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1.
Schizophr Bull ; 49(4): 1055-1066, 2023 07 04.
Article in English | MEDLINE | ID: mdl-37021666

ABSTRACT

BACKGROUND: There is limited knowledge of whether cognitive-behavioral therapy (CBT) or second-generation antipsychotics (SGAs) should be recommended as the first-line treatment in individuals at clinical high risk for psychosis (CHRp). HYPOTHESIS: To examine whether individual treatment arms are superior to placebo and whether CBT is non-inferior to SGAs in preventing psychosis over 12 months of treatment. STUDY DESIGN: PREVENT was a blinded, 3-armed, randomized controlled trial comparing CBT to clinical management plus aripiprazole (CM + ARI) or plus placebo (CM + PLC) at 11 CHRp services. The primary outcome was transition to psychosis at 12 months. Analyses were by intention-to-treat. STUDY RESULTS: Two hundred eighty CHRp individuals were randomized: 129 in CBT, 96 in CM + ARI, and 55 in CM + PLC. In week 52, 21 patients in CBT, 19 in CM + ARI, and 7 in CM + PLC had transitioned to psychosis, with no significant differences between treatment arms (P = .342). Psychopathology and psychosocial functioning levels improved in all treatment arms, with no significant differences. CONCLUSIONS: The analysis of the primary outcome transition to psychosis at 12 months and secondary outcomes symptoms and functioning did not demonstrate significant advantages of the active treatments over placebo. The conclusion is that within this trial, neither low-dose aripiprazole nor CBT offered additional benefits over clinical management and placebo.


Subject(s)
Antipsychotic Agents , Cognitive Behavioral Therapy , Psychotic Disorders , Humans , Aripiprazole/pharmacology , Aripiprazole/therapeutic use , Psychotic Disorders/drug therapy , Psychotic Disorders/prevention & control , Antipsychotic Agents/pharmacology , Antipsychotic Agents/therapeutic use , Knowledge , Treatment Outcome
2.
JCI Insight ; 8(7)2023 04 10.
Article in English | MEDLINE | ID: mdl-36821372

ABSTRACT

We examine whether calcineurin or protein phosphatase 2B (PP2B) regulates the basolateral inwardly rectifying potassium channel Kir4.1/Kir5.1 in the distal convoluted tubule (DCT). Application of tacrolimus (FK506) or cyclosporine A (CsA) increased whole-cell Kir4.1/Kir5.1-mediated K+ currents and hyperpolarized the DCT membrane. Moreover, FK506-induced stimulation of Kir4.1/Kir5.1 was absent in kidney tubule-specific 12 kDa FK506-binding protein-knockout mice (Ks-FKBP-12-KO). In contrast, CsA stimulated Kir4.1/Kir5.1 of the DCT in Ks-FKBP-12-KO mice, suggesting that FK506-induced stimulation of Kir4.1/Kir5.1 was due to inhibiting PP2B. Single-channel patch-clamp experiments demonstrated that FK506 or CsA stimulated the basolateral Kir4.1/Kir5.1 activity of the DCT, defined by NPo (a product of channel number and open probability). However, this effect was absent in the DCT treated with Src family protein tyrosine kinase (SFK) inhibitor or hydroxyl peroxide. Fluorescence imaging demonstrated that CsA treatment increased membrane staining intensity of Kir4.1 in the DCT of Kcnj10fl/fl mice. Moreover, CsA treatment had no obvious effect on phosphorylated NaCl cotransporter (pNCC) expression in Ks-Kir4.1-KO mice. Immunoblotting showed acute FK506 treatment increased pNCC expression in Kcnj10fl/fl mice, but this effect was attenuated in Ks-Kir4.1-KO mice. In vivo measurement of thiazide-induced renal Na+ excretion demonstrated that FK506 enhanced thiazide-induced natriuresis. This effect was absent in Ks-FKBP-12-KO mice and blunted in Ks-Kir4.1-KO mice. We conclude that inhibition of PP2B stimulates Kir4.1/Kir5.1 of the DCT and NCC and that PP2B inhibition-induced stimulation of NCC is partially achieved by stimulation of the basolateral Kir4.1/Kir5.1.


Subject(s)
Calcineurin Inhibitors , Sodium Chloride , Animals , Mice , Solute Carrier Family 12, Member 3/metabolism , Calcineurin Inhibitors/pharmacology , Sodium Chloride/metabolism , Tacrolimus/pharmacology , Tacrolimus Binding Protein 1A/metabolism , Mice, Knockout , Thiazides
3.
Eur Arch Psychiatry Clin Neurosci ; 269(8): 931-940, 2019 Dec.
Article in English | MEDLINE | ID: mdl-30539230

