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1.
Am J Psychiatry ; : appiajp201919060583, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32046535

RESUMO

OBJECTIVE: 22q11.2 deletion syndrome (22q11DS) is among the strongest known genetic risk factors for schizophrenia. Previous studies have reported variable alterations in subcortical brain structures in 22q11DS. To better characterize subcortical alterations in 22q11DS, including modulating effects of clinical and genetic heterogeneity, the authors studied a large multicenter neuroimaging cohort from the ENIGMA 22q11.2 Deletion Syndrome Working Group. METHODS: Subcortical structures were measured using harmonized protocols for gross volume and subcortical shape morphometry in 533 individuals with 22q11DS and 330 matched healthy control subjects (age range, 6-56 years; 49% female). RESULTS: Compared with the control group, the 22q11DS group showed lower intracranial volume (ICV) and thalamus, putamen, hippocampus, and amygdala volumes and greater lateral ventricle, caudate, and accumbens volumes (Cohen's d values, -0.90 to 0.93). Shape analysis revealed complex differences in the 22q11DS group across all structures. The larger A-D deletion was associated with more extensive shape alterations compared with the smaller A-B deletion. Participants with 22q11DS with psychosis showed lower ICV and hippocampus, amygdala, and thalamus volumes (Cohen's d values, -0.91 to 0.53) compared with participants with 22q11DS without psychosis. Shape analysis revealed lower thickness and surface area across subregions of these structures. Compared with subcortical findings from other neuropsychiatric disorders studied by the ENIGMA consortium, significant convergence was observed between participants with 22q11DS with psychosis and participants with schizophrenia, bipolar disorder, major depressive disorder, and obsessive-compulsive disorder. CONCLUSIONS: In the largest neuroimaging study of 22q11DS to date, the authors found widespread alterations to subcortical brain structures, which were affected by deletion size and psychotic illness. Findings indicate significant overlap between 22q11DS-associated psychosis, idiopathic schizophrenia, and other severe neuropsychiatric illnesses.

2.
World J Biol Psychiatry ; : 1-13, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32081071

RESUMO

Objectives: Biological strategies to improve treatment efficacy in clozapine-treated patients are urgently needed. Repetitive transcranial magnetic stimulation (rTMS) merits consideration as intervention for patients with persistent auditory hallucinations (AH) or negative symptoms (NS) not responding sufficiently to clozapine treatment.Methods: Data from 10 international RCTs of rTMS for patients being treated with clozapine were pooled. Two levels of symptomatic response were defined: improvement of ≥20% and ≥50% on study-specific primary endpoint scales. Changes in the positive and negative syndrome scale (PANSS) from baseline to endpoint assessment were also analysed.Results: Analyses of 131 patients did not reveal a significant difference for ≥20% and ≥50% response thresholds for improvement of AH, negative or total symptoms between active and sham rTMS groups. The number needed to treat (NNT) for an improvement in persistent AH was nine following active rTMS. PANSS scores did not improve significantly from baseline to endpoint between active and sham groups in studies investigating NS and AH.Conclusions: rTMS as a treatment for persistent symptoms in clozapine-treated patients did not show a beneficial effect of active compared to sham treatment. For AH, the size of the NNTs indicates a possible beneficial effect of rTMS.

3.
Mol Psychiatry ; 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358905

RESUMO

22q11.2 deletion syndrome (22q11DS)-a neurodevelopmental condition caused by a hemizygous deletion on chromosome 22-is associated with an elevated risk of psychosis and other developmental brain disorders. Prior single-site diffusion magnetic resonance imaging (dMRI) studies have reported altered white matter (WM) microstructure in 22q11DS, but small samples and variable methods have led to contradictory results. Here we present the largest study ever conducted of dMRI-derived measures of WM microstructure in 22q11DS (334 22q11.2 deletion carriers and 260 healthy age- and sex-matched controls; age range 6-52 years). Using harmonization protocols developed by the ENIGMA-DTI working group, we identified widespread reductions in mean, axial and radial diffusivities in 22q11DS, most pronounced in regions with major cortico-cortical and cortico-thalamic fibers: the corona radiata, corpus callosum, superior longitudinal fasciculus, posterior thalamic radiations, and sagittal stratum (Cohen's d's ranging from -0.9 to -1.3). Only the posterior limb of the internal capsule (IC), comprised primarily of corticofugal fibers, showed higher axial diffusivity in 22q11DS. 22q11DS patients showed higher mean fractional anisotropy (FA) in callosal and projection fibers (IC and corona radiata) relative to controls, but lower FA than controls in regions with predominantly association fibers. Psychotic illness in 22q11DS was associated with more substantial diffusivity reductions in multiple regions. Overall, these findings indicate large effects of the 22q11.2 deletion on WM microstructure, especially in major cortico-cortical connections. Taken together with findings from animal models, this pattern of abnormalities may reflect disrupted neurogenesis of projection neurons in outer cortical layers.

