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OBJECTIVES: A seizure lasting >15 s has been considered to indicate treatment for magnetic seizure therapy (MST), a modification of electroconvulsive therapy (ECT), without much validation. This study aimed to investigate whether this seizure duration was suitable for the treatment of schizophrenia. METHODS: Altogether, 34 and 33 in-patients with schizophrenia received 10 sessions of MST and ECT, respectively. Clinical symptoms were assessed using the Positive and Negative Symptom Scale at baseline and at the 4-week follow-up. Electroencephalogram (EEG) was monitored during each MST or ECT treatment using bifrontal electrodes. RESULTS: The proportion of participants who achieved the 15-second threshold was only 28.6% in the MST group, with a significant difference between responders and nonresponders. For patients receiving MST, the average EEG seizure duration correlated with the percentage of Positive and Negative Symptom Scale reduction (t(32) = 2.51, P = 0.017, uncorrected; t(32) = 2.00, P = 0.055, corrected with clinical characteristics). The average EEG seizure duration predicted the clinical response at a trend level (Z = 1.76, P = 0.078) with an optimal cutoff of 11.3 seconds. All patients in the ECT group achieved the 15-second threshold. However, their average EEG seizure duration was uncorrelated with clinical improvement. CONCLUSIONS: The duration of EEG seizures may be associated with the antipsychotic effects of MST. This association may have been influenced by various clinical and technical factors. More research is needed to define the specific criteria for adequate MST in schizophrenia in order to achieve personalized dosing.
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OBJECTIVE: Previous studies showed alterations of brain function in the ventromedial prefrontal cortex of schizophrenia patients. Also, neurochemical changes, especially GABA level alteration, have been found in the medial prefrontal cortex of schizophrenia patients. However, the relationship between GABA level in the ventromedial prefrontal cortex and brain functional activity in schizophrenia patients remains unexplored. METHODS: In total, 23 drug-naïve, first-episode psychosis patients and 26 matched healthy controls completed the study. The single voxel proton magnetic resonance spectroscopy data were acquired in ventromedial prefrontal cortex region, which was used as the seed region for resting-state functional connectivity analysis. The proton magnetic resonance spectroscopy data were processed to quantify the concentrations of GABA+, glutamine and glutamate, and N-acetylaspartate in ventromedial prefrontal cortex. Spearman correlation analysis was used to examine the relationship between metabolite concentration, functional connectivity and clinical variables. Pearson correlation analysis was used to examine the relationship between GABA+ concentration and functional connectivity value. RESULTS: In first-episode psychosis patients, GABA+ level in ventromedial prefrontal cortex was higher and was positively correlated with ventromedial prefrontal cortex-left middle orbital frontal cortex functional connectivity. N-acetylaspartate level was positively correlated with positive symptoms, and the functional connectivity between ventromedial prefrontal cortex and left precuneus was negatively associated with negative symptoms of first-episode psychosis patients. CONCLUSION: Our results indicated that ventromedial prefrontal cortex functional connectivity changes were positively correlated with higher local GABA+ level in first-episode psychosis patients. The altered neurochemical concentration and functional connectivity provide insights into the pathology of schizophrenia.
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Córtex Pré-Frontal , Transtornos Psicóticos , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Córtex Pré-Frontal/diagnóstico por imagem , Espectroscopia de Prótons por Ressonância Magnética , Transtornos Psicóticos/diagnóstico por imagemRESUMO
Schizophrenia is a psychiatric disorder associated with significant morbidity and mortality. Although antipsychotic medications and electroconvulsive therapy can be used to manage the clinical symptoms of schizophrenia, a substantial portion (10%-30%) of patients do not clinically respond to these treatments or cannot tolerate the side effects. Recently, deep brain stimulation (DBS) has emerged as a promising safe and effective therapeutic intervention for various psychiatric disorders. Here, the authors explore the utility of DBS of the habenula (HB) in the clinical management of 2 young adult male patients with severe, chronic, and treatment-resistant schizophrenia. After HB DBS surgery, both patients experienced improvements in clinical symptoms during the first 6 months of treatment. However, only 1 patient retained the clinical benefits and reached a favorable outcome at 12-month follow-up. The symptoms of the other patient subsequently worsened and became so profound that he needed to be hospitalized at 10-month follow-up and withdrawn from further study participation. It is tentatively concluded that HB DBS could ultimately be a relatively safe and effective surgical intervention for certain patients with treatment-resistant schizophrenia.