ABSTRACT

Obsessive-compulsive symptoms (OCS) in patients with schizophrenia are a common co-occurring condition, often associated with additional impairments. A subgroup of these patients develops OCS during treatment with second-generation antipsychotics (SGAs), most importantly clozapine and olanzapine. So far, little is known about possible neural mechanism of these SGAs, which seem to aggravate or induce OCS. To investigate the role of SGA treatment on neural activation and connectivity during emotional processing, patients were stratified according to their monotherapy into two groups (group I: clozapine or olanzapine, n = 20; group II: amisulpride or aripiprazole, n = 20). We used an fMRI approach, applying an implicit emotion recognition task. Group comparisons showed significantly higher frequency and severity of comorbid OCS in group I than group II. Task specific activation was attenuated in group I in the left amygdala. Furthermore, functional connectivity from left amygdala to right ventral striatum was reduced in group I. Reduced amygdala activation was associated with OCS severity. Recent literature suggests an involvement of an amygdala-cortico-striatal network in the pathogenesis of obsessive-compulsive disorder. The observed differential activation and connectivity pattern of the amygdala might thus indicate a neural mechanism for the development of SGA-associated OCS in patients with schizophrenia. Further neurobiological research and interventional studies are needed for causal inferences.


Subject(s)
Amygdala/drug effects , Antipsychotic Agents/therapeutic use , Clozapine/therapeutic use , Olanzapine/therapeutic use , Schizophrenia/drug therapy , Adult , Amygdala/diagnostic imaging , Amygdala/pathology , Amygdala/physiopathology , Carrier Proteins , Female , Functional Neuroimaging , Humans , Male , Neural Pathways/drug effects , Neural Pathways/pathology , Neural Pathways/physiopathology , Saccharomyces cerevisiae Proteins , Schizophrenia/diagnostic imaging , Schizophrenia/pathology , Schizophrenia/physiopathology
4.
Early Interv Psychiatry ; 12(2): 217-228, 2018 04.
Article in English | MEDLINE | ID: mdl-26801553

ABSTRACT

AIM: Functional disability and social consequences frequently occur at the prodromal stage of schizophrenia. Efforts to recognize an increasing risk of psychosis onset have thus become a topical issue worldwide. This is to introduce the English version of the ERIraos early-recognition inventory. METHODS: The ERIraos, developed in a systematic, empirical approach from the Instrument for the Retrospective Assessment of the Onset of Schizophrenia, incorporates basic symptoms from the Cologne Early Recognition Study. The research version also includes as further predictive items so-called brief limited intermittent psychotic symptoms and attenuated psychotic symptoms from the Comprehensive Assessment of At-Risk Mental States instrument. RESULTS: The ERIraos with its 15-item screening Checklist and 50-item Symptom List permits early recognition of psychosis risk in three steps of decreasing sensitivity and increasing specificity. Step 1 relies on patients' self-perception of symptoms, which prompt them to contact a primary health service. There, in Step 2, at-risk individuals are identified using the Checklist, characterized by a low-risk threshold, and referred to further examination using the Symptom List (Step 3). Information on symptom accumulation and increasing symptom severity enhances the instrument's predictive power. In a validation test, psychotic transitions increased linearly up to 50% over 2 years. Compared with other instruments and on the prodromal stage of depressive disorder, the ERIraos has shown good predictive capacity. CONCLUSIONS: The ERIraos has been successfully employed as a two-step tool for the early recognition of psychosis risk in several German studies and translated into several foreign languages.


Subject(s)
Early Diagnosis , Prodromal Symptoms , Psychiatric Status Rating Scales , Psychotic Disorders/diagnosis , Psychotic Disorders/psychology , Schizophrenia/diagnosis , Schizophrenic Psychology , Adolescent , Adult , Child , Female , Humans , Male , Middle Aged , Psychotic Disorders/complications , Retrospective Studies , Schizophrenia/complications , Sensitivity and Specificity , Translations , Young Adult
5.
Early Interv Psychiatry ; 12(4): 586-595, 2018 08.
Article in English | MEDLINE | ID: mdl-27169782

ABSTRACT

AIM: Patients with an increased risk for psychosis ('at-risk mental state' (ARMS)) present various neurocognitive deficits. Not least because of differences in identifying the ARMS, results of previous studies are inconsistent. In most studies ARMS-patients are classified by the experience of attenuated psychotic symptoms (APS) and/or brief limited intermittent psychotic symptoms (BLIPS). Few studies additionally assessed cognitive basic symptoms (BS). A comprehensive assessment in the very early stage of the ARMS is missing. METHODS: In the present study we characterized ARMS-patients for cognitive BS (ARMS-BS), APS and BLIPS (ARMS-A/B) according to the Early Recognition Inventory based on IRAOS (ERIraos). Furthermore, we assessed neurocognitive deficits using the MATRICS consensus cognitive battery for schizophrenia with a primary hypothesis regarding working memory performance. Groups of 38 ARMS-patients and 38 healthy controls were matched for age, gender, education and premorbid verbal intelligence. RESULTS: Between-group comparisons revealed significant poorer working memory performance in addition to lower verbal learning and problem solving, slower processing speed and lower global neurocognitive functioning in ARMS-patients as compared to controls. ARMS-BS did not differ from ARMS-A/B. CONCLUSIONS: These results underscore the presence of cognitive limitations in patients only presenting with cognitive BS. Knowledge of these early cognitive deviations supports the inclusion of early ARMS-stages into a comprehensive concept of the psychosis risk state. Therapeutic interventions already applied at this stage might prevent deterioration of constraints. Longitudinal and interventional studies investigating the interaction of cognitive BS and neurocognitive as well as metacognitive deficits are warranted.


