[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]. / Empfehlungen zur Durchführung einer Polygraphie oder Polysomnographie im Bereich Psychiatrie und Psychotherapie : Positionspapier des DGPPN-Referats Schlafmedizin.

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.

Serotonergic modulation of orbitofrontal activity and its relevance for decision making and impulsivity.

BACKGROUND: The orbitofrontal cortex seems to play a crucial role in reward-guided learning and decision making, especially for impulsive choice procedures including delayed reward discounting. The central serotonergic system is closely involved in the regulation of impulsivity, but how the serotonergic firing rate and release, best investigated by the loudness dependence of auditory evoked potentials (LDAEP), interact with orbitofrontal activity is still unknown. METHODS: Twenty healthy volunteers (11 males, 9 females, 31.3 ± 10.6 years old) were studied in a 3T MRI scanner (Philips, Hamburg, Germany) during a delay discounting task, after their LDAEP was recorded using a 32 electrodes EEG machine (Brain Products, Munich, Germany). RESULTS: Significant positive correlations were only found between the LDAEP and the medial orbitofrontal part of the superior frontal gyrus (SFG/MO) [Δ immediate reward - delayed reward] for the right (r = 0.519; P = 0.019) and left side (r = 0.478; P = 0.033). This relationship was stronger for females compared with males. Orbitofrontal activity was also related to the Barratt Impulsivity Scale. CONCLUSIONS: This study revealed that low serotonergic activity as measured by a strong LDAEP was related to a high fMRI signal intensity of SFG/MO during immediate reward behavior which is related to impulsivity. Since this relationship was only found for the infralimbic medial and not for the middle or lateral part of the orbitofrontal cortex, an exclusive projection tract of the serotonergic system to this cortical region can be assumed to regulate impulsive reward-orientated decision making. Hum Brain Mapp 38:1507-1517, 2017. © 2016 Wiley Periodicals, Inc.

Cortisol, platelet serotonin content, and platelet activity in patients with major depression and type 2 diabetes: an exploratory investigation.

OBJECTIVE: Hypothalamic-pituitary-adrenal system dysfunction, serotonergic system alterations, and enhanced platelet activity may contribute to the increased cardiac risk in depression. This exploratory study examined associations between cortisol parameters, platelet serotonin (5-HT) content, and platelet activity markers in patients with newly diagnosed major depression (MD) and/or Type 2 diabetes (T2DM) compared with healthy controls. METHODS: We compared cortisol awakening response (CAR), diurnal decrease in salivary cortisol concentrations (slope), platelet 5-HT, and platelet markers (CD40, CD40 ligand [CD40L], soluble CD40L, CD62P, ß-thromboglobulin, and platelet factor-4) in 22 T2DM patients, 20 MD patients, 18 T2DM patients with MD, and 24 healthy controls. RESULTS: Platelet markers were elevated in MD (F(6,60) = 11.14, p < .001) and T2DM (F(6,60) = 13.07, p < .001). Subgroups did not differ in 5-HT or cortisol slope, whereas T2DM patients without depression had significantly lower CAR than did healthy controls (F(1,61) = 7.46, p = .008). In healthy controls, cortisol slope correlated with platelet activity for CD40 (r = -0.43, p = .048) and 5-HT was correlated with CD40L (r = 0.53, p = .007). In patients with both T2DM and MD, 5-HT and CD62P were correlated (r = 0.52, p = .033). CONCLUSIONS: Increased platelet activity in T2DM and MD may play a role in the association between diabetes, depression, and coronary artery disease. The present data suggest that group differences in cortisol or 5-HT as well as group-specific associations of cortisol or 5-HT with platelet markers might be of limited importance in the shared pathways of T2DM and depression in the pathophysiology of coronary artery disease.

Depression, psychological distress, and quality of life in patients with cardioverter defibrillator with or without cardiac resynchronization therapy.

