Intestinal mycobiota dysbiosis associated inflammation activation in chronic schizophrenia.

The microbiome-gut-brain axis is related to schizophrenia (SCZ). The role of intestinal mycobiota in SCZ has been under investigated. We present a half-year follow-up study involving 109 chronic SCZ patients and 77 healthy controls. Intestinal mycobiota was tested by internal transcribed spacer (ITS). Untargeted liquid chromatography-mass spectrometry (LC-MS) was used to measure fecal metabolites. Symptom severity was assessed using the Positive and Negative Syndrome Scale. Enterotype analysis showed that Candida-type patients exhibited severer positive symptoms and depression factors than Saccharomyces-type patients. Candida and its top species and operational taxonomic units (OTUs) were positively correlated with depression factors (all p=0.001). Fecal metabolites analysis showed that upregulated metabolites were associated with chronic inflammation (NF-κB pathway and T helper cell differentiation), downregulated metabolites were associated with glutamate metabolism, serotonergic and dopaminergic synapse. Procrustes analysis revealed significant correlation between intestinal mycobiota and fecal metabolites (M2=0.937, p<0.001). Metabolic module analysis showed that the top module, MEturquoise (associated with Th1 and Th2 cell differentiation), was negatively correlated with SCZ (r=-0.783, p<0.0001), positively correlated with Candida, Aspergillus, Trichosporon and Talaromyces (decreased in SCZ) and negatively correlated with Saccharomyces (increased in SCZ). We also found impairments of intestinal barrier in SCZ, characterized by increased in blood D-lactate (mucosa impairment marker) and decreased in blood mucin 2 (mucosal barrier protective protein). Serum levels of TNF-α was increased and showed stable high levels during treatment. This study suggests that mycobiota dysbiosis-related chronic inflammation and an impaired intestinal mucosal barrier are associated with chronic SCZ.

Exploring the latent cognitive structure in schizophrenia: implications for antipsychotic treatment responses.

BACKGROUND: Individuals diagnosed with schizophrenia present diverse degrees and types of cognitive impairment, leading to variations in responses to antipsychotic treatments. Understanding the underlying cognitive structures is crucial for assessing this heterogeneity. Utilizing latent profile analysis (LPA) enables the delineation of latent categories of cognitive function. Integrating this approach with a dimensional perspective allows for the exploration of the relationship between cognitive function and treatment response. METHODS: This study examined 647 patients from two distinct cohorts. Utilizing LPA within the discovery cohort (n = 333) and the replication cohort (n = 314), latent subtypes were identified categorically. The stability of cognitive structures was evaluated employing Latent Transition Analysis (LTA). The relationship between cognitive function and treatment response were investigated by comparing Positive and Negative Syndrome Scale (PANSS) reduction rates across diverse cognitive subtypes. Furthermore, dimensional insights were gained through correlation analyses between cognitive tests and PANSS reduction rates. RESULTS: In terms of categorical, individuals diagnosed with schizophrenia can be categorized into three distinct subtypes: those 'without cognitive deficit', those 'with mild-moderate cognitive 'eficit', and those 'with moderate-severe cognitive deficit'. There are significant differences in PANSS reduction rates among patients belonging to these subtypes following antipsychotic treatment (p < 0.05). Furthermore, from a dimensional perspective, processing speed at baseline is positively correlated with PANSS score reduction rates at week 8/week 10 (p < 0.01). CONCLUSIONS: Our findings have unveiled the latent subtypes of cognitive function in schizophrenia, illuminating the association between cognitive function and responses to antipsychotic treatment from both categorical and dimensional perspectives.

Psychosocial and psychological interventions for schizophrenia relapse prevention: A bibliometric analysis.

Various psychosocial and psychological interventions have been developed to reduce schizophrenia relapse prevention. A better understanding of these active interventions is important for clinical practice and for meaningful allocation of resources. However, no bibliometric analysis of this area has been conducted. Studies were retrieved from the Web of Science Core Collection database. The publication outputs and cooperation of institutions were visualized with Origin 2021. Global cooperation was visualized using ArcGIS Pro3.0. VOSviewer was used to generate visualizations of network of authors and keywords. The number of annual publications generally showed a fluctuating upward trend over the past 20 years. Germany published the most relevant articles (361, 26.76%). The Technical University of Munich was the most productive institution (70, 9.86%). Leucht Stefan published the most articles (46, 6.48%) and had the highest number of citations (4,375 citations). Schizophrenia Research published the most studies (39, 5.49%). Keywords were roughly classified into three clusters: cognitive behavioral therapy (CBT), family interventions and family psychoeducation and other factors related to interventions. The findings provided the current status of research on psychosocial and psychological interventions for schizophrenia relapse prevention from a bibliometric perspective. Recent research has mainly focused on CBT, family interventions and family psychoeducation.