Subject(s)
Cognitive Dysfunction/psychology , Psychotic Disorders/psychology , Adolescent , Adult , Case-Control Studies , Cognitive Dysfunction/complications , Cognitive Dysfunction/diagnosis , Early Diagnosis , Female , Humans , Male , Memory, Short-Term , Neuropsychological Tests , Prodromal Symptoms , Psychotic Disorders/complications , Psychotic Disorders/diagnosis , Verbal Learning , Young Adult
6.
Early Interv Psychiatry ; 12(6): 1157-1165, 2018 12.
Article in English | MEDLINE | ID: mdl-28524542

ABSTRACT

BACKGROUND: The objective of this study is to test the conflicting theories concerning the association of negative self and other schemata and paranoid ideation. METHODS: A risk-based approach, including risk stratification, is used to gain insight into the association of the negative self and other schemata that may be shared by individuals or differentiate between individuals at clinical high risk (CHR) for a first-episode psychosis and those with full-blown psychosis. The dataset includes a sample of individuals at CHR (n = 137) and a sample of individuals with persisting positive symptoms (PPS, n = 211). The CHR sample was subdivided according to a prognostic index yielding 4 CHR sub-classes with increasing risk for transition to psychosis. RESULTS: Negative beliefs about the self were associated with paranoid ideation in CHR and a lower risk state. In the highest risk state and full-blown psychosis, there is an association with negative beliefs about others. CONCLUSION: These findings are in line with theories suggesting a switch from a predominantly activated negative self-schema to a malevolent others-schema in association with paranoid ideation along the risk-continuum. However, due to methodological limitations these results should be replicated by future studies.


Subject(s)
Culture , Paranoid Disorders/diagnosis , Psychotic Disorders/diagnosis , Adult , Female , Humans , Male , Paranoid Disorders/complications , Prodromal Symptoms , Prognosis , Psychotic Disorders/complications , Young Adult
7.
Eur Arch Psychiatry Clin Neurosci ; 267(3): 213-224, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27565806

ABSTRACT

Several studies in patients with schizophrenia reported a marked reduction in sleep spindle activity. To investigate whether the reduction may be linked to genetic risk of the illness, we analysed sleep spindle activity in healthy volunteers, patients with schizophrenia and first-degree relatives, who share an enriched set of schizophrenia susceptibility genes. We further investigated the correlation of spindle activity with cognitive function in first-degree relatives and whether spindle abnormalities affect both fast (12-15 Hz) and slow (9-12 Hz) sleep spindles. We investigated fast and slow sleep spindle activity during non-rapid eye movement sleep in a total of 47 subjects comprising 17 patients with schizophrenia, 13 healthy first-degree relatives and 17 healthy volunteers. Groups were balanced for age, gender, years of education and estimated verbal IQ. A subsample of relatives received additional testing for memory performance. Compared to healthy volunteers, fast spindle density was reduced in patients with schizophrenia and healthy first-degree relatives following a pattern consistent with an assumed genetic load for schizophrenia. The deficit in spindle density was specific to fast spindles and was associated with decreased memory performance. Our findings indicate familial occurrence of this phenotype and thus support the hypothesis that deficient spindle activity relates to genetic liability for schizophrenia. Furthermore, spindle reductions predict impaired cognitive function and are specific to fast spindles. This physiological marker should be further investigated as an intermediate phenotype of schizophrenia. It could also constitute a target for drug development, especially with regard to cognitive dysfunction.


Subject(s)
Brain Waves/physiology , Cognition Disorders/etiology , Schizophrenia/complications , Schizophrenia/genetics , Sleep Wake Disorders/etiology , Adolescent , Adult , Analysis of Variance , Brain Waves/genetics , Electroencephalography , Family , Female , Humans , Male , Middle Aged , Neuropsychological Tests , Polysomnography , Psychiatric Status Rating Scales , Young Adult
8.
Eur Arch Psychiatry Clin Neurosci ; 267(7): 597-610, 2017 Oct.
Article in English | MEDLINE | ID: mdl-27770284

ABSTRACT

Schizophrenia is associated with significant impairments in social cognition. These impairments have been shown to go along with altered activation of the posterior superior temporal sulcus (pSTS). However, studies that investigate connectivity of pSTS during social cognition in schizophrenia are sparse. Twenty-two patients with schizophrenia and 22 matched healthy controls completed a social-cognitive task for functional magnetic resonance imaging that allows the investigation of affective Theory of Mind (ToM), emotion recognition and the processing of neutral facial expressions. Moreover, a resting-state measurement was taken. Patients with schizophrenia performed worse in the social-cognitive task (main effect of group). In addition, a group by social-cognitive processing interaction was revealed for activity, as well as for connectivity during the social-cognitive task, i.e., patients with schizophrenia showed hyperactivity of right pSTS during neutral face processing, but hypoactivity during emotion recognition and affective ToM. In addition, hypoconnectivity between right and left pSTS was revealed for affective ToM, but not for neutral face processing or emotion recognition. No group differences in connectivity from right to left pSTS occurred during resting state. This pattern of aberrant activity and connectivity of the right pSTS during social cognition might form the basis of false-positive perceptions of emotions and intentions and could contribute to the emergence and sustainment of delusions.


