.04; P = 0.003). In contrast, no significant differences were observed for serum cortisol concentrations, plasma cortisol concentrations, or salivary morning cortisol concentrations between adults with and without OSAS (p = 0.61, p = 0.17, p = 0.17).

CONCLUSION

Cortisol concentrations did not differ between adults with OSAS and healthy controls. In contrast, morning salivary cortisol concentrations were lower in children with OSAS, compared to healthy controls. Given that a reduced HPA AA is observed among individuals with chronic stress, it is conceivable that children with OSAS are experiencing chronic psychophysiological stress.

Compared to Controls, Individuals with Lichen Planopilaris Have More Depression, a Lower Self-Esteem, and a Lower Quality of Life

BACKGROUND

Individuals with lichen planopilaris (LPP) typically present with hair loss and an irritated scalp, with signs and symptoms such as itching, erythema, scaling, and burning. Both hair loss and reddened skin may be visible also for other people. Therefore, it is conceivable that individuals with LPP might report a lower mental health status. Accordingly, in the present study, we compared dimensions of mental health between individuals with LPP and healthy controls.

METHOD

A total of 38 individuals with LPP (mean age: 38.24 years, 47.4% females) and 58 gender- and age-matched controls took part in this study. They completed questionnaires covering dimensions of quality of life and self-esteem; experts rated participants' symptoms of depression and anxiety. Furthermore, dermatologists reported on the illness duration, the LPP activity index, and the severity of alopecia.

RESULTS

Compared to healthy controls, individuals with LPP reported lower scores of self-esteem, physical functioning, and mental health and higher scores of role limitations (physical and emotional). Likewise, experts rated higher depression scores in individuals with LPP compared to controls. In individuals with LPP, a higher LPP disease activity and a higher severity of hair loss were associated with higher depression and lower quality-of-life scores. Further, a higher LPP activity index, a lower self-esteem, and higher anxiety scores predicted a poorer quality of life, while illness duration was statistically unrelated.

CONCLUSIONS

Compared to controls, and irrespectively of the illness duration, individuals with LPP reported a lower quality of life and a lower self-esteem, and experts' ratings observed higher scores of depression. Experts treating individuals with LPP might pay special attention to the individuals' mental health status.

Does rTMS on brain areas of mirror neurons lead to higher improvements on symptom severity and empathy compared to the rTMS standard procedure? - Results from a double-blind interventional study in individuals with major depressive disorders

BACKGROUND

A key feature of major depressive disorders is the lack of emotional processing such as empathy. To counter this, we tested, if brain stimulation on areas rich of mirror neurons on the left inferior parietal lobe (lIPL) might improve emotional processing, including empathy, compared to a standard brain stimulation on the left dorsolateral prefrontal cortex (lDLPFC).

METHODS

Twenty inpatients (mean age: 38.9 years; 55% females) with severe major depressive disorders and stable treatment of sertraline at therapeutic dosages were randomly assigned to either the rTMS condition on areas of mirror neuron stimulation, that is, the left inferior parietal lobe (rTMS-lIPL), or to the left dorsolateral prefrontal cortex (rTMS-lDLPFC; control condition). Interventions lasted for two consecutive weeks (2 × 5 interventions of 30'). At baseline and at the end of the study, patients completed questionnaires on current mood state and emotion regulation. In parallel, experts rated patients' depression severity.

RESULTS

Mood improved over time, but more so in the control condition, compared to the rTMS-lIPL condition (medium-large effect sizes). Emotion regulation improved over time; specifically, empathy improved, but only in the rTMS-lIPL condition, compared to the control condition. Symptoms of depression decreased over time, but more so in the rTMS- lIPL condition.

CONCLUSIONS

The pattern of results suggests that among inpatients with severe major depressive disorders, and compared to a standard procedure of rTMS, rTMS targeting on areas rich of mirror neurons appeared to improve emotion regulation, and specifically empathy, while there was no advantage on acute mood.

The selective orexin-2 antagonist seltorexant (JNJ-42847922/MIN-202) shows antidepressant and sleep-promoting effects in patients with major depressive disorder

Excessive arousal has a role in the pathophysiology of major depressive disorder (MDD). Seltorexant (JNJ-42847922/MIN-202) is a selective antagonist of the human orexin-2 receptor (OX2R) that may normalize excessive arousal and thereby attenuate depressive symptoms. In this study, the effects of night-time arousal suppression on depressive symptoms were investigated. 47 MDD patients with a total Inventory of Depressive Symptomatology (IDS) score of ≥30 at screening were included in a randomized, double-blind, diphenhydramine-, and placebo-controlled multicentre study. Symptoms of depression were rated using the 17-item Hamilton Depression Rating Scale (HDRS₁₇). Effects on sleep were evaluated by polysomnography and by the Leeds Sleep Evaluation Questionnaire (LSEQ). To investigate the safety and tolerability of seltorexant, vital signs, suicidal ideation and adverse events were monitored. At baseline the severity of depressive symptoms correlated with sleep efficiency (SE), wake after sleep onset (WASO), duration of stage 2 sleep, and ruminations. Ten days of treatment with seltorexant (and not diphenhydramine) resulted in a significant improvement of core depressive symptoms compared to placebo; the antidepressant efficacy of seltorexant was maintained with continued treatment up to 28 days. Compared to placebo, the antidepressant efficacy of seltorexant coincided with an overall increase in (left posterior) EEG power and a relative increase in delta- and decrease in theta-, alpha- and beta power during stage 2 sleep. Treatment with seltorexant was associated with mild, self-limiting adverse drug reactions. Seltorexant affected core symptoms of depression in the absence of overt changes in the hypnogram; in contrast, diphenhydramine was not efficacious.

Depression and Sleep

Impaired sleep is both a risk factor and a symptom of depression. Objective sleep is assessed using the sleep electroencephalogram (EEG). Characteristic sleep-EEG changes in patients with depression include disinhibition of rapid eye movement (REM) sleep, changes of sleep continuity, and impaired non-REM sleep. Most antidepressants suppress REM sleep both in healthy volunteers and depressed patients. Various sleep-EEG variables may be suitable as biomarkers for diagnosis, prognosis, and prediction of therapy response in depression. In family studies of depression, enhanced REM density, a measure for frequency of rapid eye movements, is characteristic for an endophenotype. Cordance is an EEG measure distinctly correlated with regional brain perfusion. Prefrontal theta cordance, derived from REM sleep, appears to be a biomarker of antidepressant treatment response. Some predictive sleep-EEG markers of depression appear to be related to hypothalamo-pituitary-adrenocortical system activity.

