Refine
Year of publication
Document Type
- Article (90)
- Conference Proceeding (11)
- Preprint (6)
Has Fulltext
- yes (107)
Is part of the Bibliography
- no (107)
Keywords
- ADHD (17)
- Depression (9)
- Bipolar disorder (7)
- Genetics (6)
- bipolar disorder (5)
- Human behaviour (4)
- Psychiatric disorders (4)
- Suicide (4)
- Dopamine (3)
- Neuroscience (3)
Institute
- Medizin (103)
- Psychologie (6)
- Psychologie und Sportwissenschaften (3)
- Biowissenschaften (2)
- Präsidium (1)
White matter microstructural changes and episodic memory disturbances in late-onset bipolar disorder
(2018)
Background: Bipolar disorder (BD) has been associated with distributed network disruption, but little is known on how different clinical subtypes, particularly those with an earlier and later onset of disease, are related to connectivity changes in white matter (WM) tracts.
Methods: Diffusion tensor imaging (DTI) and volumetric measures were carried out in early-onset bipolar patients [(EOD) (n = 16)], late-onset bipolar disorder [(LOD)(n = 14)] and healthy controls (n = 32). We also computed ROI analysis of gray matter (GM) and white matter (WM) volumes using the regions with significant group differences in the DTI parameters. Cognitive and behavior measurements were analyzed between groups.
Results: Lower fraction of anisotropy (FA) in the right hemisphere comprising anterior thalamic radiation, fornix, posterior cingulate, internal capsule, splenium of corpus callosum was observed in the LOD in comparison with EOD; additionally, lower FA was also found in the LOD in comparison with healthy controls, mostly in the right hemisphere and comprising fibers of the splenium of the corpus callosum, cingulum, superior frontal gyrus and posterior thalamic radiation; LOD also showed worse episodic memory performance than EOD; no statistical significant differences between mood symptoms, WM and GM volumes were found between BD groups.
Conclusion: Even after correcting for age differences, LOD was associated with more extensive WM microstructural changes and worse episodic memory performance than EOD; these findings suggest that changes in the WM fiber integrity may be associated with a later presentation of BD, possibly due to mechanisms other than neuroprogression. However, these findings deserve replication in larger, prospective, studies.
Trotz der Relevanz des Themas Suizidalität und gut bekannter Risikofaktoren gibt es bisher keine deutsche Leitlinie zur Suizidalität im Erwachsenenalter. In diesem Beitrag werden zunächst die Geschichte und die Hintergründe der Arbeit mit Leitlinien beschrieben. Der aktuelle Stand der Leitlinien für psychische Erkrankungen in Deutschland wird dargestellt und auf suizidpräventive Inhalte hin untersucht. Die Notwendigkeit evidenzbasierter Suizidprävention und einer spezifischen Leitlinie zur Suizidprävention bei Erwachsenen wird diskutiert.
Nur durch gezielte Suizidpräventionsstrategien und Interventionen für die jeweiligen Risikogruppen und unter Beachtung von Alters- und Geschlechtsspezifität kann für alle Betroffenen eine flächendeckende, gut erreichbare, bedarfs- und versorgungsgerechte, finanzierbare sowie nachhaltige medizinische Versorgung auf einem hohen Niveau sichergestellt werden. Dies gilt für den ambulanten und den stationären Bereich sowie für deren Schnittstellen. Bei Suizidalität handelt es sich um ein diagnoseübergreifendes, in unterschiedlichen Versorgungskontexten auftretendes Syndrom mit komplexem Behandlungsbedarf, weshalb intersektorale und multiprofessionelle Aspekte in einer entsprechenden Leitlinie besonders zu adressieren sind. Wissenschaftliche Evidenz und interdisziplinärer Konsens unter Expertinnen und Experten zum Umgang mit suizidalem Verhalten in der medizinischen Versorgung können dazu beitragen, Morbidität und Mortalität im Zusammenhang mit Suizidalität zu reduzieren. Im August 2021 wurde die Finanzierung einer S3-Leitlinie „Umgang mit Suizidalität“ vom Innovationsfonds des Gemeinsamen Bundesausschusses bewilligt.
