Associations between structural brain changes and blood neurofilament light chain protein in treatment-resistant schizophrenia.

Objective: Around 30% of people with schizophrenia are refractory to antipsychotic treatment (treatment-resistant schizophrenia). Abnormal structural neuroimaging findings, in particular volume and thickness reductions, are often described in schizophrenia. Novel biomarkers of active brain pathology such as neurofilament light chain protein are now expected to improve current understanding of psychiatric disorders, including schizophrenia.

Prevalence Estimates of Cytochrome P450 Phenoconversion in Youth Receiving Pharmacotherapy for Mental Health Conditions.

Pharmacogenetics-predicted drug metabolism may not match clinically observed metabolism due to a phenomenon known as phenoconversion. Phenoconversion can occur when an inhibitor or inducer of a drug-metabolizing enzyme is present. Although estimates of phenoconversion in adult populations are available, prevalence estimates in youth populations are limited.

Plasma neurofilament light outperforms glial fibrillary acidic protein in differentiating behavioural variant frontotemporal dementia from primary psychiatric disorders.

Objective: Timely, accurate distinction between behavioural variant frontotemporal dementia (bvFTD) and primary psychiatric disorders (PPD) is a clinical challenge. Blood biomarkers such as neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP) have shown promise. Prior work has shown NfL helps distinguish FTD from PPD.

The Pharmacogenomics Global Research Network Implementation Working Group: global collaboration to advance pharmacogenetic implementation.

Pharmacogenetics promises to optimize treatment-related outcomes by informing optimal drug selection and dosing based on an individual's genotype in conjunction with other important clinical factors. Despite significant evidence of genetic associations with drug response, pharmacogenetic testing has not been widely implemented into clinical practice. Among the barriers to broad implementation are limited guidance for how to successfully integrate testing into clinical workflows and limited data on outcomes with pharmacogenetic implementation in clinical practice.

DNA methylation and histone modifications associated with antipsychotic treatment: a systematic review.

Antipsychotic medications are essential when treating schizophrenia spectrum and other psychotic disorders, but the efficacy and tolerability of these medications vary from person to person. This interindividual variation is likely mediated, at least in part, by epigenomic processes that have yet to be fully elucidated. Herein, we systematically identified and evaluated 65 studies that examine the influence of antipsychotic drugs on epigenomic changes, including global methylation (9 studies), genome-wide methylation (22 studies), candidate gene methylation (16 studies), and histone modification (18 studies).

Plasma neurofilament light protein is differentially associated with age in individuals with treatment-resistant schizophrenia and bipolar affective disorder compared to controls.

Accelerated brain ageing has been observed in multiple psychiatric disorders. This study examined whether relationships between age and plasma neurofilament light (NfL) protein differed in individuals with psychiatric disorders (major depressive disorder (n = 42), bipolar affective disorder (n = 121), treatment-resistant schizophrenia (TRS, n = 82)) compared to two healthy control (HC) groups (n = 1,926 and n = 59). Compared to two independent HC samples, individuals with TRS demonstrated a stronger positive relationship between age and NfL levels.

Recommendations for pharmacogenetic testing in clinical practice guidelines in the US.

Purpose: Pharmacogenetic testing can identify patients who may benefit from personalized drug treatment. However, clinical uptake of pharmacogenetic testing has been limited. Clinical practice guidelines recommend biomarker tests that the guideline authors deem to have demonstrated clinical utility, meaning that testing improves treatment outcomes.

Associations between structural brain changes and blood neurofilament light chain protein in treatment-resistant schizophrenia.

Background And Hypothesis: Around 30% of people with schizophrenia are refractory to antipsychotic treatment (treatment-resistant schizophrenia; TRS). While abnormal structural neuroimaging findings, in particular volume and thickness reductions, are often observed in schizophrenia, it is anticipated that biomarkers of neuronal injury like neurofilament light chain protein (NfL) can improve our understanding of the pathological basis underlying schizophrenia. The current study aimed to determine whether people with TRS demonstrate different associations between plasma NfL levels and regional cortical thickness reductions compared with controls.

Impact of patient-specific factors on clozapine metabolism in individuals with treatment-resistant schizophrenia or schizoaffective disorder.

