Multimodal in-vehicle lighting system increases daytime light exposure and alertness in truck drivers under Arctic winter conditions

Drowsiness while driving negatively impacts road safety, especially in truck drivers. The present study investigated the feasibility and alerting effects of a daylight-supplementing in-truck lighting system (DS) providing short-wavelength enriched light before, during, and after driving. In a within-participants design, eight truck drivers drove a fully-loaded truck under wintry Scandinavian conditions (low daylight levels) with a DS or placebo system for five days. Subjective and objective measures of alertness were recorded several times daily, and evening melatonin levels were recorded three times per study condition. DS significantly increased daytime light exposure without causing negative side effects while driving. In addition, no negative carry-over effects were observed on evening melatonin and sleepiness levels or on nighttime sleep quality. Moreover, objective alertness (i.e., psychomotor vigilance) before and after driving was significantly improved by bright light exposure. This effect was accompanied by improved subjective alertness in the morning. This field study demonstrated that DS was able to increase daytime light exposure in low-daylight conditions and to improve alertness in truck drivers before and after driving (e.g., during driving rest periods). Further studies are warranted to investigate the effects of daylight-supplementing in-cabin lighting on driving performance and road safety measures.

Prospective analyses of alertness, sleep, and fitness to drive one year after de novo multiple sclerosis diagnosis

BACKGROUND

The prevalence and functional burden of the chronic demyelinating disease multiple sclerosis (MS) are well documented; however, little is known about the initial clinical course of alertness, sleep, cognitive, and psychological symptoms.

OBJECTIVES

This exploratory, prospective, longitudinal study multidimensionally investigated the development and progression of alertness, sleep, fitness to drive, and psychological symptoms in the first year after de novo MS diagnosis.

METHODS

Twenty-five people with MS (pwMS) were assessed cognitively, psychologically, and using polysomnography soon after diagnosis and one year later, with outcomes compared to matched healthy controls.

RESULTS

In the early stage of the disease, psychological symptoms of pwMS were comparable with those of controls, and patient conditions did not deteriorate within the first disease year. A small percentage of pwMS experienced increased levels of anxiety and depression after diagnosis. Alertness, sustained attention, and fitness to drive were comparable between both groups, and fatigue levels remained low over the course of the year.

CONCLUSIONS

This study highlights patient experiences within the initial clinical course of MS in a small group of patients. Further research is needed to understand the progression of symptoms and impairments in MS over a longer period and in different stages of the disease.

GABAergic Effects of Etifoxine and Alprazolam Assessed by Double Pulse TMS

INTRODUCTION

There is a need for novel anxiolytics with improved side effect profiles compared to benzodiazepines. A promising candidate with alternative pharmacodynamics is the translocator protein ligand, etifoxine.

METHODS

To get further insight into its mechanisms of action and side effects compared to the benzodiazepine alprazolam, we performed a double-blind, placebo-controlled, repeated-measures study in 36 healthy male subjects. Participants were examined for trait anxiety and side effects and underwent repeated transcranial magnetic stimulation (TMS) assessments, including motor evoked potentials (MEP), short intracortical inhibition (SICI), intracortical facilitation (ICF), and cortical silent period (CSP).

RESULTS

We observed attenuation of MEPs by alprazolam but not by etifoxine. SICI was not significantly affected by alprazolam or etifoxine. However, the response pattern indicated a lowered SICI threshold after the administration of etifoxine and alprazolam compared to the placebo. ICF and CSP were influenced by neither medication. Alprazolam led to higher sedation and subjective impairment of concentration compared to etifoxine. Individual anxiety trait scores did not affect TMS parameters.

DISCUSSION

This study indicated a favorable side effect profile of etifoxine in healthy volunteers. Moreover, it revealed differential GABA-related effects on neuromuscular function by means of TMS. The side effects and TMS profile of etifoxine are compatible with the involvement of neurosteroidogenesis and a predominant α3 subunit modulation compared to alprazolam.

Low Sleep Satisfaction Is Related to High Disease Burden in Tinnitus

Previous studies have shown a high prevalence of sleep disturbances in tinnitus patients. However, no study has yet evaluated subjective sleep satisfaction. The present study aimed to investigate associations of self-reported sleep satisfaction with sociodemographic factors, tinnitus-related distress, depression, and self-reported quality of life. This is a retrospective analysis of 2344 outpatients with tinnitus presenting at a tertiary German tinnitus clinic from 2010 to 2020. Patients who filled in five questionnaires (Tinnitus Handicap Inventory (THI), Tinnitus Questionnaire (TQ), Major Depression Inventory (MDI), Tinnitus Sample Case History Questionnaire (TSCHQ), and the World Health Organization Quality of Life Brief Version (WHOQOL-Bref)) were included. Based on the question about sleep satisfaction in the WHOQOL-Bref, group classification into (I) sleep-satisfied, (II) neither satisfied or dissatisfied, and (III) sleep-dissatisfied patients was performed. Associations between sleep satisfaction and quality of life, depression, tinnitus distress, and tinnitus characteristics were analyzed by group differences and a multinomial regression model with elastic net penalization. A total of 42.38% of patients were satisfied or very satisfied with sleep, whereas 40.91% of patients were dissatisfied or very dissatisfied with sleep. The remaining patients reported being neither satisfied nor dissatisfied with sleep. Sleep-dissatisfied patients were significantly more burdened in questionnaires on depressive symptoms (MDI), tinnitus distress (TQ, THI), and quality of life (WHOQOL-Bref). In addition, they suffered significantly more often from comorbidities such as headache, neck pain, or temporomandibular joint disorder (TMJ). The elastic net regression based on sum scores of THI, TQ, MDI, the four domains of WHOQOL-Bref, as well as all individual questions from the TSCHQ was able to classify patients satisfied with their sleep with an accuracy of 79%, 87.8% sensitivity, and 70.4% specificity. The model could not identify patients indifferent with the quality of their sleep (neither satisfied nor dissatisfied) (sensitivity: 0%; specificity: 100%). The accuracy of the model to predict patients dissatisfied with their sleep was 80.7%, with 83% sensitivity and 78.4% specificity. Poor physical and mental health (Domain I/II WHOQOL-Bref) as well as tinnitus distress were the strongest predictors of sleep dissatisfaction. Conversely, for sleep satisfaction, good physical and mental health as well as low tinnitus distress were the strongest predictors. The division into sleep-satisfied and sleep-dissatisfied tinnitus patients allows a very good discrimination regarding disease burden as indicated by depression, tinnitus distress, quality of life, and pain-related comorbidities. Physical and mental health as well as tinnitus distress seem to be strongly related to sleep satisfaction underscoring the concept of "tinnitus" versus "tinnitus disorder", but also the importance of sleep satisfaction as a global health indicator. Moreover, these data indicate the relevance of addressing sleep disorders in the therapeutic management of chronic tinnitus patients.