Der Eintrag starker anorganischer Säuren in Wälder führte zu tiefen pH-Werten und hohen Al3+-Konzentrationen im Boden. Dem versuchte man in Deutschland seit den 1980er Jahren durch Kalkung unter Verwendung dolomitischer Kalke zu begegnen. In den ersten Jahren nach Kalkung werden organische Auflagen abgebaut und die darin enthaltenen Nährstoffe, v. a. Stickstoff (N), mobilisiert und teils im humosen Oberboden gespeichert, teils aufgenommen, teils ins Grundwasser ausgewaschen. Die Bodenvegetation reagiert auf Kalkungmit einer Zunahme an nährstoff- und stickstoffliebenden Arten, Azidophyten gehen zurück. Die Artenzusammensetzung von Mykorrhizapilzen und Bodenfauna verändern sich vollständig. Die Baumwurzeln ziehen sich in den mineralischen Oberboden zurück. Bis die basischen Kationen eine Tiefe von 30 cm erreichen, vergehen viele Jahre. Seit 1990 gingen die Depositionen an Schwefel (S) stark zurück, doch der N-Eintrag blieb bis heute auf hohem Niveau. In Nadelbaumbeständen ist der N-Eintrag wesentlich höher als in Laubwäldern oder im Freiland. Hohe N-Einträge tragen zur fortdauernden Bodenversauerung bei, zugleich eutrophieren sie Waldökosysteme, welche von Natur aus N-limitiert sind. Das verstärkte Wachstum der Waldbestände zieht einen erhöhten Bedarf an anderen Nährstoffen nach sich. In vielen Wäldern wird die kritische Belastungsgrenze („critical load“) des Eintrags von ca. 10 bis 20 kg N ha-1 a-1 überschritten. Solche Wälder werden mit N übersättigt und geben überschüssiges Nitrat, das nicht im Humus eingebaut oder von der Waldvegetation aufgenommen wird, ans Grundwasser ab. Bis heute werden in Baden-Württemberg, Rheinland-Pfalz, Hessen, Niedersachsen, Sachsen, Nordrhein-Westfalen, Thüringen und neuerdings Sachsen-Anhalt große Waldflächen mit drei bis vier Tonnen dolomitischem Kalk pro Hektar und Jahrzehnt gekalkt. Ziel ist es, eine weitere säurebedingte Verwitterung von Tonmineralen zu verhindern und die Vitalität der Waldbestände zu erhöhen. Oftmals werden dem Kalk auch Phosphor- (P) und/oder Kaliumverbindungen (K) beigemengt. Bayern, Brandenburg und Mecklenburg-Vorpommern verzichten auf Waldkalkungen oder wenden sie nur in sehr spezifischen Fällen an. Die mitteleuropäischen Hauptbaumarten Buche, Fichte, Wald-Kiefer, Tanne und Eichen sind dort ähnlich vital, da diese edaphisch eine weite ökologische Amplitude besitzen. Analysen von Blatt- und Nadelspiegeln belegen eine geringe, doch ausreichende Nährelementversorgung selbst auf den sauersten Waldböden. Heute stellt nicht Bodenversauerung, sondern N-Eutrophierung (und Klimawandel) die Hauptgefährdung der Waldökosysteme dar. Eutrophierung gefährdet die Lebensgemeinschaften auf schwach gepufferten Böden in besonderem Maße, insbesondere oligotrophe Kiefern- und Eichenwälder. Kalkung in eutrophierten Wäldern wirkt der Versauerung entgegen und führt langfristig zu tieferer Durchwurzelung. Zugleich jedoch verbessert sie angesichts hohen N-Eintrags die Verfügbarkeit limitierender Nährstoffe und verstärkt dadurch die Auswirkungen der Eutrophierung. Daher fällt die Bewertung der Kalkung ambivalent aus. Nur eine Reduzierung des N-Eintrags stellt eine wirklich gute Lösung dar. Aus Naturschutzsicht besonders bedenklich ist Waldkalkung auf natürlich basenarmen Substraten und ihren oligotraphenten Lebensgemeinschaften. Deren Habitate müssen durch Pufferzonen und angepasste Verabreichungstechniken gegen Kalkeinträge geschützt werden. Auf bestimmten mesotrophen, aber versauerungsanfälligen Lehmböden kann Kalkung fallweise toleriert werden. Die Anreicherung mit P und K entspricht einer Düngung und ist daher nicht akzeptabel. Um die Auswirkungen von Waldkalkung abwägen zu können, sollten ausreichend große ungekalkte Kontrollflächen ausgewiesen werden. Angesichts eines heute relativ hohen Waldwachstums sollte eine weitere Förderung von Waldkalkung überdacht werden.
