Publications by authors named "Masaru Tsukahara"
Rationale: Clozapine, the standard treatment for treatment-resistant schizophrenia (TRS), is generally recommended in a multiple-daily dosing regimen. However, it is commonly administered once daily in clinical practice. Few studies have compared the longitudinal clinical outcomes of these two dosing regimens.
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- In Japan, the treatment of schizophrenia has historically involved polypharmacy, which is less common globally, and this issue persisted until the introduction of clozapine in 2009.
- A study examining changes in psychopharmacotherapy over 12 years revealed significant reductions in average medication doses and a notable increase in antipsychotic monotherapy following the introduction of clozapine.
- By 2020, the prescription of clozapine rose to 37.3%, contributing to a decline in the use of multiple antipsychotics, indicating that clozapine could optimize schizophrenia treatment in Japan.
Introduction: No study has investigated the impact of smoking habits and concomitant valproic acid (VPA) use on clinical outcomes in maintenance treatment with clozapine. Thus, we aimed to examine the effect of smoking habits and concomitant VPA use on relapse during the first year after discharge in patients with treatment-resistant schizophrenia (TRS) receiving clozapine.
Methods: This retrospective cohort study included patients with TRS who were initiated on clozapine during hospitalization and discharged between April 2012 and January 2021 in two tertiary psychiatric hospitals in Japan.
This retrospective cohort study aimed to investigate the longitudinal changes in clozapine dose over a 5-year period in patients with treatment-resistant schizophrenia (TRS). Patients with TRS who were administered clozapine at a hospital between April 2012 and December 2016 and continued treatment with clozapine for at least 1 year were included. Clozapine doses were compared at the dose-fixation point, defined as when the same regimen of clozapine had been continued for 8 weeks or longer, and the post-dose-fixation phase, at 12, 36 and 60 months after clozapine initiation.
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- A study examined how smoking cessation affects plasma clozapine levels in Japanese inpatients with schizophrenia, as prior research mainly focused on Caucasian populations.
- The research included a review of 14 patients who were treated with clozapine and monitored before and after a smoking ban at their hospital.
- Results showed a significant increase in plasma clozapine levels by 53.2%, leading to some patients experiencing serious side effects, indicating the need for careful monitoring and possible dose adjustments after quitting smoking.
Article Synopsis
- This international guideline suggests enhancing clozapine package inserts by implementing ancestry-based dosing and titration to reduce adverse drug reactions (ADRs).
- Clozapine, a powerful medication, has a narrow therapeutic range and is highly associated with toxicity, especially in certain populations; it is especially risky due to its high rates of pneumonia-related mortality.
- The guideline outlines six personalized dosing schedules based on ancestry and metabolic activity, recommending varying daily doses of clozapine tailored to individual patient profiles to minimize the risk of ADRs.
Objective: Clozapine is generally recommended to be prescribed in a divided dosing regimen based on its relatively short plasma half-life. However, there has been little evidence to support the superiority of divided dosing of clozapine over once-daily dosing. To our knowledge, there have been no studies examining differences in actual plasma concentrations or adverse effects between the 2 dosing strategies of clozapine.
View Article and Find Full Text PDFSlow titration of clozapine is recommended given the risk of serious adverse effects. However, the utility and safety of slower-than-recommended titration of clozapine remain unclear. Consequently, we aimed to investigate the clinical utility and safety of slower-than-recommended titration of clozapine for treatment-resistant schizophrenia.
View Article and Find Full Text PDFRationale: In the antipsychotic treatment of schizophrenia with little medication history, especially in drug-naïve cases, predictors of side effects are important. However, predictors of antipsychotic-induced akathisia remain unclear.
Objectives: This study aimed to investigate the incidence and predictors of acute akathisia in severely ill patients with first-episode schizophrenia spectrum disorders (FES).
Background: Sex chromosomes of extant eutherian species are too ancient to reveal the process that initiated sex-chromosome differentiation. By contrast, the neo-sex chromosomes generated by sex-autosome fusions of recent origin in Tokudaia muenninki are expected to be evolutionarily 'young', and therefore provide a good model in which to elucidate the early phases of eutherian sex chromosome evolution. Here we describe the genomic evolution of T.
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