Background: There is high inter-individual variability in clozapine metabolism due to genetic and non-genetic differences. Patient-specific factors such as smoking, inflammation indicated by elevated C-reactive protein (CRP), and certain concurrent medications have a significant influence on clozapine metabolism.

Aim: To assess which patient-specific factors best explain variability in clozapine metabolism estimated by clozapine concentration to dose (C/D) ratios.

Knowledge and perceptions of pharmacogenomics among pharmacists in Manitoba, Canada.

This work was designed to describe the knowledge and perceptions of pharmacogenomics (PGx) among pharmacists in the Canadian province of Manitoba. A 40-item, web-based survey was distributed to pharmacists in Manitoba. Of 74 participants, one third had some education or training in PGx, and 12.

Impact of Cytochrome P450 Genetic Variation on Patient-Reported Symptom Improvement and Side Effects Among Children and Adolescents Treated with Fluoxetine.

Clinical practice guidelines recommend the use of fluoxetine, a selective serotonin reuptake inhibitor (SSRI), as a first-line pharmacotherapy for major depressive disorder (MDD) and obsessive compulsive disorder (OCD) in children and adolescents. However, response and tolerability to fluoxetine varies from child to child, which may in part, be a result of interindividual differences in fluoxetine metabolism. In this study, we examined whether genotype-predicted activity scores of cytochrome P450 enzymes were associated with patient-reported symptom improvement and side effects in children and adolescents treated with fluoxetine.

Pharmacogenomic allele coverage of genome-wide genotyping arrays: a comparative analysis.

The use of genome-wide genotyping arrays in pharmacogenomics (PGx) research and clinical implementation applications is increasing but it is unclear which arrays are best suited for these applications. Here, we conduct a comparative coverage analysis of PGx alleles included on genome-wide genotyping arrays, with an emphasis on alleles in genes with PGx-based prescribing guidelines. Genomic manifest files for seven arrays including the Axiom Precision Medicine Diversity Array (PMDA), Axiom PMDA Plus, Axiom PangenomiX, Axiom PangenomiX Plus, Infinium Global Screening Array, Infinium Global Diversity Array (GDA) and Infinium GDA with enhanced PGx (GDA-PGx) Array, were evaluated for coverage of 523 star alleles across 19 pharmacogenes included in prescribing guidelines developed by the Clinical Pharmacogenetic Implementation Consortium and Dutch Pharmacogenomics Working Group.

Predictors of the placebo response in a nutraceutical randomized controlled trial for depression.

Objective: The placebo response in depression studies is the change in symptoms amongst those who receive an inactive treatment. Many well-designed randomized controlled trials (RCTs) of depression have a high proportion of placebo responders, with little understanding as to why. The present study assesses characteristics associated with the placebo response in a nutraceutical trial with a large proportion of placebo responders.

Virtual twins for model-informed precision dosing of clozapine in patients with treatment-resistant schizophrenia.

Model-informed precision dosing using virtual twins (MIPD-VTs) is an emerging strategy to predict target drug concentrations in clinical practice. Using a high virtualization MIPD-VT approach (Simcyp version 21), we predicted the steady-state clozapine concentration and clozapine dosage range to achieve a target concentration of 350 to 600 ng/mL in hospitalized patients with treatment-resistant schizophrenia (N = 11). We confirmed that high virtualization MIPD-VT can reasonably predict clozapine concentrations in individual patients with a coefficient of determination (R ) ranging between 0.

Neuroimaging Insights: Kava's () Effect on Dorsal Anterior Cingulate Cortex GABA in Generalized Anxiety Disorder.

Generalised Anxiety Disorder (GAD) is a prevalent, chronic mental health disorder. The measurement of regional brain gamma-aminobutyric acid (GABA) offers insight into its role in anxiety and is a potential biomarker for treatment response. Research literature suggests (Kava) is efficacious as an anxiety treatment, but no study has assessed its effects on central GABA levels.

Interleukin 10 (IL10) promoter region polymorphism is associated with IL10 serum concentrations and processing speed in healthy community-dwelling older adults.