Beyond well-established difficulties with working memory in individuals with attention deficit hyperactivity disorder (ADHD), evidence is emerging that other memory processes may also be affected. We investigated, first, which memory processes show differences in adults and adolescents with ADHD in comparison to control participants, focusing on working and short-term memory, initial learning, interference, delayed and recognition memory. Second, we investigated whether ADHD severity, co-occurring depressive symptoms, IQ and physical fitness are associated with the memory performance in the individuals with ADHD.
We assessed 205 participants with ADHD (mean age 25.8 years, SD 7.99) and 50 control participants (mean age 21.1 years, SD 5.07) on cognitive tasks including the digit span forward (DSF) and backward (DSB), the Rey Auditory Verbal Learning Test (RAVLT), and the vocabulary and matrix reasoning subtests of the Wechsler Abbreviated Scale of Intelligence. Participants with ADHD were additionally assessed on ADHD severity, depression symptoms and cardiorespiratory fitness. A series of regressions were run, with sensitivity analyses performed when variables were skewed.
ADHD-control comparisons were significant for DSF, DSB, delayed and recognition memory, with people with ADHD performing less well than the control participants. The result for recognition memory was no longer significant in sensitivity analysis. Memory performance was not associated with greater ADHD or depression symptoms severity. IQ was positively associated with all memory variables except DSF. Cardiorespiratory fitness was negatively associated with the majority of RAVLT variables.
Individuals with ADHD showed difficulties with working memory, short-term memory and delayed memory, as well as a potential difficulty with recognition memory, despite preserved initial learning.
Background: Bipolar disorder is associated with circadian disruption and a high risk of suicidal behavior. In a previous exploratory study of patients with bipolar I disorder, we found that a history of suicide attempts was associated with differences between winter and summer levels of solar insolation. The purpose of this study was to confirm this finding using international data from 42% more collection sites and 25% more countries. Methods: Data analyzed were from 71 prior and new collection sites in 40 countries at a wide range of latitudes. The analysis included 4876 patients with bipolar I disorder, 45% more data than previously analyzed. Of the patients, 1496 (30.7%) had a history of suicide attempt. Solar insolation data, the amount of the sun’s electromagnetic energy striking the surface of the earth, was obtained for each onset location (479 locations in 64 countries). Results: This analysis confirmed the results of the exploratory study with the same best model and slightly better statistical significance. There was a significant inverse association between a history of suicide attempts and the ratio of mean winter insolation to mean summer insolation (mean winter insolation/mean summer insolation). This ratio is largest near the equator which has little change in solar insolation over the year, and smallest near the poles where the winter insolation is very small compared to the summer insolation. Other variables in the model associated with an increased risk of suicide attempts were a history of alcohol or substance abuse, female gender, and younger birth cohort. The winter/summer insolation ratio was also replaced with the ratio of minimum mean monthly insolation to the maximum mean monthly insolation to accommodate insolation patterns in the tropics, and nearly identical results were found. All estimated coefficients were significant at p < 0.01. Conclusion: A large change in solar insolation, both between winter and summer and between the minimum and maximum monthly values, may increase the risk of suicide attempts in bipolar I disorder. With frequent circadian rhythm dysfunction and suicidal behavior in bipolar disorder, greater understanding of the optimal roles of daylight and electric lighting in circadian entrainment is needed.
Background: Recently, RBFOX1, a gene encoding an RNA binding protein, has consistently been associated with aggressive and antisocial behavior. Several loci in the gene have been nominally associated with aggression in genome-wide association studies, the risk alleles being more frequent in the general population. We have hence examined the association of four RBFOX1 single nucleotide polymorphisms, previously found related to aggressive traits, with aggressiveness, personality, and alcohol use disorder in birth cohort representative samples.