The Many Faces of Sleep Disorders in Post-Traumatic Stress Disorder: An Update on Clinical Features and Treatment

Sleep disorders and nightmares are core symptoms of post-traumatic stress disorder (PTSD). The relationship seems to be bidirectional, and persistent disturbed sleep may influence the course of the disorder. With regard to sleep quality, insomnia and nocturnal anxiety symptoms, as well as nightmares and stressful dreams, are the most prominent sleep symptoms. Polysomnographic measurements reveal alterations of the sleep architecture and fragmentation of rapid eye movement sleep. In addition, sleep disorders, such as sleep-related breathing disorders and parasomnias are frequent comorbid conditions. The complex etiology and symptomatology of trauma-related sleep disorders with frequent psychiatric comorbidity require the application of multimodal treatment concepts, including psychological and pharmacological interventions. However, there is little empirical evidence on the effectiveness of long-term drug treatment for insomnia and nightmares. For nondrug interventions, challenges arise from the current lack of PTSD-treatment concepts integrating sleep- and trauma-focused therapies. Effective therapy for sleep disturbances may consequently also improve well-being during the day and probably even the course of PTSD. Whether early sleep interventions exert a preventive effect on the development of PTSD remains to be clarified in future studies.

Restless Legs Syndrome Prevalence and Clinical Correlates Among Psychiatric Inpatients: A Multicenter Study

Background

There are only limited reports on the prevalence of restless legs syndrome (RLS) in patients with psychiatric disorders. The present study aimed to evaluate the prevalence and clinical correlates in psychiatric inpatients in Germany and Switzerland.

Methods

This is a multicenter cross-sectional study of psychiatric inpatients with an age above 18 years that were diagnosed and evaluated face-to-face using the International RLS Study Group criteria (IRLSSG) and the International RLS severity scale (IRLS). In addition to sociodemographic and biometric data, sleep quality and mood were assessed using the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI), the Epworth Sleepiness Scale (ESS), and the Patient Health Questionnaire (PHQ-9). In addition to univariate statistics used to describe and statistically analyze differences in variables of interest between patients with and without RLS, a logistic model was employed to identify predictors for the occurrence of RLS.

Results

The prevalence of RLS in a sample of 317 psychiatric inpatients was 16.4%, and 76.9% of these were diagnosed with RLS for the first time. RLS severity was moderate to severe (IRLS ± SD: 20.3 ± 8.4). The prevalences in women (p = 0.0036) and in first-degree relatives with RLS (p = 0.0108) as well as the body mass index (BMI, p = 0.0161) were significantly higher among patients with RLS, while alcohol consumption was significantly lower in the RLS group. With the exception of atypical antipsychotics, treatment with psychotropic drugs was not associated with RLS symptoms. Regarding subjective sleep quality and mood, scores of the PSQI (p = 0.0007), ISI (p = 0.0003), and ESS (p = 0.0005) were higher in patients with RLS, while PHQ-9 scores were not different. A logistic regression analysis identified gender (OR 2.67; 95% CI [1.25; 5.72]), first-degree relatives with RLS (OR 3.29; 95% CI [1.11; 9.73], ESS score (OR 1.09; 95% CI [1.01; 1.17]), and rare alcohol consumption (OR 0.45; 95% CI [0.22; 0.94] as predictors for RLS.

Conclusions

Clinically significant RLS had a high prevalence in psychiatric patients. RLS was associated with higher BMI, impaired sleep quality, and lower alcohol consumption. A systematic assessment of restless legs symptoms might contribute to improve the treatment of psychiatric patients.

A direct comparison of neuronavigated and non-neuronavigated intermittent theta burst stimulation in the treatment of depression

OBJECTIVE

To investigate whether a four-week course of neuronavigated intermittent theta burst stimulation (iTBS) of the left dorsolateral prefrontal cortex is superior to the non-neuronavigated F3-EEG method of positioning.

METHODS

We conducted a single-center, two-arm, randomized and double-blinded study (clinicaltrials.gov NCT03953521). 37 inpatients with an at least moderate depressive episode were randomized to receive either neuronavigated or 10-20-EEG-system based F3 guided iTBS. Both groups received twenty week daily sessions of iTBS while continuing to receive standard-of-care treatment by their ward physicians. For navigated iTBS, we used magnetic resonance imaging to target the border between the anterior and middle third of the middle frontal gyrus considered to represent the left dorsolateral prefrontal cortex (lDLPFC). Differences in the treatment arms were blinded by completely mimicking the procedures of the respective other treatment group. Rating physicians were not involved in the treatment procedure. Primary outcome was defined as the change of the 21-item version of the Hamilton Depression Score (HAMD) from baseline to end of treatment at week 4. Secondary outcomes included HAMD score during the treatment, Patient Health Questionnaire-9, WHO Quality of Life-BREF and Clinical Global Impression. For primary outcome, we used a planned group comparison for the absolute change in the HAMD. For secondary outcome measures we calculated analyses of variance (ANOVAs) with the within-subjects factor time (primary: baseline vs. week 4; secondary: all visits) and the between-subjects factor group (navigated vs. F3 guided group). We also did planned contrasts between both groups for all variables and all treatment and follow-up visits with the aim not to oversee any group differences. For group contrasts we used Student T-tests for metric and chi-square tests for categorial variables. Significance threshold was set to 5% uncorrected for multiple comparisons.

RESULTS

Enrolment of 80 patients with interim analysis was planned. Interim analysis was performed after 37 patients (intention to treat). 6 patients dropped out, leaving 31 for analysis. With respect to primary outcome criteria, absolute change in the HAMD did not differ significantly between groups. In accordance, relative change and number of responders and remitters were not significantly different. Overall number of responders was 53% and of remitters was 60%. On a descriptive level, the results favor the clinical effects of the F3 group for the absolute and relative change in the HAMD and the number of responders. Number of remitters were exactly the same for both groups. Therefore, we decided to stop the trial due to the added burden of magnetic resonance imaging and neuronavigated treatment in relation to the effect. Secondary outcomes did also not differ significantly between groups. Patients did not differ in their baseline characteristics nor with respect to intake of medication during the trial period and all had access to the same therapeutic interventions.

CONCLUSION

We noticed a high antidepressive effect of add-on iTBS treatment to standard inpatient treatment but failed to demonstrate a clinical superiority of neuronavigated localization. The non-navigated, F3 guided iTBS treatment used as a control group may be sophisticated enough to dilute potential added benefits, and the difference between the localization approaches is either negligible or too small to justify the additional efforts of navigation. The effects of concomitant treatment may mask effects, but our patient population reflects clinical reality in an inpatient setting. Further prospective studies are warranted to compare neuronavigated with surface-based approaches.