Multiomics Analyses Reveal Microbiome-Gut-Brain Crosstalk Centered on Aberrant Gamma-Aminobutyric Acid and Tryptophan Metabolism in Drug-Naïve Patients with First-Episode Schizophrenia.

BACKGROUND AND HYPOTHESIS: Schizophrenia (SCZ) is associated with complex crosstalk between the gut microbiota and host metabolism, but the underlying mechanism remains elusive. Investigating the aberrant neurotransmitter processes reflected by alterations identified using multiomics analysis is valuable to fully explain the pathogenesis of SCZ. STUDY DESIGN: We conducted an integrative analysis of multiomics data, including the serum metabolome, fecal metagenome, single nucleotide polymorphism data, and neuroimaging data obtained from a cohort of 127 drug-naïve, first-episode SCZ patients and 92 healthy controls to characterize the microbiome-gut-brain axis in SCZ patients. We used pathway-based polygenic risk score (PRS) analyses to determine the biological pathways contributing to genetic risk and mediation effect analyses to determine the important neuroimaging features. Additionally, a random forest model was generated for effective SCZ diagnosis. STUDY RESULTS: We found that the altered metabolome and dysregulated microbiome were associated with neuroactive metabolites, including gamma-aminobutyric acid (GABA), tryptophan, and short-chain fatty acids. Further structural and functional magnetic resonance imaging analyses highlighted that gray matter volume and functional connectivity disturbances mediate the relationships between Ruminococcus_torgues and Collinsella_aerofaciens and symptom severity and the relationships between species Lactobacillus_ruminis and differential metabolites l-2,4-diaminobutyric acid and N-acetylserotonin and cognitive function. Moreover, analyses of the Polygenic Risk Score (PRS) support that alterations in GABA and tryptophan neurotransmitter pathways are associated with SCZ risk, and GABA might be a more dominant contributor. CONCLUSIONS: This study provides new insights into systematic relationships among genes, metabolism, and the gut microbiota that affect brain functional connectivity, thereby affecting SCZ pathogenesis.

Metformin improves cognitive impairment in patients with schizophrenia: associated with enhanced functional connectivity of dorsolateral prefrontal cortex.

Cognitive impairment is a core feature of schizophrenia, which is aggravated by antipsychotics-induced metabolic disturbance and lacks effective pharmacologic treatments in clinical practice. Our previous study demonstrated the efficiency of metformin in alleviating metabolic disturbance following antipsychotic administration. Here we report that metformin could ameliorate cognitive impairment and improve functional connectivity (FC) in prefrontal regions. This is an open-labeled, evaluator-blinded study. Clinically stable patients with schizophrenia were randomly assigned to receive antipsychotics plus metformin (N = 48) or antipsychotics alone (N = 24) for 24 weeks. The improvement in cognition was assessed by the MATRICS Consensus Cognitive Battery (MCCB). Its association with metabolic measurements, and voxel-wise whole-brain FC with dorsolateral prefrontal cortex (DLPFC) subregions as seeds were evaluated. When compared to the antipsychotics alone group, the addition of metformin resulted in significantly greater improvements in the MCCB composite score, speed of processing, working memory, verbal learning, and visual learning. A significant time × group interaction effect of increased FC between DLPFC and the anterior cingulate cortex (ACC)/middle cingulate cortex (MCC), and between DLPFC subregions were observed after metformin treatment, which was positively correlated with MCCB cognitive performance. Furthermore, the FC between left DLPFC A9/46d to right ACC/MCC significantly mediated metformin-induced speed of processing improvement; the FC between left A46 to right ACC significantly mediated metformin-induced verbal learning improvement. Collectively, these findings demonstrate that metformin can improve cognitive impairments in schizophrenia patients and is partly related to the FC changes in the DLPFC. Trial Registration: The trial was registered with ClinicalTrials.gov (NCT03271866). The full trial protocol is provided in Supplementary Material.

