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Abstract Aim The etiology of bipolar disorder (BD) remains unknown; however, lipid abnormalities in BD have received increasing attention in recent years. In this study, we examined the expression levels of enzyme proteins associated with the metabolic pathway of phosphoinositides (PIs) and their downstream effectors, protein kinase B (Akt1) and glycogen synthase kinase 3β (GSK3β), which have been assumed to be the targets of mood stabilizers such as lithium, in the postmortem brains of patients with BD. Methods The protein expression levels of phosphatidylinositol 4‐phosphate 5‐kinase type‐1 gamma (PIP5K1C), phosphatidylinositol 4‐kinase alpha (PIK4CA), phosphatase and tensin homolog deleted from chromosome 10 (PTEN), Akt1, and GSK3β were measured using enzyme‐linked immunosorbent assays and multiplex fluorescent bead‐based immunoassays in the prefrontal cortex (PFC). Specifically, PTEN, Akt1, GSK3β, and PIP5K1C were measured in seven BD patients and 48 controls. Additionally, PIK4CA was analyzed in 10 cases and 34 controls. Results PTEN expression levels were markedly decreased in the PFCs of patients with BD, whereas those of Akt and GSK3β were prominently elevated. Moreover, patients medicated with lithium exhibited higher Akt1 expression levels and lower PTEN expression levels in comparison with the untreated group. Conclusion Our results suggest that the expression levels of Akt1/GSK3β and its upstream regulator PTEN are considerably altered.

Abstract Establishing a brain biomarker for schizophrenia is strongly desirable not only to support diagnosis by psychiatrists but also to help track the progressive changes in the brain over the course of the illness. A brain morphological signature of schizophrenia was reported in a recent study and is defined by clusters of brain regions with reduced volume in schizophrenia patients compared to healthy individuals. This signature was proven to be effective at differentiating patients with schizophrenia from healthy individuals, suggesting that it is a good candidate brain biomarker of schizophrenia. However, the longitudinal characteristics of this signature have remained unclear. In this study, we examined whether these changes occurred over time and whether they were associated with clinical outcomes. We found a significant change in the brain morphological signature in schizophrenia patients with more brain volume loss than the natural, age‐related reduction in healthy individuals, suggesting that this change can capture a progressive morphological change in the brain. We further found a significant association between changes in the brain morphological signature and changes in the full‐scale intelligence quotient (IQ). The patients with IQ improvement showed preserved brain morphological signatures, whereas the patients without IQ improvement showed progressive changes in the brain morphological signature, suggesting a link between potential recovery of intellectual abilities and the speed of brain pathology progression. We conclude that the brain morphological signature is a brain biomarker that can be used to evaluate progressive changes in the brain that are associated with cognitive impairment due to schizophrenia.

Abstract Aims Schizophrenia is a psychiatric disorder presenting a lack of insight. Although insight changes over time, longitudinal studies of insight in schizophrenia are scarce. Furthermore, most previous studies on insight and intelligence have not measured full‐scale IQ and have not been able to examine the relationship between detailed dimensions of cognitive function and insight. In this study, we assessed insight at two time points and assessed dimensions of cognitive function. Methods A total of 163 patients with schizophrenia participated in the study. We evaluated insight at two time points to understand the patterns of change and examined the association between insight and clinical variables. Additionally, we examined the relationship between the dimensions of cognitive function and insight. Results The patients were divided into three groups based on their change in insight over time: stable at a low level of insight (poor insight), stable at a high level of insight (good insight), and changed in insight over time (unstable insight). Those in the poor insight group had lower general intelligence scores than those in the good insight and unstable insight groups. Regarding cognitive function, verbal comprehension was associated with the level of insight at baseline and follow‐up. Regarding psychiatric symptoms, the poor insight group exhibited more severe symptoms than the other two groups, especially regarding positive symptoms. Conclusions Our classification of patients based on changes in insight revealed that poor insight patients had impaired cognitive function, especially verbal comprehension, and more severe positive symptoms than good insight or unstable insight patients.