Effects of Aerobic Exercise as Add-On Treatment for Inpatients With Moderate to Severe Depression on Depression Severity, Sleep, Cognition, Psychological Well-Being, and Biomarkers: Study Protocol, Description of Study Population, and Manipulation Check

Background: Aerobic exercise (AE) may be a non-pharmacological strategy to improve depression treatment and lessen the burden of somatic comorbidity of depression. Only few studies have examined the effect of AE as an add-on treatment for moderate to severe depression in an inpatient setting, and most studies have focused on depression severity and cardiovascular parameters. The purpose of the present article is to present the study protocol, to provide information about the assessed study population, and to perform a manipulation check in order to examine whether the intervention program was properly implemented. Methods: We conducted a randomized controlled trial in two centers comparing 6 weeks of AE to a placebo control intervention (stretching) as an add-on to standardized inpatient treatment of moderate to severe depression. Besides depression severity, several other psychological and biological variables were measured such as salivary cortisol, brain-derived neurotropic factor, cognitive tests, and polysomnography. To evaluate long-term effects of the intervention, we also scheduled a follow-up 6 months after completion of the study intervention. Results: Forty-five patients were randomized to either AE (n = 23) or the placebo intervention (n = 22); 36 patients completed the 6-week intervention. In the AE group, 65% completed all 18 training sessions. Patients who were less physically active prior to admission were less likely to complete the study. With regard to energy expenditure, mean kcal/kg/week was 16.4 kcal/kg/week (range: 13.8-17.7), coming close to the targeted dose of 17.5 kcal/kg/week. Conclusions: Overall, patients showed good adherence to the intervention protocol despite at least moderate depression severity. However, the dropout rate suggests that depressed inpatients may need special support to adhere to a structured exercise intervention program. This study will add evidence on the effects of AE as an add-on to inpatient treatment of moderate to severe depression. Besides antidepressant effects, potentially beneficial effects of AE on a broad array of further variables associated with depression will be evaluated. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT02679053.

Heart rate variability and cordance in rapid eye movement sleep as biomarkers of depression and treatment response

OBJECTIVES

The relevance of rapid eye movement (REM) sleep in affective disorders originates from its well-known abnormalities in depressed patients, who display disinhibition of REM sleep reflected by increased frequency of rapid eye movements (REM density). In this study we examined whether heart rate variability (HRV) and prefrontal theta cordance, both derived from REM sleep, could represent biomarkers of antidepressant treatment response.

METHODS

In an open-label, case-control design, thirty-three in-patients (21 females) with a depressive episode were treated with various antidepressants for four weeks. Response to treatment was defined as a ≥50% reduction of HAM-D score at the end of the fourth week. Sleep EEG was recorded after the first and the fourth week of medication. HRV was derived from 3-min artifact-free electrocardiogram segments during REM sleep. Cordance was computed for prefrontal EEG channels in the theta frequency band during tonic REM sleep.

RESULTS

HRV during REM sleep was decreased in depressed patients at week four as compared to controls (high effect size; Cohen's d > 1), and showed a negative correlation with REM density in both, healthy subjects and patients at week four. Further, the fourteen responders had significantly higher prefrontal theta cordance as compared to the nineteen non-responders after the first week of antidepressant medication; in contrast, HRV at week one did not discriminate between responders and non-responders.

CONCLUSIONS

Our data suggest that HRV in REM sleep categorizes healthy subjects and depressed patients, whereas REM sleep-derived prefrontal cordance may predict the response to antidepressant treatment in depressed patients.

Sleep Quality, Sleep EEG Pattern, Mental Well-Being and Cortisol Secretion in Patients with Ruptured Aneurysm Post-Treatment: A Comparison with Post-Surgery Meningioma Patients and Controls

BACKGROUND

Although the chance of surviving an aneurysmal subarachnoid haemorrhage (aSAH) has increased steadily, disturbed sleep and persistent psychological complaints are frequently experienced post-ictus. To date, however, few studies have sought to determine whether physiological parameters, such as objectively measured sleep and cortisol secretion, interrelate significantly with low sleep quality and psychological complaints such as depression. Furthermore, there is little evidence as to whether post-ictal complaints differ between aSAH patients and other groups who have experienced stressful medical intervention.

METHODS

Data on objective and subjective sleep, sleep-related dysfunctional cognitions, psychological functioning and cortisol secretion were collected from 15 patients who had undergone medical intervention for aSAH. Data were also collected from a group of 16 individuals who had undergone surgery for a meningioma and a third group made up of 17 healthy participants.

RESULTS

aSAH patients and meningioma patients had significantly poorer subjective sleep than healthy controls and reported more sleep-related dysfunctional cognitions and hypochondriacal beliefs. They also had a significantly higher morning cortisol response. Finally, a non-significant trend was found showing that aSAH patients and meningioma patients reported poorer psychological functioning than healthy controls.

CONCLUSION

Following treatment, aSAH patients and meningioma patients experience poorer subjective sleep and some differences in objectively measured sleep, which might be attributable to increased sleep-related dysfunctional cognitions and poorer overall psychological functioning. Differences in cortisol production were also observed, suggesting that some physiological imbalances are still present post-ictus.

Personalized Medicine: Review and Perspectives of Promising Baseline EEG Biomarkers in Major Depressive Disorder and Attention Deficit Hyperactivity Disorder

Personalized medicine in psychiatry is in need of biomarkers that resemble central nervous system function at the level of neuronal activity. Electroencephalography (EEG) during sleep or resting-state conditions and event-related potentials (ERPs) have not only been used to discriminate patients from healthy subjects, but also for the prediction of treatment outcome in various psychiatric diseases, yielding information about tailored therapy approaches for an individual. This review focuses on baseline EEG markers for two psychiatric conditions, namely major depressive disorder and attention deficit hyperactivity disorder. It covers potential biomarkers from EEG sleep research and vigilance regulation, paroxysmal EEG patterns and epileptiform discharges, quantitative EEG features within the EEG main frequency bands, connectivity markers and ERP components that might help to identify favourable treatment outcome. Further, the various markers are discussed in the context of their potential clinical value and as research domain criteria, before giving an outline for future studies that are needed to pave the way to an electrophysiological biomarker-based personalized medicine.

