Dose equivalents for second-generation antipsychotics: the minimum effective dose method

Quantifying abnormal emotion processing: A novel computational assessment method and application in schizophrenia

Abnormal emotion processing is a core feature of schizophrenia spectrum disorders (SSDs) that encompasses multiple operations. While deficits in some areas have been well-characterized, we understand less about abnormalities in the emotion processing that happens through language, which is highly relevant for social life. Here, we introduce a novel method using deep learning to estimate emotion processing rapidly from spoken language, testing this approach in male-identified patients with SSDs (n = 37) and healthy controls (n = 51). Using free responses to evocative stimuli, we derived a measure of appropriateness, or "emotional alignment" (EA). We examined psychometric characteristics of EA and its sensitivity to a single-dose challenge of oxytocin, a neuropeptide shown to enhance the salience of socioemotional information in SSDs. Patients showed impaired EA relative to controls, and impairment correlated with poorer social cognitive skill and more severe motivation and pleasure deficits. Adding EA to a logistic regression model with language-based measures of formal thought disorder (FTD) improved classification of patients versus controls. Lastly, oxytocin administration improved EA but not FTD among patients. While additional validation work is needed, these initial results suggest that an automated assay using spoken language may be a promising approach to assess emotion processing in SSDs.

Excessive left anterior hippocampal and caudate activation in schizophrenia underlie cognitive underperformance in a virtual navigation task

We used a virtual navigation paradigm in a city environment to assess neuroanatomical correlates of cognitive deficits in schizophrenia spectrum disorders (SSD). We studied a total of N = 36 subjects: 18 with SSD and 18 matched unaffected controls. Participants completed 10 rapid, single-trial navigation tasks within the virtual city while undergoing functional magnetic resonance imaging (fMRI). All trials tested ability to find different targets seen earlier, during the passive viewing of a path around different city blocks. SSD patients had difficulty finding previously-encountered targets, were less likely to find novel shortcuts to targets, and more likely to attempt retracing of the path observed during passive viewing. Based on a priori region-of-interest analyses, SSD participants had hyperactivation of the left hippocampus when passively viewing turns, hyperactivation of the left caudate when finding targets, and hypoactivation of a focal area of the dorsolateral prefrontal cortex when targets were initially shown during passive viewing. We propose that these brain-behaviour relations may bias or reinforce stimulus-response navigation approaches in SSD and underlie impaired performance when allocentric spatial memory is required, such as when forming efficient shortcuts. This pattern may extend to more general cognitive impairments in SSD that could be used to design remediation strategies.

Investigating cortical excitability and inhibition in patients with schizophrenia: A TMS-EEG study

BACKGROUND

Transcranial magnetic stimulation (TMS) combined with electromyography (EMG) has widely been used as a non-invasive brain stimulation tool to assess excitation/inhibition (E/I) balance. E/I imbalance is a putative mechanism underlying symptoms in patients with schizophrenia. Combined TMS-electroencephalography (TMS-EEG) provides a detailed examination of cortical excitability to assess the pathophysiology of schizophrenia. This study aimed to investigate differences in TMS-evoked potentials (TEPs), TMS-related spectral perturbations (TRSP) and intertrial coherence (ITC) between patients with schizophrenia and healthy controls.

MATERIALS AND METHODS

TMS was applied over the motor cortex during EEG recording. Differences in TEPs, TRSP and ITC between the patient and healthy subjects were analysed for all electrodes at each time point, by applying multiple independent sample t-tests with a cluster-based permutation analysis to correct for multiple comparisons.

RESULTS

Patients demonstrated significantly reduced amplitudes of early and late TEP components compared to healthy controls. Patients also showed a significant reduction of early delta (50-160 ms) and theta TRSP (30-250ms),followed by a reduction in alpha and beta suppression (220-560 ms; 190-420 ms). Patients showed a reduction of both early (50-110 ms) gamma increase and later (180-230 ms) gamma suppression. Finally, the ITC was significantly lower in patients in the alpha band, from 30 to 260 ms.

CONCLUSION

Our findings support the putative role of impaired GABA-receptor mediated inhibition in schizophrenia impacting excitatory neurotransmission. Further studies can usefully elucidate mechanisms underlying specific symptoms clusters using TMS-EEG biometrics.

Identification and treatment of individuals with childhood-onset and early-onset schizophrenia

Approximately 8 % of patients with schizophrenia are diagnosed before age 18, and 18 % experience their first symptoms before age 18. This narrative review explores the management of patients with early-onset schizophrenia (EOS) and childhood-onset schizophrenia (COS) from diagnosis to their transition to adult care settings. Early diagnosis of schizophrenia in children and adolescents is essential for improving outcomes, but delays are common due to overlapping of symptoms with developmental phenomena and other psychiatric conditions, including substance use, and lack of clinicians' awareness. Once diagnosed, antipsychotic treatment is key, with specific second-generation agents generally being preferred due to better tolerability and their broader efficacy evidence-base in youth. Dosing should be carefully individualized, considering age-related differences in drug metabolism and side effect liability. Clinicians must be vigilant in detecting early non-response and consider switching or dose escalation when appropriate. Since early age of illness onset is a consistent risk factor for treatment-resistant schizophrenia (TRS), clinicians need to be competent in diagnosing TRS and using clozapine. Since COS and EOS are associated with cognitive deficits and impaired functioning, psychosocial interventions should be considered to improve overall functioning and quality of life. Good long-term outcomes depend on continuous treatment engagement, and successful transitioning from pediatric to adult care requires careful planning, early preparation, and collaboration between pediatric and adult clinicians. Targeting functional outcomes and quality of life in addition to symptom remission can improve overall patient well-being. Comprehensive evaluations, age-specific assessments, and targeted interventions are needed to address the unique challenges of EOS and COS.

Automated linguistic analysis in speech samples of Turkish-speaking patients with schizophrenia-spectrum disorders

Modern natural language processing (NLP) methods provide ways to objectively quantify language disturbances for potential use in diagnostic classification. We performed computerized language analysis in speech samples of 82 Turkish-speaking subjects, including 44 patients with schizophrenia spectrum disorders (SSD) and 38 healthy controls (HC). Exploratory analysis of speech samples involved 16 sentence-level semantic similarity features using SBERT (Sentence Bidirectional Encoder Representation from Text) as well as 8 generic and 8 part-of-speech (POS) features. The random forest classifier using SBERT-derived semantic similarity features achieved a mean accuracy of 85.6 % for the classification of SSD and HC. When semantic similarity features were combined with generic and POS features, the classifier's mean accuracy reached to 86.8 %. Our analysis reflected increased sentence-level semantic similarity scores in SSD. Generic and POS analyses revealed an increase in the use of verbs, proper nouns and pronouns in SSD while our results showed a decrease in the utilization of conjunctions, determiners, and both average and maximum sentence length in SSD compared to HC. Quantitative language features were correlated with the expressive deficit domain of BNSS (Brief Negative Symptom Scale) as well as with the duration of illness. These findings from Turkish-speaking interviews contribute to the growing evidence-based NLP-derived assessments in non-English-speaking patients.

Single-arm meta-analysis of drug response in placebo-controlled versus active-controlled antipsychotic drug trials in schizophrenia

Antipsychotic drug efficacy may vary in placebo-controlled and active-controlled trials. The study aims to investigate the performance of antipsychotics in these two different study designs using single-arm meta-analysis. We included randomized controlled trials (RCTs) comparing second-generation antipsychotics with placebo or other antipsychotics from our previous systematic reviews and updated the results with the search on Cochrane Schizophrenia Group register until March 06, 2022. The outcomes were the differences in the change of overall, positive and negative symptoms of schizophrenia, and the difference in study discontinuation between placebo-controlled and head-to-head trials. Random-effects single-arm meta-analysis and subgroup test were conducted to examine the differences in each outcome. A total of 208 RCTs (n = 42,159) were included in the analysis. Of these, 85 trials with 17,056 participants were placebo-controlled, while the remaining were head-to-head trials. Antipsychotics in head-to-head trials demonstrated a significantly greater improvement in overall symptoms (MC -23.58; 95 % CI -25.33, -21.83) compared to antipsychotics in placebo-controlled trials (MC -16.74; 95 % CI -17.80, -15.69; p < 0.0001). Similar findings were observed for positive symptoms, negative symptoms, study discontinuation and sensitivity analyses. Notably, when assessing antipsychotics individually, the same antipsychotic consistently demonstrated superior performance in head-to-head trials compared to placebo-controlled trials. In conclusion, antipsychotics in head-to-head trials presented a considerable efficacy superiority compared to those in placebo-controlled trials. Moreover, the efficacy of the same antipsychotics varied depending on the study design. Future trials should carefully consider the methodology and employ strategies to mitigate the potential for overestimation or underestimation of treatment efficacy.