Subject(s)
Nerve Net/diagnostic imaging , Schizophrenia/pathology , Schizophrenic Psychology , Social Behavior , Temporal Lobe/diagnostic imaging , Adult , Brain Mapping , Cognition/physiology , Emotions , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged , Psychiatric Status Rating Scales , Schizophrenia/diagnostic imaging , Theory of Mind
9.
Proc Natl Acad Sci U S A ; 113(44): 12568-12573, 2016 11 01.
Article in English | MEDLINE | ID: mdl-27791105

ABSTRACT

Schizophrenia is increasingly recognized as a disorder of distributed neural dynamics, but the molecular and genetic contributions are poorly understood. Recent work highlights a role for altered N-methyl-d-aspartate (NMDA) receptor signaling and related impairments in the excitation-inhibitory balance and synchrony of large-scale neural networks. Here, we combined a pharmacological intervention with novel techniques from dynamic network neuroscience applied to functional magnetic resonance imaging (fMRI) to identify alterations in the dynamic reconfiguration of brain networks related to schizophrenia genetic risk and NMDA receptor hypofunction. We quantified "network flexibility," a measure of the dynamic reconfiguration of the community structure of time-variant brain networks during working memory performance. Comparing 28 patients with schizophrenia, 37 unaffected first-degree relatives, and 139 healthy controls, we detected significant differences in network flexibility [F(2,196) = 6.541, P = 0.002] in a pattern consistent with the assumed genetic risk load of the groups (highest for patients, intermediate for relatives, and lowest for controls). In an observer-blinded, placebo-controlled, randomized, cross-over pharmacological challenge study in 37 healthy controls, we further detected a significant increase in network flexibility as a result of NMDA receptor antagonism with 120 mg dextromethorphan [F(1,34) = 5.291, P = 0.028]. Our results identify a potential dynamic network intermediate phenotype related to the genetic liability for schizophrenia that manifests as altered reconfiguration of brain networks during working memory. The phenotype appears to be influenced by NMDA receptor antagonism, consistent with a critical role for glutamate in the temporal coordination of neural networks and the pathophysiology of schizophrenia.


Subject(s)
Brain/physiopathology , Nerve Net/physiopathology , Receptors, N-Methyl-D-Aspartate/physiology , Schizophrenia/physiopathology , Adolescent , Adult , Brain/drug effects , Brain/metabolism , Brain Mapping , Dextromethorphan/therapeutic use , Excitatory Amino Acid Antagonists/therapeutic use , Female , Humans , Magnetic Resonance Imaging/methods , Male , Memory, Short-Term/drug effects , Memory, Short-Term/physiology , Nerve Net/drug effects , Nerve Net/metabolism , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Receptors, N-Methyl-D-Aspartate/genetics , Schizophrenia/genetics , Young Adult
10.
Psychiatry Res ; 238: 242-250, 2016 Apr 30.
Article in English | MEDLINE | ID: mdl-27086240

ABSTRACT

Prior studies have confirmed a bias against disconfirmatory evidence (BADE) in schizophrenia which has been associated with delusions. However, its role in the pathogenesis of psychosis is yet unclear. The objective was to investigate BADE for the first time in subjects with an at-risk-mental-state for psychosis (ARMS), patients with a first episode of psychosis without antipsychotic treatment (FEP) and healthy controls (HC). A standard BADE test presenting written scenarios was employed. In addition, psychometric rating scales and a neuropsychological test battery were applied. A three-staged image was revealed. FEP-patients showed a significant BADE compared to the other groups. The performance of ARMS-patients lay in between HC and FEP-patients. A trend towards significance became evident for a bias against confirmatory evidence (BACE) in FEP-patients. Results were not attributable to antipsychotic or other medication or depressive symptoms. Correlations with delusions reached medium effect sizes but failed significance after Bonferroni-corrections. These results provide evidence for aberrations in evidence integration in the pathogenesis of psychosis and contribute to our knowledge of metacognitive functioning which can be used for (meta-)cognitive intervention in psychosis.


Subject(s)
Cognition Disorders/diagnosis , Cognition Disorders/epidemiology , Psychotic Disorders/diagnosis , Psychotic Disorders/epidemiology , Schizophrenia/diagnosis , Schizophrenia/epidemiology , Adolescent , Adult , Antipsychotic Agents/therapeutic use , Bias , Cognition Disorders/drug therapy , Depression/diagnosis , Depression/drug therapy , Depression/epidemiology , Female , Humans , Male , Neuropsychological Tests , Psychometrics , Psychotic Disorders/drug therapy , Risk Factors , Schizophrenia/drug therapy , Young Adult
11.
J Psychiatry Neurosci ; 40(3): 163-73, 2015 May.
Article in English | MEDLINE | ID: mdl-25622039