Effect of adjuvant sleep hygiene psychoeducation and lorazepam on depression and sleep quality in patients with major depressive disorders: results from a randomized three-arm intervention

BACKGROUND

Sleep disturbances are a common co-occurring disturbance in patients with major depressive disorders (MDDs) and accordingly deserve particular attention. Using a randomized design, we investigated the effects of three different adjuvant interventions on sleep and depression among patients with MDD: a sleep hygiene program (SHP), lorazepam (LOR), and their combination (SHP-LOR).

METHODS

A total of 120 outpatients with diagnosed MDD (mean age: 48.25 years; 56.7% females) and treated with a standard SSRI (citalopram at 20-40 mg at therapeutic level) were randomly assigned to one of the following three conditions: SHP (n=40), LOR (1 mg/d; n=40), SHP-LOR (1 mg/d; n=40). At the beginning and at the end of the study 8 weeks later, patients completed two questionnaires, the Pittsburgh Sleep Quality Index to assess sleep and the Beck Depression Inventory to assess symptoms of depression.

RESULTS

Sleep disturbances decreased over time and in all groups. No group differences or interactions were observed. Symptoms of depression decreased over time and in all three groups. Reduction in symptoms of depression was greatest in the SHP-LOR group and lowest in the LOR group.

CONCLUSION

The pattern of results suggests that all three adjuvant treatments improved symptoms of sleep disturbances and depression, with greater benefits for the SHP-LOR for symptoms of depression, but not for sleep. Nevertheless, risks and benefits of benzodiazepine prescriptions should be taken into account.

Associations between infants' crying, sleep and cortisol secretion and mother's sleep and well-being

BACKGROUND

Infants' continuous crying is a challenge both for the child and the principal caregiver. However, the links between infants' sleep, crying and cortisol secretion and mothers' well-being and sleep have been scarcely investigated. The aim of the present study was therefore to examine the link between cortisol secretion, crying and sleep of infants characterized by infantile colic (IC) and mothers' psychological well-being and own sleep.

METHODS

Mothers of 24 infants characterized by IC (mean age = 8 weeks, SD = 1.5 weeks) completed a series of questionnaires regarding the infant's crying and sleeping patterns. Infants' sleep was objectively assessed with actigraphs. Cortisol secretion was measured by means of saliva samples in the mornings after waking. After 4 weeks, infants were assessed once again. Mothers completed questionnaires assessing their psychological well-being (depressive symptoms, family strain) and sleep.

RESULTS

Mothers' psychological well-being and sleep was greatly predicted by infants' morning saliva cortisol levels, sleep disruptions and crying intensity, whereas infants' crying duration and volume had low predictive value.

CONCLUSIONS

Mothers with infants characterized by IC are at increased risk for reporting impaired sleep, developing depressive symptoms and reporting higher family strain. Most importantly, this risk seems to be greater if their infants' sleep is fragmented.

Chronically restricted or disrupted sleep as a causal factor in the development of depression

Sleep problems are a common complaint in the majority of people suffering from depression. While sleep complaints were traditionally seen as a symptom of mood disorders, accumulating evidence suggests that in many cases the relationship may be reverse as well. A long list of longitudinal studies shows that sleep complaints often precede the onset of depression and constitute an independent risk factor for the development of the disorder. Additionally, experimental studies in animals show that chronically restricted or disrupted sleep may gradually induce neurobiological changes that are very similar to what has been reported for depressed patients. The mechanisms through which insufficient sleep increases the risk for depression are poorly understood but may include effects of sleep disturbance on neuroendocrine stress systems, serotonergic neurotransmission, and various interacting signaling pathways involved in the regulation of neuronal plasticity and neurogenesis. Because sleep is considered to play a crucial role in regulating neuronal plasticity and synaptic strength, chronically insufficient sleep may contribute to depression through an impairment of these plasticity processes leading to altered connectivity and communication within and between brain regions involved in the regulation of mood.

Bullying and parasomnias: a longitudinal cohort study

BACKGROUND AND OBJECTIVES

Environmental factors such as serious trauma or abuse and related stress can lead to nightmares or night terrors. Being bullied can be very distressing for children, and victims display long-term social, psychological, and health consequences. Unknown is whether being bullied by peers may increase the risk for experiencing parasomnias such as nightmares, night terrors, or sleepwalking.

METHODS

A total of 6796 children of the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort were interviewed at elementary school age (8 and 10 years) about bullying experiences with a previously validated bullying interview and at secondary school age (12.9 years) about parasomnias such as nightmares, night terrors and sleepwalking by trained postgraduate psychologists.

RESULTS

Even after adjusting for pre-existing factors related to bullying and parasomnias, being bullied predicted having nightmares (8 years odds ratio [OR], 1.23; 95% confidence interval [CI], 1.05-1.44; 10 years OR, 1.62; 95% CI, 1.35-1.94) or night terrors (8 years OR, 1.39; 95% CI, 1.10-1.75; 10 years OR, 1.53; 95% CI, 1.18-1.98) at age 12 to 13 years. Especially being a chronic victim was associated with both nightmares (OR, 1.82; 95% CI, 1.46-2.27) and night terrors (OR, 2.01; 95% CI, 1.48-2.74). Being a bully/victim also increased the risk for any parasomnia at ages 8 or 10 years (8 years OR, 1.42; 95% CI, 1.08-1.88; 10 years OR, 1.75; 95% CI, 1.30-2.36). In contrast, bullies had no increased risk for any parasomnias.

CONCLUSIONS

Being bullied increases the risk for having parasomnias. Hence, parents, teachers, school counselors, and clinicians may consider asking about bullying experiences if a child is having parasomnias.

Effects of escitalopram/quetiapine combination therapy versus escitalopram monotherapy on hypothalamic-pituitary-adrenal-axis activity in relation to antidepressant effectiveness

The hypothalamic-pituitary-adrenocortical (HPA) system is believed to play an important role in the pathophysiology of major depressive disorder. In this context, the atypical antipsychotic quetiapine (QUE) has been shown to inhibit HPA system activity in healthy subjects. In this study we investigated whether the putative inhibitory effects of QUE on HPA system activity may contribute to its antidepressant efficacy. We analyzed the effects of QUE as an augmentation to the selective serotonin reuptake inhibitor (SSRI) escitalopram (ESC) on HPA system activity in comparison to a monotherapy with ESC in relation to the antidepressant effectiveness. HPA axis activity (cortisol and ACTH) was measured by means of the dexamethasone/corticotropin-releasing hormone (DEX/CRH) test which was performed before (week 0) and during (week 1, week 5) antidepressant psychopharmacotherapy. The combination therapy, but not the ESC monotherapy showed significantly inhibiting effects on HPA system activity leading to stepwise down-regulation. ACTH concentrations were reduced in the ESC/QUE group during five weeks of treatment. The inhibitory effect of QUE maybe involved in its antidepressant effects as an augmentation strategy.