Associations of altered leukocyte DDR1 promoter methylation and childhood trauma with bipolar disorder and suicidal behavior in euthymic patients

Altered DNA methylation (DNAm) patterns of discoidin domain receptor 1 (DDR1) have been found in the blood and brain of patients with schizophrenia (SCZ) and the brain of patients with bipolar disorder (BD). Childhood trauma (CT) is associated with changes in DNAm that in turn are related to suicidal behavior (SB) in patients with several psychiatric disorders. Here, using MassARRAY® technology, we studied 128 patients diagnosed with BD in remission and 141 healthy controls (HCs) to compare leukocyte DDR1 promoter DNAm patterns between patients and HCs and between patients with and without SB. Additionally, we investigated whether CT was associated with DDR1 DNAm and mediated SB. We found hypermethylation at DDR1 cg19215110 and cg23953820 sites and hypomethylation at cg14279856 and cg03270204 sites in patients with BD compared to HCs. Logistic regression models showed that hypermethylation of DDR1 cg23953820 but not cg19215110 and CT were risk factors for BD, while cg14279856 and cg03270204 hypomethylation were protective factors. In patients, CT was a risk factor for SB, but DDR1 DNAm, although associated with CT, did not mediate the association of CT with SB. This is the first study demonstrating altered leukocyte DDR1 promoter DNAm in euthymic patients with BD. We conclude that altered DDR1 DNAm may be related to immune and inflammatory mechanisms and could be a potential blood biomarker for the diagnosis and stratification of psychiatric patients.

Histamine-3 Receptor Availability and Glutamate Levels in the Brain: A PET-1H-MRS Study of Patients With Schizophrenia and Healthy Controls

BACKGROUND

The histamine-3 receptor (H3R) may have a role in cognitive processes through its action as a presynaptic heteroreceptor inhibiting the release of glutamate in the brain. To explore this, we examined anterior cingulate cortex (ACC) and striatum H3R availability in patients with schizophrenia and characterized their relationships with glutamate levels in corresponding brain regions.

METHODS

We employed a cross-sectional study, recruiting 12 patients with schizophrenia and 12 healthy volunteers. Participants underwent positron emission tomography using the H3R-specific radio ligand [11C]MK-8278, followed by proton magnetic resonance spectroscopy to measure glutamate levels, recorded as Glu and Glx. Based on existing literature, the ACC and striatum were selected as regions of interest.

RESULTS

We found significant inverse relationships between tracer uptake and Glu (r = -0.66, P = .02) and Glx (r = -0.62, P = .04) levels in the ACC of patients, which were absent in healthy volunteers (Glu: r = -0.19, P = .56, Glx: r = 0.10, P = .75). We also found a significant difference in striatal (F1,20 = 6.00, P = .02) and ACC (F1,19 = 4.75, P = .04) Glx levels between groups.

CONCLUSIONS

These results provide evidence of a regionally specific relationship between H3Rs and glutamate levels, which builds on existing preclinical literature. Our findings add to a growing literature indicating H3Rs may be a promising treatment target in schizophrenia, particularly for cognitive impairment, which has been associated with altered glutamate signaling.

Altered Perception of Environmental Volatility During Social Learning in Emerging Psychosis

Paranoid delusions or unfounded beliefs that others intend to deliberately cause harm are a frequent and burdensome symptom in early psychosis, but their emergence and consolidation still remains opaque. Recent theories suggest that overly precise prediction errors lead to an unstable model of the world providing a breeding ground for delusions. Here, we employ a Bayesian approach to test for such an unstable model of the world and investigate the computational mechanisms underlying emerging paranoia. We modelled behaviour of 18 first-episode psychosis patients (FEP), 19 individuals at clinical high risk for psychosis (CHR-P), and 19 healthy controls (HC) during an advice-taking task designed to probe learning about others' changing intentions. We formulated competing hypotheses comparing the standard Hierarchical Gaussian Filter (HGF), a Bayesian belief updating scheme, with a mean-reverting HGF to model an altered perception of volatility. There was a significant group-by-volatility interaction on advice-taking suggesting that CHR-P and FEP displayed reduced adaptability to environmental volatility. Model comparison favored the standard HGF in HC, but the mean-reverting HGF in CHR-P and FEP in line with perceiving increased volatility, although model attributions in CHR-P were heterogeneous. We observed correlations between perceiving increased volatility and positive symptoms generally as well as with frequency of paranoid delusions specifically. Our results suggest that FEP are characterised by a different computational mechanism - perceiving the environment as increasingly volatile - in line with Bayesian accounts of psychosis. This approach may prove useful to investigate heterogeneity in CHR-P and identify vulnerability for transition to psychosis.

Smaller anterior hippocampal subfields in the early stage of psychosis

Hippocampal volume is smaller in schizophrenia, but it is unclear when in the illness the changes appear and whether specific regions (anterior, posterior) and subfields (CA1, CA2/3, dentate gyrus, subiculum) are affected. Here, we used a high-resolution T2-weighted sequence specialized for imaging hippocampal subfields to test the hypothesis that anterior CA1 volume is lower in early psychosis. We measured subfield volumes across hippocampal regions in a group of 90 individuals in the early stage of a non-affective psychotic disorder and 70 demographically similar healthy individuals. We observed smaller volume in the anterior CA1 and dentate gyrus subfields in the early psychosis group. Our findings support models that implicate anterior CA1 and dentate gyrus subfield deficits in the mechanism of psychosis.

[Therapy of mental disorders in patients with hematological malignancies]

OBJECTIVE

To assess the possibilities of therapy with minimal effective doses (MED) of psychotropic drugs for mental disorders (MD) that manifest during the treatment of hematological malignancies (HM).

MATERIAL AND METHODS

A prospective study was conducted at the National Medical Research Center for Hematology of the Russian Ministry of Health (Moscow), which included 204 (39.4%) men and 314 (60.6%) women (518 patients in total), aged 17 to 83 years (median 45 years), with various HM, in which the manifestation of MD occurred during the treatment of the underlying disease. To minimize the side-effects of psychotropic drugs and given the relatively mild level of MD, psychopharmacotherapy of patients was carried out mainly at MED. The severity of MD, manifested in patients, was assessed by the illness severity scale of the Clinical Global Impression (CGI) scale, and the effectiveness of the treatment was assessed by the improvement scale (CGI-I).

RESULTS

Mainly mild (188, 36%) and moderately pronounced (270, 52%) MD were noted in patients with HM during the treatment of the underlying disease. Severe psychopathological disorders (60, 12%) were observed much less often. Because of psychopharmacotherapy with MED, patients experienced a very significant (97, 19%) and significant improvement (354, 68%) of their mental state, less often the improvement was regarded as minimal (67, 13%). Therefore, almost all patients showed a stable relief of MD; in 87% (95% CI 84-90) of patients, this improvement was significant.

CONCLUSION

The tactics of treatment MD that manifest in patients with HM with MED of psychotropic drugs turned out to be therapeutically effective according to the results of the assessment on CGI scales.

The association of childhood trauma with depressive and negative symptoms in recent onset psychosis: a sex-specific analysis

BACKGROUND

Childhood trauma may impact the course of schizophrenia spectrum disorders (SSD), specifically in relation to the increased severity of depressive or negative symptoms. The type and impact of trauma may differ between sexes. In a large sample of recent-onset patients, we investigated the associations of depressive and negative symptoms with childhood trauma and whether these are sex-specific.

METHODS

A total of 187 first-episode psychosis patients in remission (Handling Antipsychotic Medication: Long-term Evaluation of Targeted Treatment study) and 115 recent-onset SSD patients (Simvastatin study) were included in this cross-sectional study (men: n = 218; women: n = 84). Total trauma score and trauma subtypes were assessed using the Childhood Trauma Questionnaire Short Form; depressive and negative symptoms were rated using the Positive And Negative Symptoms Scale. Sex-specific regression analyses were performed.

RESULTS

Women reported higher rates of sexual abuse than men (23.5% v. 7.8%). Depressive symptoms were associated with total trauma scores and emotional abuse ratings in men (β: 0.219-0.295; p ≤ 0.001). In women, depressive symptoms were associated with sexual abuse ratings (β: 0.271; p = 0.011). Negative symptoms were associated with total trauma score and emotional neglect ratings in men (β: 0.166-0.232; p ≤ 0.001). Negative symptoms in women were not linked to childhood trauma, potentially due to lack of statistical power.

CONCLUSIONS

Depressive symptom severity was associated with different types of trauma in men and women with recent-onset SSD. Specifically, in women, depressive symptom severity was associated with childhood sexual abuse, which was reported three times as often as in men. Our results emphasize the importance of sex-specific analyses in SSD research.

Deconstructing the genetic architecture of treatment-resistant schizophrenia in East Asian ancestry

BACKGROUND

Treatment-resistant schizophrenia (TRS) affects a substantial proportion of patients who do not respond adequately to antipsychotic medications, yet the underlying biological mechanism remains poorly understood. This study investigates the link between the genetic predisposition to schizophrenia and TRS.

METHODS

857 individuals diagnosed with schizophrenia were divided into TRS (n = 142) and non-TRS (n = 715) based on well-defined TRS criteria. Polygenic risk scores (PRS) were calculated using schizophrenia genome-wide association summary statistics from East-Asian and European ancestry populations. PRS was estimated using both P-value thresholding and Bayesian framework methods. Logistic regression analyses were performed to differentiate between TRS and non-TRS individuals.

RESULTS

The schizophrenia PRS derived from the East-Asian training dataset effectively distinguished between TRS and non-TRS individuals (R2 = 0.029, p = 4.86 ×10-5, pT = 0.1, OR = 1.52, 95% CI = 1.242-1.861), with higher PRS values observed in the TRS group. Similar PRS analysis was conducted based on the European ancestry GWAS summary statistics, but we found superior prediction based on the East-Asian ancestry discovery data.

CONCLUSION

This study reveals an association between common risk variants for schizophrenia and TRS status, suggesting that the genetic burden of schizophrenia may partly contribute to treatment resistance in individuals with schizophrenia. These findings propose the potential use of genetic risk factors for early TRS identification and timely access to clozapine. However, the ancestral background of the discovery sample is crucial for successfully implementing PRS in clinical settings.