Computer-Assisted Avatar-Based Treatment for Dysfunctional Beliefs in Depressive Inpatients: A Pilot Study

Dysfunctional cognitions are a crucial part of depression. Cognitive therapy aims to modify dysfunctional beliefs. Typically, dysfunctional beliefs are questioned, and patients are trained to think of alternative functional beliefs. We developed a computer-assisted, avatar-based adjunct for cognitive therapy that aims to reduce dysfunctional beliefs and symptom severity. Besides, it aims to promote alternative functional beliefs. In a randomized controlled trial with 34 patients diagnosed with major depression currently undergoing inpatient treatment at the university psychiatric hospital in Regensburg, Germany, participants were randomly assigned to receive either treatment as usual (TAU) or computer-assisted avatar-based treatment for dysfunctional beliefs (CAT-DB) in addition to TAU. In CAT-DB participants are faced with a virtual avatar expressing their personal dysfunctional beliefs. Participants are asked to contradict these and express alternative functional beliefs. Assessments of conviction of dysfunctional beliefs, functional beliefs and symptom severity were done shortly before the intervention (pre-treatment), right after the intervention (post-treatment) and 14 days later (follow-up). The reduction in conviction of dysfunctional beliefs and symptom severity, and the increase in conviction of alternative functional beliefs at post-treatment and follow-up were significantly greater for the group receiving CAT-DB. Our study provides an indication in favor of the effectiveness of CAT-DB for depressive patients. It is a simple tool that could support classical cognitive therapy. Further studies at different centres, with larger sample sizes and varying therapeutic contexts are required to prove the effectiveness of our intervention.

Bifrontal high-frequency transcranial random noise stimulation is not effective as an add-on treatment in depression

BACKGROUND

Depressive disorders are linked to dysfunction in prefrontal cortical areas. Hence, non-invasive neurostimulation of the prefrontal cortex has demonstrated antidepressant efficacy. In the present study, we investigated the efficacy of high frequency transcranial random noise stimulation (hf-tRNS) as an add-on treatment for depression in a sham-controlled randomized trial.

METHODS

Forty in-patients with depression were randomized and treated with real or sham hf-tRNS (100-650 Hz) with 0 mA offset. The electrodes were mounted over the left and right dorsolateral prefrontal cortex. The Hamilton Depression Rating Scale (primary outcome), the Major Depression Inventory, the Clinical Global Impression scale and the Global Assessment of Functioning scale were used for assessment at baseline, after 3 weeks of intervention (end of treatment), and 9 weeks after intervention. Safety parameters included cognitive functioning and reported side-effects.

RESULTS

Comparison of real and sham treatment at the planned interim analysis showed an amelioration of symptoms in both groups for all outcomes with numeric but not statistically significant superiority of the sham arm for the primary outcome. Thus, the study was terminated prematurely after an interim analysis. There were no systematic differences with respect to safety parameters.

LIMITATIONS

The negative finding might be related to the specific stimulation parameters used in this study.

CONCLUSIONS

Our study suggests that prefrontal hf-tRNS is safe but not effective as an add-on treatment of depression. The challenge for future studies employing transcranial electric stimulation remains to identify effective stimulation parameters for the treatment of depression.

Sleep apnea syndrome comorbid with and without restless legs syndrome: differences in insomnia specific symptoms

OBJECTIVE

Sleep Apnea Syndrome (SAS) is frequently comorbid with Restless Legs Syndrome (RLS). Both disorders are associated with disturbed sleep. However, data about insomnia specific symptoms in patients suffering from both sleep disorders (SAS-RLS) are rare.

METHODS

In a restrospective design, we investigated 202 patients suffering from SAS and SAS-RLS. All patients underwent polysomnography, performed a vigilance test (Quatember-Maly), and completed the Regensburg Insomnia Scale (RIS), Epworth Sleepiness Scale (ESS), Beck Depression Inventory-II (BDI-II), and a Morning Questionnaire (FZN). Differences in insomnia specific symptoms between SAS and SAS-RLS were calculated using ANOVA. In a secondary analysis, the differences in daytime sleepiness and depression were analyzed.

RESULTS

Of 202 patients, 42 (21%) had SAS-RLS. The proportion of women (60%) with SASRLS was higher than for men (40%) while men had had a higher proportion (71%) of SAS alone compared to women (29%), p < 0.0005. The RIS score was higher in SAS-RLS than in SAS. No differences were found in PSG data, ESS, BDI-II, or vigilance tests.

CONCLUSIONS

Patients with both disorders SAS and RLS show a higher degree of insomnia-specific symptoms than for SAS alone and may profit from additional insomnia specific treatment.

[Recommendations on performing polygraphy or polysomnography in the fields of psychiatry and psychotherapy : Position paper of the working group on sleep medicine of the German Association for Psychiatry, Psychotherapy and Psychosomatics]

Difficulties in falling asleep and maintaining sleep, nonrestorative sleep and decreased daytime wakefulness represent very common but relatively unspecific health complaints. Around 100 specific sleep-related disorders will be classified in their own major chap. 7 (sleep wake disorders) for the first time in the upcoming 11th version of the International Classification of Diseases (ICD 11). With respect to the disciplines of psychiatry and psychotherapy there is a bidirectional relationship between mental health and sleep wake disorders. Sleep wake disorders can be an independent risk factor for the onset of a mental disorder and have a negative influence on the course of the disease. In addition, sleep wake disorders can also precede a mental disease as an early symptom and therefore be an important indication for early recognition. Many sleep wake disorders can be diagnosed based on the anamnesis and routine clinical investigations. In special cases, examination in a specialized sleep laboratory and treatment in a sleep medicine center following a staged care approach can be mandatory. Polysomnography represents the gold standard for the differential diagnostics; however, there is no legal foundation in the field of neuropsychiatric disorders for remuneration in the German healthcare system. This review summarizes the current guidelines with respect to the criteria for an investigation in a sleep laboratory from the perspective of the disciplines of psychiatry and psychotherapy. From this the requirements for guideline-conform diagnostics and treatment are derived.

Association of Chemokine (C-C Motif) Receptor 5 and Ligand 5 with Recovery from Major Depressive Disorder and Related Neurocognitive Impairment

INTRODUCTION

Inflammatory processes play an important role in the pathophysiology of major depressive disorder (MDD), but their relevance for specific symptoms such as neurocognitive impairment is rarely investigated.

METHODS

In this observational study, we investigated the changes of leukocyte chemokine (C-C motif) receptor 5 (CCR5) and ligand 5 (CCL5) mRNA levels and inflammatory cytokines in 60 MDD patients before (PRE) and after 5 weeks (W5) of antidepressive treatment in relation to therapy response and alterations in cognitive functions by means of the Cambridge Neuropsychological Test Automated Battery (CANTAB). We hypothesized that elevated CCR5 and CCL5 levels in depressed patients would decrease upon treatment and could differ with regard to cognitive impairment associated with MDD.