Corrigendum: The association between metabolic disturbance and cognitive impairments in early-stage schizophrenia.

[This corrects the article DOI: 10.3389/fnhum.2020.599720.].

Gut mycobiota dysbiosis in drug-naïve, first-episode schizophrenia.

Bacterial dysbiosis has been demonstrated in patients with schizophrenia (SCH). The aim of the present study was to investigate alterations in mycobiota composition and fungi-bacteria correlation network in drug-naïve, first episode SCH. We recruited 205 SCH patients and 125 healthy controls (HCs), whose gut bacterial and fungal compositions were characterized by 16S and 18S ribosomal RNA gene amplicon sequencing, respectively. Fungal-bacterial relative correlation network analysis was performed using the Spearman's test and distance correlation. We also computed relative networks connectedness, which represents the ratio of significant interactions (edges) and taxa (nodes) in the network. SCH patients showed lower fungal α-diversity compared with that of HCs. Furthermore, we identified 29 differential fungal markers at multiple taxonomies between SCH patients and HCs. SCH patients also showed a significantly lower fungi-to-bacteria α-diversity ratio compared with that of HCs (p = 1.81 × 10-8). In risk prediction models, we observed that combining bacterial and fungal markers achieved higher accuracy than that of bacterial markers alone (AUC = 0.847 vs AUC = 0.739; p = 0.043). Fungal-bacterial correlation network was denser in HCs than in SCH patients and was characterized by a high number of neighbors (p < 0.05). In addition, an increased abundance of Purpureocillium was associated with more severe psychiatric symptoms and poorer cognitive function in SCH patients (p < 0.05). Our study demonstrated a disrupted and weakened fungi-bacteria network in SCH patients, which might be associated with their clinical manifestations. Future research on fungal-bacterial correlation network is warranted to advance our understanding about the role of mycobiota in the etiology of SCH and to explore novel intervention approaches.

Identifying and revealing different brain neural activities of cognitive subtypes in early course schizophrenia.

Background: Cognitive subtypes of schizophrenia may exhibit different neurobiological characteristics. This study aimed to reveal the underlying neurobiological features between cognitive subtypes in the early course of schizophrenia (ECS). According to prior studies, we hypothesized to identify 2-4 distinct cognitive subtypes. We further hypothesized that the subtype with relatively poorer cognitive function might have lower brain spontaneous neural activity than the subtype with relatively better cognitive function. Method: Cognitive function was assessed by the MATRICS Consensus Cognitive Battery (MCCB). Resting-state functional magnetic resonance imaging scanning was conducted for each individual. There were 155 ECS individuals and 97 healthy controls (HCs) included in the subsequent analysis. Latent profile analysis (LPA) was used to identify the cognitive subtypes in ECS individuals, and amplitude of low-frequency fluctuations (ALFFs) was used to measure brain spontaneous neural activity in ECS individuals and HCs. Results: LPA identified two cognitive subtypes in ECS individuals, containing a severely impaired subtype (SI, n = 63) and a moderately impaired subtype (MI, n = 92). Compared to HCs, ECS individuals exhibited significantly increased ALFF in the left caudate and bilateral thalamus and decreased ALFF in the bilateral medial prefrontal cortex and bilateral posterior cingulate cortex/precuneus (PCC/PCu). In ECS cognitive subtypes, SI showed significantly higher ALFF in the left precentral gyrus (PreCG) and lower ALFF in the left PCC/PCu than MI. Furthermore, ALFFs of left PreCG were negatively correlated with several MCCB cognitive domains in ECS individuals, while ALFF of left PCC/PCu presented opposite correlations. Conclusion: Our findings suggest that differences in the brain spontaneous neural activity of PreCG and PCC/PCu might be the potential neurobiological features of the cognitive subtypes in ECS, which may deepen our understanding of the role of PreCG and PCC/PCu in the pathogenesis of cognitive impairment in schizophrenia.

Altered regional homogeneity and cognitive impairments in first-episode schizophrenia: A resting-state fMRI study.