Exploring the link between functional connectivity of ventral tegmental area and physical fitness in schizophrenia and healthy controls

Decreased physical fitness and being overweight are highly prevalent in schizophrenia, represent a major risk factor for comorbid cardio-vascular diseases and decrease the life expectancy of the patients. Thus, it is important to understand the underlying mechanisms that link psychopathology and weight gain. We hypothesize that the dopaminergic reward system plays an important role in this. We analyzed the seed-based functional connectivity (FC) of the ventral tegmental area (VTA) in a group of schizophrenic patients (n=32) and age-, as well as gender-, matched healthy controls (n=27). We then correlated the resting-state results with physical fitness parameters, obtained in a fitness test, and psychopathology. The FC analysis revealed decreased functional connections between the VTA and the anterior cingulate cortex (ACC), as well as the dorsolateral prefrontal cortex, which negatively correlated with psychopathology, and increased FC between the VTA and the middle temporal gyrus in patients compared to healthy controls, which positively correlated with psychopathology. The decreased FC between the VTA and the ACC of the patient group further positively correlated with total body fat (p = .018, FDR-corr.) and negatively correlated with the overall physical fitness (p = .022). This study indicates a link between decreased physical fitness and higher body fat with functional dysconnectivity between the VTA and the ACC. These findings demonstrate that a dysregulated reward system might also be involved in comorbidities and could pave the way for future lifestyle therapy interventions.

Poverty and inequality in real-world schizophrenia: a national study

Background

Schizophrenia has high socioeconomic impact among severe psychiatric disorders.

Aims

To explore clinician-reported and patient-reported inequities between patients under the poverty threshold vs. the others.

Method

916 patients consecutively recruited in 10 national centers received a comprehensive standardized evaluation of illness severity, addictions and patient-reported outcomes.

Results

739 (80.7%) of the patients were classified in the poverty group. This group had poorer objective illness outcomes (lower positive, negative, cognitive, excitement/aggressive and self-neglect symptoms and lifetime history of planned suicide) in multivariate analyses. While they had similar access to treatments and psychotherapy, they had lower access to socially useful activities, couple's life, housing and parenthood. They had also more disturbed metabolic parameters. On the contrary, the poverty group reported better self-esteem. No significant difference for depression, risky health behavior including addictions and sedentary behavior was found.

Interpretation

The equity in access to care is attributed to the French social system. However, mental and physical health remain poorer in these patients, and they still experience poor access to social roles independently of illness severity and despite healthcare interventions. These patients may have paradoxically better self-esteem due to decreased contact with society and therefore lower stigma exposure (especially at work). Schizophrenia presents itself as a distinct impoverished population concerning health-related outcomes and social integration, warranting focus in public health initiatives and improved treatment, including tailored interventions, collaborative care models, accessible mental health services, housing support, vocational training and employment support, community integration, education and awareness, research and data collection, culturally competent approaches, and long-term support.

Once-daily versus divided dosing regimens of clozapine: A cross-sectional study in Singapore

INTRODUCTION

Clozapine is recognized as the gold standard medication for treatment-resistant schizophrenia. Despite the general recommendation of administering in a divided dosing regimen, clozapine is often prescribed once daily at night in clinical practice. This study aims to compare patient characteristics, psychiatric symptoms, side effects, and plasma concentration of clozapine between once-daily dosing and divided dosing regimens.

METHODS

This cross-sectional study included 159 participants with treatment-resistant schizophrenia or schizoaffective disorder. Participant's demographic information, anthropometric data, and medical history were collected. Their psychiatric symptoms, cognition, functioning, and side effects were evaluated.

RESULTS

Once-daily dosing regimen was associated with younger age and competitive employment. Lower clinical symptom severity, better functioning and cognitive performance were observed in the once-daily dosing group. Lower daily dose of clozapine, trough plasma concentrations of clozapine and norclozapine were also significantly associated with once-daily dosing regimen.

CONCLUSION

The study results support once-daily dosing of clozapine as a viable option to selected patients in clinical practice, as no association of severe symptoms or side effects were associated with once-daily dosing regimen. More studies are needed to examine the relationship between clinical outcomes and clozapine dosing regimen.

Hippocampal Network Dysfunction in Early Psychosis: A 2-Year Longitudinal Study

Background

Hippocampal abnormalities are among the most consistent findings in schizophrenia. Numerous studies have reported deficits in hippocampal volume, function, and connectivity in the chronic stage of illness. While hippocampal volume and function deficits are also present in the early stage of illness, there is mixed evidence of both higher and lower functional connectivity. Here, we use graph theory to test the hypothesis that hippocampal network connectivity is broadly lowered in early psychosis and progressively worsens over 2 years.

Methods

We examined longitudinal resting-state functional connectivity in 140 participants (68 individuals in the early stage of psychosis, 72 demographically similar healthy control individuals). We used an anatomically driven approach to quantify hippocampal network connectivity at 2 levels: 1) a core hippocampal-medial temporal lobe cortex (MTLC) network; and 2) an extended hippocampal-cortical network. Group and time effects were tested in a linear mixed effects model.

Results

Early psychosis patients showed elevated functional connectivity in the core hippocampal-MTLC network, but contrary to our hypothesis, did not show alterations within the broader hippocampal-cortical network. Hippocampal-MTLC network hyperconnectivity normalized longitudinally and predicted improvement in positive symptoms but was not associated with increasing illness duration.

Conclusions

These results show abnormally elevated functional connectivity in a core hippocampal-MTLC network in early psychosis, suggesting that selectively increased hippocampal signaling within a localized cortical circuit may be a marker of the early stage of psychosis. Hippocampal-MTLC hyperconnectivity could have prognostic and therapeutic implications.

Body mass index, waist circumference, insulin, and leptin plasma levels differentiate between clozapine-responsive and clozapine-resistant schizophrenia

BACKGROUND

Between 25% and 50% of patients suffering from treatment-resistant schizophrenia fail to achieve a clinical response with clozapine. The rapid identification and treatment of this subgroup of patients represents a challenge for healthcare practice.

AIMS

To evaluate the relationship between metabolic alterations and the clinical response to clozapine.

METHODS

A multicenter, observational, case-control study was performed. Patients diagnosed with schizophrenia treated with clozapine were eligible (minimum dose 400 mg/d for at least 8 weeks and/or clozapine plasma levels ⩾ 350 µg/mL). According to the Positive and Negative Syndrome Scale (PANSS) total score, patients were classified as clozapine-responsive (CR) (<80 points) or clozapine non-responsive (CNR) (⩾80 points). Groups were compared based on demographic and treatment-related characteristics, together with body mass index (BMI), waist circumference, insulin, leptin, and C-reactive protein plasma levels. Plasma levels of clozapine and its main metabolite, nor-clozapine, were measured in all the participants. In addition, the potential relationship between PANSS scores and leptin or insulin plasma levels was assessed.

RESULTS

A total of 46 patients were included: 25 CR and 21 CNR. BMI and waist circumference, fasting insulin and leptin plasma levels were lower in the CNR group, while C-reactive protein was not different. Moreover, significant negative correlations were observed between PANSS positive and general psychopathology subscores, on one hand, and insulin and leptin plasma levels, on the other hand, as well as between PANSS negative subscores and leptin plasma levels.

CONCLUSIONS

Our results suggest that the lack of metabolic effect induced by clozapine is associated with the lack of clinical response.

The histamine system and cognitive function: An in vivo H3 receptor PET imaging study in healthy volunteers and patients with schizophrenia

BACKGROUND

The histamine-3 receptor (H3R) is an auto- and heteroreceptor that inhibits the release of histamine and other neurotransmitters. Post-mortem evidence has found altered H3R expression in patients with psychotic disorders, which may underlie cognitive impairment associated with schizophrenia (CIAS).

AIMS

We used positron emission tomography (PET) imaging to compare brain uptake of an H3R selective tracer between patients with schizophrenia and matched controls (healthy individuals). Regions of interest included the dorsolateral prefrontal cortex (DLPFC) and striatum. We explored correlations between tracer uptake and symptoms, including cognitive domains.

METHODS

A total of 12 patients and 12 matched controls were recruited to the study and were assessed with psychiatric and cognitive rating scales. They received a PET scan using the H3R-specific radioligand [11C]MK-8278 to determine H3R availability.

RESULTS

There was no statistically significant difference in tracer uptake between patients and controls in the DLPFC (t19 = 0.79, p = 0.44) or striatum (t21 = 1.18, p = 0.25). An exploratory analysis found evidence for lower volume of distribution in the left cuneus (pFWE-corrected = 0.01). DLPFC tracer uptake was strongly correlated with cognition in controls (trail making test (TMT) A: r = 0.77, p = 0.006; TMT B: rho = 0.74, p = 0.01), but not in patients (TMT A: r = -0.18, p = 0.62; TMT B: rho = -0.06, p = 0.81).

CONCLUSIONS

These findings indicate H3R in the DLPFC might play a role in executive function and this is disrupted in schizophrenia in the absence of major alterations in H3R availability as assessed using a selective radiotracer for H3R. This provides further evidence for the role of H3R in CIAS.

A scoping review of literature on clozapine from former USSR states published in Russian language

OBJECTIVE

Access to literature on clozapine in Russian language remains strikingly limited. We aimed to identify and translate clinical evidence on clozapine-based treatment outcomes.

