TY  - JOUR
A1  - Taurines, R.
A1  - Fekete, S.
A1  - Preuss-Wiedenhoff, A.
A1  - Warnke, A.
A1  - Wewetzer, C.
A1  - Plener, P.
A1  - Burger, R.
A1  - Gerlach, M.
A1  - Romanos, M.
A1  - Egberts, K. M.
T1  - Therapeutic drug monitoring in children and adolescents with schizophrenia and other psychotic disorders using risperidone
JF  - Journal of Neural Transmission
N2  - Risperidone is commonly used to treat different psychiatric disorders worldwide. Knowledge on dose–concentration relationships of risperidone treatment in children and adolescents with schizophrenia or other psychotic disorders is, however, scarce and no age-specific therapeutic ranges have been established yet. Multicenter data of a therapeutic drug monitoring service were analyzed to evaluate the relationship between risperidone dose and serum concentration of the active moiety (risperidone (RIS) plus its main metabolite 9-hydroxyrisperidone (9-OH-RIS)) in children and adolescents with psychotic disorders. Patient characteristics, doses, serum concentrations and therapeutic outcomes were assessed by standardized measures. The study also aimed to evaluate whether the therapeutic reference range for adults (20–60 ng/ml) is applicable for minors. In the 64 patients (aged 11–18 years) included, a positive correlation between daily dose and the active moiety (RIS\(_{am}\)) concentration was found (r\(_s\) = 0.49, p = 0.001) with variation in dose explaining 24% (r\(_s\)\(^2\) = 0.240) of the variability in serum concentrations. While the RIS\(_{am}\) concentration showed no difference, RIS as well 9-OH-RIS concentrations and the parent to metabolite ratio varied significantly in patients with co-medication of a CYP2D6 inhibitor. Patients with extrapyramidal symptoms (EPS) had on average higher RIS\(_{am}\) concentrations than patients without (p = 0.05). Considering EPS, the upper threshold of the therapeutic range of RIS\(_{am}\) was determined to be 33 ng/ml. A rough estimation method also indicated a possibly decreased lower limit of the preliminary therapeutic range in minors compared to adults. These preliminary data may contribute to the definition of a therapeutic window in children and adolescents with schizophrenic disorders treated with risperidone. TDM is recommended in this vulnerable population to prevent concentration-related adverse drug reactions.
KW  - risperidone
KW  - children
KW  - serum concentration
KW  - schizophrenia
KW  - therapeutic drug monitoring
KW  - pharmacovigilance
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324833
VL  - 129
IS  - 5-6
ER  - 
TY  - JOUR
A1  - Schmitt, Andrea
A1  - Tatsch, Laura
A1  - Vollhardt, Alisa
A1  - Schneider-Axmann, Thomas
A1  - Raabe, Florian J.
A1  - Roell, Lukas
A1  - Heinsen, Helmut
A1  - Hof, Patrick R.
A1  - Falkai, Peter
A1  - Schmitz, Christoph
T1  - Decreased oligodendrocyte number in hippocampal subfield CA4 in schizophrenia: a replication study
JF  - Cells
N2  - Hippocampus-related cognitive deficits in working and verbal memory are frequent in schizophrenia, and hippocampal volume loss, particularly in the cornu ammonis (CA) subregions, was shown by magnetic resonance imaging studies. However, the underlying cellular alterations remain elusive. By using unbiased design-based stereology, we reported a reduction in oligodendrocyte number in CA4 in schizophrenia and of granular neurons in the dentate gyrus (DG). Here, we aimed to replicate these findings in an independent sample. We used a stereological approach to investigate the numbers and densities of neurons, oligodendrocytes, and astrocytes in CA4 and of granular neurons in the DG of left and right hemispheres in 11 brains from men with schizophrenia and 11 brains from age- and sex-matched healthy controls. In schizophrenia, a decreased number and density of oligodendrocytes was detected in the left and right CA4, whereas mean volumes of CA4 and the DG and the numbers and density of neurons, astrocytes, and granular neurons were not different in patients and controls, even after adjustment of variables because of positive correlations with postmortem interval and age. Our results replicate the previously described decrease in oligodendrocytes bilaterally in CA4 in schizophrenia and point to a deficit in oligodendrocyte maturation or a loss of mature oligodendrocytes. These changes result in impaired myelination and neuronal decoupling, both of which are linked to altered functional connectivity and subsequent cognitive dysfunction in schizophrenia.