Congestive heart failure is frequent and leads to reduced exercise capacity, reduced quality of life (QoL), and depression in many patients. Cardiac resynchronization therapy (CRT) and implantable cardioverter defibrillators (ICD) offer therapeutic options and may have an impact on QoL and depression. This study was performed to evaluate physical and mental health in patients undergoing ICD or combined CRT/ICD-implantation (CRT-D). Echocardiography, spiroergometry, and psychometric questionnaires [Beck Depression Inventory, General World Health Organization Five Well-being Index (WHO-5), Brief Symptom Inventory and 36-item Short Form (SF-36)] were obtained in 39 patients (ICD: 17, CRT-D: 22) at baseline and 6-month follow-up (FU) after device implantation. CRT-D patients had a higher NYHA class and broader left bundle branch block than ICD patients at baseline. At FU, ejection fraction (EF), peak oxygen uptake, and NYHA class improved significantly in CRT-D patients but remained unchanged in ICD patients. Patients with CRT-D implantation showed higher levels of depressive symptoms, psychological distress, and impairment in QoL at baseline and FU compared to ICD patients. These impairments remained mostly unchanged in all patients after 6 months. Overall, these findings imply that there is a need for careful assessment and treatment of psychological distress and depression in ICD and CRT-D patients in the course of device implantation as psychological burden seems to persist irrespective of physical improvement.

Cross-sectional validation of the Rasch-based Depression Screening (DESC) in a mixed sample of patients with mental and somatic diseases.

BACKGROUND: The study aimed to cross-validate the psychometric properties of the two parallel versions of the "Rasch-based Depression Screening (DESC)" in a mixed clinical sample of patients with mental disorders and somatic diseases. Additionally, it was intended to confirm the initially proposed cut-off scores. METHODS: One hundred eleven inpatients from the Departments of Psychiatry (n=50), Cardiology (n=39) and Otorhinolaryngology (n=22) were examined. Accordance to Rasch model assumptions was determined by analyzing item infit and outfit as well as unidimensionality and local independence via residual principal components factor analysis (PCFA). Furthermore, separation, reliability and the targeting were considered. Differential item functioning (DIF) was investigated with regard to gender, age and clinical group. Finally, receiver operating characteristics (ROC) curves analyses were conducted and parallel test reliability was calculated. RESULTS: Item and person separation and reliability were good with separation values being above 2.90 and reliability exceeding being .90. Rasch model fit was good for all items except for the two items "sad" and "hopeless" displaying slight misfit. Targeting was appropriate with a person mean of -1.6 (DESC-I) and -1.5 (DESC-II) reflecting as expected that the two DESC versions were in average to easy for a mixed sample of patients with mental disorders and somatic. PCFA showed unidimensionality and local independence: The Rasch dimension "depression" explained 84.8% (DESC-I) and 82.2% (DESC-II) of the observed variance. No DIF was found. ROC curves confirmed the proposed cut-off score of 12 points. The area under the curve amounted to .91 for both DESC forms. The Youden index was 75.5 for DESC-I and 75.7 for DESC-II. A high parallel test reliability of .94 showed virtual equivalence of both DESC forms. CONCLUSIONS: Results of the present study support the good psychometric properties of both DESC forms in patients with mental disorders and somatic diseases. This study confirmed the cut-off scores that had already been determined in former patient samples. Thus, both DESC forms can be used validly as screening instruments for depression in clinical practice.

Loudness dependence of auditory evoked potentials (LDAEP) in clinical monitoring of suicidal patients with major depression: a pilot study.

Loudness dependence of auditory evoked potentials (LDAEP) is a validated in vivo marker of central serotonergic function. We aimed at measuring serotonergic activity in a follow-up study of suicidal patients. It should be investigated whether suicide attempts or suicidal states cause changes in the LDAEP. Thirteen patients (mean age, 40.9 ± 11.3 years; age range, 20-61, 6 male) with a major depressive episode who had attempted suicide or had suicidal plans (Hamilton Depression Rating Scale item 3 [suicidality] ≥3) were included in the study. LDAEP and psychometric measurements took place about 2, 5, 9 and 16 days after attempted suicide or suicidal action. On day 9, LDAEP was significantly higher compared to day 2 and day 16; there was a similar tendency compared to day 5. Instability of central serotonergic function is suggested resulting in reduced serotonergic activity about 1 week after suicide attempt. Further studies are necessary that include larger samples in order to distinguish between different psychiatric diseases and to consider confounding factors like gender, smoking, medication, impulsivity or lethality of suicidal action.

The loudness dependence of auditory evoked potentials and effects of psychopathology and psychopharmacotherapy in psychiatric inpatients.