RESULTS

Both CCR5 and CCL5 levels were significantly decreased in the responder group compared to nonresponders even before treatment. The cytokine IL-6 as a marker of inflammation in depression did not show a difference before treatment in future responders versus nonresponders, but decreased significantly upon antidepressive therapy. Regarding neurocognitive impairment in MDD patients, an increased misperception of the emotion "anger" after 5 weeks of treatment proved to be associated with a more pronounced change in CCR5, and the perception of the emotion "disgust" became faster along with a stronger decrease in CCL5 over the same time. Executive functions typically impaired in MDD patients were not markedly associated with alterations in CCR5/CCL5.

DISCUSSION

CCR5 and CCL5 are important in the targeting of immune cells by HIV. This is the first study providing valuable hints that both CCR5 and CCL5 might also serve as markers of therapy response prediction in MDD. Regarding neurocognitive impairment in depression, CCR5 and CCL5 did not reveal characteristic changes upon MDD treatment such as executive functions, which are probably delayed. However, changes of emotional perception appear to be an earlier responding feature.

Sleep Disturbances and Suicidality in Posttraumatic Stress Disorder: An Overview of the Literature

A causal relationship between sleep disturbances and suicidal behavior has been previously reported. Insomnia and nightmares are considered as hallmarks of posttraumatic stress disorder (PTSD). In addition, patients with PTSD have an increased risk for suicidality. The present article gives an overview about the existing literature on the relationship between sleep disturbances and suicidality in the context of PTSD. It aims to demonstrate that diagnosing and treating sleep problems as still underestimated target symptoms may provide preventive strategies with respect to suicidality. However, heterogeneous study designs, different samples and diverse outcome parameters hinder a direct comparison of studies and a causal relationship cannot be shown. More research is necessary to clarify this complex relationship and to tackle the value of treatment of sleep disturbances for suicide prevention in PTSD.

Changes in Subjective-Objective Sleep Discrepancy Following Inpatient Cognitive Behavior Therapy for Insomnia

Discrepancy between objective and subjective sleep parameters is a frequent symptom in persons suffering from insomnia. Since it has an impairing effect on daytime well-being and neglects possible positive objective improvements, it would be useful if it was treated. Apart from hypnotics, cognitive behavior therapy (CBT-I) is the therapy of choice for chronic forms of insomnia. However, there is limited information about whether CBT-I can also improve subjective-objective sleep discrepancy. We investigated a large sample of patients showing chronic forms of insomnia regarding their subjective-objective sleep discrepancy pre and post CBT-I. Objective sleep data were obtained from 3 nights (2 baseline nights and 1 night after therapy) using polysomnography in our sleep laboratory. All 92 patients participated in a 14-day inpatient program with CBT-I including psychoeducation about subjective-objective sleep discrepancy. Repeated measures analyses showed an improvement in subjective-objective sleep discrepancy parameters after CBT-I. Those parameters were also correlated with perceived quality of sleep. We conclude that CBT-I is a useful tool to improve subjective-objective sleep discrepancy in patients showing chronic forms of insomnia.

[Internet-based cognitive behavioral therapy of insomnia and nightmare disorder]

Cognitive behavioral therapeutic interventions are considered to be one of the most effective forms of treatment of various mental disorders. Besides being very frequent, sleep disorders, such as insomnia and nightmare disorder are often not treated effectively and guideline-conform, mainly due to the lack of qualified psychotherapists. Implementation of modern technical options, such as web-based psychotherapy can help to overcome this problem. This article presents the current situation in the treatment of insomnia and nightmare disorders as particularly well-suited fields of application. For insomnia there are several English language and also recently German language options, which for example were also evaluated for the application to work-related stress and sleep disorders. In this respect, procedures with and without contact to a therapist or multicomponent procedures and single interventions can be differentiated. For nightmare disorders imagery rehearsal therapy provides a structure, which can also easily be transferred to an internet-based therapy program. The currently beginning use of internet-based treatment of sleep disorders does not yet utilize all theoretically available technical possibilities. The potential of internet-based therapy is extremely versatile and it remains for medical sleep experts to consider which method can be used for which indications.

Cognitive behavioral treatment for insomnia is equally effective in insomnia patients with objective short and normal sleep duration

BACKGROUND

It has been suggested that insomnia patients with short sleep duration and insomnia patients with normal sleep duration may respond differently to cognitive behavioral treatment for insomnia (CBT-I). To evaluate this hypothesis, we retrospectively examined a large sample of patients with chronic insomnia regarding their outcome post-treatment and six months after participating in a two-week standardized inpatient CBT-I program.

OBJECTIVES

Seventy-two women and 20 men with chronic insomnia received standardized inpatient CBT-I and were examined with three nights of polysomnography (two baseline nights and one post-treatment night directly following the two-week treatment). Follow-up measurements of subjective insomnia symptoms were conducted after six months. The CBT-I outcome was compared between insomnia patients with polysomnographically determined short (< 6 h) and normal (≥ 6 h) sleep duration.

RESULTS

Concerning subjective outcomes, CBT-I was equally effective in insomnia patients with objective short and normal sleep duration. Secondary analyses of polysomnographic data collected at post-treatment revealed that insomnia patients with short sleep duration showed a better treatment response in comparison to those with normal sleep duration.

CONCLUSIONS

These results suggest that the distinction in insomnia between objective short and normal sleep duration may be of limited value for treatment decisions regarding CBT-I. However, as the overall picture of the literature on this issue is not conclusive, we conclude that further prospective research is necessary to investigate the clinical validity of phenotyping insomnia patients by objective sleep data.

Emotion introspection and regulation in depression

Depressed patients suffer from an impairment to voluntarily influence and regulate their unpleasant emotional state. Strengthening the mental ability to interfere with dysfunctional emotion processing may be beneficial in treating depression. According to models of emotion processing this may be done by successful down-regulation of enhanced amygdala activity. We investigated short periods of intentional emotion-introspection compared with cognitive self-reflection as two domains of self-awareness in terms of effects on emotion regulation. Thirty depressed patients performed twelve second periods of emotion-introspection, self-reflection and a neutral condition during functional magnetic resonance imaging. We analyzed brain activation in the patients with depression by means of whole brain, region of interest and connectivity analyses. Amygdala activity decreased during emotion-introspection relative to self-reflection and to the neutral condition, whereby left amygdala was inversely activated relative to the left insula. Insula activity itself was correlated with medial and dorsolateral prefrontal cortex (PFC) activation. In conclusion, depressed patients are able to down-regulate amygdala activity by emotion-introspection. This may be interpreted as well-working emotion regulation supposedly induced by PFC connections mediated via insula. The finding supports the application of emotion-introspection, a mindfulness-related process, in a clinical setting as an element of psychotherapy to train and improve emotion regulation.