KW  - schizophrenia
KW  - hippocampus
KW  - CA4
KW  - dentate gyrus
KW  - postmortem
KW  - stereology
KW  - oligodendrocyte
KW  - neuron
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-290360
SN  - 2073-4409
VL  - 11
IS  - 20
ER  - 
TY  - JOUR
A1  - Meier, Sandra M.
A1  - Kähler, Anna K.
A1  - Bergen, Sarah E.
A1  - Sullivan, Patrick F.
A1  - Hultman, Christina M.
A1  - Mattheisen, Manuel
T1  - Chronicity and Sex Affect Genetic Risk Prediction in Schizophrenia
JF  - Frontiers in Psychiatry
N2  - Schizophrenia (SCZ) is a severe mental disorder with immense personal and societal costs; identifying individuals at risk is therefore of utmost importance. Genomic risk profile scores (GRPS) have been shown to significantly predict cases-control status. Making use of a large-population based sample from Sweden, we replicate a previous finding demonstrating that the GRPS is strongly associated with admission frequency and chronicity of SCZ. Furthermore, we were able to show a substantial gap in prediction accuracy between males and females. In sum, our results indicate that prediction accuracy by GRPS depends on clinical and demographic characteristics.
KW  - schizophrenia
KW  - polygenic risk score
KW  - prediction
KW  - sex
KW  - course
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-205677
SN  - 1664-0640
VL  - 11
ER  - 
TY  - JOUR
A1  - Isles, Anthony R.
A1  - Ingason, Andrés
A1  - Lowther, Chelsea
A1  - Walters, James
A1  - Gawlick, Micha
A1  - Stöber, Gerald
A1  - Rees, Elliott
A1  - Martin, Joanna
A1  - Little, Rosie B.
A1  - Potter, Harry
A1  - Georgieva, Lyudmila
A1  - Pizzo, Lucilla
A1  - Ozaki, Norio
A1  - Aleksic, Branko
A1  - Kushima, Itaru
A1  - Ikeda, Masashi
A1  - Iwata, Nakao
A1  - Levinson, Douglas F.
A1  - Gejman, Pablo V.
A1  - Shi, Jianxin
A1  - Sanders, Alan R.
A1  - Duan, Jubao
A1  - Willis, Joseph
A1  - Sisodiya, Sanjay
A1  - Costain, Gregory
A1  - Werge, Thomas M.
A1  - Degenhardt, Franziska
A1  - Giegling, Ina
A1  - Rujescu, Dan
A1  - Hreidarsson, Stefan J.
A1  - Saemundsen, Evald
A1  - Ahn, Joo Wook
A1  - Ogilvie, Caroline
A1  - Girirajan, Santhosh D.
A1  - Stefansson, Hreinn
A1  - Stefansson, Kari
A1  - O'Donovan, Michael C.
A1  - Owen, Michael J.