METHODS

We performed a systematic review in PubMed, Embase and scientific indexes from former USSR states searching for articles published in Russian from the database inception till January 2023 and summarized the data in a scoping review (PROSPERO Reg. Number CRD42023386737).

RESULTS

A total of 60 papers were included comprising eight main topic categories: 1) clozapine-related intoxications (n = 20), 2) effectiveness/efficacy and safety of clozapine treatment (n = 14), 3) adverse drug-induced reactions (ADRs) related to clozapine treatment (n = 9), 4) therapeutic drug monitoring for clozapine (n = 5), 5) combination of clozapine and non-pharmacological treatments (n = 4), 6) pharmacoepidemiology of clozapine (n = 3), 7) effects of clozapine on the brain electrical activity (n = 3), and 8) novel clozapine formulations (n = 2). Among clozapine-related intoxications there were reports of criminal poisoning, which was associated with low lethality. Worse outcomes were accompanied by systemic reactions to intoxications. Clinical benefits of hemoadsorption were reported in the management of clozapine-related intoxications. Only half of studies reporting clozapine effectiveness used standardized scales to assess outcomes. Clozapine superiority in treatment-resistant schizophrenia (TRS) was replicated in one trial. No reports of clozapine-related agranulocytosis were identified. Clozapine ranked among most prescribed antipsychotics for TRS and non-TRS.

CONCLUSIONS

As clinical research in former USSR states is advancing to adopt western clinical research standards, comparability and extrapolation of findings is expected to increase, with transfer of older findings to clinical practice being particularly challenging.

Correlates of severity in a clinical staging model of schizophrenia: a cross-sectional study among 158 subjects

BACKGROUND

Clinical staging has been widely used to predict and optimize the treatment of medical disorders. Different models have been proposed to map the development, progression, and extension of psychiatric disorders over time, mainly for schizophrenia. The primary objective of this study was to classify patients with psychosis according to the McGorry staging model and compare factors between the different stages.

METHODS

This was a cross-sectional study, collecting data from 158 patients hospitalized for schizophrenia/psychosis. The survey included the Mini International Neuropsychiatric Interview (MINI), Positive and Negative Symptom Scale (PANSS), Montgomery-Asberg Depression Rating Scale (MADRS), Yong Mania Rating Scale (YMRS), Clinical Global Impression (CGI) scale, and the McGorry staging model.

RESULTS

Patients have been classified into three clinical stages: relapse of psychotic disorder (43%), multiple relapses (47.5%), and persistent and severe illness (9.5%). A higher mean duration of hospitalization, psychotic symptoms (PANSS total scale and subscales), chlorpromazine equivalent dose, and number of antipsychotic treatments were found among participants in Stage 4 as compared to the other groups. However, a significantly higher mean GAF scale was found among participants in stage 3b as compared to the other groups.

CONCLUSION

Each stage in the McGorry staging model of schizophrenia is associated with well-defined clinical presentations, which help decide the appropriate treatment. Using such models in psychiatry can improve the diagnostic process and potential therapeutic interventions for patients suffering from mental disorders.

Discontinuation of antipsychotics in individuals with first-episode schizophrenia and its association to functional outcomes, hospitalization and death: a register-based nationwide follow-up study

BACKGROUND

Discontinuation of antipsychotic medication may be linked to high risk of relapse, hospitalization and mortality. This study investigated the use and discontinuation of antipsychotics in individuals with first-episode schizophrenia in relation to cohabitation, living with children, employment, hospital admission and death.

METHODS

Danish registers were used to establish a nationwide cohort of individuals ⩾18 years with schizophrenia included at the time of diagnosis in1995-2013. Exposure was antipsychotic medication calculated using defined daily dose and redeemed prescriptions year 2-5. Outcomes year 5-6 were analysed using binary logistic, negative binomial and Cox proportional hazard regression.

RESULTS

Among 21 351, 9.3% took antipsychotics continuously year 2-5, 38.6% took no antipsychotics, 3.4% sustained discontinuation and 48.7% discontinued and resumed treatment. At follow-up year 6, living with children or employment was significantly higher in individuals with sustained discontinuation (OR 1.98, 95% CI 1.53-2.56 and OR 2.60, 95% CI 1.91-3.54), non-sustained discontinuation (OR 1.25, 95% CI 1.05-1.48 and 2.04, 95% CI 1.64-2.53) and no antipsychotics (OR 2.00, 95% CI 1.69-2.38 and 5.64, 95% CI 4.56-6.97) compared to continuous users. Individuals with non-sustained discontinuation had more psychiatric hospital admissions (IRR 1.27, 95% CI 1.10-1.47) and longer admissions (IRR 1.68, 95% CI 1.30-2.16) year 5-6 compared to continuous users. Mortality during year 5-6 did not differ between groups.

CONCLUSION

Most individuals with first-episode schizophrenia discontinued or took no antipsychotics the first years after diagnosis and had better functional outcomes. Non-sustained discontinuers had more, and longer admissions compared to continuous users. However, associations found could be either cause or effect.

Impact of cognitive performance and negative symptoms on psychosocial functioning in Czech schizophrenia patients

Schizophrenia has a profound influence on the real-life functioning of patients. There are several factors inherent to the disease course affecting the level of psychosocial functioning. Our study focused on the impact of cognitive deficit and severity of negative symptoms (i.e., the experiential domain (avolition, asociality, and anhedonia) and the expressive domain (blunted affect and alogia)) to explore psychosocial functioning in schizophrenia. Schizophrenia patients (n = 211) were tested for the presence of cognitive impairment using the NIMH-MATRICS: Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Cattery (MCCB; MATRICS Consensus Cognitive Battery) and the extent of negative symptoms using the PANSS (PANSS; Positive and Negative Syndrome Scale-selected items). The level of psychosocial functioning was measured with the Personal and Social Performance Scale (PSP). The path analysis using three regression models was used to analyse variables influencing psychosocial functioning (PSP). One of these models analyzed influence of cognitive functioning (MCCB) and negative schizophrenia symptoms (PANSS selected items reflecting expressive and experiential deficits) as predictors and NART/CRT and disease length as confounders. R² was 0.54. The direct effect of the MCCB (β = 0.09) on the PSP was suppressed by the strong effect of the negative symptoms (β = -0.64). The presence of cognitive deficits and negative symptoms in our sample of schizophrenia patients significantly influences the level of their psychosocial functioning, a key factor in remission and recovery.

Short-term Clinical Outcome of Previously Untreated and Treated Schizophrenia and Impact of Duration of Untreated Psychosis

Background

Duration of untreated psychosis (DUP) is an important modifiable factor affecting schizophrenia outcomes. A dearth of research in India on untreated versus treated schizophrenia warrants further research.

Methods

This was a longitudinal study in a tertiary hospital over 2 years. Inpatients diagnosed with schizophrenia (N = 116), aged 18-45, were divided into untreated and treated groups. Diagnostic confirmation, severity assessment, and clinical outcome were done using ICD-10 criteria, Positive and Negative Syndrome Scale (PANSS), and Clinical Global Impression (CGI) scale. Follow-up was done at 12 and 24 weeks. DUP was measured, and its association with the outcome was assessed.

Results

Final analysis included 100 patients, 50 each of previously untreated and treated. Untreated patients had lower age and duration of illness (DOI), but higher DUP (p < .001). Treated patients showed much improvement on CGI-I at 12 weeks (p = .029), with no difference at 24 weeks. PANSS severity comparison showed no difference, and both groups followed a declining trend. In untreated patients, age of onset (AoO) was negatively correlated with severity (except general symptoms at baseline) at all follow-ups ('r' range = -0.32 to -0.49, p < .05), while DOI showed a positive correlation with negative and general symptoms at 12 weeks (r ~ 0.3, p < .05). Treated patients showed inconsistent and lower negative correlation between AoO and PANSS, with no correlation between severity and DOI. The mean sample DUP was 17.9 ± 31.6 weeks; it negatively correlated with education (r = -0.25, p = .01) and positively with PANSS severity ('r' range = 0.22 to 0.30, p < .05) at all follow-ups, especially negative symptoms. Patients with no or minimal improvement on CGI at 24 weeks had higher DUP (Quade's ANOVA F[1,98] = 6.24, p = .014).

Conclusion

Illness variables in untreated schizophrenia affect severity, which has delayed improvement than treated schizophrenia. Higher DUP is associated with negative symptoms of schizophrenia.

Short-term antipsychotic treatment response in early-onset, typical-onset, and late-onset first episode schizophrenia

In schizophrenia, the age at illness onset may reflect genetic loading and predict prognosis. We aimed to compare the pre-treatment symptom profiles and clinical symptom responses to antipsychotic treatment of individuals with late-onset schizophrenia (LOS; onset age: 40-59 years) with individuals with early-onset schizophrenia (EOS; onset age < 18 years) or typical-onset schizophrenia (TOS; onset age: 18-39 years). We conducted an 8-week cohort study in inpatient departments of five mental health hospitals in five cities in China. We included 106 individuals with LOS, 80 with EOS, and 214 with TOS. Their onset of schizophrenia was within three years and the disorders were minimally treated. The Positive and Negative Syndrome Scale (PANSS) was used to evaluate clinical symptoms at baseline and after 8 weeks of antipsychotic treatment. Mixed effect models were used to compare symptom improvement within eight weeks. Antipsychotic therapy reduced all PANSS factor scores in all three groups. LOS had significantly better improvement in PANSS positive factor scores than EOS at week 8 after adjusting for sex, duration of illness, dose equivalents of antipsychotics at baseline, sites as fixed effects, and individuals as random effects. LOS was associated with reduced positive factor scores at week 8 when receiving 1 mg olanzapine dose equivalent per 1 kg body weight compared with EOS or TOS. In conclusion, LOS had better early improvement of positive symptoms than EOS and TOS. Thus, personalized treatment for schizophrenia should consider the age of onset.