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Estimulação Encefálica Profunda , Habenula/fisiopatologia , Esquizofrenia/fisiopatologia , Esquizofrenia/terapia , Encéfalo/fisiopatologia , Encéfalo/cirurgia , Estimulação Encefálica Profunda/efeitos adversos , Humanos , Masculino , Núcleo Accumbens/fisiopatologia , Projetos Piloto , Esquizofrenia/diagnósticoRESUMO
Genome-wide association studies (GWASs) have reported numerous associations between risk variants and Alzheimer's disease (AD). However, these associations do not necessarily indicate a causal relationship. If the risk variants can be demonstrated to be biologically functional, the possibility of a causal relationship would be increased. In this article, we reviewed all of the published GWASs to extract the genome-wide significant (p < 5×10-8) and replicated associations between risk variants and AD or AD-biomarkers. The regulatory effects of these risk variants on the expression of a novel class of non-coding RNAs (piRNAs) and protein-coding RNAs (mRNAs), the alteration of proteins caused by these variants, the associations between AD and these variants in our own sample, the expression of piRNAs, mRNAs and proteins in human brains targeted by these variants, the expression correlations between the risk genes and APOE, the pathways and networks that the risk genes belonged to, and the possible long non-coding RNAs (LncRNAs) that might regulate the risk genes were analyzed, to investigate the potential biological functions of the risk variants and explore the potential mechanisms underlying the SNP-AD associations. We found replicated and significant associations for AD or AD-biomarkers, surprisingly, only at 17 SNPs located in 11 genes/snRNAs/LncRNAs in eight genomic regions. Most of these 17 SNPs enriched some AD-related pathways or networks, and were potentially functional in regulating piRNAs and mRNAs; some SNPs were associated with AD in our sample, and some SNPs altered protein structures. Most of the protein-coding genes regulated by the risk SNPs were expressed in human brain and correlated with APOE expression. We conclude that these variants were most robust risk markers for AD, and their contributions to AD risk was likely to be causal. As expected, APOE and the lipoprotein metabolism pathway possess the highest weight among these contributions.
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Doença de Alzheimer/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Apolipoproteínas E/genética , Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Proteínas/genética , Fatores de RiscoRESUMO
OBJECTIVE: Schizophrenia is associated with impairment in prospective memory, the ability to remember to carry out an intended action in the future. It has been established that cue identification (detection of the cue event signaling that an intended action should be performed) and intention retrieval (retrieval of an intention from long-term memory following the recognition of a prospective cue) are two important processes underlying prospective memory. The purpose of this study was to examine prospective memory deficit and underlying cognitive processes in patients with first-episode schizophrenia. METHODS: This study examined cue identification and intention retrieval components of event-based prospective memory using a dual-task paradigm in 30 patients with first-episode schizophrenia and 30 healthy controls. All participants were also administered a set of tests assessing working memory and retrospective memory. RESULTS: Both cue identification and intention retrieval were impaired in patients with first-episode schizophrenia compared with healthy controls ( ps < 0.05), with a large effect size for cue identification (Cohen's d = 0.98) and a medium effect size for intention retrieval (Cohen's d = 0.62). After controlling for working memory and retrospective memory, the difference in cue identification between patients and healthy controls remained significant. However, the difference in intention retrieval between the two groups was no longer significant. In addition, there was a significant inverse relationship between cue identification and negative symptoms ( r = -0.446, p = 0.013) in the patient group. CONCLUSION: These findings suggest that both cue identification and intention retrieval in event-based prospective memory are impaired in patients with first-episode schizophrenia. Cue identification and intention retrieval could be potentially used as biomarkers for early detection and treatment prognosis of schizophrenia. In addition, addressing cue identification deficit through cognitive enhancement training may potentially improve negative symptoms as well.