Guidelines for the recording and evaluation of pharmaco-sleep studies in man: the International Pharmaco-EEG Society (IPEG)

The International Pharmaco-EEG Society (IPEG) presents guidelines summarising the requirements for the recording and computerised evaluation of pharmaco-sleep data in man. Over the past years, technical and data-processing methods have advanced steadily, thus enhancing data quality and expanding the palette of sleep assessment tools that can be used to investigate the activity of drugs on the central nervous system (CNS), determine the time course of effects and pharmacodynamic properties of novel therapeutics, hence enabling the study of the pharmacokinetic/pharmacodynamic relationship, and evaluate the CNS penetration or toxicity of compounds. However, despite the presence of robust guidelines on the scoring of polysomnography -recordings, a review of the literature reveals inconsistent -aspects in the operating procedures from one study to another. While this fact does not invalidate results, the lack of standardisation constitutes a regrettable shortcoming, especially in the context of drug development programmes. The present guidelines are intended to assist investigators, who are using pharmaco-sleep measures in clinical research, in an effort to provide clear and concise recommendations and thereby to standardise methodology and facilitate comparability of data across laboratories.

Cortisol levels and sleep patterns in infants with orofacial clefts undergoing surgery

BACKGROUND

Traumatic events during early infancy might damage infants' psychobiological functioning, such as sleep and cortisol secretion. Infants born with orofacial clefts (OFCs) undergo functional, anatomical, and aesthetic surgery. The aim of the present study was to determine whether infants with OFC and undergoing OFC surgery show deteriorated sleep and cortisol secretion compared with healthy controls and with their presurgery status.

METHODS

A total of 27 infants with OFC (mean age: 22 weeks) and 30 healthy controls (mean age: 23 weeks) took part in the study. For infants with OFC, sleep actigraphy was performed and saliva cortisol was analyzed 5 days before, during, and 5 days after surgery. For controls, sleep and saliva cortisol were assessed similarly, except for the period taken up with surgery.

RESULTS

Compared with healthy controls, infants with OFC undergoing OFC surgery did not differ in sleep and cortisol secretion. Their sleep and cortisol secretion did deteriorate during the perisurgical period but recovered 5 days postsurgery.

CONCLUSION

In infants with OFC undergoing corrective surgery, the pattern of results for sleep and cortisol suggests that OFC surgery does not seem to constitute a traumatic event with long-term consequences.

EEG biomarkers in major depressive disorder: discriminative power and prediction of treatment response

Major depressive disorder (MDD) has high population prevalence and is associated with substantial impact on quality of life, not least due to an unsatisfactory time span of sometimes several weeks from initiation of treatment to clinical response. Therefore extensive research focused on the identification of cost-effective and widely available electroencephalogram (EEG)-based biomarkers that not only allow distinguishing between patients and healthy controls but also have predictive value for treatment response for a variety of treatments. In this comprehensive overview on EEG research on MDD, biomarkers that are either assessed at baseline or during the early course of treatment and are helpful in discriminating patients from healthy controls and assist in predicting treatment outcome are reviewed, covering recent decades up to now. Reviewed markers include quantitative EEG (QEEG) measures, connectivity measures, EEG vigilance-based measures, sleep-EEG-related measures and event-related potentials (ERPs). Further, the value and limitations of these different markers are discussed. Finally, the need for integrated models of brain function and the necessity for standardized procedures in EEG biomarker research are highlighted to enhance future research in this field.

Influence of mindfulness practice on cortisol and sleep in long-term and short-term meditators

BACKGROUND

There is growing scientific interest in assessing the biological correlates of non-pharmacological interventions such as mindfulness. Examinations of the beneficial effects of mindfulness on hypothalamus-pituitary-adrenocortical system activity (HPA SA) and sleep are sparse. The aim of the present study was to explore the impact of long- and short-term meditation experience on HPA SA and sleep.

METHOD

There were 20 participants, 9 of whom had long-term experience in meditation (mean = 264 months) and 11 novices. Novices underwent an 8-week course in Mindfulness-Based Stress Reduction (MBSR), and cortisol samples were taken in the lab at the beginning and end of the course. To assess the cortisol awakening response, 4 morning cortisol samples were collected. Sleep and mindfulness were assessed by self-rating questionnaires.

RESULTS

Among participants with long-term meditation experience, morning cortisol decreased with length of experience. For novices, after an 8-week introductory MBSR course, morning cortisol levels had decreased, while both sleep and self-attribution of mindfulness significantly improved. Cortisol levels did not, however, change between the beginning and end of individual MBSR sessions.

CONCLUSIONS

The pattern of results lends support to the view that MBSR/meditation has a favorable influence both on biomarkers of stress regulation, such as cortisol secretion, and on sleep.

Visually detected NREM Stage 2 sleep spindles in kindergarten children are associated with stress challenge and coping strategies

OBJECTIVES

Sleep EEG spindles are linked to efficient cortical-subcortical connectivity and intellectual abilities. The aim of the present study was to investigate the relationship of spindle activity to psychosocial stress response and coping strategies in healthy kindergarten children.

METHODS

In a cross-sectional study of 41 5-year old kindergarten children we examined stress-induced hypothalamic-pituitary-adrenocortical (HPA) system activity by saliva cortisol measurements and sleep regulation by sleep EEG-monitoring. Stress response was measured during the application of a standardized psychological challenge appropriate at this age. NREM S2 sleep EEG spindles were visually scored and put into relation to coping and HPA activity parameters.

RESULTS

An increased total number of NREM S2 sleep spindles correlated positively with increased high ego-involvement strategies such as "positive emotions". By contrast, total number of NREM S2 sleep spindles correlated negatively with low ego-involvement strategies such as "denial" and "avoidance". Stress induced HPA-activity correlated positively with coping strategies with high ego-involvement; while there was no correlation with low ego-involvement strategies.