4.
Mol Psychiatry ; 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29895892

RESUMO

The 22q11.2 deletion (22q11DS) is a common chromosomal microdeletion and a potent risk factor for psychotic illness. Prior studies reported widespread cortical changes in 22q11DS, but were generally underpowered to characterize neuroanatomic abnormalities associated with psychosis in 22q11DS, and/or neuroanatomic effects of variability in deletion size. To address these issues, we developed the ENIGMA (Enhancing Neuro Imaging Genetics Through Meta-Analysis) 22q11.2 Working Group, representing the largest analysis of brain structural alterations in 22q11DS to date. The imaging data were collected from 10 centers worldwide, including 474 subjects with 22q11DS (age = 18.2 ± 8.6; 46.9% female) and 315 typically developing, matched controls (age = 18.0 ± 9.2; 45.9% female). Compared to controls, 22q11DS individuals showed thicker cortical gray matter overall (left/right hemispheres: Cohen's d = 0.61/0.65), but focal thickness reduction in temporal and cingulate cortex. Cortical surface area (SA), however, showed pervasive reductions in 22q11DS (left/right hemispheres: d = -1.01/-1.02). 22q11DS cases vs. controls were classified with 93.8% accuracy based on these neuroanatomic patterns. Comparison of 22q11DS-psychosis to idiopathic schizophrenia (ENIGMA-Schizophrenia Working Group) revealed significant convergence of affected brain regions, particularly in fronto-temporal cortex. Finally, cortical SA was significantly greater in 22q11DS cases with smaller 1.5 Mb deletions, relative to those with typical 3 Mb deletions. We found a robust neuroanatomic signature of 22q11DS, and the first evidence that deletion size impacts brain structure. Psychotic illness in this highly penetrant deletion was associated with similar neuroanatomic abnormalities to idiopathic schizophrenia. These consistent cross-site findings highlight the homogeneity of this single genetic etiology, and support the suitability of 22q11DS as a biological model of schizophrenia.

5.
Schizophr Res ; 201: 329-336, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29934249

RESUMO

OBJECTIVE: Transcranial direct current stimulation (tDCS) could be a treatment option for medication-resistant auditory hallucinations (AH), but so far results have been inconclusive, and large sample trials have been missing. This study used tDCS as a treatment method for these hallucinations in a double-blind, placebo-controlled study with a relatively large sample size. METHODS: Fifty-four patients of several diagnostic categories with medication-resistant AH were randomized and treated during 10 sessions of 20 min each, with either 2 mA tDCS or placebo, administered on five consecutive days (i.e., two sessions per day). Anodal stimulation was targeted at the left dorsolateral prefrontal cortex, cathodal stimulation at the left temporoparietal junction. AH severity was assessed using the Auditory Hallucination Rating Scale (AHRS). Other outcome measures were assessed with the Positive and Negative Syndrome Scale (PANSS), the Stroop, and the Trail Making Test. RESULTS: AH frequency and severity decreased significantly over time, as did the scores on the total and general subscales of the PANSS. However, there was no significant interaction effect with the treatment group on any of the main outcome measures. CONCLUSIONS: We found no evidence that tDCS is more effective for medication-resistant AH than placebo, even though AH frequency and severity decreased in both groups. An alternative strategy may be to offer tDCS at an earlier stage of illness. In the light of recent investigations into the neurophysiological mechanisms behind tDCS, we may also have to consider the possibility that tDCS is not able to induce any long-lasting brain changes.