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Sinais (Psicologia) , Intenção , Transtornos da Memória/fisiopatologia , Memória Episódica , Rememoração Mental/fisiologia , Esquizofrenia/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Transtornos da Memória/etiologia , Esquizofrenia/complicações , Adulto JovemRESUMO
Objective: The objective of our study was to evaluate whether intermittent theta burst stimulation(iTBS) applied to the regions with the strongest cortico-hippocampal connectivity within the lateral parietal cortical (LPC) or dorsolateral prefrontal cortical (DLPFC) areas in individuals with schizophrenia could enhance associative memory. Methods: We randomized 96 participants with schizophrenia to receive either active iTBS applied to the right DLPFC, left LPC or sham iTBS for 20 days. Clinical and cognitive assessments were performed at baseline and at the end of treatment. The primary outcome was change in associative memory. The secondary outcome was change in other cognitive functions and psychiatric symptoms. Results: In comparison to the sham group, iTBS targeting the right DLPFC or left LPC in schizophrenia did not yield significant improvements in auditory-auditory associative memory (F=1.27, p=0.294), auditory-visual associative memory (F=0.49, p=0.617), or visual-visual associative memory (F=1.094, p=0.347). Furthermore, after adjusting for variables such as education, disease duration, and negative symptoms, no significant changes were observed in any of these three memory domains. Conclusion: Although our study suggests that iTBS applied to the cortical-hippocampal did not lead to a significant change in associative memory. However, further investigation combining hippocampal-targeted iTBS with functional magnetic resonance imaging (fMRI) is warranted to elucidate the regulatory effects of iTBS on hippocampal function. Trial Registration: clinicaltrials.gov NCT03608462.
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Background. Low-intensity transcranial ultrasound stimulation (TUS) could induce both immediate and long-lasting neuromodulatory effects in human brains. Interhemispheric imbalance at prefrontal or motor cortices generally associates with various cognitive decline in aging and mental disorders. However, whether TUS could modulate the interhemispheric balance of excitability in human brain remains unknown.Objective. This study aims to explore whether repetitive TUS (rTUS) intervention can modulate the interhemispheric balance of excitability between bilateral motor cortex (M1) in healthy subjects.Approach. Motor evoked potentials (MEPs) at bilateral M1 were measured at 15 min and 0 min before a 15 min active or sham rTUS intervention on left M1 and at 0 min, 15 min and 30 min after the intervention, and the Chinese version of brief neurocognitive test battery (C-BCT) was conducted before and after the intervention respectively. Cortical excitability was quantified by MEPs, and the long-lasting changes of MEP amplitude was used as an index of plasticity.Results. In the active rTUS group (n= 20), the ipsilateral MEP amplitude increased significantly compared with baselines and lasted for up to 30 min after intervention, while the contralateral MEP amplitude decreased lasting for 15 min, yielding increased laterality between bilateral MEPs. Furthermore, rTUS intervention induced changes in some C-BCT scores, and the changes of scores correlated with the changes of MEP amplitudes induced by rTUS intervention. The sham rTUS group (n= 20) showed no significant changes in MEPs and C-BCT scores. In addition, no participants reported any adverse effects during and after the rTUS intervention, and no obvious temperature increase appeared in skull or brain tissues in simulation.Significance. rTUS intervention modulated the plasticity of ipsilateral M1 and the interhemispheric balance of M1 excitability in human brain, and improved cognitive performance, suggesting a considerable potential of rTUS in clinical interventions.
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Transtornos Mentais , Córtex Motor , Humanos , Córtex Motor/fisiologia , Estimulação Magnética Transcraniana/métodos , Potencial Evocado Motor/fisiologia , Lateralidade Funcional/fisiologiaRESUMO
The effect of antipsychotic medications is critical for the long-term outcome of symptoms and functions during first-episode psychosis (FEP). However, how brain functions respond to the antipsychotic treatment in the early stage of psychosis and its underlying neural mechanisms remain unclear. In this study, we explored the cross-sectional and longitudinal changes of regional homogeneity (ReHo), whole-brain functional connectivity, and network topological properties via resting-state functional magnetic resonance images. Thirty-two drug-naïve FEP patients and 30 matched healthy volunteers (HV) were included, where 23 patients were re-visited with effective responses after two months of antipsychotic treatment. Compared to HV, drug-naive patients demonstrated significantly different patterns of functional connectivity involving the right thalamus. These functional alterations mainly involved decreased ReHo, increased nodal efficiency in the right thalamus, and increased thalamic-sensorimotor-frontoparietal connectivity. In the follow-up analysis, patients after treatment showed reduced ReHo and nodal clustering in visual networks, as well as disturbances of visual-somatomotor and hippocampus-superior frontal gyrus connectivity. The longitudinal changes of ReHo in the visual cortex were associated with an improvement in general psychotic symptoms. This study provides new evidence regarding alterations in brain function linked to schizophrenia onset and affected by antipsychotic medications. Moreover, our results demonstrated that the functional alterations at baseline were not fully modulated by antipsychotic medications, suggesting that antipsychotic medications may reduce psychotic symptoms but limit the effects in regions involved in disease pathophysiology.