Abstract Aims Schizophrenia is a chronic relapsing psychiatric disorder that is characterized by many symptoms and has a high heritability. There were studies showing that the phospholipid abnormalities in subjects with schizophrenia (Front Biosci, S3, 2011, 153; Schizophr Bull, 48, 2022, 1125; Sci Rep, 7, 2017, 6; Anal Bioanal Chem, 400, 2011, 1933). Disturbances in prefrontal cortex phospholipid and fatty acid composition have been reported in subjects with schizophrenia (Sci Rep, 7, 2017, 6; Anal Bioanal Chem, 400, 2011, 1933; Schizophr Res, 215, 2020, 493; J Psychiatr Res, 47, 2013, 636; Int J Mol Sci, 22, 2021). For exploring the signaling pathways contributing to the lipid changes in previous study (Sci Rep, 7, 2017, 6), we performed two types of transcriptome analyses in subjects with schizophrenia: an unbiased transcriptome analysis solely based on RNA‐seq data and a correlation analysis between levels of gene expression and lipids. Methods RNA‐Seq analysis was performed in the postmortem prefrontal cortex from 10 subjects with schizophrenia and 5 controls. Correlation analysis between the transcriptome and lipidome from 9 subjects, which are the same samples in the previous lipidomics study (Sci Rep, 7, 2017, 6). Results Extraction of differentially expressed genes (DEGs) and further sequence and functional group analysis revealed changes in gene expression levels in phosphoinositide 3‐kinase (PI3K)‐Akt signaling and the complement system. In addition, a correlation analysis clarified alterations in ether lipid metabolism pathway, which is not found as DEGs in transcriptome analysis alone. Conclusions This study provided results of the integrated analysis of the schizophrenia‐associated transcriptome and lipidome within the PFC and revealed that lipid‐correlated alterations in the transcriptome are enriched in specific pathways including ether lipid metabolism pathway.

Abstract Aim This study aimed to clarify the abnormalities in dopamine transporter (DAT) availability in drug‐naive adult patients with attention‐deficit/hyperactivity disorder (ADHD) and the relationship between ADHD symptoms and abnormalities in DAT availability. Methods Single‐photon emission tomography (SPECT) was performed using iodine‐123‐β‐carbomethoxy‐3β‐(4‐iodophenyltropane) (I‐123 β CIT) as a tracer to measure in vivo DAT availability in 20 drug‐naive patients with ADHD [mean age ± standard deviation (SD)]: 25 ± 3.44 years; male:female = 11:9] and 20 age‐ and sex‐matched healthy controls (HCs) (mean age ± SD: 23.9 ± 2.27 years). Comparisons of DAT availability between HCs and adult patients with ADHD and the association between symptom severity and DAT availability within the ADHD group were analyzed using Statistical Parametric Mapping 12. Results Drug‐naive adults with ADHD showed significantly reduced DAT availability in the bilateral nucleus accumbens compared with HCs. Correlation analyses revealed a negative correlation between the severity of inattentive symptoms in adult patients with ADHD and DAT availability in the bilateral heads of the caudate nucleus, indicating the association between severe inattentive symptoms and lower DAT availability in the caudate nucleus. Conclusion In drug‐naive adult patients with ADHD, DAT availability was reduced in the nucleus accumbens, an important part of the reward system. This finding indicates the importance of the DAT in the reward system in the pathogenesis of ADHD. Inattentiveness was associated with DAT availability in the caudate nucleus, suggesting involvement of the cortico‐striato‐thalamo‐cortical circuit.

Abstract Aim Delusions are a common symptom in schizophrenia. Some scales have been developed to measure delusional tendencies in healthy people, and nonpathological delusional thinking can occur even among these individuals. The existing scales measure the presence and frequency of delusional thoughts, distress levels, and confidence levels. However, these scales are limited because they do not consider the context of the delusions (i.e., where, with whom, and when). In this study, we developed a new scale that presents detailed scenes using illustrations and sentences and measures the tendency toward delusional interpretations. Methods Factor analysis was conducted to confirm the factor structure of the new scale. To examine the validity of the scale, we analyzed the correlations between delusional tendencies and related variables and verified the consistency between the current scale and previously developed tools. Results Factor analysis confirmed that the new scale has a two‐factor structure, including “internal attribution and paranoid tendency” and “external attribution tendency.” The new scale was found to have acceptable reliability and validity. The internal attribution and paranoid tendency factor was negatively correlated with self‐esteem and decentering. Furthermore, the internal attribution and paranoid tendency factor showed a moderate positive correlation with depressive state and anxiety tendency and a very weak positive correlation with experiences of bullying or harassment. Conclusion The correlations between the new scale and related variables confirmed the construct validity and replicated the results reported in previous studies. This new scale enables the measurement of delusional tendencies in healthy subjects based on the social context.