A1  - Bassett, Anne
A1  - Kirov, George
T1  - Parental Origin of Interstitial Duplications at 15q11.2-q13.3 in Schizophrenia and Neurodevelopmental Disorders
JF  - PLoS Genetics
N2  - Duplications at 15q11.2-q13.3 overlapping the Prader-Willi/Angelman syndrome (PWS/AS) region have been associated with developmental delay (DD), autism spectrum disorder (ASD) and schizophrenia (SZ). Due to presence of imprinted genes within the region, the parental origin of these duplications may be key to the pathogenicity. Duplications of maternal origin are associated with disease, whereas the pathogenicity of paternal ones is unclear. To clarify the role of maternal and paternal duplications, we conducted the largest and most detailed study to date of parental origin of 15q11.2-q13.3 interstitial duplications in DD, ASD and SZ cohorts. We show, for the first time, that paternal duplications lead to an increased risk of developing DD/ASD/multiple congenital anomalies (MCA), but do not appear to increase risk for SZ. The importance of the epigenetic status of 15q11.2-q13.3 duplications was further underlined by analysis of a number of families, in which the duplication was paternally derived in the mother, who was unaffected, whereas her offspring, who inherited a maternally derived duplication, suffered from psychotic illness. Interestingly, the most consistent clinical characteristics of SZ patients with 15q11.2-q13.3 duplications were learning or developmental problems, found in 76% of carriers. Despite their lower pathogenicity, paternal duplications are less frequent in the general population with a general population prevalence of 0.0033% compared to 0.0069% for maternal duplications. This may be due to lower fecundity of male carriers and differential survival of embryos, something echoed in the findings that both types of duplications are de novo in just over 50% of cases. Isodicentric chromosome 15 (idic15) or interstitial triplications were not observed in SZ patients or in controls. Overall, this study refines the distinct roles of maternal and paternal interstitial duplications at 15q11.2-q13.3, underlining the critical importance of maternally expressed imprinted genes in the contribution of Copy Number Variants (CNVs) at this interval to the incidence of psychotic illness. This work will have tangible benefits for patients with 15q11.2-q13.3 duplications by aiding genetic counseling.
KW  - interstitial duplications
KW  - schizophrenia
KW  - developmental delay
KW  - autism spectrum disorder
KW  - parental origin
KW  - genetics
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166706
VL  - 12
IS  - 5
ER  - 
TY  - JOUR
A1  - van de Kerkhof, Nora WA
A1  - Fekkes, Durk
A1  - van der Heijden, Frank MMA
A1  - Hoogendijk, Witte JG
A1  - Stöber, Gerald
A1  - Egger, Jos IM
A1  - Verhoeven, Willem MA
T1  - Cycloid psychoses in the psychosis spectrum: evidence for biochemical differences with schizophrenia
JF  - Neuropsychiatric Disease and Treatment
N2  - Cycloid psychoses (CP) differ from schizophrenia regarding symptom profile, course, and prognosis and over many decades they were thought to be a separate entity within the psychosis spectrum. As to schizophrenia, research into the pathophysiology has focused on dopamine, brain-derived neurotrophic factor, and glutamate signaling in which, concerning the latter, the N-methyl-d-aspartate receptor plays a crucial role. The present study aims to determine whether CP can biochemically be delineated from schizophrenia. Eighty patients referred for psychotic disorders were assessed with the Comprehensive Assessment of Symptoms and History, and (both at inclusion and after 6 weeks of antipsychotic treatment) with the Positive and Negative Syndrome Scale and Clinical Global Impression. From 58 completers, 33 patients were diagnosed with schizophrenia and ten with CP according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and Leonhard criteria, respectively. Fifteen patients were diagnosed with other disorders within the psychosis spectrum. At both time points, blood levels of the dopamine metabolite homovanillic acid, brain-derived neurotrophic factor, and amino acids related to glutamate neurotransmission were measured and compared with a matched control sample. Patients with CP showed a significantly better response to antipsychotic treatment as compared to patients with schizophrenia. In CP, glycine levels were elevated and tryptophan levels were lowered as compared to schizophrenia. Glutamate levels were increased in both patient groups as compared to controls. These results, showing marked differences in both treatment outcome and glutamate-related variable parameters, may point at better neuroplasticity in CP, necessitating demarcation of this subgroup within the psychosis spectrum.
KW  - cycloid psychoses
KW  - schizophrenia
KW  - glutamate
KW  - glycine
KW  - tryptophan
KW  - neuroplasticity
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166255
VL  - 12
ER  - 
TY  - JOUR
A1  - van de Kerkhof, Noortje W. A.
A1  - van der Heijden, Frank M. M. A.
A1  - Schneider, Marc K. F.