CONCLUSIONS

Total number of visually detected NREM S2 sleep spindles is elevated in children with coping involving positive, high ego-involvement; in contrast, low ego-involvement during stress is associated with reduced total number of NREM S2 sleep spindles.

Altered slow wave activity in major depressive disorder with hypersomnia: a high density EEG pilot study

Hypersomnolence in major depressive disorder (MDD) plays an important role in the natural history of the disorder, but the basis of hypersomnia in MDD is poorly understood. Slow wave activity (SWA) has been associated with sleep homeostasis, as well as sleep restoration and maintenance, and may be altered in MDD. Therefore, we conducted a post-hoc study that utilized high density electroencephalography (hdEEG) to test the hypothesis that MDD subjects with hypersomnia (HYS+) would have decreased SWA relative to age- and sex-matched MDD subjects without hypersomnia (HYS-) and healthy controls (n=7 for each group). After correction for multiple comparisons using statistical non-parametric mapping, HYS+ subjects demonstrated significantly reduced parieto-occipital all-night SWA relative to HYS- subjects. Our results suggest hypersomnolence may be associated with topographic reductions in SWA in MDD. Further research using an adequately powered prospective design is indicated to confirm these findings.

Clinical relevance of disturbances of sleep and vigilance in major depressive disorder: a review

OBJECTIVE

The primary objective of this article is to provide a concise review of the clinical relevance of sleep and vigilance in major depressive disorder.

DATA SOURCES

PubMed was reviewed (1990-2009) and English-language articles were identified using the key words sleep and depression and sleep and antidepressants. Secondary searches included articles cited in sources identified by the primary search.

STUDY SELECTION

The narrative review provides brief descriptions of the normal physiology of sleep and changes associated with depression, as well as the impact of various treatments on these processes.

DATA SYNTHESIS

Although it has long been known that sleep disturbances are an important characteristic of depression, relatively few studies have been conducted with the newer-generation antidepressants. Neither of the most widely used classes of antidepressants, the selective serotonin reuptake inhibitors and the serotonin-norepinephrine reuptake inhibitors, have particularly beneficial effects on sleep and, among the medications that reliably improve sleep efficiency, including mirtazapine and the tricyclic antidepressants, problems with daytime sedation can offset therapeutic benefit. Despite relatively widespread use, trazodone has not been demonstrated to be an effective and safe hypnotic in patients taking other antidepressants. For many patients, ongoing concomitant treatment with benzodiazepines and related drugs is the preferred option, again without convincing empirical support of longer-term efficacy. Among newer and investigational antidepressants, agomelatine shows promise with respect to both overall safety and effects on insomnia, although possible negative effects on liver function warrant further study.

CONCLUSIONS

Sleep disturbances are a significant aspect of depressive syndromes, and relief of insomnia remains an important unmet need in antidepressant therapeutics. Development of a well-tolerated antidepressant medication that rapidly improves sleep maintenance without daytime sedation is a priority for drug development.

'Oh, baby, please don't cry!': in infants suffering from infantile colic hypothalamic-pituitary-adrenocortical axis activity is related to poor sleep and increased crying intensity

BACKGROUND/AIM

Infantile colic (IC) is considered to represent the upper end of the spectrum of early developmental crying behavior. Little is known about hypothalamic-pituitary-adrenocortical axis activity and sleep in relation to infants' crying. The aim of the present study was to assess cortisol secretion in infants in relation to their sleep and crying patterns.

METHOD

Sixteen infants (mean age: 8 weeks; SD = 1.5 weeks) were enrolled. Their mothers completed a series of questionnaires regarding the infants' crying and sleeping patterns. The infants' sleep was objectively assessed with actigraphs. After 4 weeks, the infants were assessed once again. Cortisol secretion was measured by means of saliva samples in the mornings after awakening.

RESULTS

Morning saliva cortisol levels were related to more frequent awakening and to increased crying intensity, but not to sleep or crying duration. Over 4 weeks, both crying behavior and sleep duration decreased, but there was no association between them. Cortisol secretion did not significantly change.

CONCLUSIONS

In infants suffering from IC, fragmented sleep patterns and increased saliva cortisol levels were related. Cortisol secretion seems to be related to crying intensity, but not to crying duration. Crying intensity may reflect greater physiological or psychological stress rather than mere duration of crying.

In healthy young and elderly adults, hypothalamic-pituitary-adrenocortical axis reactivity (HPA AR) varies with increasing pharmacological challenge and with age, but not with gender

BACKGROUND

Hypothalamic-pituitary-adrenocortical axis reactivity (HPA AR) is the key indicator of the psychophysiological response to stress. The HPA AR may vary with age and gender. To investigate these factors concurrently, the aims of the present study were to observe HPA AR (plasma ACTH and plasma cortisol) in response to a pharmacological challenge (dexamethasone/corticotropin releasing hormone test: DEX/CRH-test) and as a function of age and gender.

METHOD

19 young (10 females and 9 males; mean age = 24.05 years) and 23 elderly (11 females and 12 males; mean age = 71.61 years) healthy volunteers took part in the study. To assess HPA AR, participants underwent the combined DEX/CRH test applied with the following DEX doses: 0.75, 1.5, and 3.0 mg, respectively.

RESULTS

A dose-dependent response was observed in young adult participants, but not in elderly participants. With increasing DEX doses, ACTH and cortisol values decreased in young adult participants, while the decrease was blunted among elderly compared to young adult participants. No differences were observed for gender.

CONCLUSIONS

Results point to diminished HPA axis sensitivity as an effect of normal aging, irrespective of gender. Therefore, altered HPA regulation in old age should be taken into account for developing new therapeutic approaches acting on the HPA axis and its receptor mechanisms.

Intensive two-day cognitive-behavioral intervention decreases cortisol secretion in soldiers suffering from specific phobia to wear protective mask

RESEARCH QUESTIONS

Wearing a protective mask is compulsory for those in professions such as fire-fighters, rescue personnel and soldiers. The phobia to wear a protective mask is considered a specific claustrophobia and may become of major concern during military service. To date, no data are available with respect to the hypothalamus-pituitary-adrenocortical system activity (HPA SA) for both the so-called protective mask phobia (PMP) and its treatment. The aim of the present study was three-fold: 1) to assess HPA SA in soldiers suffering from PMP before and after intensive cognitive-behavioral treatment, 2) to compare these data with controls, and 3) to relate these data to subjective sleep.