Assuntos
Alucinações/terapia , Estimulação Transcraniana por Corrente Contínua , Adulto , Transtornos Psicóticos Afetivos/terapia , Idoso , Transtorno da Personalidade Borderline/terapia , Cognição , Método Duplo-Cego , Resistência a Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Desistentes do Tratamento , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/terapia , Esquizofrenia/terapia , Estimulação Transcraniana por Corrente Contínua/efeitos adversos , Falha de Tratamento , Adulto Jovem
6.
Psychol Med ; 48(10): 1655-1663, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29143717

RESUMO

BACKGROUND: Decline in cognitive functioning precedes the first psychotic episode in the course of schizophrenia and is considered a hallmark symptom of the disorder. Given the low incidence of schizophrenia, it remains a challenge to investigate whether cognitive decline coincides with disease-related changes in brain structure, such as white matter abnormalities. The 22q11.2 deletion syndrome (22q11DS) is an appealing model in this context, as 25% of patients develop psychosis. Furthermore, we recently showed that cognitive decline also precedes the onset of psychosis in individuals with 22q11DS. Here, we investigate whether the early cognitive decline in patients with 22q11DS is associated with alterations in white matter microstructure. METHODS: We compared the fractional anisotropy (FA) of white matter in 22q11DS patients with cognitive decline [n = 16; -18.34 (15.8) VIQ percentile points over 6.80 (2.39) years] to 22q11DS patients without cognitive decline [n = 18; 17.71 (20.17) VIQ percentile points over 5.27 (2.03) years] by applying an atlas-based approach to diffusion-weighted imaging data. RESULTS: FA was significantly increased (p < 0.05, FDR) in 22q11DS patients with a cognitive decline in the bilateral superior longitudinal fasciculus, the bilateral cingulum bundle, all subcomponents of the left internal capsule and the left superior frontal-occipital fasciculus as compared with 22q11DS patients without cognitive decline. CONCLUSIONS: Within 22q11DS, the early cognitive decline is associated with microstructural differences in white matter. At the mean age of 17.8 years, these changes are reflected in increased FA in several tracts. We hypothesize that similar brain alterations associated with cognitive decline take place early in the trajectory of schizophrenia.


Assuntos
Disfunção Cognitiva , Síndrome de DiGeorge , Transtornos Psicóticos , Substância Branca/patologia , Adolescente , Adulto , Criança , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Estudos de Coortes , Síndrome de DiGeorge/complicações , Síndrome de DiGeorge/diagnóstico por imagem , Síndrome de DiGeorge/patologia , Síndrome de DiGeorge/fisiopatologia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/etiologia , Transtornos Psicóticos/patologia , Transtornos Psicóticos/fisiopatologia , Substância Branca/diagnóstico por imagem , Adulto Jovem
9.
Schizophr Bull ; 42(1): 250-7, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26221051

RESUMO

BACKGROUND: Auditory verbal hallucinations (AVH) in schizophrenia are resistant to antipsychotic medication in approximately 25% of patients. Treatment with repetitive transcranial magnetic stimulation (rTMS) for refractory AVH has shown varying results. A stimulation protocol using continuous theta burst rTMS (TB-rTMS) showed high efficacy in open label studies. We tested TB-rTMS as a treatment strategy for refractory AVH in a double-blind, placebo-controlled trial. METHODS: Seventy-one patients with AVH were randomly allocated to TB-rTMS or placebo treatment. They received 10 TB-rTMS or sham treatments over the left temporoparietal cortex in consecutive days. AVH severity was assessed at baseline, end of treatment and follow-up using the Psychotic Symptom Rating Scale (PSYRATS) and the Auditory Hallucinations Rating Scale (AHRS). Other schizophrenia-related symptoms were assessed with the Positive and Negative Syndrome Scale (PANSS). RESULTS: Seven patients dropped out before completing the study. In the remaining 64, AVH improved significantly after treatment in both groups as measured with both PSYRATS and AHRS. PANSS positive and general subscores also decreased, but the negative subscores did not. However, improvement did not differ significantly between the TB-rTMS and the placebo group on any outcome measure. CONCLUSIONS: Symptom reduction could be achieved in patients with medication-resistant hallucinations, even within 1 week time. However, as both groups showed similar improvement, effects were general (ie, placebo-effects) rather than specific to treatment with continuous TB-rTMS. Our findings highlight the importance of double-blind trials including a sham-control condition to assess efficacy of new treatments such as TMS.


Assuntos
Alucinações/terapia , Esquizofrenia/terapia , Psicologia do Esquizofrênico , Estimulação Magnética Transcraniana/métodos , Adulto , Método Duplo-Cego , Feminino , Alucinações/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Lobo Parietal , Efeito Placebo , Lobo Temporal , Resultado do Tratamento , Adulto Jovem
10.
Front Psychol ; 6: 244, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25798123