OBJECTIVE: Many studies have provided evidence for the loudness dependence of auditory evoked potentials (LDAEP) as a marker for central serotonergic activity but remained inconclusive for its suitability in clinical use. METHODS: A cross-sectional sample of 162 psychiatric inpatients (major depression N = 86, bipolar disorder N = 12, schizophrenia N = 50, and schizoaffective disorder N = 14) and 40 healthy subjects was retrospectively examined for LDAEP and effects of psychopathology and psychopharmacology. RESULTS: The LDAEP was weaker in patients with affective disorders than in healthy subjects but did not differentiate between the total patient sample and healthy controls. LDAEP correlated significantly with dimensions of the Brief Symptom Inventory in the total patient sample (depression, paranoid ideation, psychoticism, Global Symptom Index, and Positive Symptom Distress Index), in patients with affective disorders (depression) and with schizophrenia spectrum disorders (depression, psychoticism, Global Symptom Index, and Positive Symptom Distress Index). Similar correlations were found in depressed patients with a single noradrenergic and specific serotonergic antidepressant or serotonin-norepinephrine reuptake inhibitor. There was a negative correlation between dosage of typical antipsychotics and LDAEP. Hypnotics generally led to a lower LDAEP. CONCLUSION: The LDAEP in patients is related to severity of psychopathologic syndromes irrespective of diagnosis. Chronic psychopharmacologic treatment may also differentially modulate the LDAEP, but longitudinal studies are needed.

Poor sleep quality is associated with depressive symptoms in patients with heart disease.

BACKGROUND: Depression in cardiac patients has gained importance due to increased mortality. Although sleep disturbances are a core symptom of depression, the prevalence and patterns of sleep disturbances in heart disease have hardly been examined regarding depression. PURPOSE: This cross-sectional study aims to examine sleep disturbances and depressive symptoms in consecutively admitted cardiac patients and depressed patients. METHODS: Two hundred four inpatients (113 male, 91 female) were examined: 94 cardiac inpatients (mean age 49.3 ± 14.3 years) with different heart diseases and 110 psychiatric inpatients (mean age 41.6 ± 13.0 years) with depressive disorders (DP). A depressive episode according to International Classification of Diseases (ICD)-10 was also diagnosed in 14 of the cardiac patients (DCP). The Pittsburgh Sleep Quality Index (PSQI) and the Beck Depression Inventory (BDI) were used to assess subjective sleep quality and severity of depressive symptoms. RESULTS: Poor sleep quality (PSQI > 5) was reported in all comorbid DCP (PSQI 12.00 ± 3.53, BDI 17.86 ± 4.28), in 60% of the 80 non-DCP (PSQI 5.59 ± 3.73, BDI 4.47 ± 3.07), and in 86.4% of the DP (PSQI 11.76 ± 4.77, BDI 27.11 ± 10.54). The cardiac inpatients showed a significant correlation between increased depressive symptoms and the PSQI components subjective sleep quality (r = 0.40) and daytime dysfunction (r = 0.34). Both sleep components were significant predictors of self-rated depression (R² = 0.404). CONCLUSIONS: Most cardiac patients experience poor sleep quality. Self-reported sleep disturbances in heart disease could serve as predictors of clinical or subclinical comorbid depression outside of a psychiatric setting in cardiology and other fields, and such patients should be referred to consultation-liaison psychiatry or polysomnography where sleep disorders like sleep apnea are suspected.

Therapeutic Landscapes and Psychiatric Care Facilities: A Qualitative Meta-Analysis.

The environment in healthcare facilities can influence health and recovery of service users and furthermore contribute to healthy workplaces for staff. The concept of therapeutic landscapes seems to be a promising approach in this context. The aim of this qualitative meta-analysis is to review the effects of therapeutic landscapes for different stakeholders in psychiatric care facilities. A systematic literature search was conducted in the four data bases PubMed, PsycInfo, CINAHL, and Web of Science. Thirteen predominately qualitative studies were included in this qualitative meta-analysis. The methodological quality of these qualitative studies was assessed, using an adapted version of the Journal Article Reporting Standards for Qualitative Research, and a thematic analysis was conducted. The results were categorised into the three main themes of the physical (built and natural), social, and symbolic dimensions of the therapeutic landscape. Given the heterogeneity of the summarised data and an overall methodological quality of the included studies that can be rated as medium, the results should be interpreted with caution. Current findings are based almost exclusively on qualitative studies. Therefore, there is a need for quantitative study designs that investigate the relationship between specific environmental elements and mental health outcomes for different stakeholders in psychiatric facilities.

Depression in patients with Huntington disease correlates with alterations of the brain stem raphe depicted by transcranial sonography.