[Prevalence of sleep-related breathing disorders of inpatients with psychiatric disorders]

BACKGROUND

Sleep-related breathing disorders seriously impair well-being and increase the risk for relevant somatic and psychiatric disorders. Moreover, risk factors for sleep-related breathing disorders are highly prevalent in psychiatric patients. The aim of this study was for the first time in Germany to study the prevalence of obstructive sleep apnea syndrome (OSAS) as the most common form of sleep-related breathing disorder in patients with psychiatric disorders.

METHODS

In 10 psychiatric hospitals in Germany and 1 hospital in Switzerland, a total of 249 inpatients underwent an 8‑channel sleep polygraphy to investigate the prevalence of sleep apnea in this group of patients.

RESULTS

With a conspicuous screening result of 23.7% of the subjects, a high prevalence of sleep-related breathing disorders was found to occur among this group of patients. Male gender, higher age and high body mass index (BMI) were identified as positive risk factors for the detection of OSAS.

DISCUSSION

The high prevalence indicates that sleep apnea is a common sleep disorder among psychiatric patients. Although OSAS can lead to substantial disorders of the mental state and when untreated is accompanied by serious somatic health problems, screening procedures are not part of the routine work-up in psychiatric hospitals; therefore, sleep apnea is presumably underdiagnosed in psychiatric patients. In view of the results of this and previous studies, this topic complex should be the subject of further research studies.

Sleep after intranasal progesterone vs. zolpidem and placebo in postmenopausal women - A randomized, double-blind cross over study

CONTEXT

The loss of progesterone during menopause is linked to sleep complaints of the affected women. Previously we demonstrated sleep promoting effects of oral progesterone replacement in postmenopausal women. The oral administration of progesterone, however, is compromised by individual differences in bioavailability and metabolism of the steroid.

OBJECTIVE

We compared the sleep-endocrine effects after intranasal progesterone (MPP22), zolpidem and placebo in healthy postmenopausal women.

DESIGN

This was a randomized double-blind cross-over study.

SETTING

German monocentric study PARTICIPANTS: Participants were 12 healthy postmenopausal women.

INTERVENTIONS

Subjects received in randomized order four treatments, 2 doses of intranasal progesterone (4.5 mg and 9 mg of MPP22), 10 mg of zolpidem and placebo.

OUTCOME MEASURES

Main outcome were conventional and quantitative sleep-EEG variables. Secondary outcomes were the subjective sleep variables and the sleep related concentrations of cortisol, growth hormone (GH), melatonin and progesterone.

RESULTS

Sleep promoting effects were found after the higher dosage of MPP22 and after zolpidem. Zolpidem prompted benzodiazepine-like effects on quantitative sleep EEG as expected, whereas no such changes were found after the two dosages of MP22. Nocturnal progesterone levels increased after 9.0 mg MPP22. No other changes of hormone secretion were found.

CONCLUSIONS

Our study shows sleep promoting effects after intranasal progesterone. The spectral signature of intranasal progesterone did not resemble the sleep-EEG alterations induced by GABA active compounds. Progesterone levels were elevated after 9.0 mg MPP22. No other endocrine effects were observed.

Corticotropin-releasing hormone induces depression-like changes of sleep electroencephalogram in healthy women

We reported previously that repetitive intravenous injections of corticotropin-releasing hormone (CRH) around sleep onset prompt depression-like changes in certain sleep and endocrine activity parameters (e.g. decrease of slow-wave sleep during the second half of the night, blunted growth hormone peak, elevated cortisol concentration during the first half of the night). Furthermore a sexual dimorphism of the sleep-endocrine effects of the hormones growth hormone-releasing hormone and ghrelin was observed. In the present placebo-controlled study we investigated the effect of pulsatile administration of 4×50μg CRH on sleep electroencephalogram (EEG) and nocturnal cortisol and GH concentration in young healthy women. After CRH compared to placebo, intermittent wakefulness increased during the total night and the sleep efficiency index decreased. During the first third of the night, REM sleep and stage 2 sleep increased and sleep stage 3 decreased. Cortisol concentration was elevated throughout the night and during the first and second third of the night. GH secretion remained unchanged. Our data suggest that after CRH some sleep and endocrine activity parameters show also depression-like changes in healthy women. These changes are more distinct in women than in men.

Impact of overnight traffic noise on sleep quality, sleepiness, and vigilant attention in long-haul truck drivers: Results of a pilot study

This study aimed to evaluate the impact of traffic noise along the motorway on sleep quality, sleepiness, and vigilant attention in long-haul truck drivers. This was a randomized, crossover, within-subject controlled study. Healthy long-haul truck drivers spent 6 consecutive nights in a real truck berth with full sleep laboratory equipment. During 3 nights, subjects were exposed to replayed traffic noise alongside motorways, whereas the other 3 nights were without traffic noise. Polysomnography was recorded during the nights and numerous sleepiness tests and vigilance examinations were performed during the following standardized working day. Outcome measures were compared between noisy and silent nights using the paired Wilcoxon test. Ten healthy long-haul truck drivers with a mean age of 36.3 ± 7.3 years completed the study as planned. On noisy nights, subjects had greater latencies to the rapid eye movement (REM) phase (90 ± 32 min vs 69 ± 16 min, P = 0.074) and higher percentages of sleep stage 1 (13.7 ± 5.5% vs 11.2 ± 4.4%; P = 0.059). Subjects also rated their sleep quality as having been better during nights without noise (28.1 ± 3.7 vs 30.3 ± 6.2, P = 0.092). The impact of these differences on daytime sleepiness and vigilance was rather low; however, mean Karolinska Sleepiness Scale (KSS) scores measured during the course of the following day were higher on six out of eight occasions after noisy nights. The effects of overnight traffic noise on sleep quality are detectable but unlikely to have any major impact on the vigilant attention and driving performance of long haul-truck drivers with low nocturnal noise sensitivity. This might not be true for subgroups prone to sleeping disorders.

Gamma-hydroxybutyrate enhances mood and prosocial behavior without affecting plasma oxytocin and testosterone

Gamma-hydroxybutyrate (GHB) is a GHB-/GABAB-receptor agonist. Reports from GHB abusers indicate euphoric, prosocial, and empathogenic effects of the drug. We measured the effects of GHB on mood, prosocial behavior, social and non-social cognition and assessed potential underlying neuroendocrine mechanisms. GHB (20mg/kg) was tested in 16 healthy males, using a randomized, placebo-controlled, cross-over design. Subjective effects on mood were assessed by visual-analogue-scales and the GHB-Specific-Questionnaire. Prosocial behavior was examined by the Charity Donation Task, the Social Value Orientation test, and the Reciprocity Task. Reaction time, memory, empathy, and theory-of-mind were also tested. Blood plasma levels of GHB, oxytocin, testosterone, progesterone, dehydroepiandrosterone (DHEA), cortisol, aldosterone, and adrenocorticotropic-hormone (ACTH) were determined. GHB showed stimulating and sedating effects, and elicited euphoria, disinhibition, and enhanced vitality. In participants with low prosociality, the drug increased donations and prosocial money distributions. In contrast, social cognitive abilities such as emotion recognition, empathy, and theory-of-mind, and basal cognitive functions were not affected. GHB increased plasma progesterone, while oxytocin and testosterone, cortisol, aldosterone, DHEA, and ACTH levels remained unaffected. GHB has mood-enhancing and prosocial effects without affecting social hormones such as oxytocin and testosterone. These data suggest a potential involvement of GHB-/GABAB-receptors and progesterone in mood and prosocial behavior.