RESUMO

Auditory hallucinations (AH) are a symptom of several psychiatric disorders, such as schizophrenia. In a significant minority of patients, AH are resistant to antipsychotic medication. Alternative treatment options for this medication resistant group are scarce and most of them focus on coping with the hallucinations. Finding an alternative treatment that can diminish AH is of great importance. Transcranial direct current stimulation (tDCS) is a safe and non-invasive technique that is able to directly influence cortical excitability through the application of very low electric currents. A 1-2 mA direct current is applied between two surface electrodes, one serving as the anode and the other as the cathode. Cortical excitability is increased in the vicinity of the anode and reduced near the cathode. The technique, which has only a few transient side effects and is cheap and portable, is increasingly explored as a treatment for neurological and psychiatric symptoms. It has shown efficacy on symptoms of depression, bipolar disorder, schizophrenia, Alzheimer's disease, Parkinson's disease, epilepsy, and stroke. However, the application of tDCS as a treatment for AH is relatively new. This article provides an overview of the current knowledge in this field and guidelines for future research.

11.
Curr Opin Psychiatry ; 28(3): 222-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25768083

RESUMO

PURPOSE OF REVIEW: Despite adequate antipsychotic treatment, 20-30% of patients with schizophrenia fail to obtain remission from psychosis. Physical stimulation treatments may provide an alternative therapy. In this review, we summarize the most recent studies regarding repetitive transcranial magnetic stimulation (rTMS), transcranial direct current stimulation (tDCS) and electroconvulsive therapy (ECT) for medication-resistant psychosis in schizophrenia. RECENT FINDINGS: Stimulation techniques in the treatment of medication-resistant psychosis have shown inconsistent results. Initial results of rTMS for auditory verbal hallucinations (AVH) were promising, but three recent large randomized controlled trials (RCTs) show similar results of rTMS as placebo. tDCS has shown initial promise as a treatment for AVH, but only in case studies and in two small RCTs. Larger studies are needed to define its efficacy. Although psychotic symptoms generally decrease after ECT, its efficacy has not been demonstrated in comparison with placebo. SUMMARY: Although previous meta-analyses indicate significant mean effect sizes for rTMS for intractable AVH, three recent large RCTs indicate no effect compared with placebo. The use of tDCS for resistant AVH and ECT for intractable psychosis has shown some initial promise, but adequately sized placebo-controlled RCTs are now needed. Taken together, the evidence for physical stimulation techniques to relieve medication-resistant psychosis is currently weak.


Assuntos
Eletroconvulsoterapia , Transtornos Psicóticos/terapia , Esquizofrenia/terapia , Estimulação Transcraniana por Corrente Contínua , Estimulação Magnética Transcraniana , Antipsicóticos/administração & dosagem , Alucinações/terapia , Humanos , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento
12.
JAMA Psychiatry ; 72(4): 377-85, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25715178

RESUMO

IMPORTANCE: Patients with 22q11.2 deletion syndrome (22q11DS) have an elevated (25%) risk of developing schizophrenia. Recent reports have suggested that a subgroup of children with 22q11DS display a substantial decline in cognitive abilities starting at a young age. OBJECTIVE: To determine whether early cognitive decline is associated with risk of psychotic disorder in 22q11DS. DESIGN, SETTING, AND PARTICIPANTS: Prospective longitudinal cohort study. As part of an international research consortium initiative, we used the largest data set of intelligence (IQ) measurements in patients with 22q11DS reported to date to investigate longitudinal IQ trajectories and the risk of subsequent psychotic illness. A total of 829 patients with a confirmed hemizygous 22q11.2 deletion, recruited through 12 international clinical research sites, were included. Both psychiatric assessments and longitudinal IQ measurements were available for a subset of 411 patients (388 with ≥1 assessment at age 8-24 years). MAIN OUTCOMES AND MEASURES: Diagnosis of a psychotic disorder, initial IQ, longitudinal IQ trajectory, and timing of the last psychiatric assessment with respect to the last IQ test. RESULTS: Among 411 patients with 22q11DS, 55 (13.4%) were diagnosed as having a psychotic disorder. The mean (SD) age at the most recent psychiatric assessment was 16.1 (6.2) years. The mean (SD) full-scale IQ at first cognitive assessment was lower in patients who developed a psychotic disorder (65.5 [12.0]) compared with those without a psychotic disorder (74.0 [14.0]). On average, children with 22q11DS showed a mild decline in IQ (full-scale IQ, 7.04 points) with increasing age, particularly in the domain of verbal IQ (9.02 points). In those who developed psychotic illness, this decline was significantly steeper (P < .001). Those with a negative deviation from the average cognitive trajectory observed in 22q11DS were at significantly increased risk for the development of a psychotic disorder (odds ratio = 2.49; 95% CI, 1.24-5.00; P = .01). The divergence of verbal IQ trajectories between those who subsequently developed a psychotic disorder and those who did not was distinguishable from age 11 years onward. CONCLUSIONS AND RELEVANCE: In 22q11DS, early cognitive decline is a robust indicator of the risk of developing a psychotic illness. These findings mirror those observed in idiopathic schizophrenia. The results provide further support for investigations of 22q11DS as a genetic model for elucidating neurobiological mechanisms underlying the development of psychosis.