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Antipsicóticos , Transtornos Psicóticos , Humanos , Imageamento por Ressonância Magnética/métodos , Antipsicóticos/uso terapêutico , Estudos Transversais , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/tratamento farmacológico , Encéfalo , Mapeamento Encefálico/métodosRESUMO
Impaired associative memory function in patients with schizophrenia has received considerable attention. However, previous studies have primarily concentrated on unisensory materials, which limits our understanding of the broader implications of this impairment. In this study, we sought to expand on this knowledge by examining two types of associative memory domains in individuals with schizophrenia, leveraging both visual (Vis) and auditory (Aud) materials. A total of 32 patients with schizophrenia and 29 healthy controls were recruited to participate in the study. Each participant participated in an experiment composed of three paradigms in which different abstract materials (Aud-Aud, Aud-Vis, and Vis-Vis) were presented. Subsequently, the discriminability scores of the two groups were calculated and compared in different modal tasks. Results from the study indicated that individuals with schizophrenia demonstrated varying degrees of associative memory dysfunction in both the same and cross-modalities, with the latter having a significantly lower score than healthy controls (t = 4.120, p < 0.001). Additionally, the cross-modal associative memory function was significantly and negatively correlated with the severity of negative symptoms among individuals diagnosed with schizophrenia (r = -0.362, p = 0.042). This study provides evidence of abnormalities in the processing and memorization of information that integrates multiple sensory modalities in individuals with schizophrenia. This is of great significance for further understanding the cognitive symptoms and pathological mechanisms of schizophrenia, potentially guiding the development of relevant interventions and treatment methods.
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Esquizofrenia , Humanos , Esquizofrenia/complicações , Esquizofrenia/patologia , Transtornos da Memória/etiologia , Transtornos da Memória/diagnósticoRESUMO
BACKGROUND: Antipsychotic treatment has improved the disrupted functional connectivity (FC) and neurometabolites levels of the default mode network (DMN) in schizophrenia patients, but a direct relationship between FC change, neurometabolic level alteration, and symptom improvement has not been built. This study examined the association between the alterations in DMN FC, the changes of neurometabolites levels in the medial prefrontal cortex (MPFC), and the improvementsinpsychopathology in a longitudinal study of drug-naïve first-episode psychosis (FEP) patients. METHODS: Thirty-two drug-naïve FEP patients and 30 matched healthy controls underwent repeated assessments with the Positive and Negative Syndrome Scale (PANSS) and 3T proton magnetic resonance spectroscopy as well as resting-state functional magnetic resonance imaging. The levels of γ-aminobutyric acid, glutamate, N-acetyl-aspartate in MPFC, and the FC of DMN were measured. After 8-week antipsychotic treatment, 24 patients were re-examined. RESULTS: After treatment, the changes in γ-aminobutyric acid were correlated with the alterations of FC between the MPFC and DMN, while the changes in N-acetyl-aspartate were associated with the alterations of FC between the posterior cingulate cortex/precuneus and DMN. The FC changes of both regions were correlated with patients PANSS positive score reductions. The structural equation modeling analyses revealed that the changes of DMN FC mediated the relationship between the changes of neurometabolites and the symptom improvements of the patients. CONCLUSIONS: The derived neurometabolic-functional changes underlying the clinical recovery provide insights into the prognosis of FEP patients. It is noteworthy that this is an exploratory study, and future work with larger sample size is needed to validate our findings.