Deep Brain Stimulation for Obsessive Compulsive Disorder Reduces Symptoms of Irritable Bowel Syndrome in a Single Patient

Irritable bowel syndrome (IBS) is a frequent gastrointestinal disorder that is difficult to treat. We describe findings from evaluation of a woman (55 years old) with obsessive compulsive disorder, which was treated with bilateral deep brain stimulation in the anterior limb of the internal capsule, and IBS. After the brain stimulation treatment she reported substantial relief of her IBS symptoms. This reduction depended on specific stimulation parameters, was reproducible over time, and was not directly associated with improvements in obsessive compulsive disorder symptoms. These observations indicate a specific effect of deep brain stimulation on IBS. This observation confirms involvement of specific brain structures in the pathophysiology of IBS and shows that symptoms can be reduced through modulation of neuronal activity in the central nervous system. Further studies of the effects of brain stimulation on IBS are required.

The effect of partial sleep deprivation on computer-based measures of fitness to drive

PURPOSE

Using a partial sleep deprivation paradigm, the aim of the study was to investigate the sensitivity of a computer-based test battery of fitness to drive to detect impairments related to sleepiness.

METHODS

Forty-seven healthy subjects (34 females, mean age 26.0 ± 6.8 years) participated in a counterbalanced within-subject design of two conditions: (i) normal night sleep and (ii) partial sleep deprivation (PSD) with 4 h time in bed. For the assessment of fitness to drive, we used a validated traffic psychological test battery. Moreover, well-established measures of sleepiness highly responsive to sleep deprivation were applied: the Karolinska Sleepiness Scale (KSS), pupillography (Pupil Unrest Index (PUI) as physiological sleepiness indicator) and two sustained attention tasks (psychomotor Vigilance Task and Mackworth Clock Test).

RESULTS

Subjective and physiological sleepiness were significantly increased after PSD, accompanied by large (d > 1.50 for KSS) and medium (d = 0.55 for PUI) effect sizes. Sleepiness-related performance decrements were found in both sustained attention tasks (d = 0.59-0.77). Assessing driving-related ability, PSD induced decrements only in the test domain Reaction Test (reaction time d = 0.54 and motor time d = 0.45). All other subtests-as well as the overall judgement of fitness to drive-were not significantly affected by PSD.

CONCLUSION

In contrast to established tests of sustained attention and subjective sleepiness, computer-based test batteries of fitness to drive might lack sensitivity to core aspects of sleepiness as they mainly consist of short and stimulating subtests. Therefore, tasks that require sustained attention should be an essential part of traffic psychological test batteries when sleepiness is a potential issue.

Severe chronic insomnia is not associated with higher body mass index

Short sleep duration is widely considered to be a risk factor for weight gain, suggesting that patients suffering from sleep disorders are a risk group. Despite some positive preliminary data on patients with organic sleep disorders, empirical evidence for an increased body mass index in patients with insomnia is scarce. Two-hundred and thirty-three patients with a confirmed diagnosis of severe and chronic insomnia without co-morbidity showing objectively impaired sleep quality were compared with respect to their body mass index with control data derived from a representative population survey matched in gender and age. As a result, patients with insomnia showed a lower body mass index (23.8 kg m(-2) versus 27.1 kg m(-2) ; P < 0.0005). Our findings suggest that patients with chronic insomnia do not exhibit overweight. These data are a valuable educational tool to calm patients' fears about the consequences of insomnia, and contribute to the understanding of chronically disturbed sleep and weight regulation.

The ACDC pilot trial: targeting the anterior cingulate by double cone coil rTMS for the treatment of depression

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral-prefrontal cortex (DLPFC) with conventional figure-of-8 (=butterfly) coils has been used as an antidepressant therapeutic tool for almost twenty years. Very recently, an innovative rTMS coil, the so-called double cone coil (DC), was introduced allowing the modulation of the anterior cingulate cortex (AC). We investigated safety and therapeutic effectiveness of this stimulation in a naturalistic clinical setting.

METHOD

Forty-five patients suffering a moderate to severe depressive episode were randomized to receive 15 sessions of either conventional rTMS of the left DLPFC ("butterfly-rTMS"; 10 Hz; 2000 stimuli/day, RMT 110%), mediofrontal double cone coil stimulation of the anterior cingulate cortex ("ACDC-rTMS" with equal parameters), or sham-stimulation. The primary outcome was the change in the 21-items Hamilton Rating Scale for Depression (HAMD) from baseline to the end of treatment. Secondary outcome measures were changes over the course of the trial regarding the HAMD, the Beck Depression Inventory (BDI), the Clinical Global Impression (CGI) and the Global Assessment of Functioning (GAF) scales.

RESULTS

There was a significant group × time interaction effect regarding the primary outcome (F = 3.269; df = 2,37; P = 0.049). Post-hoc t-testing revealed a significant effect for the comparison ACDC vs. butterfly at week 3/end of treatment (T = 2.646; df = 26; P = 0.014). No severe adverse events occurred during the study. ACDC-stimulation was well tolerated by the majority of patients similar like butterfly-rTMS and sham-stimulation.

CONCLUSION

This pilot study demonstrated the feasibility of ACDC-rTMS-stimulation as an add-on-treatment for depression. Its clinical effects warrant further investigation in the future.

Impact on cortisol and antidepressant efficacy of quetiapine and escitalopram in depression

BACKGROUND

In this study, the impact of quetiapine fumarate extended release (QXR) and escitalopram (ESC) on HPA axis activity was investigated in depressed patients in relationship to antidepressant efficacy.

METHODS

In a randomized, open-label 5-week trial 60 inpatients suffering from major depression (DSM-IV criteria) were treated for 5 weeks with either QXR (300 mg/day) or ESC (10mg/day). The dexamethasone/CRH (DEX/CRH) test was performed before treatment, after 1, and after 5 weeks of treatment. Cortisol (COR) AUC values were used to assess HPA axis function. The Hamilton Depression Rating Scale was used weekly to estimate antidepressant efficacy.