Abstract Aim Treatment guidelines are designed to assist patients and health care providers and are used as tools for making treatment decisions in clinical situations. The treatment guidelines of the Japanese Society of Mood Disorders establish treatment recommendations for each severity of depression. The individual fitness score (IFS) was developed as a simple and objective indicator to assess whether individual patients are practicing treatment by the recommendations of the depression treatment guidelines of the Japanese Society of Mood Disorders. Methods The EGUIDE project members determined the IFS through the modified Delphi method. In this article, the IFS was calculated based on the treatment of depressed patients treated and discharged between 2016 and 2020 at facilities participating in the EGUIDE project. In addition, we compared scores at admission and discharge. Results The study included 428 depressed patients (mild n = 22, moderate/severe n = 331, psychotic n = 75) at 57 facilities. The mean IFS scores by severity were statistically significantly higher at discharge than at admission with moderate/severe depression (mild 36.1 ± 34.2 vs. 41.6 ± 36.9, p = 0.49; moderate/severe 50.2 ± 33.6 vs. 55.7 ± 32.6, p = 2.1 × 10–3; psychotic 47.4 ± 32.9 versus 52.9 ± 36.0, p = 0.23). Conclusion We developed the IFS based on the depression treatment guideline, which enables us to objectively determine how close the treatment is to the guideline at the time of evaluation in individual cases. Therefore, the IFS may influence guideline‐oriented treatment behavior and lead to the equalization of depression treatment in Japan, including pharmacotherapy.

Abstract To disseminate, educate, and validate psychiatric clinical practice guidelines, the Effectiveness of Guidelines for Dissemination and Education in Psychiatric Treatment (EGUIDE) project was launched in 2016. In this study, we investigated whether the web‐based courses offered by this project would be as effective as the face‐to‐face courses. We analyzed and compared survey answers about overall participant satisfaction with the course and answers regarding clinical knowledge of schizophrenia and major depressive disorder between 170 participants who took the web‐based courses in 2020 and 689 participants who took the face‐to‐face courses from 2016 to 2019. The web‐based course participants completed the survey questions about satisfaction with the web‐based courses. The web‐based courses were conducted using a combination of web services to make it as similar as possible to the face‐to‐face courses. The degree of satisfaction assessed by the general evaluation of the web‐based courses was higher than what was expected from the face‐to‐face courses. The degree of satisfaction was similar for the courses on schizophrenia and major depressive disorder. In addition, there were no significant differences in overall satisfaction and clinical knowledge between web‐based and face‐to‐face courses. In conclusion, the web‐based courses on clinical practice guidelines provided by the EGUIDE project were rated as more satisfying than the face‐to‐face course that the participants expected to take and no differences in the effectiveness of either course. The results suggest that, after the COVID‐19 pandemic, it would be possible to disseminate this educational material more widely by adopting web‐based courses additionally face‐to‐face courses.

Abstract Aims The Guidelines for the Pharmacotherapy of Schizophrenia were established to improve the quality of medical care, and the EGUIDE project was conducted to train clinicians on guideline usage. A quality indicator (QI) was established to measure the prevalence of the guidelines, and a survey was conducted, which revealed a gap between the guidelines and actual clinical practice (evidence‐practice‐gap). The purpose of this study was to develop an individual fitness score (IFS) formula that expresses the degree to which prescribers adhere to the Guidelines for Pharmacological Therapy of Schizophrenia in a simple manner, and to determine the validity of this formula from a survey of the prescriptions of the EGUIDE project participants'. Methods To establish appropriate scores, members discussed the proposed formula and then voted on them. The IFS formula developed was set up so that antipsychotic monotherapy would be given 100 points, with points deducted if concomitant or adjunctive antipsychotic medications were used, and a minimum score of 0. To validate this formula, prescriptions of hospitalized schizophrenic patients at admission and at discharge were scored and compared. Result IFS points vary and ranged from 0 to100. The average pre‐admission score for all subjects was 45.6, and the average score at discharge was 54, those were significantly higher during discharge. Conclusions We developed an IFS formula, a tool to easily visualize the degree to which current prescriptions conform to the guidelines for the pharmacological treatment of schizophrenia.