BACKGROUND: Patients with schizophrenia consistently present pervasive cognitive deficits, but the neurobiological mechanism of cognitive impairments remains unclear. By analyzing regional homogeneity (ReHo) of resting-state functional Magnetic Resonance Imaging, this study aimed to explore the association between brain functional alterations and cognitive deficits in first-episode schizophrenia (FES) with a relatively large sample. METHODS: A total of 187 patients with FES and 100 healthy controls from 3 independent cohorts underwent resting-state functional magnetic resonance scans. The MATRICS Consensus Cognitive Battery (MCCB) was used to assess cognitive function. Partial correlation analysis was performed between abnormal ReHo values and the severity of symptoms and cognitive deficits. RESULTS: Compared with healthy controls, ReHo values increased in right superior frontal cortex and decreased in right anterior cingulate cortex (ACC), left middle occipital gyrus (MOG), left cuneus, right posterior cingulate cortex (PCC), and right superior occipital gyrus in schizophrenia patients. ReHo values in ACC, PCC and superior occipital gyrus were correlated with PANSS scores. In addition, ReHo values in ACC and MOG were negatively correlated with working memory; left cuneus was positively correlated with multiple cognitive domains (speed of processing, attention/vigilance and social cognition); PCC was positively correlated with verbal learning; right superior occipital gyrus was positively correlated with speed of processing and social cognition. CONCLUSION: In conclusion, we found widespread ReHo alterations and cognitive dysfunction in FES. And the pathophysiology mechanism of a wide range of cognitive deficits may be related to abnormal spontaneous brain activity.

Corrigendum: The association between cognitive deficits and clinical characteristic in first-episode drug naïve patients with schizophrenia.

[This corrects the article DOI: 10.3389/fpsyt.2021.638773.].

Corrigendum: The Association Between Cognitive Deficits and Clinical Characteristic in First-Episode Drug Naïve Patients With Schizophrenia.

[This corrects the article DOI: 10.3389/fpsyt.2021.638773.].

Optimizing and Individualizing the Pharmacological Treatment of First-Episode Schizophrenic Patients: Study Protocol for a Multicenter Clinical Trial.

Introduction: Affecting ~1% of the world population, schizophrenia is known as one of the costliest and most burdensome diseases worldwide. Antipsychotic medications are the main treatment for schizophrenia to control psychotic symptoms and efficiently prevent new crises. However, due to poor compliance, 74% of patients with schizophrenia discontinue medication within 1.5 years, which severely affects recovery and prognosis. Through research on intra and interindividual variability based on a psychopathology-neuropsychology-neuroimage-genetics-physiology-biochemistry model, our main objective is to investigate an optimized and individualized antipsychotic-treatment regimen and precision treatment for first-episode schizophrenic patients. Methods and Analysis: The study is performed in 20 representative hospitals in China. Three subprojects are included. In subproject 1, 1,800 first-episode patients with schizophrenia are randomized into six different antipsychotic monotherapy groups (olanzapine, risperidone, aripiprazole, ziprasidone, amisulpride, and haloperidol) for an 8-week treatment. By identifying a set of potential biomarkers associated with antipsychotic treatment response, we intend to build a prediction model, which includes neuroimaging, epigenetics, environmental stress, neurocognition, eye movement, electrophysiology, and neurological biochemistry indexes. In subproject 2, apart from verifying the prediction model established in subproject 1 based on an independent cohort of 1,800 first-episode patients with schizophrenia, we recruit patients from a verification cohort who did not get an effective response after an 8-week antipsychotic treatment into a randomized double-blind controlled trial with minocycline (200 mg per day) and sulforaphane (3 tables per day) to explore add-on treatment for patients with schizophrenia. Two hundred forty participants are anticipated to be enrolled for each group. In subproject 3, we tend to carry out one trial to construct an intervention strategy for metabolic syndrome induced by antipsychotic treatment and another one to build a prevention strategy for patients at a high risk of metabolic syndrome, which combines metformin and lifestyle intervention. Two hundred participants are anticipated to be enrolled for each group. Ethics and Dissemination: The study protocol has been approved by the Medical Ethics committee of the Second Xiangya Hospital of Central South University (No. 2017027). Results will be disseminated in peer-reviewed journals and at international conferences. Trial Registration: This trial has been registered on Clinicalrials.gov (NCT03451734). The protocol version is V.1.0 (April 23, 2017).

The Association Between Cognitive Deficits and Clinical Characteristic in First-Episode Drug Naïve Patients With Schizophrenia.

