Impact of clozapine once-daily versus multiple-daily dosing regimen on relapse in patients with treatment-resistant schizophrenia: A 1-year retrospective cohort study.

RATIONALE: Clozapine, the standard treatment for treatment-resistant schizophrenia (TRS), is generally recommended in a multiple-daily dosing regimen. However, it is commonly administered once daily in clinical practice. Few studies have compared the longitudinal clinical outcomes of these two dosing regimens. OBJECTIVE: To investigate the effect of once-daily versus multiple-daily dosing regimens of clozapine on relapse in patients with TRS. METHODS: This retrospective cohort study included patients with TRS who commenced treatment with clozapine during hospitalization and were discharged between April 2012 and January 2022 from a tertiary psychiatric hospital in Japan. Relapse, defined as a psychiatric exacerbation requiring re-hospitalization within the first-year post-discharge, was analyzed. Multivariable Cox proportional hazards regression analysis compared the relapse risk between once-daily and multiple-daily dosing regimens. A subgroup analysis was conducted to examine the potential interactions between dosing regimen and dose category (low versus high dose). RESULTS: Among 179 patients, 107 (59.8%) received clozapine once daily. No significant difference in the relapse risk was observed between once-daily and multiple-daily dosing regimens (adjusted hazard ratio [aHR]: 1.16; 95% confidence interval [CI]: 0.68-1.99; p = 0.58). However, in patients receiving high doses of clozapine (> 300 mg/day), multiple-daily dosing increased the relapse risk compared to once-daily dosing (aHR: 2.23; 95% CI: 1.00-4.97; p = 0.049). CONCLUSIONS: Once-daily clozapine dosing may not be associated with an increased relapse risk. The increased relapse risk in high-dose multiple-daily dosing may be confounded by unmeasured non-adherence. Further randomized controlled trials are required to validate these findings.

Socially activated neurons in the anterior cingulate cortex are essential for social behavior in mice.

Social behavior, defined as any mode of communication between conspecifics is regulated by a widespread network comprising multiple brain structures. The anterior cingulate cortex (ACC) serves as a hub region interconnected with several brain regions involved in social behavior. Because the ACC coordinates various behaviors, it is important to focus on a subpopulation of neurons that are potentially involved in social behavior to clarify the precise role of the ACC in social behavior. In this study, we aimed to analyze the roles of a social stimulus-responsive subpopulation of neurons in the ACC in social behavior in mice. We demonstrated that a subpopulation of neurons in the ACC was activated by social stimuli and that silencing the social stimulus-responsive subpopulation of neurons in the ACC significantly impaired social interaction without affecting locomotor activity or anxiety-like behavior. Our current findings highlight the importance of the social stimulus-responsive subpopulation of neurons in the ACC for social behavior and the association between ACC dysfunction and impaired social behavior, which sheds light on therapeutic interventions for psychiatric conditions.

Changes in psychopharmacotherapy for patients with schizophrenia in a psychiatric institution in Japan: A 12-year prescription survey pre- and post-introduction of clozapine.

Psychopharmacotherapy for patients with schizophrenia in Japan has a long history of polypharmacy, which is rare worldwide but remains a critical problem. One reason for this is that clozapine was not available in Japan until 2009. We aimed to investigate the changes in psychopharmacotherapy in patients with schizophrenia over 12 years pre- and post-introduction of clozapine to clarify how psychopharmacotherapy for patients with schizophrenia has changed with the introduction of clozapine. We retrospectively collected data from the medical records of inpatients diagnosed with schizophrenia at the Okayama Psychiatric Medical Center. Chlorpromazine equivalent (CP-eq) decreased from 1276.6 mg/day in 2009 to 613.9 mg/day in 2020. The prescribed daily dose/defined daily dose (PDD/DDD) decreased from 3.0 in 2009 to 1.2 in 2020. The monotherapy rate increased from 24.4 % in 2009 to 74.6 % in 2020. Our institution began using clozapine in 2010, and the prescription rate for clozapine increased to 37.3 % in 2020. The prescription rate for more than three antipsychotics decreased from 27.8 % in 2009 to 0.8 % in 2020. The increase in clozapine prescription has contributed to an increased rate of antipsychotic monotherapy and a decreased rate of polypharmacy, promoting the optimization of schizophrenia medication. Clozapine therapy should be further promoted in Japan to reduce treatment-resistant schizophrenia due to polypharmacy as much as possible.