ABSTRACT

BACKGROUND: Patients with schizophrenia display metacognitive impairments, such as hasty decision-making during probabilistic reasoning - the "jumping to conclusion" bias (JTC). Our recent fMRI study revealed reduced activations in the right ventral striatum (VS) and the ventral tegmental area (VTA) to be associated with decision-making in patients with schizophrenia. It is unclear whether these functional alterations occur in the at-risk mental state (ARMS). METHODS: We administered the classical beads task and fMRI among ARMS patients and healthy controls matched for age, sex, education and premorbid verbal intelligence. None of the ARMS patients was treated with antipsychotics. Both tasks request probabilistic decisions after a variable amount of stimuli. We evaluated activation during decision-making under certainty versus uncertainty and the process of final decision-making. RESULTS: We included 24 AMRS patients and 24 controls in our study. Compared with controls, ARMS patients tended to draw fewer beads and showed significantly more JTC bias in the classical beads task, mirroring findings in patients with schizophrenia. During fMRI, ARMS patients did not demonstrate JTC bias on the behavioural level, but showed a significant hypoactivation in the right VS during the decision stage. LIMITATIONS: Owing to the cross-sectional design of the study, results are constrained to a better insight into the neurobiology of risk constellations, but not prepsychotic stages. Nine of the ARMS patients were treated with antidepressants and/or lorazepam. CONCLUSION: As in patients with schizophrenia, a striatal hypoactivation was found in ARMS patients. Confounding effects of antipsychotic medication can be excluded. Our findings indicate that error prediction signalling and reward anticipation may be linked to striatal dysfunction during prodromal stages and should be examined for their utility in predicting transition risk.


Subject(s)
Decision Making/physiology , Schizophrenia/physiopathology , Ventral Striatum/physiopathology , Antidepressive Agents/therapeutic use , Brain Mapping , Cross-Sectional Studies , Female , Humans , Hypnotics and Sedatives/therapeutic use , Lorazepam/therapeutic use , Magnetic Resonance Imaging , Male , Neuropsychological Tests , Probability , Prodromal Symptoms , Risk , Schizophrenia/drug therapy , Schizophrenic Psychology , Ventral Striatum/drug effects , Young Adult
12.
Cancer Chemother Pharmacol ; 75(4): 691-700, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25618416

ABSTRACT

PURPOSE: New (4-aryl-1-methylimidazol-5-yl)cinnamoylhydroxamic acids were prepared as potential dual mode anticancer agents combining the antivascular effect of the 4,5-diarylimidazole moiety and the histone deacetylases (HDAC) inhibition by the cinnamoyl hydroxamate. METHODS: Their antiproliferative activity against a panel of primary cells and cancer cell lines was determined by MTT assays and their apoptosis induction by caspase-3 activation. Their ability to reduce the activity of HDAC was measured by enzymatic assays and Western blot analyses of cellular HDAC substrates. Additional effects on cancer cell migration were ascertained via immunofluorescence staining of cytoskeleton components and three-dimensional migration assays. The chorioallantoic membrane assay was used as an in vivo model to assess their antiangiogenic properties. RESULTS: The 4-phenyl- and 4-(p-methoxyphenyl)-imidazole derivatives had a greater antiproliferative and apoptosis inducing effect in a variety of cancer cell lines when compared with the approved HDAC inhibitor SAHA, and most distinctly so in non-malignant human umbilical vein endothelial cells. Like SAHA, both compounds acted as pan-HDAC inhibitors. In 518A2 melanoma cells, they led to hyperacetylation of histones and of the cytoplasmic HDAC6 substrate alpha-tubulin. As a consequence, they inhibited the migration and invasion of these cells in transwell invasion assays. In keeping with its pronounced impact on endothelial cells, the 4-phenyl-imidazole derivative also inhibited the growth and sprouting of blood vessels in the chorioallantoic membrane of fertilized hen eggs. CONCLUSIONS: The 4-phenyl- and 4-(p-methoxyphenyl)-imidazole compounds combine the antivascular effects of 4,5-diarylimidazoles with HDAC inhibition by cinnamoyl hydroxamates and show additional antimetastatic activity. They are promising candidates for pleiotropic HDAC inhibitors.


Subject(s)
Antineoplastic Agents/pharmacology , Histone Deacetylase Inhibitors/pharmacology , Hydroxamic Acids/pharmacology , Imidazoles/pharmacology , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Apoptosis , Cell Line, Tumor , Cell Proliferation/drug effects , Chick Embryo , Chorioallantoic Membrane/blood supply , Chorioallantoic Membrane/drug effects , Histone Deacetylase Inhibitors/chemical synthesis , Histone Deacetylase Inhibitors/chemistry , Humans , Hydroxamic Acids/chemical synthesis , Hydroxamic Acids/chemistry , Imidazoles/chemical synthesis , Imidazoles/chemistry , Molecular Structure , Neovascularization, Physiologic/drug effects , Structure-Activity Relationship
13.
J Psychiatry Neurosci ; 40(2): 89-99, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25268790