Methods: We used both birth cohorts of the Estonian Children Personality Behavior and Health Study (ECPBHS; original n = 1,238). Aggressiveness was assessed using the Buss–Perry Aggression Questionnaire and the Lifetime History of Aggressiveness structured interview at age 25 (younger cohort) or 33 (older cohort). Big Five personality at age 25 was measured with self-reports and the lifetime occurrence of alcohol use disorder assessed with the MINI interview. RBFOX1 polymorphisms rs809682, rs8062784, rs12921846, and rs6500744 were genotyped in all participants. Given the restricted size of the sample, correction for multiple comparisons was not applied.
Results: Aggressiveness was not significantly associated with the RBFOX1 genotype. RBFOX1 rs8062784 was associated with neuroticism and rs809682 with extraversion. Two out of four analyzed RBFOX1 variants, rs8062784 and rs12921846, were associated with the occurrence of alcohol use disorder.
Conclusions: In the birth cohort representative sample of the ECPBHS, no association of RBFOX1 with aggressiveness was found, but RBFOX1 variants affected basic personality traits and the prevalence of alcohol use disorder. Future studies on RBFOX1 should consider the moderating role of personality and alcohol use patterns in aggressiveness.
Einführung: Seit 20 Jahren ist die Vagusnervstimulation (VNS) eine europaweit zugelassene invasive Therapieoption für therapieresistente Depressionen (TRD). Im Gegensatz zu geläufigeren Behandlungen wie EKT sind Kenntnisse über VNS sowohl in der Allgemeinbevölkerung als auch in Fachkreisen gering.
Methoden: In diesem narrativen Review geben wir eine klinisch und wissenschaftlich fundierte Übersicht über die VNS. Hypothesen zum Wirkmechanismus sowie die aktuelle Evidenzlage zur Wirksamkeit werden dargestellt. Das perioperative Management, das Nebenwirkungsprofil und die Nachbetreuung einschließlich Dosistitration werden beschrieben. Ein Vergleich über internationale Leitlinienempfehlungen zur VNS findet sich ebenfalls. Ferner formulieren wir Kriterien, die bei der Auswahl geeigneter Patienten hilfreich sind.
Ergebnisse: Die elektrischen Impulse werden über den N. vagus afferent weitergeleitet und stimulieren über verschiedene Wege ein neuromodulatorisches zerebrales Netzwerk. Viele Studien und Fallserien zeigten die Wirksamkeit von VNS als adjuvantes Verfahren bei TRD. Der Effekt tritt mit einer Latenz von 3 bis 12 Monaten ein und steigt möglicherweise mit der Dauer der VNS. Unter der Beachtung der Stimulationsempfehlungen sind die Nebenwirkungen für die meisten Patienten tolerabel.
Fazit: Die VNS ist eine zugelassene, wirksame und gut verträgliche Langzeittherapie für chronische und therapieresistente Depressionen. Weitere Sham-kontrollierte Studien über einen längeren Beobachtungszeitraum sind zur Verbesserung der Evidenz wünschenswert.
Transdiagnostic comparison of visual working memory capacity in bipolar disorder and schizophrenia
(2021)
Background: Impaired working memory is a core cognitive deficit in both bipolar disorder and schizophrenia. Its study might yield crucial insights into the underpinnings of both disorders on the cognitive and neurophysiological level. Visual working memory capacity is a particularly promising construct for such translational studies. However, it has not yet been investigated across the full spectrum of both disorders. The aim of our study was to compare the degree of reductions of visual working memory capacity in patients with bipolar disorder (PBD) and patients with schizophrenia (PSZ) using a paradigm well established in cognitive neuroscience.
Methods: 62 PBD, 64 PSZ, and 70 healthy controls (HC) completed a canonical visual change detection task. Participants had to encode the color of four circles and indicate after a short delay whether the color of one of the circles had changed or not. We estimated working memory capacity using Pashler’s K.