Guided versus unguided chatbot-delivered cognitive behavioral intervention for individuals with moderate-risk and problem gambling: A randomized controlled trial (GAMBOT2 study).

BACKGROUND: Internet-based interventions can be a promising option for individuals with problem gambling facing barriers to seeking help. This study aimed to directly compare the effects of therapist-guided Internet interventions with unguided ones on gambling-related behavior, cognition, and stage of change including help-seeking intention. METHODS: We conducted a participant-blinded randomized controlled trial of therapist-guided versus unguided groups with a 12-week follow-up. Both groups received self-help chatbot-delivered cognitive behavioral therapy. Additionally, at baseline and weeks 1, 2, 3, and 4, the guided group received personalized feedback messages from therapists based on their gambling diary and questionnaire responses. The unguided group received reminders of assessments from research assistants. The primary outcome was the change in scores on the Gambling Symptoms Assessment Scale (G-SAS) over 12 weeks. Secondary outcomes included the stage of change including help-seeking intention, money wagered, gambling frequency, and gambling-related cognitions. RESULTS: We included 139 participants with a mean Problem Gambling Severity Index total score of 14.6 and a mean G-SAS total score of 27.0 who sought information about gambling problems. Both groups demonstrated substantial decreases in their G-SAS scores from baseline to week 12 (-10.2, 95% CI: -7.67 to -12.7 for the guided group, and 11.7, 95% CI: -9.05 to -14.3 for the unguided group). However, we did not find a significant between-group difference (1.49, 95% CI: -2.20 to 5.17). Regarding the stage of change including help-seeking intention, there were also no between-group differences. CONCLUSIONS: Minimum therapist support did not have an additive effect on the self-help chatbot intervention on gambling symptoms, behavior, and the stage of change including help-seeking intention.

Mechanism of rate controllability of water-soluble bifunctional cyclooctadiynes through cation-anion interactions.

Click reactions are used for chemoselective functionalization in many research fields. Despite the utility of small, bioinert azide groups as a counterpart, applications of strain-promoted alkyne-azide cycloaddition (SPAAC) reactions for this purpose are still limited by slow reaction kinetics. Here, we report ion-pair-guided reaction rate enhancement by the use of water-soluble cyclooctadiynes (WS-CODYs) composed of bifunctional strained alkynes and polar side chains. Arrhenius plot analysis revealed that the rate enhancement by WS-CODYs is due to a kinetic salt effect between the polar substituents and the target azide. We demonstrate the utility of these compounds for rapid protein labelling and isoelectric point-dependent labelling.

Ion-Pair-Enhanced Double-Click Driven Cell Adhesion and Altered Expression of Related Genes.

Bio-orthogonal ligations that crosslink living cells with a substrate or other cells require high stability and rapid kinetics to maintain the nature of target cells. In this study, we report water-soluble cyclooctadiyne (WS-CODY) derivatives that undergo an ion-pair enhanced double-click reaction. The cationic side chain of WS-CODY accelerated the kinetics on the azide-modified cell surface due to proximity effect. Cationic WS-CODY was able to crosslink azide-modified, poorly adherent human lung cancer PC-9 cells not only to azide-grafted glass substrates but also to other cells within 5-30 min. We discovered that cell-substrate crosslinking induced the ITGA5 gene expression, whereas cell-cell crosslinking induced the CTNNA1 gene, according to the adhesion partner. Ion-pair-enhanced WS-CODY can be applied to a wide range of cells with established azide modifications and is expected to provide a powerful tool to regulate cell-substrate and cell-cell interactions.

Longitudinal changes in clozapine dose in patients with treatment-resistant schizophrenia: a 5-year retrospective cohort study.