Inflammation is repressed by interleukin 10 (IL10), a potent anti-inflammatory cytokine, and unchecked inflammation can have detrimental effects on cognition. In healthy older adults enrolled in the Australian Research Council Longevity Intervention (ARCLI) cohort we explored whether a known functional single nucleotide polymorphism (SNP) in the promoter region of IL10, -1082 G/A (rs1800896), was associated with reaction times on computerized cognitive testing that included elements of processing speed (i.e.

and Variant Coverage of Commercial Antidepressant Pharmacogenomic Testing Panels Available in Victoria, Australia.

Pharmacogenomic (PGx) testing to inform antidepressant medication selection and dosing is gaining attention from healthcare professionals, patients, and payors in Australia. However, there is often uncertainty regarding which test is most suitable for a particular patient. Here, we identified and evaluated the coverage of and variants in commercial antidepressant PGx testing panels in Victoria, a large and ethnically diverse state of Australia.

The cellular mechanism of antipsychotic-induced myocarditis: A systematic review.

Antipsychotic drug-induced myocarditis is a serious and potentially fatal adverse drug reaction characterized by inflammation of the heart muscle (myocardium) that typically develops within the first month after commencing an antipsychotic drug. Although the precise mechanism of this severe adverse drug reaction is unknown, multiple theories have been proposed with varying levels of support from cellular or animal studies. We conducted a systematic review, in accordance with PRISMA guidelines, of published preclinical and clinical studies investigating the cellular mechanism by which antipsychotic drugs induce myocarditis.

The emergence, implementation, and future growth of pharmacogenomics in psychiatry: a narrative review.

Psychotropic medication efficacy and tolerability are critical treatment issues faced by individuals with psychiatric disorders and their healthcare providers. For some people, it can take months to years of a trial-and-error process to identify a medication with the ideal efficacy and tolerability profile. Current strategies (e.

Effect of kava (Piper methysticum) on peripheral gene expression among individuals with generalized anxiety disorder: A post hoc analysis of a randomized controlled trial.

Kava is a South Pacific plant-based medicine with anxiolytic properties, but little is known about the impact kava has on gene expression or whether gene expression can serve as a marker of kava response. This study aimed to determine whether kava treatment alters the expression of genes with physiological relevance to anxiety pathophysiology and whether the baseline expression of these physiologically relevant genes modifies the efficacy of kava treatment. In this post hoc analysis, we examined the expression of 48 genes relevant to the pathophysiology of anxiety collected from a double-blind randomized controlled trial that assessed the efficacy of kava treatment in generalized anxiety disorder.

PharmVar Tutorial on CYP2D6 Structural Variation Testing and Recommendations on Reporting.

The Pharmacogene Variation Consortium (PharmVar) provides nomenclature for the highly polymorphic human CYP2D6 gene locus and a comprehensive summary of structural variation. CYP2D6 contributes to the metabolism of numerous drugs and, thus, genetic variation in its gene impacts drug efficacy and safety. To accurately predict a patient's CYP2D6 phenotype, testing must include structural variants including gene deletions, duplications, hybrid genes, and combinations thereof.

Association of clozapine treatment and rate of methamphetamine or amphetamine relapses and abstinence among individuals with concurrent schizophrenia spectrum and amphetamine use disorder: A retrospective cohort study.

Background: Preliminary evidence suggest clozapine is associated with more favorable impact on concurrent substance use disorder related outcomes in patients with concurrent schizophrenia spectrum disorders (SSD). At the same time, there is a dearth of evidence with regards to clozapine outcomes in the context of concurrent methamphetamine or amphetamine use disorder (MAUD).

Aims: To examine whether clozapine use decreases rate of methamphetamine or amphetamine (MA) relapses and increases the likelihood of maintaining abstinence from any MA use.

Pharmacomicrobiomics of Antidepressants in Depression: A Systematic Review.

This systematic review evaluated the animal and human evidence for pharmacomicrobiomics (PMx) interactions of antidepressant medications. Studies of gut microbiota effects on functional and behavioral effects of antidepressants in human and animal models were identified from PubMed up to December 2022. Risk of bias was assessed, and results are presented as a systematic review following PRISMA guidelines.