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Antipsicóticos , Transtornos Psicóticos , Antipsicóticos/uso terapêutico , Ácido Aspártico , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Rede de Modo Padrão , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Espectroscopia de Prótons por Ressonância Magnética , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/tratamento farmacológico , Descanso , Ácido gama-AminobutíricoRESUMO
Altered network organization and aberrant neurometabolic levels have been associated with schizophrenia. However, modular alterations of functional-neurometabolic coupling in various stages of schizophrenia remain unclear. This longitudinal study enrolled 34 drug-naïve first-episode schizophrenia (FES) patients and 30 healthy controls (HC). The FES patients underwent resting-state functional magnetic resonance imaging (rs-fMRI) and proton magnetic resonance spectroscopy (1H-MRS) at baseline, 2 months, and 6 months of treatment. For 1H-MRS, the concentrations of γ-aminobutyric acid (GABA), N-acetylaspartate (NAA) and glutamate + glutamine in the ventromedial prefrontal cortex region were measured. A graph theoretical approach was applied for functional connectivity-based modular parcellation. We found that intra-default mode network (DMN) connectivity, inter-modular connectivity between the DMN and the hippocampus, and inter-modular connectivity between the DMN and the frontoparietal module were significantly different across 6-month treatment in the FES patients. The inter-module connectivity of the DMN and hippocampus correlated positively with NAA concentration in the HC group, while this correlation was absent in FES patients. This exploratory study suggests an altered modular connectivity in association with neurometabolite concentrations in FES patients and provides insights into multimodal neuroimaging biomarkers in schizophrenia. Future studies with larger sample sizes are needed to consolidate our findings.
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Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Estudos LongitudinaisRESUMO
The aim of this study was to develop a brief version of cognitive assessment test for evaluating the efficacy of treatments targeting cognitive impairments in Chinese schizophrenia patients, to examine its reliability, and establish normative data. Stratified according to age, gender, and educational level, healthy adult subjects were recruited from fifteen institutions in seven administrative regions of China and 723 valid samples were obtained, of which 50 were retested. Generalized Linear Models were conducted to analyze the effects of age, sex, and education. There was no significant difference between genders, while significant effects were demonstrated respectively among age and education on the normative data of C-BCT. The Cronbach α of C-BCT is 0.75, and the test-retest reliability (ICC) ranged from 0.62 to 0.76. Normative data of C-BCT were generated by gender, age and education, and the effects of these demographic factors were analyzed. It revealed good internal consistency and test-retest reliability of C-BCT.
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OBJECTIVE: Abnormalities of static brain activity have been reported in schizophrenia, but it remains to be clarified the temporal variability of intrinsic brain activities in schizophrenia and how atypical antipsychotics affect it. METHODS: We employed a resting-state functional magnetic resonance imaging (rs-fMRI) and a sliding-window analysis of dynamic amplitude of low-frequency fluctuation (dALFF) to evaluate the dynamic brain activities in schizophrenia (SZ) patients before and after 8-week antipsychotic treatment. Twenty-six schizophrenia individuals and 26 matched healthy controls (HC) were included in this study. RESULTS: Compared with HC, SZ showed stronger dALFF in the right inferior temporal gyrus (ITG.R) at baseline. After medication, the SZ group exhibited reduced dALFF in the right middle occipital gyrus (MOG.R) and increased dALFF in the left superior frontal gyrus (SFG.L), right middle frontal gyrus (MFG.R), and right inferior parietal lobule (IPL.R). Dynamic ALFF in IPL.R was found to significant negative correlate with the Scale for the Assessment of Negative Symptoms (SANS) scores at baseline. CONCLUSION: Our results showed dynamic intrinsic brain activities altered in schizophrenia after short term antipsychotic treatment. The findings of this study support and expand the application of dALFF method in the study of the pathological mechanism in psychosis in the future.