This retrospective cohort study aimed to investigate the longitudinal changes in clozapine dose over a 5-year period in patients with treatment-resistant schizophrenia (TRS). Patients with TRS who were administered clozapine at a hospital between April 2012 and December 2016 and continued treatment with clozapine for at least 1 year were included. Clozapine doses were compared at the dose-fixation point, defined as when the same regimen of clozapine had been continued for 8 weeks or longer, and the post-dose-fixation phase, at 12, 36 and 60 months after clozapine initiation. We included 103 patients and found no significant differences in clozapine dose between the dose-fixation point and post-dose-fixation phase. Approximately half of the patients were categorized into an unchanged group at 12 months after clozapine initiation, whereas approximately 40% of patients were categorized into either the decreased or increased group at 60 months. Multivariable regression analysis revealed that the change in clozapine dose between the dose-fixation point and 60 months after clozapine initiation was negatively associated with clozapine dose at the dose-fixation point. On average, the clozapine dose was unchanged during long-term treatment in patients with TRS, although the dose was decreased or increased in approximately 40% of the patients.

Molecular brain (micro report) oxytocin ameliorates impaired social behavior in a mouse model of 3q29 deletion syndrome.

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by specific social symptoms, restricted interests, stereotyped repetitive behaviors, and delayed language development. The 3q29 microdeletion (3q29del), a recurrent copy number variant, confers a high risk for ASD and schizophrenia, and serves as an important pathological model for investigating the molecular pathogenesis of a large number of neurodevelopmental and psychiatric conditions. Recently, mouse models carrying a deletion of the chromosomal region corresponding to the human 3q29 region (Df/+ mice) were generated and demonstrated neurodevelopmental and psychiatric conditions associated behavioral abnormalities, pointing to the relevance of Df/+ mice as a model for these conditions with high construct and face validity. Currently, the molecular pathogenesis of these behavioral phenotypes in Df/+ mice remains unclear. The oxytocin (OXT) system plays a central role in social behavior across species and has a potential role in ASD. In this study, to elucidate the molecular mechanisms behind impaired social behavior in Df/+ mice, we investigated the possible involvement of OXT signaling in impaired social behavior in Df/+ mice. We demonstrated that OXT administration restored the impaired social behavior in Df/+ mice. We also demonstrated that the number of OXT-positive cells in the paraventricular nucleus (PVN) was significantly lower in Df/+ mice than in wild-type (WT) littermates. Consistent with this, the level of OXT peptide in the cerebral cortex of Df/+ mice was lower than in WT littermates. Our study may provide important insights into the molecular pathophysiological basis of neurodevelopmental and psychiatric conditions, including ASD.

Course of insight, depression and suicidality in inpatients with first-episode schizophrenia who received group psychoeducation.

AIM: We aimed to investigate whether gaining insight through psychoeducation for first-episode schizophrenia is associated with increased suicidality. METHODS: We conducted a secondary analysis of a prospective cohort study that included inpatients with first-episode schizophrenia who attended a group psychoeducation program during their admission. The group psychoeducation program consisted of four weekly sessions provided by a multidisciplinary team. The primary outcome was the correlation between changes in insight and suicidality. We also examined whether change in insight was associated with changes in hopelessness and depression. We measured insight using the Birchwood Insight Scale. Suicidality, hopelessness and depression were measured using the Calgary Depression Rating Scale for Schizophrenia. RESULTS: A total of 125 people participated in the educational program. The Spearman's correlation coefficient between changes in insight and suicidality was -0.14 (95% confidence interval, -0.31 to 0.04; p = .12). Similarly, gain in insight did not significantly correlate with change in depression (0.01, 95% confidence interval, -0.17 to 0.18; p = .93) and change in hopelessness (0.01, 95% confidence interval, -0.16 to 0.19; p = .88). CONCLUSIONS: We observed almost no association between gaining insight and suicidality after a group psychoeducation program in inpatients with first-episode schizophrenia.

Clozapine Once-Daily Versus Divided Dosing Regimen: A Cross-sectional Study in Japan.

OBJECTIVE: Clozapine is generally recommended to be prescribed in a divided dosing regimen based on its relatively short plasma half-life. However, there has been little evidence to support the superiority of divided dosing of clozapine over once-daily dosing. To our knowledge, there have been no studies examining differences in actual plasma concentrations or adverse effects between the 2 dosing strategies of clozapine. We aimed to compare actual plasma concentrations of clozapine between once-daily and divided dosing regimens, and to examine the relationships of these regimens with psychiatric symptoms and adverse effects of clozapine. METHODS: We analyzed data from 108 participants of a previous study conducted in 2 hospitals in Japan. A population pharmacokinetic model was used to estimate the peak and trough plasma concentrations of clozapine based on actual plasma concentrations. We evaluated psychiatric symptoms with the Brief Evaluation of Psychosis Symptom Domains and adverse effects of clozapine with the Glasgow Antipsychotic Side-effects Scale for Clozapine. RESULTS: The estimated peak and trough plasma concentrations of clozapine did not differ significantly between once-daily and divided dosing regimens. There were no significant differences in psychiatric symptoms except for depression/anxiety or subjective adverse effects of clozapine between the 2 dosing strategies. CONCLUSIONS: Our findings tentatively support the feasibility and clinical utility of once-daily dosing of clozapine in clinical practice. Further studies are needed to replicate these findings and determine causality between dosing strategies and clinical outcomes.