Background: Schizophrenia is a severe mental disease which characterized by positive symptom, negative symptom, general pathology syndrome and cognitive deficits. In recent years, many studies have investigated the relationship between cognitive deficits and clinical characteristics in schizophrenia, but relatively few studies have been performed on first-episode drug-naïve patients. Methods: Eighty seven first-episode drug-naïve schizophrenia patients were assessed for positive symptom, negative symptom, general pathology symptom and cognitive deficits from the Positive and Negative Symptom Scale and MATRICS Consensus Cognitive Battery. Psychotics depression were assessed using the Calgary depressing scale for schizophrenia. The relationship between clinical characteristics and cognitive deficits were assessed using correlation analysis and linear regression analysis. Results: The prevalence of cognitive deficits among the patients in our study was 85.1% (74/87) which was much higher than that in the general population. According to correlation analysis, negative symptom was negatively correlated with speed of processing and social cognition, and general pathology showed a negative correlation with attention/vigilance. In addition, a positive correlation was found between age and speed of processing. No correlation was found between cognitive deficits and positive symptom. Conclusions: This study confirmed that negative symptom is negatively related with some domains of cognitive function in first-episode drug naïve schizophrenia patients. Trail Registration: NCT03451734. Registered March 2, 2018 (retrospectively registered).

Effects of sulforaphane on cognitive function in patients with frontal brain damage: study protocol for a randomised controlled trial.

INTRODUCTION: Many patients with frontal brain damage show serious cognitive function deficits, which hamper their quality of life and result in poor clinical outcomes. Preclinical research has shown that sulforaphane can significantly improve spatial localisation and working memory impairment after brain injury. The primary aim of this double-blind randomised controlled clinical trial is to assess the efficacy of sulforaphane for improving cognitive function in patients with frontal brain damage. METHODS AND ANALYSIS: Ninety eligible patients will be randomly allocated to an active treatment or a placebo group in a 2:1 ratio. Participants will undergo a series of cognitive and neuropsychiatric tests at baseline (week 0) and after 12 weeks to determine the effect of sulforaphane on cognition. Magnetic resonance spectrum of the brain will be studied using the 3T MRIs of the brain to detect brain metabolites markers, including N-acetyl aspartate, glutamate (Glu), glutathione (GSH) and γ-aminobutyric acid (GABA). Blood brain-derived neurotrophic factor, Glu, GSH and GABA levels and gut microbiota will also be assessed over this period. This study will also evaluate long-term outcomes of brain trauma, brain tumours and cerebrovascular disease via exploratory analyses. The primary outcome will be the difference in scores of a battery of cognitive tests after 12 weeks of sulforaphane treatment. The secondary outcomes will be changes in the Functional Activities Questionnaire (FAQ), the Patient Health Questionnaire (PHQ-9), the Self-Rating Anxiety Scale, the changes in T1-weighted MRI and resting-state functional MRI findings, and changes in brain and blood metabolic markers and gut microbiota at weeks 0 and 12. We expect that sulforaphane will yield favourable results in treating memory and learning deficits for patients with frontal brain damage. Cognitive functional treatment may also improve brain trauma, brain tumours and cerebrovascular outcomes. ETHICS AND DISSEMINATION: The study protocol has been approved by the Medical Ethics committee of the Xiangya Hospital of Central South University (No. 2017121019). The results will be disseminated in peer-reviewed journals and at international conferences. TRIAL REGISTRATION NUMBER: This trial was registered on Clinicaltrials.gov on 31 January 2020 (NCT04252261). The protocol version is V.1.0 (20 December 2019).

Increased Appetite Plays a Key Role in Olanzapine-Induced Weight Gain in First-Episode Schizophrenia Patients

Weight gain and metabolic disturbances, potentially influenced by increased appetite, are common effects of olanzapine treatment in patients with schizophrenia. In this study, we explored the association between olanzapine-induced weight gain and metabolic effects with increased appetite. Drug-naïve, first-episode schizophrenia patients were treated with olanzapine for 12 weeks. Assessments included time to increased appetite, body weight, body mass index, biochemical indicators of blood glucose and lipids, proportion of patients who gained more than 7% or 10% of their baseline weight upon treatment conclusion, patients who developed dyslipidemia, and Positive and Negative Syndrome Scale scores. In total, 33 patients with schizophrenia receiving olanzapine were enrolled and 31 completed the study. During the 12-week olanzapine treatment, 77.4% (24/31) patients had increased appetite with 58.1% (18/31) patients having increased appetite within the first 4 weeks. The mean time for increased appetite was 20.3 days. More patients in the increased appetite group increased their initial body weight by more than 7% after 12 weeks when compared to patients with unchanged appetite (22/24 [91.7%] vs. 3/7 [42.9%], p = 0.004). Earlier increased appetite led to more weight gain during the following month. Overall, 50% of patients in the increased appetite group had dyslipidemia after 12 weeks. Our results demonstrated that olanzapine induced significantly appetite increase in first-episode patients with schizophrenia and appetite increase played a key role in olanzapine-induced weight gain and dyslipidemia. Clinical Trial Registration: NCT03451734. Registered March 2, 2018 (retrospectively registered).