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Convergent evidence has suggested a significant effect of antipsychotic exposure on brain structure and function in patients with schizophrenia, yet the characteristics of favorable treatment outcome remains largely unknown. In this work, we aimed to examine how large-scale brain networks are modulated by antipsychotic treatment, and whether the longitudinal changes could track the improvements of psychopathologic scores. Thirty-four patients with first-episode drug-naïve schizophrenia and 28 matched healthy controls were recruited at baseline from Shanghai Mental Health Center. After 8 weeks of antipsychotic treatment, 24 patients were re-scanned. Through a systematical dynamic functional connectivity (dFC) analysis, we investigated the schizophrenia-related intrinsic alterations of dFC at baseline, followed by a longitudinal study to examine the influence of antipsychotic treatment on these abnormalities by comparing patients at baseline and follow-up. A structural connectivity (SC) association analysis was further carried out to investigate longitudinal anatomical changes that underpin the alterations of dFC. We found a significant symptomatic improvement-related increase in the occurrence of a dFC state characterized by stronger inter-network integration. Furthermore, symptom reduction was correlated with increased FC variability in a unique connectomic signature, particularly in the connections within the default mode network and between the auditory, cognitive control, and cerebellar network to other networks. Additionally, we observed that the SC between the superior frontal gyrus and medial prefrontal cortex was decreased after treatment, suggesting a relaxation of normal constraints on dFC. Taken together, these findings provide new evidence to extend the dysconnectivity hypothesis in schizophrenia from static to dynamic brain network. Moreover, our identified neuroimaging markers tied to the neurobiology of schizophrenia could be used as potential indicators in predicting the treatment outcome of antipsychotics.
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Preparações Farmacêuticas , Esquizofrenia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , China , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/tratamento farmacológico , Resultado do TratamentoRESUMO
Prolactin increase is a common side effect in antipsychotic treatment of schizophrenia, which crucially impacts drug choice and treatment compliance. As previous reviews by our group on this topic have included only few Chinese studies, we aimed to compare and rank antipsychotics based on broader evidence. This systematic review pooled data of 92 included studies from previous systematic review by Huhn et al. and 38 newly-added studies from Chinese-database search, including Chinese databases of China National Knowledge Infrastructure (CNKI), WANFANG DATA, WEIPU Journal Net (VIP) and Sino Biomedicine Service System (SinoMed) up to 20 May 2020. We conducted both network meta-analysis (NMA) and pairwise meta-analysis. The primary outcome was prolactin increase (continuous data). We calculated mean differences (MDs) for prolactin level with 95% confidence intervals (CIs) using random-effects model as primary analysis. 130 RCTs with 25,610 participants were included. Newer antipsychotics (risperidone, amisulpride and paliperidone) and older antipsychotics (chlorpromazine, haloperidol and sulpride) increase prolactin levels with large effect sizes. The SMD results were not identical to the MD results because consistency and heterogeneity assumption was tested to be different in calculations. Sensitivity analyses removing two studies with massive baseline imbalance or removing Chinese studies with high risk of bias did not affect the result. In contrast to a previous review clozapine and zotepine were no longer associated with decreased prolactin levels compared to placebo. Risperidone's ranking has more implications supported by CINeMA. This NMA draws the conclusion with larger sample size and extends evidence to more literature in this field.
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Antipsicóticos , Esquizofrenia , Antipsicóticos/efeitos adversos , Humanos , Metanálise em Rede , Prolactina , Risperidona/uso terapêutico , Esquizofrenia/induzido quimicamente , Esquizofrenia/tratamento farmacológicoRESUMO
Abnormal perceptual processing in schizophrenia may contribute to the development of positive symptoms such as hallucinations. Experimental findings suggest that such abnormalities result from impaired processing of local signals into complex cortical representations. Because complex processing is needed to generate the perception of illusory motion from local signals, deteriorated perception of illusory motion would be expected in schizophrenia. However, findings are mixed, and the relationship between complex motion processing and symptoms is unclear. Illusions with multiple flow components (e.g. rotation/expansion) are known to strongly engage specialized complex processing mechanisms that may be abnormal in schizophrenia, but have not yet been investigated. We used a recently constructed paradigm based on the Pinna-Brelstaff illusion to manipulate complex-flow illusory perception in a quantitative manner and probe associations with dimensional symptoms. In 102 patients and 90 controls, perceived speed and perceptual variability for the PBF were measured across a range of parameters. Meanwhile, eye movement was recorded and gaze parameters were analysed to examine effects on illusory perception. Our results showed that patients experienced faster illusory rotation than controls, while they made fewer eye fixations. This heightened illusory perception was significantly correlated with positive and general, but not negative, symptom scores. Our results indicate that unusual processing of complex-flow motion in patients may be specifically related to dimensional symptoms, which could provide a promising strategy for parsing heterogeneity in the schizophrenia syndrome. This further highlights the role of motion perception abnormalities in the pathophysiology of schizophrenia, thus encouraging future investigation into visual remediation therapeutics.