A1  - Pfuhlmann, Bruno
A1  - Stöber, Gerald
A1  - Egger, Jos I. M.
A1  - Verhoeven, Willem M. A.
T1  - Cycloid psychoses: Leonhard's descriptions revisited
JF  - European Journal of Psychiatry
N2  - Background and Objectives: Cycloid psychoses are characterized by polymorphic symptomatology with intraphasic bipolarity, a remitting and recurrent course and favourable prognosis. Perris and Brocicington (P&B) described the first set of operational criteria that were partly incorporated in ICD-10. The present study investigates psychopathological profiles according to the P&B criteria and the original descriptions by Leonhard, both against the background of the criteria from the prevailing international classification systems. 
Methods: Eighty patients with psychotic disorders were recruited and assessed with various psychometric instruments at baseline and after six weeks of antipsychotic treatment in order to investigate the presence of cycloid psychoses according to Leonhard (LCP) and the effect of treatment with antipsychotics. The overlap between LCP and DSM-IV Brief Psychotic Disorder (BPD), ICD Acute Polymorphic Psychotic Disorder (APP) and P&B criteria was calculated. 
Results: Using P&B criteria and a symptom checklist adapted from the original descriptions by Leonhard, 14 and 12 cases of cycloid psychosis were identified respectively reflecting a prevalence of 15-18%. Small though significant concordance rates were found between LCP and both DSM-BPD and ICD-APP. Concordance between LCP and P&B criteria was also significant, but modest. 
Conclusions: This study demonstrates that LCP can be identified in a substantial number of patients with psychotic disorders. Cycloid psychoses are not adequately covered in current classification systems and criteria. Since they are demonstrated to have a specific psychopathological profile, relapsing course and favourable prognosis, it is advocated to include these psychoses in daily differential diagnostic procedures.
KW  - P300
KW  - endogenous psychoses
KW  - follow-up
KW  - schizophrenia
KW  - disorder
KW  - classification
KW  - validity
KW  - family
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-134779
VL  - 26
IS  - 4
ER  - 
TY  - JOUR
A1  - Van de Kerkhof, Noortje W. A.
A1  - Feenstra, Ilse
A1  - van der Heijden, Frank M. M. A.
A1  - de Leeuw, Nicole
A1  - Pfundt, Rolph
A1  - Stöber, Gerald
A1  - Egger, Jos I. M.
A1  - Verhoeven, Willem M. A.
T1  - Copy number variants in a sample of patients with psychotic disorders: is standard screening relevant for actual clinical practice?
JF  - Neuropsychiatric Disease and Treatment
N2  - With the introduction of new genetic techniques such as genome-wide array comparative genomic hybridization, studies on the putative genetic etiology of schizophrenia have focused on the detection of copy number variants (CNVs), ie, microdeletions and/or microduplications, that are estimated to be present in up to 3% of patients with schizophrenia. In this study, out of a sample of 100 patients with psychotic disorders, 80 were investigated by array for the presence of CNVs. The assessment of the severity of psychiatric symptoms was performed using standardized instruments and ICD-10 was applied for diagnostic classification. In three patients, a submicroscopic CNV was demonstrated, one with a loss in 1q21.1 and two with a gain in 1p13.3 and 7q11.2, respectively. The association between these or other CNVs and schizophrenia or schizophrenia-like psychoses and their clinical implications still remain equivocal. While the CNV affected genes may enhance the vulnerability for psychiatric disorders via effects on neuronal architecture, these insights have not resulted in major changes in clinical practice as yet. Therefore, genome-wide array analysis should presently be restricted to those patients in whom psychotic symptoms are paired with other signs, particularly dysmorphisms and intellectual impairment.
KW  - microarrays
KW  - spectrum disorders
KW  - schizophrenia
KW  - gene
KW  - psychopathology
KW  - polymorphisms
KW  - microdeletion
KW  - perspectives
KW  - association
KW  - environment
KW  - copy number variants
KW  - 1q21
KW  - 7q11.2
KW  - 1p13.3
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-134769
VL  - 8
ER  - 
TY  - JOUR
A1  - Biernacka, J. M.