BACKGROUND: Transcranial sonography (TCS) has become a new diagnostic tool in the evaluation of extrapyramidal disorders. Studies of TCS report alterations of the mesencephalic raphe in patients with depression. The aim of this study was to evaluate TCS findings in patients with Huntington disease in correlation with their neurologic and psychiatric status. METHODS: We recruited patients with genetically confirmed Huntington disease. The neurological and psychiatric status of participants was assessed by independent physicians. Echogenicities were investigated according to examination protocol for extrapyramidal disorders using a Siemens Sonoline Elegra system. The sonography examiner was blinded for clinical data. RESULTS: We included 39 patients in our study; 21 patients (53.8%) showed symptoms of depression at the time of evaluation and, of those, 15 (71.4%) had hypoechogenic raphe structures. Thirty patients (76.9%) had a history of depressive episodes, 19 (63.3%) of them with hypoechogenic raphe structures. All 9 patients without a history of depressive episodes showed normal echogenicity of raphe structures (sensitivity 63.3%, specificity 100%). Twelve (70.6%) of the 17 patients with Huntington disease who showed psychiatric disturbances prior to the occurrence of motor symptoms exhibited pathological raphe echogenicity (sensitivity 70.6%, specificity 68.2%). LIMITATIONS: Most of the patients were taking antichoreatic medication, which particularly influences neurologic status. Thus, a meaningful interpretation of the correlation between TCS findings and neurologic features was limited. CONCLUSION: As a novel finding, a relation between mesencephalic raphe echogenicity and depressive state could be identified in patients with Huntington disease. An alteration of the serotonergic brain stem raphe might be involved in the pathogenesis of depression in these patients.

Cognitive and affective empathy in depression linked to executive control.

Depression has been linked to executive dysfunction and emotion recognition impairments, associated with abnormalities in fronto-temporal and subcortical brain regions. Little is known about changes of different empathy subcomponents during depression, with potential impairments being related to the interpersonal difficulties of depressed patients. Twenty patients treated for an episode of unipolar depression and 20 matched healthy controls were assessed. Measures of dispositional and behavioural empathy components were administered along with tests of cognitive flexibility, response inhibition and working memory. Relative to controls, depressed patients showed higher self-reported dispositional empathy scores, mainly driven by increased personal distress scores. Patients and controls did not differ significantly in terms of behavioural cognitive empathy, empathic concern and personal affective involvement or in their executive function performance. In the patients, cognitive flexibility and response inhibition accuracy were associated with behavioural empathy. While an increased disposition towards feeling personal distress in response to other people's suffering seems to be in generally related to depressive symptoms, behavioural empathy might depend on the functional integrity of executive control during an episode of clinical depression. Impairments in this regard could contribute to the interpersonal difficulties depressed patients are frequently faced with which might have important implications for treatment.

Evaluation of basal ganglia, brainstem raphe and ventricles in bipolar disorder by transcranial sonography.

Transcranial brain sonography (TCS) has become a reliable and sensitive diagnostic tool in the evaluation of extrapyramidal movement disorders. Alterations of brainstem raphe (BR) have been depicted by TCS in major depression but not in bipolar disorder. The aim of our study was to evaluate BR echogenicity depending on the different conditions of bipolar patients. Echogenicities of dopaminergic basal ganglia structures were assessed for the first time in bipolar disorder. Thirty-six patients with bipolar I disorder (14 depressed, 8 manic, 14 euthymic) were compared to 35 healthy controls. Echogenicities were investigated according to the examination protocol for extrapyramidal disorders using a Siemens Sonoline® Elegra system. The sonography examiner was blinded for clinical rating scores. Six patients (16.7%) showed hyperechogenicity of the substantia nigra. The raphe was hypoechogenic in 13 (36.1%) of the patients. No significant differences were seen between the subgroups. Compared to the control group, frequency of altered echogenicities did not reach statistical significance. The width of third ventricle was significantly larger in the patient group (3.8±-2.1 mm vs. 2.7±1.2 mm). Depressed bipolar patients with reduced BR echogenicity showed significantly higher scores on the Hamilton Depression Rating Scale as well as the Montgomery-Åsberg Depression Rating Scale. In contrast to unipolar depression, sonographic findings of bipolar patients may generally indicate structural integrity of mesencephalic raphe structures. If bipolar disorder coexists with hypoechogenic raphe structure, depressive symptoms are more severe.

Prevalence and psychopathological characteristics of depression in consecutive otorhinolaryngologic inpatients.