Assuntos
Transtornos Cognitivos/psicologia , Síndrome de DiGeorge/psicologia , Transtornos Psicóticos/psicologia , Adolescente , Fatores Etários , Criança , Cromossomos Humanos Par 22/genética , Transtornos Cognitivos/complicações , Síndrome de DiGeorge/complicações , Feminino , Humanos , Testes de Inteligência , Masculino , Testes Neuropsicológicos , Estudos Prospectivos , Transtornos Psicóticos/complicações , Fatores de Risco , Adulto Jovem
14.
Schizophr Res ; 145(1-3): 27-32, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23375942

RESUMO

INTRODUCTION: Neuroimaging studies investigating auditory verbal hallucinations (AVH) have revealed involvement of several cortical structures. These findings may however be biased by brain activity related to stimulus detection and motor processes associated with the task to indicate the presence of AVH. Disentangling brain activation specifically related to AVH and to additional cognitive processes may help focus on the true neuronal substrates of AVH and strengthen the development of new focal treatment strategies. METHODS: Brain activation during AVH as indicated by button press was compared to brain activation during auditory stimulus detection indicated by button press. We performed two neuroimaging meta-analyses, assessing 10 AVH and 11 auditory stimulus detection studies. A random-effects activation likelihood estimation was performed using GingerALE to assess commonalities and differences across AVH and stimulus detection studies. RESULTS: Activity in the claustrum, pulvinar area, medial geniculum body, pyramis, culmen, putamen, insula, and parahippocampal, medial frontal, precentral, postcentral, superior temporal and right inferior frontal gyri was found to be specifically related to AVH. The pars opercularis of the left inferior frontal gyrus and the left transverse temporal gyrus were activated to a similar extent during AVH and auditory stimulus detection. DISCUSSION: Development of new focal treatment strategies for AVH may focus on the areas uniquely activated in the AVH analysis. The pars opercularis and the transverse temporal gyrus may not be directly involved in the experience of AVH itself, but rather in auditory stimulus detection.


Assuntos
Encéfalo/fisiopatologia , Alucinações/patologia , Alucinações/fisiopatologia , Detecção de Sinal Psicológico/fisiologia , Estimulação Acústica , Encéfalo/irrigação sanguínea , Mapeamento Encefálico , Bases de Dados Factuais/estatística & dados numéricos , Feminino , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Masculino , Oxigênio
15.
Schizophr Res ; 137(1-3): 174-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22289867

RESUMO

OBJECTIVE: Repetitive transcranial magnetic stimulation (rTMS) to the temporoparietal region has been proposed as a therapeutic option for auditory verbal hallucinations (AVH). However, most large randomized controlled trials failed to demonstrate a superior effect of rTMS treatment as compared to sham. Previous studies applied daily rTMS sessions for one or more weeks to summate its effects. However, the effect of a single rTMS treatment on AVH-severity has never been studied, making it unclear if there is an initial effect that could be increased by repeated treatment. METHODS: In three separate sessions, twenty-four patients with a psychotic disorder received 1-Hz rTMS to the left temporoparietal cortex, its right-sided homologue or a centro-occipital control site. Severity of AVH was assessed before and after each rTMS session and resting-state EEGs were recorded to investigate the neuronal effects of rTMS. RESULTS: Stimulation of the temporoparietal cortices was not more effective in reducing AVH-severity than control-site stimulation. In addition, EEG-related power and connectivity measures were not affected differently across stimulation sites and changes in neuronal activity did not correlate with changes in AVH-severity. CONCLUSIONS: These results may suggest a placebo effect of a single session of 1-Hz rTMS treatment on AVH-severity.


Assuntos
Ondas Encefálicas/fisiologia , Eletroencefalografia , Alucinações/terapia , Estimulação Magnética Transcraniana/métodos , Adulto , Análise de Variância , Distribuição de Qui-Quadrado , Feminino , Alucinações/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Desempenho Psicomotor/fisiologia , Esquizofrenia/complicações , Limiar Sensorial , Adulto Jovem
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