The relationship between striatal dopamine and anterior cingulate glutamate in first episode psychosis changes with antipsychotic treatment

The neuromodulator dopamine and excitatory neurotransmitter glutamate have both been implicated in the pathogenesis of psychosis, and dopamine antagonists remain the predominant treatment for psychotic disorders. To date no study has measured the effect of antipsychotics on both of these indices together, in the same population of people with psychosis. Striatal dopamine synthesis capacity (Kicer) and anterior cingulate glutamate were measured using 18F-DOPA positron emission tomography and proton magnetic resonance spectroscopy respectively, before and after at least 5 weeks' naturalistic antipsychotic treatment in people with first episode psychosis (n = 18) and matched healthy controls (n = 20). The relationship between both measures at baseline and follow-up, and the change in this relationship was analyzed using a mixed linear model. Neither anterior cingulate glutamate concentrations (p = 0.75) nor striatal Kicer (p = 0.79) showed significant change following antipsychotic treatment. The change in relationship between whole striatal Kicer and anterior cingulate glutamate, however, was statistically significant (p = 0.017). This was reflected in a significant difference in relationship between both measures for patients and controls at baseline (t = 2.1, p = 0.04), that was not present at follow-up (t = 0.06, p = 0.96). Although we did not find any effect of antipsychotic treatment on absolute measures of dopamine synthesis capacity and anterior cingulate glutamate, the relationship between anterior cingluate glutamate and striatal dopamine synthesis capacity did change, suggesting that antipsychotic treatment affects the relationship between glutamate and dopamine.

Self-stigma in schizophrenia: a systematic review and meta-analysis of 37 studies from 25 high- and low-to-middle income countries

In schizophrenia, it is currently thought that stigma experience is increased by psychotic and depressive symptomatology, exposure to stigma at the workplace, and that self-stigma levels vary across countries without knowing the factors explaining these variations. The aim of the present meta-analysis was to synthetize the data of observational studies comprehensively exploring multiple self-stigma dimensions and associated factors. A systematic literature search without language or time restrictions was conducted in Medline, Google Scholar, and Web of Science for studies, last 09/2021. Eligible studies that included ≥80% of patients diagnosed with schizophrenia-spectrum disorders and used a validated scale measuring self-stigma dimensions were meta-analysed using random-effects models, followed by subgroup and meta-regression analyses. Study registration: PROSPERO CRD42020185030. Overall, 37 studies (n = 7717) from 25 countries (5 continents) published between 2007 and 2020 were included, with 20 studies conducted in high-income countries. These studies used two scales with total scores ranging 1-4. The mean estimate of perceived stigma was 2.76 [95% confidence interval (CI) = 2.60-2.94], experienced stigma 2.29 [95% CI = 2.18, 2.41], alienation 2.40 [95% CI = 2.29, 2.52], stereotype endorsement 2.14 [95% CI = 2.03, 2.27], social withdrawal 2.28 [95% CI = 2.17, 2.39] and stigma resistance 2.53 [95% CI = 2.43, 2.63]). Self-stigma levels did not reduce over time. Living outside urban areas, low-income, singleness, unemployment, high antipsychotic dose and low functioning were associated with different stigma dimensions. Some stigma dimensions were lower in studies carried out in Europe compared to other regions. Most studies published since 2007 report that self-stigma is a particular concern for a specific subgroup of patients. This subgroup is characterized by unemployment, high antipsychotic dose and low functioning. We identified important other missing factors that should be explored to improve the effectiveness of public policies and personalized interventions to reduce self-stigma. Importantly, classical illness severity indices (psychotic severity, age at illness onset, illness duration) and sociodemographic variables (age, sex and education) were not associated with self-stigma, moderating previous findings.

Voice Patterns as Markers of Schizophrenia: Building a Cumulative Generalizable Approach Via a Cross-Linguistic and Meta-analysis Based Investigation

BACKGROUND AND HYPOTHESIS

Voice atypicalities are potential markers of clinical features of schizophrenia (eg, negative symptoms). A recent meta-analysis identified an acoustic profile associated with schizophrenia (reduced pitch variability and increased pauses), but also highlighted shortcomings in the field: small sample sizes, little attention to the heterogeneity of the disorder, and to generalizing findings to diverse samples and languages.

STUDY DESIGN

We provide a critical cumulative approach to vocal atypicalities in schizophrenia, where we conceptually and statistically build on previous studies. We aim at identifying a cross-linguistically reliable acoustic profile of schizophrenia and assessing sources of heterogeneity (symptomatology, pharmacotherapy, clinical and social characteristics). We relied on previous meta-analysis to build and analyze a large cross-linguistic dataset of audio recordings of 231 patients with schizophrenia and 238 matched controls (>4000 recordings in Danish, German, Mandarin and Japanese). We used multilevel Bayesian modeling, contrasting meta-analytically informed and skeptical inferences.

STUDY RESULTS

We found only a minimal generalizable acoustic profile of schizophrenia (reduced pitch variability), while duration atypicalities replicated only in some languages. We identified reliable associations between acoustic profile and individual differences in clinical ratings of negative symptoms, medication, age and gender. However, these associations vary across languages.

CONCLUSIONS

The findings indicate that a strong cross-linguistically reliable acoustic profile of schizophrenia is unlikely. Rather, if we are to devise effective clinical applications able to target different ranges of patients, we need first to establish larger and more diverse cross-linguistic datasets, focus on individual differences, and build self-critical cumulative approaches.

Semantic and Acoustic Markers in Schizophrenia-Spectrum Disorders: A Combinatory Machine Learning Approach

BACKGROUND AND HYPOTHESIS

Speech is a promising marker to aid diagnosis of schizophrenia-spectrum disorders, as it reflects symptoms like thought disorder and negative symptoms. Previous approaches made use of different domains of speech for diagnostic classification, including features like coherence (semantic) and form (acoustic). However, an examination of the added value of each domain when combined is lacking as of yet. Here, we investigate the acoustic and semantic domains separately and combined.

STUDY DESIGN

Using semi-structured interviews, speech of 94 subjects with schizophrenia-spectrum disorders (SSD) and 73 healthy controls (HC) was recorded. Acoustic features were extracted using a standardized feature-set, and transcribed interviews were used to calculate semantic word similarity using word2vec. Random forest classifiers were trained for each domain. A third classifier was used to combine features from both domains; 10-fold cross-validation was used for each model.

RESULTS

The acoustic random forest classifier achieved 81% accuracy classifying SSD and HC, while the semantic domain classifier reached an accuracy of 80%. Joining features from the two domains, the combined classifier reached 85% accuracy, significantly improving on separate domain classifiers. For the combined classifier, top features were fragmented speech from the acoustic domain and variance of similarity from the semantic domain.

CONCLUSIONS

Both semantic and acoustic analyses of speech achieved ~80% accuracy in classifying SSD from HC. We replicate earlier findings per domain, additionally showing that combining these features significantly improves classification performance. Feature importance and accuracy in combined classification indicate that the domains measure different, complementing aspects of speech.

Smartwatch digital phenotypes predict positive and negative symptom variation in a longitudinal monitoring study of patients with psychotic disorders

Introduction

Monitoring biometric data using smartwatches (digital phenotypes) provides a novel approach for quantifying behavior in patients with psychiatric disorders. We tested whether such digital phenotypes predict changes in psychopathology of patients with psychotic disorders.

Methods

We continuously monitored digital phenotypes from 35 patients (20 with schizophrenia and 15 with bipolar spectrum disorders) using a commercial smartwatch for a period of up to 14 months. These included 5-min measures of total motor activity from an accelerometer (TMA), average Heart Rate (HRA) and heart rate variability (HRV) from a plethysmography-based sensor, walking activity (WA) measured as number of total steps per day and sleep/wake ratio (SWR). A self-reporting questionnaire (IPAQ) assessed weekly physical activity. After pooling phenotype data, their monthly mean and variance was correlated within each patient with psychopathology scores (PANSS) assessed monthly.

Results

Our results indicate that increased HRA during wakefulness and sleep correlated with increases in positive psychopathology. Besides, decreased HRV and increase in its monthly variance correlated with increases in negative psychopathology. Self-reported physical activity did not correlate with changes in psychopathology. These effects were independent from demographic and clinical variables as well as changes in antipsychotic medication dose.

Discussion

Our findings suggest that distinct digital phenotypes derived passively from a smartwatch can predict variations in positive and negative dimensions of psychopathology of patients with psychotic disorders, over time, providing ground evidence for their potential clinical use.

Acoustic speech markers for schizophrenia-spectrum disorders: a diagnostic and symptom-recognition tool

BACKGROUND

Clinicians routinely use impressions of speech as an element of mental status examination. In schizophrenia-spectrum disorders, descriptions of speech are used to assess the severity of psychotic symptoms. In the current study, we assessed the diagnostic value of acoustic speech parameters in schizophrenia-spectrum disorders, as well as its value in recognizing positive and negative symptoms.