ABSTRACT

BACKGROUND: Patients with schizophrenia have an approximately 10-fold higher risk for obsessive-compulsive symptoms (OCS) than the general population. A large subgroup seems to experience OCS as a consequence of second-generation antipsychotic agents (SGA), such as clozapine. So far little is known about underlying neural mechanisms. METHODS: To investigate the role of SGA treatment on neural processing related to OCS in patients with schizophrenia, we stratified patients according to their monotherapy into 2 groups (group I: clozapine or olanzapine; group II: amisulpride or aripiprazole). We used an fMRI approach, applying a go/no-go task assessing inhibitory control and an n-back task measuring working memory. RESULTS: We enrolled 21 patients in group I and 19 patients in group II. Groups did not differ regarding age, sex, education or severity of psychotic symptoms. Frequency and severity of OCS were significantly higher in group I and were associated with pronounced deficits in specific cognitive abilities. Whereas brain activation patterns did not differ during working memory, group I showed significantly increased activation in the orbitofrontal cortex (OFC) during response inhibition. Alterations in OFC activation were associated with the severity of obsessions and mediated the association between SGA treatment and co-occurring OCS on a trend level. LIMITATIONS: The main limitation of this study is its cross-sectional design. CONCLUSION: To our knowledge, this is the first imaging study conducted to elucidate SGA effects on neural systems related to OCS. We propose that alterations in brain functioning reflect a pathogenic mechanism in the development of SGA-induced OCS in patients with schizophrenia. Longitudinal studies and randomized interventions are needed to prove the suggested causal interrelations.


Subject(s)
Antipsychotic Agents/therapeutic use , Prefrontal Cortex/drug effects , Prefrontal Cortex/physiopathology , Schizophrenia/drug therapy , Schizophrenia/physiopathology , Adult , Amisulpride , Aripiprazole , Benzodiazepines/therapeutic use , Brain Mapping , Clozapine/therapeutic use , Executive Function/drug effects , Executive Function/physiology , Female , Humans , Inhibition, Psychological , Magnetic Resonance Imaging , Male , Neuropsychological Tests , Obsessive Behavior/drug therapy , Obsessive Behavior/physiopathology , Olanzapine , Piperazines/therapeutic use , Psychiatric Status Rating Scales , Psychomotor Performance/drug effects , Psychomotor Performance/physiology , Quinolones/therapeutic use , Sulpiride/analogs & derivatives , Sulpiride/therapeutic use
14.
Psychiatry Res ; 225(3): 596-603, 2015 Feb 28.
Article in English | MEDLINE | ID: mdl-25530415

ABSTRACT

Prior studies with schizophrenia patients described a reduced ability to discriminate between correct and false memories in terms of confidence compared to control groups. This metamemory bias has been associated with the emergence and maintenance of delusions. The relation to neuropsychological performance and other clinical dimensions is incompletely understood. In a cross-sectional study, metamemory functioning was explored in 32 schizophrenia patients and 25 healthy controls. Metamemory was assessed using a verbal recognition task combined with retrospective confidence level ratings. Associations of metamemory performance with six neuropsychological domains (executive functioning/problem solving, speed of processing, working memory, verbal and visual learning, and attention/vigilance) and psychopathological measures were analyzed. Results revealed a significantly smaller discrepancy between confidence ratings for correct and incorrect recognitions in the patient group. Furthermore, patients showed significantly lower recognition accuracy in the metamemory task and marked deficits in all neuropsychological domains. Across all participants, metamemory performance significantly correlated with executive functioning and working memory. No associations with delusions were found. This data confirms prior findings of metamemory biases in schizophrenia. Selective neuropsychological abilities seem to be modulating factors of metamemory functioning. Longitudinal studies in at risk mental state and first-episode patients are needed to reveal causal interrelations.


Subject(s)
Attention , Cognition Disorders/physiopathology , Executive Function , Memory Disorders/physiopathology , Memory, Short-Term , Problem Solving , Schizophrenia/physiopathology , Schizophrenic Psychology , Adult , Case-Control Studies , Cognition Disorders/etiology , Cognition Disorders/psychology , Cross-Sectional Studies , Delusions/psychology , Emotions , Female , Humans , Male , Memory Disorders/etiology , Memory Disorders/psychology , Middle Aged , Neuropsychological Tests , Schizophrenia/complications
15.
Psychiatry Res ; 219(1): 72-8, 2014 Sep 30.
Article in English | MEDLINE | ID: mdl-24880580

ABSTRACT

Previous studies have demonstrated a cognitive bias in the integration of disconfirmatory evidence (BADE) in patients with schizophrenia. This bias has been associated with delusions. So far, it is unclear how the integration of evidence is associated with neurocognitive capabilities. In the current study, 31 patients with schizophrenia and 29 healthy controls, matched on age, gender, education and premorbid verbal intelligence, underwent a BADE task. Written scenarios of three consecutive sentences each were presented, which progressively reduced the ambiguity of situations. Participants were asked to rate the plausibility of four possible interpretations and adjust their ratings in response to the provided sentences. Psychometric rating scales and a neuropsychological test battery were applied. Patients displayed a bias in the integration of confirmatory, but not disconfirmatory evidence and a liberal acceptance of belief formation. Correlation analyses revealed no associations of evidence integration with the severity of positive symptoms, but with neurocognitive domains, especially with processing speed, executive functioning, vigilance and working memory. In conclusion, patients with schizophrenia show a bias in evidence integration. Neurocognitive functioning emerged as a modulatory factor that should be considered in further research. Studies investigating BADE in earlier stages of psychosis will be necessary to reveal causal relationships.