Abstract The Effectiveness of Guidelines for Dissemination and Education in psychiatric treatment (EGUIDE) project, which is a nationwide dissemination and implementation program for clinical practice guidelines (CPGs) in the field of psychiatry, is currently ongoing. In the current study, a subjective assessment of the participants in the EGUIDE programs was assessed using a questionnaire. Then, the relationships between the subjective assessment, the characteristics of the participants, and the clinical knowledge of the CPGs were evaluated. More than 90% of the participants gave a high rating for the components of content, recommendation, knowledge, skill, and adherence, but not for the component of confidence. A positive correlation was found between years of professional experience and the score of confidence. These results suggest that it may be necessary to apply the knowledge and skills of CPGs obtained in the education programs into practice to increase confidence in the proper use of psychiatric therapies based on CPGs.

Abstract Aim Social functioning is influenced by various factors. Autistic traits could be one of the factors that affect social functioning. Methods In the present study, the relationship between autistic traits and social functioning among 755 healthy individuals was analyzed. Autistic traits were assessed with the autism‐spectrum quotient. Social functioning was assessed by the social functioning scale and the social activity assessment. Results The Autism‐Spectrum Quotient total score was significantly negatively correlated with the social functioning scale total and all subscales of the social functioning scale. All subscales of the Autism‐Spectrum Quotient except attention to detail were significantly negatively correlated with the social functioning scale total score. However, the Autism‐Spectrum Quotient was not correlated with the social activity assessment, which indicates labor functioning. Conclusion Autistic traits of healthy individuals had a negative impact on situations in real life through social functioning for daily life‐sustaining. The effect was not enough to affect labor functioning as indicated by working hours in healthy individuals. These findings should also be examined in individuals with autism spectrum disorder in future studies.

Abstract Background The decision to initiate clozapine treatment should be made on an individual basis and may be closely related to the early detection of treatment‐resistant schizophrenia (TRS), although there is evidence that the early use of clozapine results in a better response to treatment. Therefore, we investigated the relationship between the examination rate of TRS and the prescription rate of clozapine. Methods After attending a 1‐day educational program on schizophrenia based on the "Guidelines for the Pharmacological Treatment of Schizophrenia," we asked the participating facilities to submit records of whether or not TRS was evaluated for each patient. We calculated the clozapine prescription rate from the schizophrenic patients prescribed clozapine and all of the schizophrenic patients. Forty‐nine facilities in 2017 were included in the study. Results There were dichotomous distributions in the examination rate of TRS and a non‐normal distribution in the prescription rate of clozapine. There was a significant correlation between the prescription rate of clozapine and the examination rate of TRS (r s = 0.531, P = 1.032 × 10−4). A significant difference was found in the prescription rate of clozapine between the three groups of facilities according to the examination rate of TRS. Conclusion As a preliminary problem for the use of clozapine, in Japan, the examination rate of TRS varies, and there are many facilities that typically do not consider the possibility of TRS; this trend leads to a low rate of clozapine use. Clearly, further clinician training is needed for the early detection and appropriate management of TRS that includes an explanation of TRS and how to introduce clozapine therapy to patients and their families.