BACKGROUND: High prevalence of depression has been reported in otorhinolaryngologic patients (ORL). However, studies using a semi-structured interview to determine the prevalence of depression in ORL are lacking. Therefore the present study sought to determine the depression prevalence in ORL applying a semi-structured diagnostic interview and to further characterize the pathopsychological and demographic characteristics of depression in these patients. METHODS: One-hundred inpatients of the otorhinolaryngologic department of a German university hospital participated voluntarily (age M = 38.8 years, SD = 13.9; 38.0% female). Depression was assessed using a clinical interview in which the International Diagnostic Checklist for depression (IDCL) was applied. Patients completed the Brief Symptom Inventory (BSI) which constitutes three composite scores and nine symptom scales and the Beck Depression Inventory (BDI). Multivariate analyses of variance, correlations and effect sizes were conducted. RESULTS: A prevalence of depression of 21.0% was determined, 38.0% of the depressed patients were female. Depressed patients showed higher scores on the BSI-scales "interpersonal sensitivity", "depression", "anxiety", "phobic anxiety" and "psychoticism" with medium effect sizes. CONCLUSIONS: High prevalence of depression was found which is in accordance with results of prior studies. Depressed patients showed higher psychological distress as compared to non-depressed patients. The results call for carrying on in engaging in depression research and routine depression screening in ORL.

A new electronically based clinical pathway for schizophrenia inpatients: A longitudinal pilot study.

Patients with schizophrenia, a severe chronic disorder, are characterized by resistance to therapy, lack of disease understanding, non-compliance and non-adherence, partly caused and maintained by an often poorly structured treatment strategy and polypharmacy. Treatment pathways in the sense of decision aids for professionals bring recommendations from guidelines into a clear and practice-oriented algorithm that can be a helpful tool for treatment. The aim of the present study was to assess the impact of a newly developed electronic clinical pathway (CPW) that integrates the standard computerized medical report system on symptomatic outcomes and process parameters in a population of inpatients with schizophrenia. In this randomized single-center study, 156 patients with schizophrenic disorder were treated in two groups: an experimental CPW group and a control "treatment as usual" (TAU) group. The treatment improvement was analyzed using various process parameters: the Positive and Negative Syndrome Scale (PANSS), the Clinical Global Impression scale (CGI), the Personal and Social Performance scale (PSP) and the Nurses' Observation Scale for Inpatient Evaluation (NOSIE). The CPW patients differentially showed greater improvement in psychopathology (PANSS) compared to TAU patients (t(154) = 2.030, p = 0.044). There also seems to be advantage for CPW concerning improvement in NOSIE. These results indicate a positive influence of CPW on the quality of treatment and support its implementation in daily clinical practice.

Early sensory encoding of affective prosody: neuromagnetic tomography of emotional category changes.

In verbal communication, prosodic codes may be phylogenetically older than lexical ones. Little is known, however, about early, automatic encoding of emotional prosody. This study investigated the neuromagnetic analogue of mismatch negativity (MMN) as an index of early stimulus processing of emotional prosody using whole-head magnetoencephalography (MEG). We applied two different paradigms to study MMN; in addition to the traditional oddball paradigm, the so-called optimum design was adapted to emotion detection. In a sequence of randomly changing disyllabic pseudo-words produced by one male speaker in neutral intonation, a traditional oddball design with emotional deviants (10% happy and angry each) and an optimum design with emotional (17% happy and sad each) and nonemotional gender deviants (17% female) elicited the mismatch responses. The emotional category changes demonstrated early responses (<200 ms) at both auditory cortices with larger amplitudes at the right hemisphere. Responses to the nonemotional change from male to female voices emerged later ( approximately 300 ms). Source analysis pointed at bilateral auditory cortex sources without robust contribution from other such as frontal sources. Conceivably, both auditory cortices encode categorical representations of emotional prosodic. Processing of cognitive feature extraction and automatic emotion appraisal may overlap at this level enabling rapid attentional shifts to important social cues.

Validation of the Rasch-based Depression Screening in a large scale German general population sample.

BACKGROUND: The study aimed at presenting normative data for both parallel forms of the "Rasch-based Depression Screening (DESC)", to examine its Rasch model conformity and convergent and divergent validity based on a representative sample of the German general population. METHODS: The sample was selected with the assistance of a demographic consulting company applying a face to face interview (N = 2509; mean age = 49.4, SD = 18.2; 55.8% women). Adherence to Rasch model assumptions was determined with analysis of Rasch model fit (infit and outfit), unidimensionality, local independence (principal component factor analysis of the residuals, PCFAR) and differential item functioning (DIF) with regard to participants' age and gender. Norm values were calculated. Convergent and divergent validity was determined through intercorrelations with the depression and anxiety subscales of the Hospital Anxiety and Depression Scale (HADS-D and HADS-A). RESULTS: Fit statistics were below critical values (< 1.3). There were no signs of DIF. The PCFAR revealed that the Rasch dimension "depression" explained 68.5% (DESC-I) and 69.3% (DESC-II) of the variance, respectively which suggests unidimensionality and local independence of the DESC. Correlations with HADS-D were rDESC-I = .61 and rDESC-II = .60, whereas correlations with HADS-A were rDESC-I = .62 and rDESC-II = .60. CONCLUSIONS: This study provided further support for the psychometric quality of the DESC. Both forms of the DESC adhered to Rasch model assumptions and showed intercorrelations with HADS subscales that are in line with the literature. The presented normative data offer important advancements for the interpretation of the questionnaire scores and enhance its usefulness for clinical and research applications.