METHODS

46 Swiss Army recruits suffering from PMP were enrolled in a two-day intensive treatment course. During initial and final assessments, saliva was sampled to analyse HPA SA via salivary cortisol; saliva samples were also gathered in the morning. For comparison, saliva samples were gathered of 39 Emergency Rescue Service (ERS) recruits. All participants also completed a questionnaire related to sleep and to anxiety.

RESULTS

Compared to controls from the ERS, among army recruits suffering from PMP, cortisol secretion was significantly higher during initial and final assessments, and in the morning. Cortisol secretion decreased from initial and final assessment. Subjectively assessed sleep was more impaired in recruits suffering from PMP compared to controls. After cognitive-behavioral treatment, all recruits suffering from PMP were able to wear the protective mask.

CONCLUSIONS

Specific phobia about wearing a protective mask is treatable via a two-day intensive course. Treatment success is reflected in modified HPA SA. Methodology and results may be transferred to treat patients suffering from sleep apnea syndrome and presenting high anxiety about wearing continuous positive airway pressure devices.

The stress hormone system in various sleep disorders

Hypothalamic-pituitary-adrenal (HPA)-system activity is regulated by the suprachiasmatic nucleus, the primary endogenous circadian pacemaker. In addition, sleep plays an important modulatory role. However, data on HPA-system activity in sleep disorders are quite conflicting. A sensitive challenge test to assess negative feedback sensitivity of the HPA-system like the dexamethasone/corticotropin-releasing-hormone (DEX/CRH)-test has never been used so far in sleep disorders. Therefore we studied 25 obstructive sleep apnea (OSA) patients, 18 restless legs syndrome (RLS) patients, 21 patients with primary insomnia and compared them to 33 healthy controls. The dynamic response of the HPA-system was assessed by the DEX/CRH-test which combines suppression (dexamethasone) and stimulation (CRH) of the stress hormone system. After HPA-axis suppression the number of non-suppressors did not differ among groups indicating normal negative feedback sensitivity. In RLS patients ACTH levels were slightly lower compared to controls while cortisol levels were similar between groups. Following CRH stimulation we did not detect differences in ACTH- or cortisol levels and adrenocortical responsitivity to ACTH was comparable between groups. These results for the first time document normal HPA-system feedback sensitivity in various sleep disorders and suggest that abnormalities of the stress hormone system in affective disorders are unlikely due to concomitant sleep problems.

Poor sleep is associated with exaggerated cortisol response to the combined dexamethasone/CRH test in a non-clinical population

Although sleep disturbance has been shown to be associated with psychological distress and the hypothalamic-pituitary-adrenal (HPA) axis function, the simultaneous relationship between sleep, distress and HPA axis function is less clear. Here we examined the relationship between sleep quality as assessed with the Pittsburgh Sleep Quality Index, psychological distress as assessed with the Hopkins Symptom Checklist, and cortisol responses to the dexamethasone (DEX)/corticotropin-releasing hormone (CRH) test in 139 non-clinical volunteers. Poor sleep was significantly correlated with greater cortisol response to the combined DEX/CRH challenge, but not with the cortisol level just before CRH challenge. When subjects were divided into three groups based on the suppression pattern of cortisol (i.e., incomplete-, moderate-, and enhanced-suppressors), poor sleep was significantly associated with the incomplete suppression in women while no significant association was found between sleep and the enhanced suppression. The association between poor sleep and exaggerated cortisol response to the CRH challenge became more clear in the regression analysis where the confounding effect of psychological distress was taken into consideration. These results indicate that poor sleep would be associated with exaggerated cortisol reactivity. The observed association of poor sleep with reactive cortisol indices to the CRH challenge, but not with the cortisol level after DEX administration alone, might add to the well-established evidence demonstrating the role of CRH in the regulation of sleep. Our findings further suggest that the mediation model would work better than the bivariate approach in investigating the relationship between sleep, distress and HPA axis reactivity.

Sleep and its importance in adolescence and in common adolescent somatic and psychiatric conditions

Restoring sleep is strongly associated with a better physical, cognitive, and psychological well-being. By contrast, poor or disordered sleep is related to impairment of cognitive and psychological functioning and worsened physical health. These associations are well documented not only in adults but also in children and adolescents. Importantly, adolescence is hallmarked by dramatic maturational changes in sleep and its neurobiological regulation, hormonal status, and many psychosocial and physical processes. Thus, the role of sleep in mental and physical health during adolescence and in adolescent patients is complex. However, it has so far received little attention. This review first presents contemporary views about the complex neurobiology of sleep and its functions with important implications for adolescence. Second, existing complex relationships between common adolescent somatic/organic, sleep-related, and psychiatric disorders and certain sleep alterations are discussed. It is concluded that poor or altered sleep in adolescent patients may trigger and maintain many psychiatric and physical disorders or combinations of these conditions, which presumably hinder recovery and may cross into later stages of life. Therefore, timely diagnosis and management of sleep problems appear critical for growth and development in adolescent patients.

Children suffering from separation anxiety disorder (SAD) show increased HPA axis activity compared to healthy controls

RESEARCH QUESTIONS

Separation anxiety disorder (SAD) is one of the most common mental disorders in childhood, and one of the earliest emerging. Little is known about the association between SAD and the hypothalamic-pituitary-adrenocortical (HPA) axis activity. Therefore, the present study aimed at investigating this association in children suffering from separation anxiety compared to healthy controls.

METHODS

A total of 31 children with diagnosed SAD (mean age: 8.45; 17 females, 14 males) and 25 healthy controls (HC; mean age: 9.74; 12 females, 13 males) took part in the study. All participants underwent psycho-physiological testing for HPA axis challenge. Testing consisted of a separation and a social exposure paradigm. Saliva samples to assess HPA axis-related cortisol secretion were gathered in parallel.

RESULTS

Compared to healthy controls, children with SAD showed greatly increased HPA axis activity, as reflected by an increased cortisol secretion throughout the entire period of investigation. The rise of cortisol was already observed in anticipation of, but not following the separation paradigm. No gender-related differences of cortisol secretion were observed.

CONCLUSIONS

Separation anxiety disorder (SAD) in children is reflected in greatly increased HPA axis activity. Compared to healthy controls, children with SAD showed increased cortisol values from the beginning of, and throughout, the entire investigation. This pattern of results suggests that both the anticipation of a separation and a persistent hyperactivity of the HPA axis system leads to an increased cortisol secretion.