Results: Working memory capacity was significantly reduced in both PBD and PSZ compared to HC. We observed a small effect size (r = .202) for the difference between HC and PBD and a medium effect size (r = .370) for the difference between HC and PSZ. Working memory capacity in PSZ was also significantly reduced compared to PBD with a small effect size (r = .201). Thus, PBD showed an intermediate level of impairment.
Conclusions: These findings provide evidence for a gradient of reduced working memory capacity in bipolar disorder and schizophrenia, with PSZ showing the strongest degree of impairment. This underscores the importance of disturbed information processing for both bipolar disorder and schizophrenia. Our results are compatible with the cognitive manifestation of a neurodevelopmental gradient affecting bipolar disorder to a lesser degree than schizophrenia. They also highlight the relevance of visual working memory capacity for the development of both behavior- and brain-based transdiagnostic biomarkers.
Highlights
• A panel of 20 biomarkers was identified capable of differentiating BD patients from controls.
• Excellent discrimination between established BD patients and controls.
• Good to excellent discrimination between misdiagnosed BD patients and first onset MDD patients.
• Fair to good discrimination between pre-diagnostic BD patients and controls.
• Study demonstrates the potential utility of a protein biomarker panel as a diagnostic test for BD.
Abstract
Background: Bipolar disorder (BD) is a costly, devastating and life shortening mental disorder that is often misdiagnosed, especially on initial presentation. Misdiagnosis frequently results in ineffective treatment. We investigated the utility of a biomarker panel as a diagnostic test for BD.
Methods and findings: We performed a meta-analysis of eight case-control studies to define a diagnostic biomarker panel for BD. After validating the panel on established BD patients, we applied it to undiagnosed BD patients. We analysed 249 BD, 122 pre-diagnostic BD, 75 pre-diagnostic schizophrenia and 90 first onset major depression disorder (MDD) patients and 371 controls. The biomarker panel was identified using ten-fold cross-validation with lasso regression applied to the 87 analytes available across the meta-analysis studies.
We identified 20 protein analytes with excellent predictive performance [area under the curve (AUC) ⩾ 0.90]. Importantly, the panel had a good predictive performance (AUC 0.84) to differentiate 12 misdiagnosed BD patients from 90 first onset MDD patients, and a fair to good predictive performance (AUC 0.79) to differentiate between 110 pre-diagnostic BD patients and 184 controls. We also demonstrated the disease specificity of the panel.
Conclusions: An early and accurate diagnosis has the potential to delay or even prevent the onset of BD. This study demonstrates the potential utility of a biomarker panel as a diagnostic test for BD.
Isolated generalized dystonia is a central motor network disorder characterized by twisted movements or postures. The most frequent genetic cause is a GAG deletion in the Tor1a (DYT1) gene encoding torsinA with a reduced penetrance of 30-40 % suggesting additional genetic or environmental modifiers. Development of dystonia-like movements after a standardized peripheral nerve crush lesion in wild type (wt) and Tor1a+/- mice, that express 50 % torsinA only, was assessed by scoring of hindlimb movements during tail suspension, by rotarod testing and by computer-assisted gait analysis. Western blot analysis was performed for dopamine transporter (DAT), D1 and D2 receptors from striatal and quantitative RT-PCR analysis for DAT from midbrain dissections. Autoradiography was used to assess the functional DAT binding in striatum. Striatal dopamine and its metabolites were analyzed by high performance liquid chromatography. After nerve crush injury, we found abnormal posturing in the lesioned hindlimb of both mutant and wt mice indicating the profound influence of the nerve lesion (15x vs. 12x relative to control) resembling human peripheral pseudodystonia. In mutant mice the phenotypic abnormalities were increased by about 40 % (p < 0.05). This was accompanied by complex alterations of striatal dopamine homeostasis. Pharmacological blockade of dopamine synthesis reduced severity of dystonia-like movements, whereas treatment with L-Dopa aggravated these but only in mutant mice suggesting a DYT1 related central component relevant to the development of abnormal involuntary movements. Our findings suggest that upon peripheral nerve injury reduced torsinA concentration and environmental stressors may act in concert in causing the central motor network dysfunction of DYT1 dystonia.