A1  - Sangkuhl, K.
A1  - Jenkins, G.
A1  - Whaley, R. M.
A1  - Barman, P.
A1  - Batzler, A.
A1  - Altman, R. B.
A1  - Arolt, V.
A1  - Brockmöller, J.
A1  - Chen, C. H.
A1  - Domschke, K.
A1  - Hall-Flavin, D. K.
A1  - Hong, C. J.
A1  - Illi, A.
A1  - Ji, Y.
A1  - Kampman, O.
A1  - Kinoshita, T.
A1  - Leinonen, E.
A1  - Liou, Y. J.
A1  - Mushiroda, T.
A1  - Nonen, S.
A1  - Skime, M. K.
A1  - Wang, L.
A1  - Baune, B. T.
A1  - Kato, M.
A1  - Liu, Y. L.
A1  - Praphanphoj, V.
A1  - Stingl, J. C.
A1  - Tsai, S. J.
A1  - Kubo, M.
A1  - Klein, T. E.
A1  - Weinshilboum, R.
T1  - The International SSRI Pharmacogenomics Consortium (ISPC): a genome-wide association study of antidepressant treatment response
JF  - Translational Psychiatry
N2  - Response to treatment with selective serotonin reuptake inhibitors (SSRIs) varies considerably between patients. The International SSRI Pharmacogenomics Consortium (ISPC) was formed with the primary goal of identifying genetic variation that may contribute to response to SSRI treatment of major depressive disorder. A genome-wide association study of 4-week treatment outcomes, measured using the 17-item Hamilton Rating Scale for Depression (HRSD-17), was performed using data from 865 subjects from seven sites. The primary outcomes were percent change in HRSD-17 score and response, defined as at least 50% reduction in HRSD-17. Data from two prior studies, the Pharmacogenomics Research Network Antidepressant Medication Pharmacogenomics Study (PGRN-AMPS) and the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study, were used for replication, and a meta-analysis of the three studies was performed (N = 2394). Although many top association signals in the ISPC analysis map to interesting candidate genes, none were significant at the genome-wide level and the associations were not replicated using PGRN-AMPS and STAR*D data. Top association results in the meta-analysis of response included single-nucleotide polymorphisms (SNPs) in the HPRTP4 (hypoxanthine phosphoribosyltransferase pseudogene 4)/VSTM5 (V-set and transmembrane domain containing 5) region, which approached genome-wide significance (P = 5.03E - 08) and SNPs 5' upstream of the neuregulin-1 gene, NRG1 (P = 1.20E - 06). NRG1 is involved in many aspects of brain development, including neuronal maturation and variations in this gene have been shown to be associated with increased risk for mental disorders, particularly schizophrenia. Replication and functional studies of these findings are warranted.
KW  - major depressive disorder
KW  - genetic variation
KW  - schizophrenia
KW  - neuregulin-1
KW  - population
KW  - microcephalin 1
KW  - susceptibility
KW  - metaanalysis
KW  - MCPH1
KW  - loci
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-143223
VL  - 5
IS  - e553
ER  - 
TY  - JOUR
A1  - Kohl, S.
A1  - Gruendler, T. O. J.
A1  - Huys, D.
A1  - Sildatke, E.
A1  - Dembek, T. A.
A1  - Hellmich, M.
A1  - Vorderwulbecke, M.
A1  - Timmermann, L.
A1  - Ahmari, S. E.
A1  - Klosterkoetter, J.
A1  - Jessen, F.
A1  - Sturm, V.
A1  - Visser-Vandewalle, V.
A1  - Kuhn, J.