RESULTS

QXR and ESC showed comparable antidepressant effects but strongly differed in their impact on HPA axis activity. In the QXR group, a marked inhibition of COR AUC levels was observed which was most pronounced after one week of treatment but showed a partial re-increase after 5 weeks of treatment. In contrast, ESC transiently stimulated COR AUC values (week 1) whereas COR AUC levels at week 0 and week 5 were comparable. COR improvement at week 1 (defined as COR peak value reduction between DEX/CRH test 1 and 2) was significantly associated with better clinical outcome.

CONCLUSION

Apparently, different effects on HPA axis activity reflect distinct pharmacoendocrinological properties of psychotropic drugs.

[Sleep medicine differential diagnostics in psychiatry and psychotherapy]

Complaints about disturbed sleep or increased daytime sleepiness are among the most frequent symptoms reported to psychiatrists by patients. Such complaints can be symptoms of an underlying psychiatric disorder or indicative of a separate or comorbid sleep disorder. Hence, basic knowledge in the differential diagnosis of sleep medicine pathologies is pivotal for psychiatrists and psychotherapists. In the present overview following a description of the diagnostic methods, the diagnostic work-up according to the major symptomatic clusters, namely disturbances in initiating and maintaining sleep, abnormal nocturnal movements and excessive daytime sleepiness will be presented.

Stress-related depression: neuroendocrine, genetic, and therapeutical aspects

OBJECTIVE

To summarize current concepts on neuroendocrine and genetic principles underlying stress-related depression and to discuss the challenges of personalized treatment in depression.

METHODS

Review of the literature pertaining to genetic and neuroendocrine basis of stress-related depression including aspects of treatment response with a focus on the hypothalamus-pituitary-adrenal (HPA) axis.

RESULTS

There is increasing evidence that genetic polymorphisms and dysregulation of the HPA axis are associated with the pathophysiology of stress-related depression. Individual stress hormone reactivity seems to be determined by a combination of genetic and environmental factors, contributing to both, resilience or vulnerability.

CONCLUSIONS

Although substantial progress has been made, current knowledge is still limited. Further basic and clinical research is needed to identify specific subgroups and to minimize heterogeneity of the depression phenotype. A better characterization is essential to detect genetic and functional predictors of antidepressant treatment response to follow the vision of personalized therapy in psychiatry.

Dreaming under antidepressants: a systematic review on evidence in depressive patients and healthy volunteers

Sleep related symptoms of depression include sleep fragmentation, early morning awakening, decreased rapid eye movement (REM) sleep latency, increased REM density, and more negative dream content. Most tricyclic antidepressants (ADs) increase total sleep time and decrease wake time after sleep onset, while many selective serotonin reuptake inhibitors (SSRIs) have an opposite effect. However, almost all ADs prolong REM sleep latency and reduce the amount of REM sleep. Case reports and research data indicate a strong effect of ADs on dream recall and dream content. We performed a systematic review (1950 to August 2010) about ADs impact on dreaming in depressive patients and healthy volunteers. Twenty-one clinical studies and 25 case reports were eligible for review and document a clear AD effect on dreaming. The major finding, both in depressed patients and in healthy volunteers, is a decrease of dream recall frequency (DRF) under ADs. This is a rather consistent effect in tricyclic ADs and phenelzine, less consistently documented also for SSRIs/serotonin norepinephrine reuptake inhibitors (SNRIs). Tricyclic ADs induce more positive dream emotions. Withdrawal from tricyclic ADs and from the monoamine oxidase inhibitors phenelzine and tranylcypromine may cause nightmares. Intake and even more withdrawal of SSRIs/SNRIs seem to intensify dreaming, which may be experienced in different ways; a potential to cause nightmares has to be taken into account. Though there are clear-cut pharmacological effects of ADs on DRF and dream content, publications have been surprisingly scarce during the past 60 years. There is evidence of a gap in neuropsychopharmacological research. AD effects on dreams should be recognized and may be used in treatment.

Reconsidering GHB: orphan drug or new model antidepressant?

For six decades, the principal mode of action of antidepressant drugs is the inhibition of monoamine re-uptake from the synaptic cleft. Tricyclic antidepressants, selective serotonin re-uptake inhibitors (SSRIs) and the new generation of dual antidepressants all exert their antidepressant effects by this mechanism. In the early days of the monoaminergic era, other efforts have been made to ameliorate the symptoms of depression by pharmacological means. The gamma-aminobutyric acid (GABA) system was and possibly still is one of the main alternative drug targets. Gammahydroxybutyrate (GHB) was developed as an orally active GABA analogue. It was tested in animal models of depression and human studies. The effects on sleep, agitation, anhedonia and depression were promising. However, the rise of benzodiazepines and tricyclic antidepressants brought GHB out of the scope of possible treatment alternatives. GHB is a GABA(B) and GHB receptor agonist with a unique spectrum of behavioural, neuroendocrine and sleep effects, and improves daytime sleepiness in various disorders such as narcolepsy, Parkinson's disease and fibromyalgia. Although it was banned from the US market at the end of the 1990s because of its abuse and overdose potential, it later was approved for the treatment of narcolepsy. New research methods and an extended view on other neurotransmitter systems as possible treatment targets of antidepressant treatment brought GHB back to the scene. This article discusses the unique neurobiological effects of GHB, its misuse potential and possible role as a model substance for the development of novel pharmacological treatment strategies in depressive disorders.

On the Need of Objective Vigilance Monitoring: Effects of Sleep Loss on Target Detection and Task-Negative Activity Using Combined EEG/fMRI

Sleep loss affects attention by reducing levels of arousal and alertness. The neural mechanisms underlying the compensatory efforts of the brain to maintain attention and performance after sleep deprivation (SD) are not fully understood. Previous neuroimaging studies of SD have not been able to separate the effects of reduced arousal from the effects of SD on cerebral responses to cognitive challenges. Here, we used a simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) approach to study the effects of 36 h of total sleep deprivation (TSD). Specifically, we focused on changes in selective attention processes as induced by an active acoustic oddball task, with the ability to isolate runs with objective EEG signs of high (SD(alert)) or reduced (SD(sleepy)) vigilance. In the SD(alert) condition, oddball task-related activity appears to be sustained by compensatory co-activation of insular regions, but task-negative activity in the right posterior node of the default mode network is altered following TSD. In the SD(sleepy) condition, oddball task-positive activity was massively impaired, but task-negative activation was showing levels comparable with the control condition after a well-rested night. Our results suggest that loss of strict negative correlation between oddball task-positive and task-negative activation reflects the effects of TSD, while the actual state of vigilance during task performance can affects either task-related or task-negative activity, depending on the exact vigilance level.

Glucose tolerance in patients with narcolepsy

STUDY OBJECTIVES

Obesity is a common feature of narcolepsy. In addition, an increased occurrence of non-insulin dependent diabetes has been reported. So far, it is not known whether glucose metabolism in narcolepsy is disturbed due to, or independently of obesity.