PACAP-PAC1 Signaling Regulates Serotonin 2A Receptor Internalization.

Mice lacking pituitary adenylate cyclase-activating polypeptide (PACAP) display psychomotor abnormalities, most of which are ameliorated by atypical antipsychotics with serotonin (5-HT) 2A receptor (5-HT2A) antagonism. Heterozygous Pacap mutant mice show a significantly higher hallucinogenic response than wild-type mice to a 5-HT2A agonist. Endogenous PACAP may, therefore, affect 5-HT2A signaling; however, the underlying neurobiological mechanism for this remains unclear. Here, we examined whether PACAP modulates 5-HT2A signaling by addressing cellular protein localization. PACAP induced an increase in internalization of 5-HT2A but not 5-HT1A, 5-HT2C, dopamine D2 receptors or metabotropic glutamate receptor 2 in HEK293T cells. This PACAP action was inhibited by protein kinase C inhibitors, ß-arrestin2 silencing, the PACAP receptor PAC1 antagonist PACAP6-38, and PAC1 silencing. In addition, the levels of endogenous 5-HT2A were decreased on the cell surface of primary cultured cortical neurons after PACAP stimulation and were increased in frontal cortex cell membranes of Pacap-/- mice. Finally, intracerebroventricular PACAP administration suppressed 5-HT2A agonist-induced head twitch responses in mice. These results suggest that PACAP-PAC1 signaling increases 5-HT2A internalization resulting in attenuation of 5-HT2A-mediated signaling, although further study is necessary to determine the relationship between behavioral abnormalities in Pacap-/- mice and PACAP-induced 5-HT2A internalization.

Multiple alterations in glutamatergic transmission and dopamine D2 receptor splicing in induced pluripotent stem cell-derived neurons from patients with familial schizophrenia.

An increasing body of evidence suggests that impaired synapse development and function are associated with schizophrenia; however, the underlying molecular pathophysiological mechanism of the disease remains largely unclear. We conducted a family-based study combined with molecular and cellular analysis using induced pluripotent stem cell (iPSC) technology. We generated iPSCs from patients with familial schizophrenia, differentiated these cells into neurons, and investigated the molecular and cellular phenotypes of the patient's neurons. We identified multiple altered synaptic functions, including increased glutamatergic synaptic transmission, higher synaptic density, and altered splicing of dopamine D2 receptor mRNA in iPSC-derived neurons from patients. We also identified patients' specific genetic mutations using whole-exome sequencing. Our findings support the notion that altered synaptic function may underlie the molecular and cellular pathophysiology of schizophrenia, and that multiple genetic factors cooperatively contribute to the development of schizophrenia.

Comprehensive assessment of exposure to clozapine in association with side effects among patients with treatment-resistant schizophrenia: a population pharmacokinetic study.

BACKGROUND: There have been scarce data on the distribution of clozapine concentrations in comparison with the recommended range (350-600 ng/ml) or their relationship with side effects among patients with treatment-resistant schizophrenia. Furthermore, no studies have assessed the association between side effects and overall exposure to the drug by calculating the 24-h area-under-curve (AUC). METHODS: In- and outpatients with schizophrenia or schizoaffective disorder (ICD-10) who were receiving a stable dose of clozapine for ⩾2 weeks were included. Side effects were assessed using the Glasgow antipsychotic side-effects scale for clozapine (GASS-C). Using two collected plasma samples, plasma clozapine and norclozapine concentrations at peak and trough and their 24-h AUC were estimated using population pharmacokinetic models. RESULTS: A total of 108 patients completed the study (mean ± SD age, 43.0 ± 10.1 years; clozapine dose, 357.5 ± 136.9 mg/day); 33 patients (30.6%) showed estimated trough concentrations of clozapine within the recommended range (350-600 ng/ml) whereas the concentrations were higher and lower than this range among 37 (43.5%) and 28 (25.9%) patients (%), respectively. There were no significant correlations between estimated peak or trough concentrations or 24-h AUC of both clozapine or norclozapine, and GASS-C total or individual scores. No significant differences were found between GASS-C total or individual item scores between the patients with estimated trough concentrations of clozapine of >600 ng/ml and the other subjects. CONCLUSION: The results suggest that clozapine or norclozapine concentrations are not linked directly to the extent of side effects experienced in clozapine-treated patients with treatment-resistant schizophrenia while the cross-sectional study design limits the interpretation of any causal relationships. These findings indicate that side effects associated with clozapine may occur at any dose or concentration.