Subject(s)
Attention , Culture , Delusions/diagnosis , Neuropsychological Tests/statistics & numerical data , Schizophrenia/diagnosis , Schizophrenic Psychology , Adult , Case-Control Studies , Decision Making , Delusions/psychology , Executive Function , Factor Analysis, Statistical , Female , Humans , Intelligence , Male , Middle Aged , Psychometrics
16.
Schizophr Res ; 156(2-3): 143-9, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24831391

ABSTRACT

Patients with schizophrenia suffer from deficits in monitoring and controlling their own thoughts. Within these so-called metacognitive impairments, alterations in probabilistic reasoning might be one cognitive phenomenon disposing to delusions. However, so far little is known about alterations in associated brain functionality. A previously established task for functional magnetic resonance imaging (fMRI), which requires a probabilistic decision after a variable amount of stimuli, was applied to 23 schizophrenia patients and 28 healthy controls matched for age, gender and educational levels. We compared activation patterns during decision-making under conditions of certainty versus uncertainty and evaluated the process of final decision-making in ventral striatum (VS) and ventral tegmental area (VTA). We replicated a pre-described extended cortical activation pattern during probabilistic reasoning. During final decision-making, activations in several fronto- and parietocortical areas, as well as in VS and VTA became apparent. In both of these regions schizophrenia patients showed a significantly reduced activation. These results further define the network underlying probabilistic decision-making. The observed hypo-activation in regions commonly associated with dopaminergic neurotransmission fits into current concepts of disrupted prediction error signaling in schizophrenia and suggests functional links to reward anticipation. Forthcoming studies with patients at risk for psychosis and drug-naive first episode patients are necessary to elucidate the development of these findings over time and the interplay with associated clinical symptoms.


Subject(s)
Decision Making/physiology , Probability , Schizophrenia/physiopathology , Ventral Striatum/physiopathology , Ventral Tegmental Area/physiopathology , Adult , Brain/physiopathology , Brain Mapping , Female , Humans , Magnetic Resonance Imaging , Male , Neural Pathways/physiopathology , Neuropsychological Tests , Psychometrics , Schizophrenic Psychology , Thinking/physiology , Uncertainty
17.
Compr Psychiatry ; 54(7): 1068-76, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23759152

ABSTRACT

The identification of patients carrying an increased risk of psychosis is one of the most important demands in schizophrenia research. Currently used diagnostic instruments mainly focus on either attenuated psychotic symptoms and brief limited intermittent psychotic symptoms or solely cognitive basic symptoms. The "Early Recognition Inventory based on IRAOS" (ERIraos) has been developed as a comprehensive assessment of both symptom groups within one scale. We compared the results obtained by ERIraos with an international standard instrument, the "Comprehensive Assessment of At Risk Mental States" (CAARMS) and applied both scales in a sample of 121 outpatients positively tested on a screening checklist for at risk mental states (ARMS). Subsamples were classified as first episode of psychosis, late ARMS with prevalent attenuated psychotic symptoms and/or brief limited intermittent psychotic symptoms, earlier stages of ARMS presenting cognitive basic symptoms as well as a vulnerability group, also differing regarding mean age and psychosocial functioning. Our results point to a higher sensitivity of ERIraos compared to scales that mainly focus on attenuated psychotic symptoms and brief limited intermittent psychotic symptoms. A detailed assessment of cognitive basic symptoms seems to be important in early detection, might be an important focus for therapeutic interventions in ARMS patients and might sustain attempts to alleviate cognitive dysfunction in schizophrenia.


Subject(s)
Cognition , Psychotic Disorders/diagnosis , Schizophrenia/diagnosis , Adult , Age Factors , Early Diagnosis , Female , Humans , Male , Personality Inventory , Psychiatric Status Rating Scales , Psychotic Disorders/psychology , Risk Assessment , Risk Factors , Schizophrenic Psychology , Sensitivity and Specificity
18.
Schizophr Bull ; 39(6): 1261-71, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23104864

ABSTRACT

BACKGROUND: Amongst schizophrenia patients, a large subgroup of up to 25% also suffers from comorbid obsessive-compulsive symptoms (OCSs). The association between comorbid OCSs in these patients and neuropsychological impairment remains unclear and somewhat contradictory. Longitudinal approaches investigating the stability of OCS-associated cognitive deficits are missing. METHODS: Thirty-seven patients with schizophrenia and comorbid OCSs and 43 schizophrenia patients without OCS were assessed with a comprehensive cognitive test battery and compared at baseline and, again, 12 months later. RESULTS: Schizophrenia patients with comorbid OCSs showed significant pronounced deficits, with increasing effect sizes over the 12-month assessment period in specific cognitive areas such as visuospatial perception and visual memory (WAIS-R block design, Rey-Osterrieth Complex Figure Test), executive functioning (perseveration in the Wisconsin Card Sorting test), and cognitive flexibility (Trail Making test B). These cognitive domains are correlated with OCS severity and are known to be candidate cognitive domains in obsessive-compulsive disorder (OCD). CONCLUSIONS: OCSs in schizophrenia is associated with specific and longitudinally stable cognitive deficits, strongly arguing for at least partially overlapping neurobiological mechanisms with OCD. Prospective studies involving patients with at-risk mental states for psychosis are necessary to decipher the interaction of cognitive impairment and the clinical manifestations of schizophrenia and OCSs. This might facilitate the definition of patients at high risk for OCSs, an early detection of subclinical levels, therapeutic interventions, and clinical monitoring.