METHODS

Speech was obtained from 142 patients with a schizophrenia-spectrum disorder and 142 matched controls during a semi-structured interview on neutral topics. Patients were categorized as having predominantly positive or negative symptoms using the Positive and Negative Syndrome Scale (PANSS). Acoustic parameters were extracted with OpenSMILE, employing the extended Geneva Acoustic Minimalistic Parameter Set, which includes standardized analyses of pitch (F0), speech quality and pauses. Speech parameters were fed into a random forest algorithm with leave-ten-out cross-validation to assess their value for a schizophrenia-spectrum diagnosis, and PANSS subtype recognition.

RESULTS

The machine-learning speech classifier attained an accuracy of 86.2% in classifying patients with a schizophrenia-spectrum disorder and controls on speech parameters alone. Patients with predominantly positive v. negative symptoms could be classified with an accuracy of 74.2%.

CONCLUSIONS

Our results show that automatically extracted speech parameters can be used to accurately classify patients with a schizophrenia-spectrum disorder and healthy controls, as well as differentiate between patients with predominantly positive v. negatives symptoms. Thus, the field of speech technology has provided a standardized, powerful tool that has high potential for clinical applications in diagnosis and differentiation, given its ease of comparison and replication across samples.

Accelerated cortical thinning precedes and predicts conversion to psychosis: The NAPLS3 longitudinal study of youth at clinical high-risk

Progressive grey matter loss has been demonstrated among clinical high-risk (CHR) individuals who convert to psychosis, but it is unknown whether these changes occur prior to psychosis onset. Identifying illness-related neurobiological mechanisms that occur prior to conversion is essential for targeted early intervention. Among participants in the third wave of the North American Prodrome Longitudinal Study (NAPLS3), this report investigated if steeper cortical thinning was observable prior to psychosis onset among CHR individuals who ultimately converted (CHR-C) and assessed the shortest possible time interval in which rates of cortical thinning differ between CHR-C, CHR non-converters (CHR-NC), and health controls (HC). 338 CHR-NC, 42 CHR-C, and 62 HC participants (age 19.3±4.2, 44.8% female, 52.5% racial/ethnic minority) completed up to 5 MRI scans across 8 months. Accelerated thinning among CHR-C compared to CHR-NC and HC was observed in multiple prefrontal, temporal, and parietal cortical regions. CHR-NC also exhibited accelerated cortical thinning compared to HC in several of these areas. Greater percent decrease in cortical thickness was observed among CHR-C compared to other groups across 2.9±1.8 months, on average, in several cortical areas. ROC analyses discriminating CHR-C from CHR-NC by percent thickness change in a left hemisphere region of interest, scanner, age, age2, and sex had an AUC of 0.74, with model predictive power driven primarily by percent thickness change. Findings indicate that accelerated cortical thinning precedes psychosis onset and differentiates CHR-C from CHR-NC and HC across short time intervals. Mechanisms underlying cortical thinning may provide novel treatment targets prior to psychosis onset.

Reductions in synaptic marker SV2A in early-course Schizophrenia

Excess synaptic pruning during neurodevelopment has emerged as one of the leading hypotheses on the causal mechanism for schizophrenia. It proposes that excess synaptic elimination occurs during development before the formal onset of illness. Accordingly, synaptic deficits may be observable at all stages of illnesses, including in the early phases. The availability of [¹¹C]UCB-J, the first-in-human in vivo synaptic marker, represents an opportunity for testing this hypothesis with a relatively high level of precision. The first two published [¹¹C]UCB-J schizophrenia studies have documented significant, widespread reductions in binding in chronic patients. The present study tested the hypothesis that reductions are present in early-course patients. 18 subjects completed [¹¹C]UCB-J PET scans, (nine with schizophrenia, average duration of illness of 3.36 years, and nine demographically-matched healthy individuals). We compared binding levels, quantified as non-displaceable specific binding (BP_ND), in a set of a priori-specified brain regions of interest (ROIs). Eight ROIs (left and right hippocampus, right superior temporal and Heschl's gyrus, left and right putamen, and right caudal and rostral middle frontal gyrus) showed large reductions meeting Bonferroni corrected significant levels, p < 0.0036. Exploratory, atlas-wide analyses confirmed widespread reductions in schizophrenia. We also observed significant positive correlations between binding levels and cognitive performance and a negative correlation with the severity of delusions. These results largely replicate findings from chronic patients, indicating that extensive [¹¹C]UCB-J binding deficits are reliable and reproducible. Moreover, these results add to the growing evidence that excess synaptic pruning is a major disease mechanism for schizophrenia.

History of suicide attempt associated with amygdala and hippocampus changes among individuals with schizophrenia

Abnormalities in subcortical brain structures may reflect higher suicide risk in mood disorders, but less is known about its associations for schizophrenia. This cross-sectional imaging study aimed to explore whether the history of suicide attempts was associated with subcortical changes among individuals with schizophrenia. We recruited 44 individuals with schizophrenia and a history of suicide attempts (SZ-SA) and 44 individuals with schizophrenia but without a history of suicide attempts (SZ-NSA) and 44 healthy controls. Linear regression showed that SZ-SA had smaller volumes of the hippocampus (Cohen's d = -0.72), the amygdala (Cohen's d = -0.69), and some nuclei of the amygdala (Cohen's d, -0.57 to -0.72) than SZ-NSA after adjusting for age, sex, illness phase, and intracranial volume. There was no difference in the volume of the subfields of the hippocampus. It suggests the history of suicide attempts is associated with subcortical volume alterations in schizophrenia.

Comparison of antipsychotic dose equivalents for acute bipolar mania and schizophrenia

QUESTION

Are antipsychotic dose equivalents between acute mania and schizophrenia the same?

STUDY SELECTION AND ANALYSIS

Six databases were systematically searched (from inception to 17 September 2022) to identify blinded randomised controlled trials (RCTs) that used a flexible-dose oral antipsychotic drug for patients with acute mania. The mean and SD of the effective dose and the pre-post changes in manic symptoms were extracted. A network meta-analysis (NMA) under a frequentist framework was performed to examine the comparative efficacy between the antipsychotics. A classic mean dose method (sample size weighted) was used to calculate each antipsychotic dose equivalent to 1 mg/day olanzapine for acute mania. The antipsychotic dose equivalents of acute mania were compared with published data for schizophrenia.

FINDINGS

We included 42 RCTs which enrolled 11 396 participants with acute mania. The NMA showed that risperidone was superior to olanzapine (reported standardised mean difference: -022, 95% CI -0.41 to -0.02), while brexpiprazole was inferior to olanzapine (standardised mean difference: 0.36, 95% CI 0.08 to 0.64). The dose equivalents to olanzapine (with SD) were 0.68 (0.23) for haloperidol, 0.32 (0.07) for risperidone, 0.60 (0.11) for paliperidone, 8.00 (1.41) for ziprasidone, 41.46 (5.98) for quetiapine, 1.65 (0.32) for aripiprazole, 1.23 (0.20) for asenapine, 0.53 (0.14) for cariprazine and 0.22 (0.03) for brexpiprazole. Compared with the olanzapine dose equivalents for schizophrenia, those of acute mania were higher for quetiapine (p<0.001, 28.5%) and aripiprazole (p<0.001, 17.0%), but lower for haloperidol (p<0.001, -8.1%) and risperidone (p<0.001, -15.8%).

CONCLUSIONS

Antipsychotic drugs have been considered first-line treatment for acute mania, warranting specific dose equivalence for scientific and clinical purposes.

Longitudinal Changes in Cortical Surface Area Associated With Transition to Psychosis in Adolescents at Clinical High Risk for the Disease

OBJECTIVE

Identifying biomarkers of transition to psychosis in individuals at clinical high risk for psychosis (CHR-P) is essential to understanding the mechanisms underlying the disease. Although cross-sectional abnormalities in cortical surface area (CSA) have been demonstrated in individuals at CHR-P who transition to psychosis (CHR-P-T) compared with those who do not (CHR-P-NT), how CSA longitudinally develops remains unclear, especially in younger individuals. We set out to compare CSA in adolescents at CHR-P and healthy controls (HC) over 2 points in time.

METHOD

A longitudinal multicenter study was performed in adolescents at CHR-P in comparison to HC and according to transition to psychosis. Magnetic resonance imaging scans were acquired at baseline, at 18-month follow-up, or at the time of transition. Images were pre-processed and hemisphere and regional CSA were computed using FreeSurfer. Between-group analyses were performed with linear mixed-effects models.

RESULTS

A total of 313 scans (107 CHR-P and 102 HC) were included in the analysis. At 18 months, the rate of transition to psychosis in CHR-P was 23.4%. Adolescents at CHR-P-T presented greater age-related decrease in CSA in the left parietal and occipital lobes compared with HC, and in the bilateral parietal lobe and right frontal lobe relative to CHR-P-NT. These results were not influenced by antipsychotic treatment, cannabis use, or intelligence quotient (IQ).

CONCLUSION

Adolescents at CHR-P that developed a psychotic disorder presented different developmental trajectories of CSA relative to those who did not. A relatively greater decrease in CSA in the parietal and frontal lobes may index clinical transition to psychosis in adolescents at CHR-P.

