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.

Impact of Cognitive Impairments on Health-Related Quality of Life in Schizophrenia.

The impact of cognitive impairments on the health-related quality of life (HRQoL) in individuals with schizophrenia is unclear. The aim of this study was to examine the association between cognitive impairments and HRQoL in individuals with schizophrenia. A total of 609 individuals with schizophrenia were assessed on the Positive and Negative Syndrome Scale (PANSS) and a neurocognitive battery which comprised of the Wechsler Abbreviated Scale of Intelligence matrix reasoning, the Benton Judgment of Line Orientation Test, Continuous Performance Tests-Identical Pairs, and the Brief Assessment of Cognition in Schizophrenia.

Social skills, negative symptoms and real-world functioning in individuals at ultra-high risk of psychosis.

Background: Impairment in real-world social functioning is observed in individuals at Ultra-High Risk (UHR) of psychosis. Both social skills and negative symptoms appear to influence real-world functioning. This study aims to examine the psychometric properties of a social skills measure, the High-Risk Social Challenge task (HiSoC), and evaluate the relationship between social skills, negative symptoms, and real-world functioning in UHR individuals.

Comparative study of emotion recognition and theory of mind between major depressive disorder and schizophrenia.

Background: Social cognition as a transdiagnostic construct between major depressive disorder (MDD) and schizophrenia (SCZ) is not well understood. This may be attributed to the variability of social cognitive measures indexing the same construct. This study aims to compare emotion recognition and theory of mind domains, known to be impaired in SCZ, between MDD and SCZ.

Large-scale evaluation of the Positive and Negative Syndrome Scale (PANSS) symptom architecture in schizophrenia.

Although the Positive and Negative Syndrome Scale (PANSS) is widely utilized in schizophrenia research, variability in specific item loading exist, hindering reproducibility and generalizability of findings across schizophrenia samples. We aim to establish a common PANSS factor structure from a large multi-ethnic sample and validate it against a meta-analysis of existing PANSS models. Schizophrenia participants (N = 3511) included in the current study were part of the Singapore Translational and Clinical Research Program (STCRP) and the Clinical Antipsychotic Trials for Intervention Effectiveness (CATIE).

Genome wide study of tardive dyskinesia in schizophrenia.

Tardive dyskinesia (TD) is a severe condition characterized by repetitive involuntary movement of orofacial regions and extremities. Patients treated with antipsychotics typically present with TD symptomatology. Here, we conducted the largest GWAS of TD to date, by meta-analyzing samples of East-Asian, European, and African American ancestry, followed by analyses of biological pathways and polygenic risk with related phenotypes.

Genetic liability in individuals at ultra-high risk of psychosis: A comparison study of 9 psychiatric traits.

Individuals at ultra-high risk (UHR) of psychosis are characterised by the emergence of attenuated psychotic symptoms and deterioration in functioning. In view of the high non-psychotic comorbidity and low rates of transition to psychosis, the specificity of the UHR status has been called into question. This study aims to (i) investigate if the UHR construct is associated with the genetic liability of schizophrenia or other psychiatric conditions; (ii) examine the ability of polygenic risk scores (PRS) to discriminate healthy controls from UHR, remission and conversion status.

Cognitive Subtyping in Schizophrenia: A Latent Profile Analysis.

Cognitive dysfunction is a core feature of schizophrenia. The subtyping of cognitive performance in schizophrenia may aid the refinement of disease heterogeneity. The literature on cognitive subtyping in schizophrenia, however, is limited by variable methodologies and neuropsychological tasks, lack of validation, and paucity of studies examining longitudinal stability of profiles.

Evaluation of social cognitive measures in an Asian schizophrenia sample.

Background: Converging evidence has indicated that deficits in social cognition may manifest as poor functioning; therefore, social cognition has emerged as an important research area and treatment target. However, few studies have examined the psychometrics of multiple social cognition measures in an Asian population. This study aims to evaluate the psychometrics of measures indexing the four core social cognition domains.

Factor structure of the positive and negative syndrome scale (PANSS) in people at ultra high risk (UHR) for psychosis.

Introduction: The Positive and Negative Syndrome Scale (PANSS), a comprehensive psychopathology assessment scale used in the evaluation of psychopathology in schizophrenia, is also often used in the Ultra-High-Risk (UHR) population. This paper examined the dimensional structure of the PANSS in a UHR sample.

Methods: A total of 168 individuals assessed to be at UHR for psychosis on the Comprehensive Assessment of At-Risk Mental States (CAARMS) were evaluated on the PANSS, Calgary Depression Scale for Schizophrenia (CDSS), Beck Anxiety Inventory (BAI), Brief Assessment of Cognition in Schizophrenia (BACS), and Global Assessment of Functioning (GAF).

A Systematic Review of the Effectiveness of Medical Cannabis for Psychiatric, Movement and Neurodegenerative Disorders.

The discovery of endocannabinoid's role within the central nervous system and its potential therapeutic benefits have brought forth rising interest in the use of cannabis for medical purposes. The present review aimed to synthesize and evaluate the available evidences on the efficacy of cannabis and its derivatives for psychiatric, neurodegenerative and movement disorders. A systematic search of randomized controlled trials of cannabis and its derivatives were conducted via databases (PubMed, Embase and the Cochrane Central Register of Controlled Trials).