Subject(s)
Cognition Disorders/diagnosis , Obsessive-Compulsive Disorder/physiopathology , Schizophrenia/physiopathology , Adult , Cognition Disorders/epidemiology , Comorbidity , Female , Humans , Longitudinal Studies , Male , Middle Aged , Neuropsychological Tests , Obsessive-Compulsive Disorder/epidemiology , Schizophrenia/epidemiology , Severity of Illness Index
19.
J Psychopharmacol ; 27(4): 349-57, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23095245

ABSTRACT

Indirect evidence supports the assumption that antiserotonergic second-generation antipsychotics (SGA) induce and aggravate obsessive-compulsive symptoms (OCS) in schizophrenia. However, multimodal studies assessing the long-term interaction of pharmacotherapy and psychopathology are missing. Over 12 months, we followed-up 75 schizophrenia patients who were classified into two groups according to antipsychotic treatment: clozapine or olanzapine (group I) versus aripiprazole or amisulpride (group II). We applied the Yale Brown Obsessive Compulsive Scale (YBOCS) and investigated between-group changes over time as the primary endpoint. Group I showed markedly higher YBOCS scores at both time points. Repeated measure analyses of variance (ANOVAs) revealed significant interaction effects of group and time (per protocol sample (PP): p=0.006). This was due to persistently high OCS severity within group I, and decreasing YBOCS scores within group II. OCS severity correlated significantly with the negative and general psychopathology subscales of the Positive and Negative Syndrome Scale (PANSS), as well as with depressive symptoms. The progressive differences in OCS severity between our groups support the assumption of differential pharmacodynamic effects on comorbid OCS in schizophrenia. Further studies should address the pathogenetic mechanism, define patients at risk and facilitate early detection as well as therapeutic interventions.


Subject(s)
Antipsychotic Agents/adverse effects , Dopamine Antagonists/adverse effects , Obsessive Behavior/chemically induced , Schizophrenia/drug therapy , Selective Serotonin Reuptake Inhibitors/adverse effects , Serotonin Antagonists/adverse effects , Adult , Antipsychotic Agents/therapeutic use , Comorbidity , Depression/chemically induced , Depression/epidemiology , Depression/prevention & control , Diagnostic and Statistical Manual of Mental Disorders , Dopamine Antagonists/therapeutic use , Female , Humans , Longitudinal Studies , Male , Middle Aged , Obsessive Behavior/epidemiology , Obsessive Behavior/prevention & control , Patient Dropouts , Prospective Studies , Psychiatric Status Rating Scales , Schizophrenia/epidemiology , Serotonin Antagonists/therapeutic use , Selective Serotonin Reuptake Inhibitors/therapeutic use
20.
Schizophr Res ; 140(1-3): 114-21, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22784688

ABSTRACT

Patients with schizophrenia show deficits in motivation, reward anticipation and salience attribution. Several functional magnetic resonance imaging (fMRI) investigations revealed neurobiological correlates of these deficits, raising the hypothesis of a common basis in midbrain dopaminergic signaling. However, investigations of drug-naïve first-episode patients with comprehensive fMRI tasks are still missing. We recruited unmedicated schizophrenia spectrum patients (N=27) and healthy control subjects (N=27) matched for sex, age and educational levels. An established monetary reward anticipation task in combination with a novel task aiming at implicit salience attribution without the confound of monetary incentive was applied. Patients showed reduced right ventral striatal activation during reward anticipation. Furthermore, patients with a more pronounced hypoactivation attributed more salience to neutral stimuli, had more positive symptoms and better executive functioning. In the patient group, a more differentially active striatum during reward anticipation was correlated positively to differential ventral striatal activation in the implicit salience attribution task. In conclusion, a deficit in ventral striatal activation during reward anticipation can already be seen in drug-naïve, first episode schizophrenia patients. The data suggest that rather a deficit in differential ventral striatal activation than a generally reduced activation underlies motivational deficits in schizophrenia and that this deficit is related to the aberrant salience attribution.


Subject(s)
Basal Ganglia/physiopathology , Motivation , Reward , Schizophrenia/pathology , Schizophrenia/physiopathology , Statistics as Topic , Adult , Analysis of Variance , Basal Ganglia/blood supply , Female , Functional Laterality , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Neuropsychological Tests , Oxygen/blood , Photic Stimulation , Reaction Time/physiology , Recognition, Psychology , Young Adult
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