Corrigendum: Increased Appetite Plays a Key Role in Olanzapine-Induced Weight Gain in First-Episode Schizophrenia Patients.

[This corrects the article DOI: 10.3389/fphar.2020.00739.].

The Association Between Metabolic Disturbance and Cognitive Impairments in Early-Stage Schizophrenia.

Background: Cognitive impairment is one of the core symptoms of schizophrenia, which is considered to be significantly correlated to prognosis. In recent years, many studies have suggested that metabolic disorders could be related to a higher risk of cognitive defects in a general setting. However, there has been limited evidence on the association between metabolism and cognitive function in patients with early-stage schizophrenia. Methods: In this study, we recruited 172 patients with early-stage schizophrenia. Relevant metabolic parameters were examined and cognitive function was evaluated by using the MATRICS Consensus Cognitive Battery (MCCB) to investigate the relationship between metabolic disorder and cognitive impairment. Results: Generally, the prevalence of cognitive impairment among patients in our study was 84.7% (144/170), which was much higher than that in the general population. Compared with the general Chinese setting, the study population presented a higher proportion of metabolic disturbance. Patients who had metabolic disturbance showed no significant differences on cognitive function compared with the other patients. Correlation analysis showed that metabolic status was significantly correlated with cognitive function as assessed by the cognitive domain scores (p < 0.05), while such association was not found in further multiple regression analysis. Conclusions: Therefore, there may be no association between metabolic disorder and cognitive impairment in patients with early-stage schizophrenia. Trial Registration: Clinicaltrials.gov, NCT03451734. Registered March 2, 2018 (retrospectively registered).

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Antipsychotic medication is the primary treatment for schizophrenia, which is effective on ameliorating positive symptoms and can reduce the risk of recurrence, but it has limited efficacy for negative symptoms and cognitive dysfunction. The negative symptoms and cognitive dysfunction seriously affects the life quality and social function for the patients with schizophrenia. Currently, there is plenty evidence that antipsychotic drugs combined with adjuvant therapy drugs can effectively improve the negative symptoms and cognitive dysfunction. These drugs include anti-oxidants, nicotinic acetylcholine receptors and neuro-inflammatory drugs (anti-inflammatory drugs, minocycline), which show potential clinical effects.

[Role of sulforaphane in improving negative symptoms and cognitive symptoms of schizophrenia and the underlying mechanism].

The negative symptoms and cognitive symptoms of schizophrenia patients are still clinical problems to be solved. Schizophrenia patients are abnormal in oxidative stress, immune regulation, and anti-histone deacetylase (HDAC), while sulforaphane plays a role in anti-oxidative stress, anti-inflammation, and anti-HDAC. Therefore, the sulforaphane could improve the negative symptoms and cognitive deficits of schizophrenia.

Brain-derived neurotrophic factor is associated with cognitive impairments in first-episode and chronic schizophrenia.

Brain-derived neurotrophic factor (BDNF) may be related to the pathophysiology of schizophrenia. This study aims to examine the relation between plasma BDNF levels and the cognition of patients with schizophrenia. We recruited 31 patients with chronic schizophrenia, 34 first-episode patients, and 35 healthy control subjects. We examined the MATRICS Consensus Cognitive Battery (MCCB) and the plasma BDNF levels in all groups. The schizophrenic symptoms were assessed using the positive and negative syndrome scale. The BDNF levels of schizophrenic patients were remarkably lower than those of the controls. The cognitive MCCB global composite scores and part index scores of schizophrenic patients were remarkably lower than those of the controls. Moreover, remarkable correlations were observed between BDNF levels and partial cognitive dimensions, such as visual learning, memory, and processing speed. Therefore, BDNF may be involved in the pathophysiology and cognitive impairment of schizophrenia.