Neuroticism mediates the relationship between childhood adversity and adult sleep quality

This study investigated the relationship of childhood adversity and adult sleep quality in 327 college students (91 males), with a mean age of 18.9 years (SD = 2.1) and also examined whether neuroticism significantly mediated the observed association. Regression findings indicate that the relationship between childhood adversity and adult sleep quality is significant, and that there is a stronger association in men. Furthermore, a bootstrapping approach to testing the significance of the indirect effect (i.e., mediation) indicated that neuroticism mediated this relationship in both men and women. These data suggest that otherwise healthy young adults with a history of childhood adversity are at increased risk for sleep disturbance. Neuroticism may represent a potential target for change in future insomnia interventions, particularly in adults with a history of childhood adversity.

Modafinil reduces microsleep during partial sleep deprivation in depressed patients

OBJECTIVE

Sleep deprivation (SD) can induce a prompt decrease in depressive symptoms within 24h. Following the recovery night, however, a relapse into depression occurs in most patients. Recovery sleep, naps and even very short episodes of sleep (microsleep; MS) during SD have been shown to provoke a rapid relapse into depression. This study tested the hypothesis that modafinil reduces MS during SD and stabilizes the treatment response to PSD compared to placebo.

METHODS

A total of 28 patients (13 men, 15 women; age 45.1+/-12.1 years) with a major depressive episode and a cumulative daytime microsleep of five or more minutes were investigated using a double-blind placebo-controlled study design. All patients were treated with a stable mirtazapine monotherapy. A partial SD (PSD) was performed after one week. Additional morning treatment with modafinil vs. placebo started during PSD and was maintained over two weeks. Sleep-EEG and MS episodes were recorded with a portable EEG. Depression severity was assessed using the Hamilton Depression Rating Scale before, during and after PSD and at follow-ups after one and two weeks.

RESULTS

Patients treated with modafinil showed significantly reduced microsleep during PSD (11.63+/-15.99 min) compared to the placebo group (47.77+/-65.31 min). This suppression of MS was not associated with the antidepressive effect of PSD.

CONCLUSIONS

Compared to placebo, modafinil was efficient in reducing daytime microsleep following partial sleep deprivation but did not enhance the antidepressive effects of PSD and did not stabilize antidepressive effects over two weeks.

The relation between sleep and pain among a non-clinical sample of young adults

Poor sleep is linked to poorer daily functioning and increased risk of psychiatric symptoms. With respect to pain, the relation is bi-directional; poor sleep exacerbates pain, while greater pain adversely affects sleep. Moreover, perception of pain is subject to cognitive-emotional processes. Surprisingly, no data are available from non-clinical samples of young adults. The aim of the present study was therefore to investigate the relation between sleep and pain as a function of quality of life and depressive symptoms in young adults. The direction of influence between sleep and pain was statistically tested with two different structural equation models (SEMs). A total of 862 participants (639 women, 223 men; mean age: 24.67; SD = 5.91) completed a series of validated self-report questionnaires assessing sleep, quality of life, depressive symptoms and cognitive-emotional elaboration of pain. Sleep, pain, quality of life, and depressive symptoms were interrelated. The first SEM suggested both a direct and an indirect influence of pain on sleep, whereas the second SEM suggested that sleep had only an indirect influence on pain. Irrespective of the SEM, the relation between sleep and cognitive-emotional elaboration of pain was mediated by quality of life and depressive symptoms. For a non-clinical sample of young adults, findings did support the bi-directional relation between poor sleep and increased cognitive-emotional elaboration of pain, though other cognitive-emotional processes such as depressive symptoms and quality of life should be taken into account.

Associations between satisfaction with life, burnout-related emotional and physical exhaustion, and sleep complaints

OBJECTIVES

Burnout is a state of work-related emotional and physical exhaustion. Burnout is related to sleep complaints. By contrast, people with optimistic attitude seem to be less vulnerable to stress and burnout. Therefore, the present study aimed at investigating the relation between burnout, depressive symptoms, satisfaction with life, and sleep complaints.

METHODS

A total of 2231 participants (age [years]: M=40.8; 1183 females and 1048 males) took part in the study. Participants completed a series of questionnaires such as the Tedium Measure, the Insomnia Severity Index, and the Satisfaction with Life-questionnaire. For statistical analyses, a Structural Equation Model (SEM) was applied.

RESULTS

Pessimism, emotional and physical exhaustion, depressive symptoms, and low satisfaction with life were interrelated. Emotional and physical exhaustion was related to sleep complaints, whereas sleep complaints were not related to depressive symptoms and pessimism. Satisfaction with life was related to low sleep complaints, though mediated via low emotional and physical exhaustion, and low pessimism.

CONCLUSIONS

Results suggest that among burnout symptoms emotional and physical exhaustion, but not depressive symptoms, are related to sleep complaints. Satisfaction with life, via low emotional and physical exhaustion, and low pessimism, further contributes to favourable sleep.

Poor reported sleep quality predicts low positive affect in daily life among healthy and mood-disordered persons

Sleep disturbance is a core symptom of mood disorders. However, surprisingly little is known about the relationship between sleep quality and ambulatory daily mood, especially in mood-disordered populations. We assessed ambulatory positive affect (PA) and negative affect (NA) 10 times daily for three consecutive days with the computerized experience sampling method among persons with major depression (n = 35), minor depression (n = 25) and healthy controls (n = 36). Sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI). Poorer sleep quality predicted lower ambulatory PA, even after accounting for the effects of diagnostic group and self-reported anxiety. Conversely, sleep quality did not predict ambulatory NA once diagnostic group was accounted for. Analyzes of specific PSQI component scores indicated that poor subjective sleep quality and self-reported daytime dysfunction were the sleep components most strongly tied to reports of low ambulatory PA. Impaired sleep quality may be responsible for reduced pleasurable experience in everyday life.