DESIGN

Case-control study.

SETTING

Sleep medicine clinic at a research institute.

PATIENTS

We studied 17 patients with narcolepsy/cataplexy compared to 17 healthy controls matched for age, sex, and body mass index (BMI).

INTERVENTIONS

A 75-g oral glucose tolerance test was performed.

MEASUREMENTS

Glucose tolerance was determined by computing plasma glucose curve following oral glucose challenge for 240 minutes; insulin sensitivity and insulin secretion by homeostasis model assessment and minimal model analysis.

RESULTS

Standard outcome measures and indices of the oral glucose tolerance test did not differ between the patient group and the group of control subjects.

CONCLUSIONS

In this study, no clinically relevant pathologic findings in the glucose metabolism of narcoleptic patients compared to weight matched controls were found. Thus, narcolepsy is unlikely to be a risk factor per se for impaired glucose tolerance or diabetes.

Rapid eye movements during sleep in mice: high trait-like stability qualifies rapid eye movement density for characterization of phenotypic variation in sleep patterns of rodents

Background

In humans, rapid eye movements (REM) density during REM sleep plays a prominent role in psychiatric diseases. Especially in depression, an increased REM density is a vulnerability marker for depression. In clinical practice and research measurement of REM density is highly standardized. In basic animal research, almost no tools are available to obtain and systematically evaluate eye movement data, although, this would create increased comparability between human and animal sleep studies.

Methods

We obtained standardized electroencephalographic (EEG), electromyographic (EMG) and electrooculographic (EOG) signals from freely behaving mice. EOG electrodes were bilaterally and chronically implanted with placement of the electrodes directly between the musculus rectus superior and musculus rectus lateralis. After recovery, EEG, EMG and EOG signals were obtained for four days. Subsequent to the implantation process, we developed and validated an Eye Movement scoring in Mice Algorithm (EMMA) to detect REM as singularities of the EOG signal, based on wavelet methodology.

Results

The distribution of wakefulness, non-REM (NREM) sleep and rapid eye movement (REM) sleep was typical of nocturnal rodents with small amounts of wakefulness and large amounts of NREM sleep during the light period and reversed proportions during the dark period. REM sleep was distributed correspondingly. REM density was significantly higher during REM sleep than NREM sleep. REM bursts were detected more often at the end of the dark period than the beginning of the light period. During REM sleep REM density showed an ultradian course, and during NREM sleep REM density peaked at the beginning of the dark period. Concerning individual eye movements, REM duration was longer and amplitude was lower during REM sleep than NREM sleep. The majority of single REM and REM bursts were associated with micro-arousals during NREM sleep, but not during REM sleep.

Conclusions

Sleep-stage specific distributions of REM in mice correspond to human REM density during sleep. REM density, now also assessable in animal models through our approach, is increased in humans after acute stress, during PTSD and in depression. This relationship can now be exploited to match animal models more closely to clinical situations, especially in animal models of depression.

Effects of rapid eye movement sleep deprivation on fear extinction recall and prediction error signaling

In a temporal difference learning approach of classical conditioning, a theoretical error signal shifts from outcome deliverance to the onset of the conditioned stimulus. Omission of an expected outcome results in a negative prediction error signal, which is the initial step towards successful extinction and may therefore be relevant for fear extinction recall. As studies in rodents have observed a bidirectional relationship between fear extinction and rapid eye movement (REM) sleep, we aimed to test the hypothesis that REM sleep deprivation impairs recall of fear extinction through prediction error signaling in humans. In a three-day design with polysomnographically controlled REM sleep deprivation, 18 young, healthy subjects performed a fear conditioning, extinction and recall of extinction task with visual stimuli, and mild electrical shocks during combined functional magnetic resonance imaging (fMRI) and skin conductance response (SCR) measurements. Compared to the control group, the REM sleep deprivation group had increased SCR scores to a previously extinguished stimulus at early recall of extinction trials, which was associated with an altered fMRI time-course in the left middle temporal gyrus. Post-hoc contrasts corrected for measures of NREM sleep variability also revealed between-group differences primarily in the temporal lobe. Our results demonstrate altered prediction error signaling during recall of fear extinction after REM sleep deprivation, which may further our understanding of anxiety disorders in which disturbed sleep and impaired fear extinction learning coincide. Moreover, our findings are indicative of REM sleep related plasticity in regions that also show an increase in activity during REM sleep.

Impaired glucose tolerance in sleep disorders

BACKGROUND

Recent epidemiological and experimental data suggest a negative influence of shortened or disturbed night sleep on glucose tolerance. Due to the high prevalence of sleep disorders this might be a major health issue. However, no comparative studies of carbohydrate metabolism have been conducted in clinical sleep disorders.

METHODOLOGY/PRINCIPAL FINDINGS

We performed oral glucose tolerance tests (OGTT) and assessed additional parameters of carbohydrate metabolism in patients suffering from obstructive sleep apnea syndrome (OSAS, N = 25), restless legs syndrome (RLS, N = 18) or primary insomnia (N = 21), and in healthy controls (N = 33). Compared to controls, increased rates of impaired glucose tolerance were found in OSAS (OR: 4.9) and RLS (OR: 4.7) patients, but not in primary insomnia patients (OR: 1.6). In addition, HbA1c values were significantly increased in the same two patient groups. Significant positive correlations were found between 2-h plasma glucose values measured during the OGTT and the apnea-arousal-index in OSAS (r = 0.56; p<0.05) and the periodic leg movement-arousal-index in RLS (r = 0.56, p<0.05), respectively. Sleep duration and other quantitative aspects of sleep were similar between patient groups.

CONCLUSIONS/SIGNIFICANCE

Our findings suggest that some, but not all sleep disorders considerably compromise glucose metabolism. Repeated arousals during sleep might be a pivotal causative factor deserving further experimental investigations to reveal potential novel targets for the prevention of metabolic diseases.

Successful treatment of tardive lingual dystonia with botulinum toxin: case report and review of the literature

Tardive dyskinesia (TD) is a dreaded side effect of antipsychotic medication. Recommended treatments for TD may provide reliable improvement but can be, in turn, associated with additional adverse reactions. Recently, several reports have suggested that botulinum toxin A (BTX-A) injection in affected muscles may significantly improve TD. Here, we report a case of severe tongue protrusion dystonia secondary to an antipsychotic medication in a young man. Several approaches including clozapine, amisulpride, aripiprazole, ziprasidone, tiapride and clonazepam failed to improve the symptoms. Injection of 50 U of BTX-A (Dysport, Ipsen, Ettlingen, Germany) into each genioglossal muscle dramatically improved tongue protrusion within few days with a sustained effect. If reasonable precautions are taken, the application seems to be well tolerated with only minor side effects. A review of the literature that is part of this article adverts BTX-A injection as a potential beneficial approach of various kinds of TD.