Risk factors for clozapine-induced central nervous system abnormalities in Japanese patients with treatment-resistant schizophrenia.

The purpose of this study was to assess the risk factors for clozapine-induced central nervous system (CNS) abnormalities (i.e., electroencephalogram [EEG] abnormalities, myoclonus, and seizures). We retrospectively analyzed data from 106 patients with schizophrenia who received clozapine treatment through our hospital. A review of the EEG recordings showed that 71 of these patients (67.0 %) developed CNS abnormalities after initiating clozapine treatment. EEG abnormalities, myoclonus, and seizures occurred in 53.8 %, 38.7 %, and 8.5 % of the patients, respectively. Multivariate logistic regression analysis showed that the risk factors for clozapine-induced CNS abnormalities were concomitant lithium usage (odds ratio, 4.560; 95 % confidence interval, 1.750-11.900) and shorter illness durations before clozapine initiation (odds ratio, 0.796; 95 % confidence interval, 0.649-0.976). However, plasma clozapine levels and the usage of antiepileptics did not exhibit associations with the risks of CNS abnormalities. Clinicians should monitor their patients for incident CNS abnormalities when administering lithium in combination with clozapine regardless of plasma clozapine levels or the usage of antiepileptics. This is especially true for patients with short illness durations.

Intranasal oxytocin administration ameliorates social behavioral deficits in a POGZWT/Q1038R mouse model of autism spectrum disorder.

Autism spectrum disorder (ASD) is a highly prevalent neurodevelopmental disorder characterized by core symptoms of impaired social behavior and communication. Recent studies have suggested that the oxytocin system, which regulates social behavior in mammals, is potentially involved in ASD. Mouse models of ASD provide a useful system for understanding the associations between an impaired oxytocin system and social behavior deficits. However, limited studies have shown the involvement of the oxytocin system in the behavioral phenotypes in mouse models of ASD. We have previously demonstrated that a mouse model that carries the ASD patient-derived de novo mutation in the pogo transposable element derived with zinc finger domain (POGZWT/Q1038R mice), showed ASD-like social behavioral deficits. Here, we have explored whether oxytocin (OXT) administration improves impaired social behavior in POGZWT/Q1038R mice and found that intranasal oxytocin administration effectively restored the impaired social behavior in POGZWT/Q1038R mice. We also found that the expression level of the oxytocin receptor gene (OXTR) was low in POGZWT/Q1038R mice. However, we did not detect significant changes in the number of OXT-expressing neurons between the paraventricular nucleus of POGZWT/Q1038R mice and that of WT mice. A chromatin immunoprecipitation assay revealed that POGZ binds to the promoter region of OXTR and is involved in the transcriptional regulation of OXTR. In summary, our study demonstrate that the pathogenic mutation in the POGZ, a high-confidence ASD gene, impairs the oxytocin system and social behavior in mice, providing insights into the development of oxytocin-based therapeutics for ASD.

Longitudinal changes in antipsychotic dose in patients treated with long-acting injectable second-generation antipsychotics.