Wake and sleep EEG provide biomarkers in depression

Both wake and sleep electroencephalogram (EEG) provide biomarkers of depression and antidepressive therapy, respectively. For a long time it is known that EEG activity is altered by drugs. Quantitative EEG analysis helps to delineate effects of antidepressants on brain activity. Cordance is an EEG measure with a superior correlation with regional brain perfusion. Prefrontal quantitative EEG cordance appears to be a predictor of the response to antidepressants. Sleep EEG shows characteristic changes in depression as impaired sleep continuity, desinhibition of REM sleep and changes of nonREM sleep. Elevated REM density (a measure for frequency of rapid eye movements) characterizes an endophenotype in family studies of depression. REM-sleep changes including a more distinct REM rebound after sleep deprivation are found in animal models of depression. Most antidepressants suppress REM sleep in depressed patients, normal controls and laboratory animals. REM suppression appears to be a distinct, but not an absolute requirement for antidepressive effects of a compound. Sleep-EEG variables like REM latency or certain clusters of variables were shown to predict the response to the treatment with a certain antidepressant or even the course of the disorder for several years. Some of these predictive sleep-EEG markers of the longterm course of depression appear to be closely related to hypothalamo-pituitary-adrenocortical system activity.

Sleep actigraphy pattern and behavioral/emotional difficulties in kindergarten children: association with hypothalamic-pituitary-adrenocortical (HPA) activity

BACKGROUND

Various studies of adult endocrinology and sleep show close connections between poor sleep quality, deterioration of the HPA axis and negative psychological characteristics. However, the extent to which these associations may have already emerged and developed in childhood remains unclear.

METHODS

A total of 82 preschoolers (age 4.91+/-0.48) underwent activity monitoring for seven consecutive days and nights, wearing a digital movement-measuring instrument. Additionally, on the first and on the last morning of sleep registration, the activity of the HPA axis was assessed via the amount of cortisol in the saliva. Psychological and behavioral assessments were also made.

RESULTS

Three sub-groups of good (22%), normal (58.5%) and poor (19.5%) sleepers were distinguished. Poor sleep patterns were associated with higher HPA activity and with behavioral/emotional difficulties.

CONCLUSIONS

The interplay between unfavorable sleep patterns, deterioration of the HPA axis and behavioral/emotional difficulties is already apparent in pre-school children.

Impact of sleep and its disturbances on hypothalamo-pituitary-adrenal axis activity

The daily rhythm of cortisol secretion is relatively stable and primarily under the influence of the circadian clock. Nevertheless, several other factors affect hypothalamo-pituitary-adrenal (HPA) axis activity. Sleep has modest but clearly detectable modulatory effects on HPA axis activity. Sleep onset exerts an inhibitory effect on cortisol secretion while awakenings and sleep offset are accompanied by cortisol stimulation. During waking, an association between cortisol secretory bursts and indices of central arousal has also been detected. Abrupt shifts of the sleep period induce a profound disruption in the daily cortisol rhythm, while sleep deprivation and/or reduced sleep quality seem to result in a modest but functionally important activation of the axis. HPA hyperactivity is clearly associated with metabolic, cognitive and psychiatric disorders and could be involved in the well-documented associations between sleep disturbances and the risk of obesity, diabetes and cognitive dysfunction. Several clinical syndromes, such as insomnia, depression, Cushing's syndrome, sleep disordered breathing (SDB) display HPA hyperactivity, disturbed sleep, psychiatric and metabolic impairments. Further research to delineate the functional links between sleep and HPA axis activity is needed to fully understand the pathophysiology of these syndromes and to develop adequate strategies of prevention and treatment.

Dex/CRH-test response and sleep in depressed patients and healthy controls with and without vulnerability for affective disorders

Sleep electroencephalographic (EEG) abnormalities and increased hypothalamo-pituitary-adrenal (HPA) axis activity are the most prominent neurobiological findings in depression and were suggested as potential biomarker for depression. In particular, increased rapid eye movement sleep (REM) density, deficit in slow wave sleep and excessive stress hormone response are associated with an unfavorable long-term outcome of depression. Recent studies indicate that the sleep and endocrine parameters are related to each other. This study investigated the association of sleep structure including a quantitative EEG analysis with the results of the combined dexamethasone (Dex)/corticotropin-releasing hormone (CRH)-test in 14 patients with a severe major depression, 21 healthy probands with a positive family history of depression (HRPs) and 12 healthy control subjects without personal and family history for psychiatric disorders. As expected patients with depression showed an overactivity of the HPA axis, disturbed sleep continuity and prolonged latency until slow wave sleep in the first sleep cycle. Differences in microarchitecture of sleep were less prominent and restricted to a higher NonREM sigma power in the HRP group. Dexamethasone suppressed cortisol levels were positively associated with higher NonREM sigma power after merging the three groups. We also observed an inverse association between the ACTH response to the Dex/CRH-test and rapid eye movement sleep (REM) density in HRPs, with suggestive evidence also in patients, but not in controls. This contra-intuitive finding might be a result of the subject selection (unaffected HRPs, severely depressed patients) and the complementarity of the two markers. HRPs and patients with high disease vulnerability, indicated by an elevated REM density, seem to have a lower threshold until an actual disease process affecting the HPA axis translates into depression, and vice versa. To summarize, our findings provide further evidence that the HPA axis is involved in the sleep regulation in depression. These associations, however, are not unidimensional, but dependent on the kind of sleep parameters as well as on the selection of the subjects.

The Munich vulnerability study on affective disorders: microstructure of sleep in high-risk subjects

Vulnerability markers for affective disorders have focused on stress hormone regulation and sleep. Among rapid eye movement (REM) sleep, increased REM pressure and elevated REM density are promising candidates for vulnerability markers. Regarding nonREM sleep, a deficit in amount of and latency until slow wave sleep during the first half of the night is a characteristic for depression. To further elucidate whether changes in the microstructure of sleep may serve as vulnerability markers we investigated the premorbid sleep composition in 21 healthy high-risk proband (HRPs) with a positive family history for affective disorders and compared HRPs with a control group of healthy subjects (HCs) without personal and family history for psychiatric disorders. The sleep electroencephalogram (EEG) was conventionally scored and submitted to a quantitative EEG analysis. The main difference in sleep characteristics between HRPs and HCs was an abnormally increased REM density. Differences in the spectral composition of sleep EEG were restricted to an increased power in the sigma frequency range. Since the HRP group comprised six unrelated and 15 related subjects we controlled for sibling effects. We could replicate the increased REM density in the group of HRPs whereas elevated power in the low sigma frequencies persisted only with approaching significance. The present study further supports elevated REM density as putative vulnerability marker for affective disorders. However, sleep EEG in our group of HRPs did not show slow wave sleep abnormalities. Ongoing follow up investigations of HRPs will clarify whether the observed increase in sigma EEG activity during nonREM sleep is of clinical relevance with respect to the likelihood to develop an affective disorder.