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Ilusões/fisiologia , Percepção de Movimento/fisiologia , Esquizofrenia/diagnóstico , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Esquizofrenia/fisiopatologia , Índice de Gravidade de Doença , Adulto JovemRESUMO
Negative symptoms are the major challenge in clinical management of schizophrenia. Dorsomedial prefrontal cortex (DMPFC) has been suggested to be highly involved in the mechanisms of negative symptoms of schizophrenia. However, the effect of repetitive Transcranial Magnetic Stimulation (rTMS) over DMPFC has not yet been well studied. In this double-blind, randomized controlled rTMS clinical trial, thirty-three participants (17 in active group and 16 in sham group) were enrolled. This study includes the rTMS treatment phase (lasts for 4 weeks) and a subsequently naturalistic follow-up phase (lasts for another 4 weeks). Schizophrenia patients with prominently negative symptoms were randomly assigned to receive 10 Hz or sham rTMS intervention. The score change in Scale of Negative Symptoms (SANS) was defined as the primary outcome measure. There was a significant decrease in negative symptoms, especially affective flattening and anhedonia in schizophrenia patients after DMPFC-rTMS intervention. Moreover, the negative symptoms improvement could maintain at least another 4 weeks. In addition, no memory impairment or serious adverse reaction of rTMS emerged. Our results suggest that high frequency rTMS over DMPF may represent a safe and effective treatment for negative symptoms in patients with schizophrenia.
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Esquizofrenia , Estimulação Magnética Transcraniana , Método Duplo-Cego , Humanos , Córtex Pré-Frontal , Esquizofrenia/terapia , Resultado do TratamentoRESUMO
BACKGROUND: Brain dynamics abnormalities in the triple-network, which involves the salience network (SN), the default mode network (DMN) and the central executive network (CEN), have been reported in schizophrenia. However, it remains to be clarified how antipsychotics affect dynamic functional connectivity (DFC) within the triple-network and whether differences in clinical outcomes are associated with varying levels of network model dysfunction. METHODS: Resting-state functional magnetic resonance imaging scans were obtained from 64 first-episode schizophrenia patients (SZ) and 67 healthy controls (HC). All patients were scanned before and after 12-week antipsychotic treatment and the HC were scanned only at baseline. RESULTS: At baseline, SZ participants showed significantly reduced dynamic functional interactions across the triple-network compared to HC. The SZ group displayed a pattern of reduction in resting-state DFC among the triple-network compared with HC. After medication, the mean dynamic network interaction index (dNII) value was improved. A significant quadratic relation was observed between longitudinal change of mean dNII and the reduction ratio of PANSS total score within the SZ group. The DFC within inter-network (between DMN and SN, and between DMN and CEN) and intra-network connections of DMN were significantly higher relative to baseline. Intra-SN DFC, intra-DMN DFC and DFC between SN and DMN were found to be predictive of clinical features at baseline. Intra-CEN DFC and DFC between DMN and CEN were predictive of treatment response. CONCLUSIONS: Aberrant brain dynamics in the triple-network could be regulated with medication. DFC organization in the triple network was found to predict the clinical outcome.