3-year incidence and predictors of metabolic syndrome in schizophrenia in the national FACE-SZ cohort

AIMS

Metabolic Syndrome (MetS) is a major health epidemic of Western countries and patients with schizophrenia is a particularly vulnerable population due to lifestyle, mental illness and treatment factors. However, we lack prospective data to guide prevention. The aim of our study is then to determine MetS incidence and predictors in schizophrenia.

METHOD

Participants were recruited in 10 expert centers at a national level and followed-up for 3 years. MetS was defined according to the International Diabetes Federation criteria. Inverse probability weighting methods were used to correct for attrition bias.

RESULTS

Among the 512 participants followed-up for 3 years, 77.9% had at least one metabolic disturbance. 27.5% were identified with MetS at baseline and excluded from the analyses. Among the rest of participants (N = 371, mean aged 31.2 (SD = 9.1) years, with mean illness duration of 10.0 (SD = 7.6) years and 273 (73.6%) men), MetS incidence was 20.8% at 3 years and raised to 23.6% in tobacco smokers, 29.4% in participants receiving antidepressant prescription at baseline and 42.0% for those with 2 disturbed metabolic disturbances at baseline. Our multivariate analyses confirmed tobacco smoking and antidepressant consumption as independent predictors of MetS onset (adjusted odds ratios (aOR) = 3.82 [1.27-11.45], p = 0.016, and aOR = 3.50 [1.26-9.70], p = 0.0158). Antidepressant prescription predicted more specifically increased lipid disturbances and paroxetine was associated with the highest risk of MetS onset.

CONCLUSION

These results are an alarm call to prioritize MetS prevention and research in schizophrenia. We have listed interventions that should be actively promoted in clinical practice.

Sex Differences in Serum Prolactin Levels in Children and Adolescents on Antipsychotics: A Systematic Review and Meta-Analysis

BACKGROUND

Serum prolactin levels are influenced by sex, physical development and medications among other factors. Antipsychotics usually increase serum prolactin levels in both adults and younger patients, but no study has reviewed the potential association between sex and vulnerability for developing hyperprolactinemia among children and adolescents.

OBJECTIVE

Systematic review and meta-analysis of serum prolactin levels in children and adolescents on antipsychotic treatment for any psychiatric diagnosis to determine the effect of sex.

METHODS

A systematic search was performed in MEDLINE/PubMed/Web of Science and Cochrane databases for randomized controlled trials of antipsychotics in children and adolescents reporting serum prolactin levels by sex.

RESULTS

Of 1278 identified records, seven studies were included, comparing different single antipsychotics to placebo (risperidone N=4; lurasidone N=1; olanzapine N=1; queriapine N=1). Both male and female children and adolescents on antipsychotics presented a significant increase in prolactin levels relative to subjects receiving a placebo. (Male: 16.53 with 95% CI: 6.15-26.92; Female: 26.97 with 95% CI: 9.18-44.75). The four studies using risperidone had similar findings (Male: 26.49 with 95% CI: 17.55-35.43; Female: 37.72 with 95% CI: 9.41-66.03). In the direct comparison between sexes, females showed greater increases in prolactin, but the differences were not statistically significant.

CONCLUSION

Serum prolactin levels are increased in children and adolescents of both sexes on antipsychotics, with females showing a slightly greater increase than males. Further research is needed to clarify the influence of sex and pubertal status on prolactin levels in children and adolescents taking antipsychotics.

Anterior hippocampal dysfunction in early psychosis: a 2-year follow-up study

BACKGROUND

Cross-sectional studies indicate that hippocampal function is abnormal across stages of psychosis. Neural theories of psychosis pathophysiology suggest that dysfunction worsens with illness stage. Here, we test the hypothesis that hippocampal function is impaired in the early stage of psychosis and declines further over the next 2 years.

METHODS

We measured hippocampal function over 2 years using a scene processing task in 147 participants (76 individuals in the early stage of a non-affective psychotic disorder and 71 demographically similar healthy control individuals). Two-year follow-up was completed in 97 individuals (50 early psychosis, 47 healthy control). Voxelwise longitudinal analysis of activation in response to scenes was carried out within a hippocampal region of interest to test for group differences at baseline and a group by time interaction.

RESULTS

At baseline, we observed lower anterior hippocampal activation in the early psychosis group relative to the healthy control group. Contrary to our hypothesis, hippocampal activation remained consistent and did not show the predicted decline over 2 years in the early psychosis group. Healthy controls showed a modest reduction in hippocampal activation after 2 years.

CONCLUSIONS

The results of this study suggest that hippocampal dysfunction in early psychosis does not worsen over 2 years and highlight the need for longer-term longitudinal studies.

Excessive response to provocation rather than disinhibition mediates irritable behaviour in Huntington's disease

Background

Irritable and impulsive behaviour are common in Huntington's disease (HD: an autosomal dominant disorder causing degeneration in cortico-striatal networks). However, the cognitive mechanisms underlying these symptoms remain unclear, and previous research has not determined if common mechanisms underpin both symptoms. Here we used established and novel tasks to probe different aspects of irritable and impulsive behaviour to determine the neural mechanisms involved.

Methods

We recruited a cohort of 53 gene positive HD participants and 26 controls from non-affected family members and local volunteers. We used established questionnaire measures of irritability in HD (Snaith Irritability Scale, Problem Behaviours Assessment) and impulsivity [Urgency, Premeditation Perseverance, Sensation-seeking, Positive urgency scale (UPPSP), Barratt Impulsivity Scale], in addition to cognitive tasks of provocation, motor inhibition, delay discounting and decision making under uncertainty. We used generalised linear models to determine differences between cases and controls, and associations with irritability in the HD group.

Results

We found differences between cases and controls on the negative urgency subscale of the UPPSP, which was associated with irritability in HD. The frustrative non-reward provocation task also showed differences between cases and controls, in addition to predicting irritability in HD. The stop signal reaction time task showed case-control differences but was not associated with irritability in HD. None of the other measures showed group differences or predicted irritability in HD after correcting for confounding variables.

Discussion

Irritability in HD is mediated by excessive response to provocation, rather than a failure of motor inhibition.

Parkinson's Disease-Related Brain Metabolic Pattern Is Expressed in Schizophrenia Patients during Neuroleptic Drug-Induced Parkinsonism

Drug-induced parkinsonism (DIP) is a frequent parkinsonian syndrome that appears as a result of pharmacotherapy for the management of psychosis. It could substantially hamper treatment and therefore its diagnosis has a direct influence on treatment effectiveness. Although of such high importance, there is a lack of systematic research for developing neuroimaging-based criteria for DIP diagnostics for such patients. Therefore, the current study was aimed at applying a metabolic brain imaging approach using the 18F-FDG positron emission tomography and spatial covariance analysis to reveal possible candidates for DIP markers. As a result, we demonstrated, to our knowledge, the first attempt at the application of the Parkinson's Disease-Related Pattern (PDRP) as a metabolic signature of parkinsonism for the assessment of PDRP expression for schizophrenia patients with DIP. As a result, we observed significant differences in PDRP expression between the control group and the groups with PD and DIP patients. Similar differences in PDRP expression were also found when the non-DIP schizophrenia patients were compared with the PD group. Therefore, our findings made it possible to conclude that PDRP is a promising tool for the development of clinically relevant criteria for the estimation of the risk of developing DIP.

High Risk, High Dose?-Pharmacotherapeutic Prescription Patterns of Offender and Non-Offender Patients with Schizophrenia Spectrum Disorder

Compared to acute or community settings, forensic psychiatric settings, in general, have been reported to make greater use of antipsychotic polypharmacy and/or high dose pharmacotherapy, including overdosing. However, there is a scarcity of research specifically on offender patients with schizophrenia spectrum disorders (SSD), although they make up a large proportion of forensic psychiatric patients. Our study, therefore, aimed at evaluating prescription patterns in offender patients compared to non-offender patients with SSD. After initial statistical analysis with null-hypothesis significance testing, we evaluated the interplay of the significant variables and ranked them in accordance with their predictive power through application of supervised machine learning algorithms. While offender patients received higher doses of antipsychotics, non-offender patients were more likely to receive polypharmacologic treatment as well as additional antidepressants and benzodiazepines. To the authors' knowledge, this is the first study to evaluate a homogenous group of offender patients with SSD in comparison to non-offender controls regarding patterns of antipsychotic and other psychopharmacologic prescription patterns.

First-episode psychotic disorders in the wake of the COVID-19 pandemic: a descriptive review of casereports

OBJECTIVE

Since the onset of COVID-19 pandemic, many case reports and case series dealt with new-onset psychotic disorders in patients either infected with SARS-CoV-2 or thematically linked to the pandemic, but without an infection. Our aim was to provide a comprehensive collection of these reports to illustrate the nature of these psychoses.

METHODS

We conducted a literature search in MEDLINE, Embase, PsycINFO, using search terms regarding first-episode psychotic disorders in the context of corona.

RESULTS

96 case reports or case series covering 146 patients (62 without and 84 with SARS-CoV-2 infection) were found. Compared to patients without infection, patients with infection showed significantly more often visual hallucinations (28.6% vs 8.1%), confusion (36.9% vs 11.3%), an acute onset of illness (88.5% vs 59.6%) and less often depression (13.1% vs 35.5%) and a delusional content related to the pandemic (29.5% vs 78.3%). Both groups had an equally favourable outcome with a duration of psychosis ≤2 weeks in half and full remission in two-thirds of patients. In patients with infection, signs of inflammation were reported in 78.3% and increased CRP in 58.6%. While reports on patients with infection are continuously published, no report about patients without infection was found after July 2020.