Only a few studies have investigated changes in the dose of long-acting injectable second-generation antipsychotics (LAI-SGAs) over the long term in the maintenance treatment of schizophrenia. In this retrospective cohort study, we examined longitudinal changes in antipsychotic dose over a 3-year period in patients with schizophrenia who had been taking LAI-SGAs for at least 1 year. We compared the total daily chlorpromazine equivalent dose of antipsychotics at 12, 24 and 36 months with the baseline dose at 3 months after initiation of LAI-SGAs. We also performed multiple regression analysis to explore factors associated with change in total daily dose 12 months after treatment initiation. A total of 154 patients fulfilled the inclusion criteria. There was no significant difference in total daily antipsychotic dose between 3 months and 12, 24 or 36 months after treatment initiation. Total daily dose was increased in 43 (27.9%), 31 (34.8%) and 22 patients (36.7%) at 12, 24 and 36 months, respectively. Age and total antipsychotic dose at 3 months were significantly negatively associated with change in total daily dose. Antipsychotic dose was basically unchanged during long-term treatment in patients treated with LAI-SGAs in the maintenance phase, although there was an increase in some patients.

The relationship between plasma clozapine concentration and clinical outcome: a cross-sectional study.

OBJECTIVE: There is no report that statistically evaluates the therapeutic reference (350-600 ng/ml) and adverse drug reaction (ADR) range (>1000 ng/ml) of clozapine (CLZ) recommended by the Arbeitsgemeinschaft für Neuropsychopharmakologie und Pharmakopsychiatrie (AGNP) consensus guidelines in an isolated and large sampling study. METHODS: We administered CLZ to 131 Japanese patients with treatment-resistant schizophrenia in a multicenter cross-sectional study. Plasma CLZ concentrations were assayed by high-performance liquid chromatography using trough sampling. The Brief Psychiatric Rating Scale (BPRS) and severe dose-dependent ADR (sedation, myoclonus, and seizures) were analyzed statistically after adjusting for possible confounders. RESULTS: The daily CLZ dosage showed a moderately positive relationship with the plasma concentration (r = 0.49, p < 0.001). Every 100 ng/ml increase in plasma CLZ concentration improved the total BPRS score 1.95% (95% CI: 0.89-3.01, p < 0.001) and the odds ratio (OR) 1.38 (95% CI: 1.14-1.66, p = 0.001) for BPRS response. Compared with concentrations below 350 ng/ml CLZ, 350-600 ng/ml (11.12%; 95% CI: 2.52-19.72, p = 0.012) and 600-1000 ng/ml (11.05%; 95% CI: 2.40-19.71, p = 0.013) showed significant improvement in the total BPRS score. Dosages above 1000 ng/ml showed greater improvement (25.36%; 95% CI: 13.08-37.64, p < 0.001) of the total BPRS score but more severe ADRs than dosages below 1000 ng/ml (OR: 31.72; 95% CI: 1.04-968.81, p = 0.048). CONCLUSION: The AGNP therapeutic reference range (350-600 ng/ml) is useful, and a dose above 1000 ng/ml is potentially more effective but carries the risk of severe ADRs in the central nervous system.

Reliability of the Glasgow Antipsychotic Side-effects Scale for Clozapine Japanese version (GASS-C-J).

The purpose of this study was to develop the Glasgow Antipsychotic Side effects Scale for Clozapine Japanese version (GASS-C-J) and examine its reliability to assess clozapine-related side effects. We developed the GASS-C-J using forward and backward translation. Semantic equivalence of the GASS-C-J to the GASS-C was confirmed by the original author. We then administered the GASS-C-J twice to 109 patients on clozapine treatment at two psychiatric hospitals in Japan. We assessed the internal consistency and test-retest reliability of the GASS-C-J using Cronbach's alpha and weighted kappa coefficient, respectively. We also examined if discrepancies in each GASS-C-J item score between the first and second rating were correlated with items of the Brief Evaluation of Psychosis Symptom Domains (BE-PSD). The Cronbach's alpha coefficient of the GASS-C-J at the first and second rating was 0.78 (95% CI: 0.72 to 0.84) and 0.82 (95% CI: 0.76 to 0.88), respectively. The weighted kappa coefficient of individual and total GASS-C-J item scores ranged from 0.45 to 0.88. Some symptom domains were correlated with discrepancies in specific items of the GASS-C-J: psychotic symptoms and nausea/vomiting (rs = 0.27), thirst (rs = 0.31), and appetite/weight gain (rs = 0.27); disorganized thinking and urinary incontinence (rs = 0.26); depression/anxiety and myoclonus (rs = 0.25), hypersalivation (rs = -0.27), and blurred vision (rs = -0.22). These findings demonstrate that the GASS-C-J can be used in clinical and research settings as a reliable scale to assess clozapine-related side effects.