Abstract Aim Clozapine is currently the only effective drug for treatment‐resistant schizophrenia; nonetheless, its pharmacological mechanism remains unclear, and its administration is limited because of severe adverse effects. By comparing the binding proteins of clozapine and its derivative olanzapine, which is safer but less effective than clozapine, we attempted to clarify the mechanism of action specific to clozapine. Methods First, using the polyproline rod conjugates attached with clozapine or olanzapine, clozapine‐binding proteins in extracts from the cerebra of 7‐week‐old ICR mice were isolated and separated by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) and analyzed by liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) to identify proteins. Second, the effect of clozapine on tubulin polymerization was determined turbidimetrically. Finally, the cellular effects of clozapine were observed in HeLa cells by immunofluorescence microscopy. Results Alpha and β tubulins were the most abundant clozapine‐binding proteins. We also found that clozapine directly binds with α and β tubulin heterodimers to inhibit their polymerization to form microtubules and disturbs the microtubule network, causing mitotic arrest in HeLa cells. Conclusion These results suggest that α and β tubulin heterodimers are targeted by the clozapine and the microtubules are involved in the etiology of schizophrenia.

Abstract Background To implement clinical practice guidelines (CPGs), it is necessary for psychiatrists to deepen their understanding of the CPGs. The Effectiveness of Guidelines for Dissemination and Education in Psychiatric Treatment (EGUIDE) project is a nationwide dissemination and implementation study of two sets of CPGs for schizophrenia and major depressive disorder (MDD). Methods A total of 413 psychiatrists (n = 212 in 2016; n = 201 in 2017) learned the two CPGs in the education program of the EGUIDE project, and clinical knowledge of these CPGs was evaluated at baseline and after the programs. To improve the correct answer rate for clinical knowledge after the programs, we revised the lecture materials associated with items that had a low correct answer rate in 2016 and used the revised lecture materials with the CPGs in 2017. The rates of correct answers after the programs between the 2016 and 2017 groups were compared. Results The correct answer rate of one item on the schizophrenia CPG and one item on the MDD CPG tended to be improved (S‐D5 and D‐C6) and that of one on the MDD CPG was significantly improved (D‐D3, P = 0.0008) in the 2017 group compared to those in the 2016 group. Conclusions We reported improvements in clinical knowledge of CPGs after the EGUIDE program in the 2017 group following revision of the lecture materials based on results from the 2016 group. These attempts to improve the degree of understanding of CPGs may facilitate the successful dissemination and implementation of psychiatric guidelines in everyday practice.

Abstract Abnormal eye movements are often associated with psychiatric disorders. Eye movements are sensorimotor functions of the brain, and aging and sex would affect their characteristics. A precise understanding of normal eye movements is required to distinguish disease‐related abnormalities from natural differences associated with aging or sex. To date, there is no multicohort study examining age‐related dependency and sex effects of eye movements in healthy, normal individuals using large samples to ensure the robustness and reproducibility of the results. In this study, we aimed to provide findings showing the impact of age and sex on eye movement measures. The present study used eye movement measures of more than seven hundred healthy individuals from three large independent cohorts. We herein evaluated eye movement measures quantified by using a set of standard eye movement tests that have been utilized for the examination of patients with schizophrenia. We assessed the statistical significance of the effects of age and sex and its reproducibility across cohorts. We found that 4‐18 out of 35 eye movement measures were significantly correlated with age, depending on the cohort, and that 10 of those, which are related to the fixation and motor control of smooth pursuit and saccades, showed high reproducibility. On the other hand, the effects of sex, if any, were less reproducible. The present results suggest that we should take age into account when we evaluate abnormalities in eye movements.

Abstract Background Guideline for Pharmacological Therapy for Schizophrenia was published by the Japanese Society of Neuropsychopharmacology in 2015. “Effectiveness of Guidelines for Dissemination and Education in psychiatric treatment (EGUIDE)” project aimed to standardize medical practice using quality indicators (QIs) as indices to evaluate the quality of medical practice. In this study, we have reported the quality indicator values of prescription before the beginning of the guideline lectures in the EGUIDE project to ascertain the baseline status of treating patients with schizophrenia. Methods A cross‐sectional, retrospective case record survey was conducted, involving 1164 patients with schizophrenia at the time of discharge. We checked all types and dosage of psychotropic drugs. Results Forty‐three percent of patients had antipsychotic polypharmacy, and substantial concomitant medication was observed (antidepressants; 8%, mood stabilizers: 37%, anxiolytics or hypnotics: 68%). Conclusions In the results obtained in this study, we plant to report changes in the effectiveness of education in the EGUIDE project near the future.