CONCLUSION

Cases without infection were considered reactive and originated all from the first wave of the corona pandemic. In cases with infection, inflammation was considered as the main pathogenetic factor but was not found in all patients. Diagnosis was impeded by the overlap of psychosis with delirium.

Efficacy and safety of nitrous oxide for patients with treatment-resistant depression, a randomized controlled trial

Nitrous oxide (N₂O), an N-methyl-D-aspartate glutamate receptor antagonist, has demonstrated a rapid-onset antidepressant effect for treatment-resistant depression (TRD) preliminarily in the United States. This study aimed to test the efficacy and safety of N₂O for TRD patients in China. In this double-blinded, placebo-controlled trial, 44 patients with TRD were randomized to receive a one-hour inhalation of a mixture of either 50% N₂O/50% oxygen (N₂O group) or 50% air/50% oxygen (placebo group). The primary outcome was the change on the 17-item Hamilton Depression Rating Scale (HDRS-17) over a course of two weeks. Using modified intention-to-treat analysis, the between group difference was found in the HDRS-17 score at two hours and 24 h after inhalation treatment, while no significant difference was found in week one and week two. Patients receiving N₂O reported a significantly higher number of adverse events. All the adverse events lasted for no more than 24 h. No serious adverse events were reported. A single inhalation of 50% N₂O effectively alleviates depression in patients with TRD in China. The efficacy lasts for no more than one week. N₂O is safe for patients with TRD.

Subtyping negative symptoms in first-episode psychosis: Contrasting persistent negative symptoms with a data-driven approach

Persistent negative symptoms (PNS) are linked to poor functional outcomes and may be primary or caused by secondary factors. Although several studies have examined PNS in first-episode psychosis (FEP), a comparison with a data-driven approach is lacking. Here, we compared clinically defined PNS subgroups with class trajectories identified through latent growth modeling (LGM). Patients admitted to an early intervention service (N = 392) were classified as PNS (n = 105), secondary PNS (sPNS; n = 74), or non-PNS (n = 213) based on longitudinal data collected six to twelve months after admission. LGM was used to stratify patients based on similar negative symptom course over the same time period. Using multiple linear regression, we assessed the utility of both approaches in predicting Social and Occupational Functioning Assessment Scale (SOFAS) scores at two-year follow-up. Three negative symptom trajectories were identified: low and remitting (LR; n = 158), moderate and improving (MI; n = 163) and delayed partial response (DR; n = 71). Most non-PNS patients followed the LR trajectory, while patients with PNS or sPNS were generally divided between MI and DR. Both PNS classification and trajectory membership were significant predictors of two-year functional outcomes; the DR and MI trajectories predicted greater increases in SOFAS scores (DR: b = -19.14; MI: b = -11.54) than either sPNS (b = -9.19) or PNS (b = -6.46). These findings demonstrate that combining PNS and symptom-based stratification can predict functional outcomes more accurately than either taxonomy alone. Such a combined approach could yield significant advances in developing more targeted interventions for patients at risk for poor functional outcomes.

Recommendations of the Schizophrenia Expert Center network for adequate physical activity in real-world schizophrenia (FACE-SZ)

The World Health Organization (WHO) recommends adults complete 150-300 min per week of moderate physical activity or 75-150 min of vigorous physical activity or an equivalent combination of both, to optimize health. To explore the factors associated with adequate MVPA in stabilized outpatients with schizophrenia. 425 stabilized outpatients were recruited in the national FACE-SZ cohort between 2015 and 2018 were evaluated with the International Physical Activity Questionnaire and a 1-day long standardized battery. We explored in multivariate analyses the clinical and pharmacological factors associated with MVPA (model 1) and the biological factors and patient-reported outcomes (model 2). Overall, only 86 (20.2%) of the 425 participants achieved the recommended MVPA threshold. In model 1, the adequate MVPA group was associated with younger age, mood stabilizers prescription and adherence to treatment, independent of sex, positive and depressive symptoms, first-generation antipsychotics prescription, anxiolytic medication, and akathisia. In model 2, adequate MVPA was associated with better glycemic and lipidic profile and better physical and psychological well-being, self-esteem, sentimental life, and resilience independently of age, sex, and current psychotic severity. The expert centers recommend the importance of promoting promote effective MVPA programs for stabilized patients with schizophrenia. Interventions studies suggest that MVPA may be a useful strategy to maximize physical and psychological well-being and self-esteem and potentially to prevent or manage metabolic disturbances.

The relation between second-generation antipsychotics and laxative use in elderly patients with schizophrenia

BACKGROUND

We aimed to investigate factors associated with concomitant laxative use among elderly patients with schizophrenia, discharged on second-generation antipsychotics (SGAs), from two large public psychiatric hospitals in Taiwan.

METHODS

Elderly patients with schizophrenia who were discharged between 2006 and 2019 and received SGA monotherapy at discharge were included in the analysis. Multivariate logistic regression was used to identify factors associated with regular laxative use at discharge. The Cochrane-Armitage trend test was used to evaluate whether significant time trends existed for rates of laxative use at discharge.

RESULTS

A total of 2591 elderly patients with schizophrenia were discharged during the study period, and 1727 of 2591 patients who met the inclusion criteria were included for analysis. Of these 1727 patients, 732 (42.4%) also received concomitant laxatives. Female gender, mood stabiliser use and concomitant diabetes mellitus were found to be associated with increased laxative use. Among SGAs, clozapine was associated with the highest rate of laxative use, followed by zotepine, quetiapine, olanzapine and risperidone. Additionally, risperidone, amisulpride, aripiprazole, paliperidone and sulpiride were associated with comparable rates of laxative use. Laxative use rates grew over time from 30.8% in 2006 to 46.6% in 2019 (z = 4.83, P < 0.001).

CONCLUSIONS

Laxative use is common in elderly schizophrenia patients treated with SGAs. In cases of clinically significant constipation, switching to an SGA with a lower risk for constipation, or discontinuing the use of mood stabilisers should be considered, if clinically feasible.

The association between N-methyl-d-aspartate receptor availability and glutamate levels: A multi-modal PET-MR brain imaging study in first-episode psychosis and healthy controls

BACKGROUND

Evidence from post-mortem studies and in vivo imaging studies suggests there may be reduced N-methyl-d-aspartate receptor (NMDAR) levels in the hippocampus in patients with schizophrenia. Other studies have reported increased glutamate in striatum in schizophrenia patients. It has been hypothesised that NMDAR hypofunction leads to the disinhibition of glutamatergic signalling; however, this has not been tested in vivo.

METHODS

In this study, we investigated the relationship between hippocampal NMDAR and striatal glutamate using simultaneous positron emission tomography-magnetic resonance (PET-MR) imaging. We recruited 40 volunteers to this cross-sectional study; 21 patients with schizophrenia, all in their first episode of illness, and 19 healthy controls. We measured hippocampal NMDAR availability using the PET ligand [18F]GE179. This was indexed relative to whole brain as the distribution volume ratio (DVR). Striatal glutamatergic indices (glutamate and Glx) were acquired simultaneously, using combined PET-MR proton magnetic resonance spectroscopy (1H-MRS).

RESULTS

A total of 33 individuals (15 healthy controls, 18 patients) were included in the analyses (mean (SD) age of controls, 27.31 (4.68) years; mean (SD) age of patients, 24.75 (4.33), 27 male and 6 female). We found an inverse relationship between hippocampal DVR and striatal glutamate levels in people with first-episode psychosis (rho = -0.74, p < 0.001) but not in healthy controls (rho = -0.22, p = 0.44).

CONCLUSION

This study show that lower relative NMDAR availability in the hippocampus may drive increased striatal glutamate levels in patients with schizophrenia. Further work is required to determine whether these findings may yield new targets for drug development in schizophrenia.

The effect of antipsychotics on glutamate levels in the anterior cingulate cortex and clinical response: A 1H-MRS study in first-episode psychosis patients

Introduction

Glutamatergic dysfunction is implicated in the pathophysiology of schizophrenia. It is unclear whether glutamatergic dysfunction predicts response to treatment or if antipsychotic treatment influences glutamate levels. We investigated the effect of antipsychotic treatment on glutamatergic levels in the anterior cingulate cortex (ACC), and whether there is a relationship between baseline glutamatergic levels and clinical response after antipsychotic treatment in people with first episode psychosis (FEP).

Materials and methods

The sample comprised 25 FEP patients; 22 completed magnetic resonance spectroscopy scans at both timepoints. Symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS).

Results

There was no significant change in glutamate [baseline 13.23 ± 2.33; follow-up 13.89 ± 1.74; t(21) = -1.158, p = 0.260], or Glx levels [baseline 19.64 ± 3.26; follow-up 19.66 ± 2.65; t(21) = -0.034, p = 0.973]. There was no significant association between glutamate or Glx levels at baseline and the change in PANSS positive (Glu r = 0.061, p = 0.777, Glx r = -0.152, p = 0.477), negative (Glu r = 0.144, p = 0.502, Glx r = 0.052, p = 0.811), general (Glu r = 0.110, p = 0.607, Glx r = -0.212, p = 0.320), or total scores (Glu r = 0.078, p = 0.719 Glx r = -0.155, p = 0.470).

Conclusion

These findings indicate that treatment response is unlikely to be associated with baseline glutamatergic metabolites prior to antipsychotic treatment, and there is no major effect of antipsychotic treatment on glutamatergic metabolites in the ACC.