Differential effects of endogenous lithium on neurobehavioural functioning: a study on auditory evoked potentials.

Lithium occurs naturally in food and water. Low environmental concentrations in drinking water are associated with mental illnesses and behavioural offences, and at therapeutic dosages it is used to treat psychiatric (especially affective) disorders, partly by facilitating serotonergic (5-HT) neurotransmission. As little is known about the psychophysiological role of nutritional lithium in the general population, endogenous lithium concentrations were hypothesised to be associated with measurable effects on emotional liability and the loudness dependence (LD) that is proposed as one of the most valid indicators of 5-HT neurotransmission. Auditory evoked potentials of healthy volunteers [N=36] with high (>2.5 microg/l) or low (<1.5 microg/l) lithium serum concentrations were recorded. Emotional liability was assessed using the Brief Symptom Inventory (BSI). Low-lithium levels correlated with Somatisation while correlations between lithium and LD were not significant. Still, LD correlated positively with Paranoid Ideation, negatively with Anxiety and, in the high-lithium group, inversely with further aspects of emotional liability (Depression, Psychological Distress). In conclusion, the effects of low levels of endogenous lithium are associated with emotional liability, and high levels with some protective effects, although findings remain inconclusive regarding LD. Potential benefits of endogenous lithium on neurobehavioural functioning, especially in high-risk individuals, would have public health implications.

Auditory mismatch negativity deficits in long-term heavy cannabis users.

Mismatch negativity (MMN) is an auditory event-related potential indicating auditory sensory memory and information processing. The present study tested the hypothesis that chronic cannabis use is associated with deficient MMN generation. MMN was investigated in age- and gender-matched chronic cannabis users (n = 30) and nonuser controls (n = 30). The cannabis users were divided into two groups according to duration and quantity of cannabis consumption. The MMNs resulting from a pseudorandomized sequence of 2 × 900 auditory stimuli were recorded by 32-channel EEG. The standard stimuli were 1,000 Hz, 80 dB SPL and 90 ms duration. The deviant stimuli differed in duration (50 ms) or frequency (1,200 Hz). There were no significant differences in MMN values between cannabis users and nonuser controls in both deviance conditions. With regard to subgroups, reduced amplitudes of frequency MMN at frontal electrodes were found in long-term (≥8 years of use) and heavy (≥15 joints/week) users compared to short-term and light users. The results indicate that chronic cannabis use may cause a specific impairment of auditory information processing. In particular, duration and quantity of cannabis use could be identified as important factors of deficient MMN generation.

Psychometric evaluation of the Rasch-based depression screening in patients with neurologic disorders.

OBJECTIVES: To provide a first evaluation of the Rasch-Based Depression Screening (DESC) in consecutive patients with neurologic disorders. DESIGN: Cross-sectional study. SETTING: Hospital specializing in neurologic disorders. PARTICIPANTS: Eligible patients (N=323; mean age +/- SD, 53.4+/-17.2y; 49.3% women) age 18 years and older. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: DESC with 2 parallel versions. RESULTS: Both versions of the DESC showed good item separation (DESC-I=4.96; DESC-II=4.94) and person separation (DESC-I=2.01; DESC-II=2.14) as well as item separation reliability (DESC-I=.96; DESC-II=.96) and person separation reliability (DESC-I=.80; DESC-II=.82). All items fit the Rasch model (infit and outfit mean squares < or =1.3). There were no signs of violation of unidimensionality. One item of DESC-I showed differential item functioning because of age and 1 item because of sex. Parallel test reliability of the 2 DESC forms was r equal to .92. CONCLUSIONS: The DESC shows good psychometric characteristics that suggest high psychometric quality of the instrument in patients with neurologic disorders. Differential item functioning on single items needs further examination but should not substantially interfere with the valid interpretation of DESC sum scores.

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.