T1  - Effects of deep brain stimulation on prepulse inhibition in obsessive-compulsive disorder
JF  - Translational Psychiatry
N2  - Owing to a high response rate, deep brain stimulation (DBS) of the ventral striatal area has been approved for treatment-refractory obsessive-compulsive disorder (tr-OCD). Many basic issues regarding DBS for tr-OCD are still not understood, in particular, the mechanisms of action and the origin of side effects. We measured prepulse inhibition (PPI) in treatment-refractory OCD patients undergoing DBS of the nucleus accumbens (NAcc) and matched controls. As PPI has been used in animal DBS studies, it is highly suitable for translational research. Eight patients receiving DBS, eight patients with pharmacological treatment and eight age-matched healthy controls participated in our study. PPI was measured twice in the DBS group: one session with the stimulator switched on and one session with the stimulator switched off. OCD patients in the pharmacologic group took part in a single session. Controls were tested twice, to ensure stability of data. Statistical analysis revealed significant differences between controls and (1) patients with pharmacological treatment and (2) OCD DBS patients when the stimulation was switched off. Switching the stimulator on led to an increase in PPI at a stimulus-onset asynchrony of 200 ms. There was no significant difference in PPI between OCD patients being stimulated and the control group. This study shows that NAcc-DBS leads to an increase in PPI in tr-OCD patients towards a level seen in healthy controls. Assuming that PPI impairments partially reflect the neurobiological substrates of OCD, our results show that DBS of the NAcc may improve sensorimotor gating via correction of dysfunctional neural substrates. Bearing in mind that PPI is based on a complex and multilayered network, our data confirm that DBS most likely takes effect via network modulation.
KW  - nucleus
KW  - serotonin
KW  - schizophrenia
KW  - dopamine
KW  - double-blind
KW  - psychiatric disorders
KW  - in vivo
KW  - acoustic startle
KW  - reflex
KW  - modulation
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-138300
VL  - 5
IS  - e675
ER  - 
TY  - JOUR
A1  - Stepniak, Beata
A1  - Kästner, Anne
A1  - Poggi, Giulia
A1  - Mitjans, Marina
A1  - Begemann, Martin
A1  - Hartmann, Annette
A1  - Van der Auwera, Sandra
A1  - Sananbenesi, Farahnaz
A1  - Krüger-Burg, Dilja
A1  - Matuszko, Gabriela
A1  - Brosi, Cornelia
A1  - Homuth, Georg
A1  - Völzke, Henry
A1  - Benseler, Fritz
A1  - Bagni, Claudia
A1  - Fischer, Utz
A1  - Dityatev, Alexander
A1  - Grabe, Hans-Jörgen
A1  - Rujescu, Dan
A1  - Fischer, Andre
A1  - Ehrenreich, Hannelore
T1  - Accumulated common variants in the broader fragile X gene family modulate autistic phenotypes
JF  - EMBO Molecular Medicine
N2  - Fragile X syndrome (FXS) is mostly caused by a CGG triplet expansion in the fragile X mental retardation 1 gene (FMR1). Up to 60% of affected males fulfill criteria for autism spectrum disorder (ASD), making FXS the most frequent monogenetic cause of syndromic ASD. It is unknown, however, whether normal variants (independent of mutations) in the fragile X gene family (FMR1, FXR1, FXR2) and in FMR2 modulate autistic features. Here, we report an accumulation model of 8 SNPs in these genes, associated with autistic traits in a discovery sample of male patients with schizophrenia (N = 692) and three independent replicate samples: patients with schizophrenia (N = 626), patients with other psychiatric diagnoses (N = 111) and a general population sample (N = 2005). For first mechanistic insight, we contrasted microRNA expression in peripheral blood mononuclear cells of selected extreme group subjects with high-versus low-risk constellation regarding the accumulation model. Thereby, the brain-expressed miR-181 species emerged as potential "umbrella regulator", with several seed matches across the fragile X gene family and FMR2. To conclude, normal variation in these genes contributes to the continuum of autistic phenotypes.
KW  - permutation
KW  - miR-181
KW  - PGAS
KW  - FXR2
KW  - FXR1
KW  - FMR2
KW  - FMR1
KW  - identification
KW  - protein
KW  - fraxe mental retardation
KW  - CGG repeat
KW  - CPG Island
KW  - schizophrenia
KW  - expression
KW  - males
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-136893
VL  - 7
IS  - 12
ER  -