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Antipsicóticos , Esquizofrenia , Antipsicóticos/uso terapêutico , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/tratamento farmacológicoRESUMO
Background: Magnetic seizure therapy (MST) is a potential alternative to electroconvulsive therapy (ECT). However, reports on the use of MST for patients with schizophrenia, particularly in developing countries, which is a main indication for ECT, are limited. Methods: From February 2017 to July 2018, 79 inpatients who met the DSM-5 criteria for schizophrenia were randomized to receive 10 sessions of MST (43 inpatients) or ECT (36 inpatients) over the course of 4 weeks. At baseline and 4-week follow-up, the Positive and Negative Syndrome Scale (PANSS) and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) were used to assess symptom severity and cognitive functions, respectively. Results: Seventy-one patients who completed at least half of the treatment protocol were included in the per-protocol analysis. MST generated a non-significant larger antipsychotic effect in terms of a reduction in PANSS total score [g = 0.17, 95% confidence interval (CI) = -0.30, 0.63] and response rate [relative risk (RR) = 1.41, 95% CI = 0.83-2.39]. Twenty-four participants failed to complete the cognitive assessment as a result of severe psychotic symptoms. MST showed significant less cognitive impairment over ECT in terms of immediate memory (g = 1.26, 95% CI = 0.63-1.89), language function (g =1.14, 95% CI = 0.52-1.76), delayed memory (g = 0.75, 95% CI = 0.16-1.35), and global cognitive function (g = 1.07, 95% CI = 0.45-1.68). The intention-to-treat analysis generated similar results except for the differences in delayed memory became statistically insignificant. Better baseline cognitive performance predicted MST and ECT response. Conclusions: Compared to bitemporal ECT with brief pulses and age-dose method, MST had similar antipsychotic efficacy with fewer cognitive impairments, indicating that MST is a promising alternative to ECT as an add-on treatment for schizophrenia. Clinical Trial Registration: ClinicalTrials.gov, identifier: NCT02746965.
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Accumulated studies have investigated pharmacological interventions for first-episode schizophrenia (FES) patients. However, studies on subsequent treatment steps, which are essential to guide clinicians, are largely missing. This Sequential Multiple-Assignment Randomized Trials comparing Antipsychotic Treatments (SMART-CAT) program intends to evaluate the effectiveness of commonly used antipsychotic drugs in FES patients. The major goals of this study are to examine: 1) what would be the optimal subsequent sequential treatment if the first antipsychotic drug failed; 2) whether clozapine could be used in those first-trial failed and have superior efficacy compared to other atypical antipsychotics. In this article we will report the detail protocol of SMART-CAT. The SMART-CAT is a randomized controlled clinical multicenter trial in which 9 institutions in China will participate. A total of 720 FES patients will be enrolled and followed up for 12 months in this study. The trial includes three treatment phases (each phase lasting for 8 weeks) and a naturalistic follow-up phase; participants who do well on an assigned treatment will remain on that treatment for the duration of the 12-month treatment period, while non-responders will move to the next phase of the study to receive a new treatment. Phase 1 is a randomized controlled trial; patients will be randomly assigned to one of the treatments with oral olanzapine, risperidone, amisulpride, aripiprazole or perphenazine. Subjects who fail to respond after 8 weeks will enter the phase 2 randomization. Phase 2 is an equipoise-stratified randomization trial, and patients will be randomly assigned to oral olanzapine, amisulpride or clozapine for 8 weeks. Subjects who fail to respond after phase 2 will enter an open label trial (phase 3); patients who receive clozapine in phase 2 and fail to respond will be assigned to an extended clozapine treatment or modified electroconvulsive therapy add-on therapy (Phase 3A). Patients who were not assigned to clozapine in phase 2 will be assigned to treatment with clozapine or another SGAs not previously used in phase 1 and 2 (Phase 3B). The primary outcome for the treatment phase is the treatment efficacy rate, which is defined as at least 40% reduction in Positive and Negative Syndrome Scale (PANSS) total score. We hypothesize that clozapine is more therapeutically effective than any other SGAs to patients who failed to meet efficacy criteria in Phase 1, and earlier treatment with clozapine can improve the functional outcomes of schizophrenia patients. As for the naturalistic follow-up phase, time to all-cause treatment failure, marked by its discontinuation is selected as the primary outcome, since it reflects both efficacy and side effects. The all-cause discontinuation is defined as discontinuing for any reasons, including poor efficacy, intolerance of adverse reactions, poor compliance and other reasons. The results of the SMART-CAT trial will provide evidence for the selection of antipsychotics in FES patients who fail to respond to the first trial of an antipsychotic drug. It will also provide evidence for the efficacy and safety of using clozapine in the early phase of schizophrenia treatment by comparing with other SGAs. The study is based on the combination of sequential therapy and dynamic therapy, which can be more suitable to assess the effectiveness of treatment options in the real-world clinical setting. As a result, we hope that this study can provide guidance for an optimal treatment algorithm in first-episode schizophrenia patients. Trial registration: ID NCT03510325 in ClinicalTrials.gov.