Update Lessons from Positron Emission Tomography Imaging Part I: A Systematic Critical Review on Therapeutic Plasma Concentrations of Antipsychotics.

BACKGROUND: Positron emission tomography (PET) and single photon emission tomography (SPECT) of molecular drug targets (neuroreceptors and transporters) provide essential information for therapeutic drug monitoring-guided antipsychotic drug therapy. The optimal therapeutic windows for D 2 antagonists and partial agonists, as well as their proposed target ranges, are discussed based on an up-to-date literature search. METHODS: This part I of II presents an overview of molecular neuroimaging studies in humans and primates involving the target engagement of amisulpride, haloperidol, clozapine, aripiprazole, olanzapine, quetiapine, risperidone, cariprazine, and ziprasidone. The systemic review particularly focused on dopamine D 2 -like and 5-HT 2A receptors. Target concentration ranges were estimated based on receptor occupancy ranges that relate to clinical effects or side effects (ie, extrapyramidal side effects). In addition, findings for other relevant receptor systems were included to further enrich the discussion. RESULTS: The reported reference ranges for aripiprazole and clozapine align closely with findings from PET studies. Conversely, for haloperidol, risperidone, and olanzapine, the PET studies indicate that a lowering of the previously published upper limits would be necessary to decrease the risk of extrapyramidal side effect. CONCLUSIONS: Molecular neuroimaging studies serve as a strong tool for defining target ranges for antipsychotic drug treatment and directing therapeutic drug monitoring.

Update Lessons from PET Imaging Part II: A Systematic Critical Review on Therapeutic Plasma Concentrations of Antidepressants.

BACKGROUND: Compared with antipsychotics, the relationship between antidepressant blood (plasma or serum) concentrations and target engagement is less well-established. METHODS: We have discussed the literature on the relationship between plasma concentrations of antidepressant drugs and their target occupancy. Antidepressants reviewed in this work are citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine, sertraline, venlafaxine, duloxetine, milnacipran, tricyclic antidepressants (amitriptyline, nortriptyline, and clomipramine), bupropion, tranylcypromine, moclobemide, and vortioxetine. Four electronic databases were systematically searched. RESULTS: We included 32 articles published 1996-2022. A strong relationship between serotonin transporter (SERT) occupancy and drug concentration is well established for selective serotonin reuptake inhibitors. Lower limits of recommended therapeutic reference ranges largely corroborate with the findings from positron emission tomography studies (80% SERT occupancy). Only a few novel studies have investigated alternative targets, that is, norepinephrine transporters (NETs), dopamine transporters (DATs), or monoamine oxidase A (MAO-A). For certain classes of drugs, positron emission tomography study data are inconclusive. Low DAT occupancy after bupropion treatment speculates its discussed mechanism of action. For MAO inhibitors, a correlation between drug concentration and MAO-A occupancy could not be established. CONCLUSIONS: Neuroimaging studies are critical in TDM-guided therapy for certain antidepressants, whereas for bupropion and MAO inhibitors, the available evidence offers no further insight. Evidence for selective serotonin reuptake inhibitors is strong and justifies a titration toward suggested ranges. For SNRIs, duloxetine, and venlafaxine, NETs are sufficiently occupied, well above the SERT efficacy threshold. For these drugs, a titration toward higher concentrations (within the recommended range) should be considered in case of no response at lower concentrations.

Caution for psychiatrists: malignant hyperthermia risks with the anesthetic agent succinylcholine (Suxamethonium) during electroconvulsive therapy.

BACKGROUND: Malignant hyperthermia is a potentially lethal condition triggered by specific anesthetic drugs, especially a depolarizing muscle relaxant of succinylcholine (Suxamethonium). Despite the frequent use of succinylcholine with electroconvulsive therapy (ECT), there has been no reported case of potentially lethal malignant hyperthermia following ECT. In addition, the time interval between the administration of succinylcholine and the onset of malignant hyperthermia has not been outlined in the context of ECT. CASE PRESENTATION: We present the case of a 79-year-old woman suffering from severe depression, who experienced severe malignant hyperthermia due to succinylcholine administration during an ECT session. She presented with a high fever of 40.2 °C, tachycardia of 140/min, hypertension with a blood pressure exceeding 200 mmHg, significant muscle rigidity, and impaired consciousness. These symptoms emerged two hours after ECT, which occurred in a psychiatric ward rather than an operating room, and reached their peak in less than 24 h. She was given 60 mg of dantrolene, which quickly reduced the muscular rigidity. Subsequently, she received two additional doses of 20 mg and 60 mg of dantrolene, which brought her fever down to 36.2 °C and completely eased her muscle rigidity within two days after ECT. CONCLUSIONS: This is the first reported case of potentially lethal malignant hyperthermia after ECT. In addition, it highlights the delayed onset of malignant hyperthermia following an ECT procedure, emphasizing the necessity for psychiatrists to recognize its onset even after the treatment. In the light of potentially lethal consequences of malignant hyperthermia, it is critically important for psychiatrists to closely monitor both intraoperative and postoperative patient's vital signs and characteristic physical presentations, promptly identify any symptomatic emergence, and treat it immediately with dantrolene.

Unraveling the Influence of Age, IQ, Education, and Negative Symptoms on Neurocognitive Performance in Schizophrenia: A Conditional Inference Tree Analysis.

INTRODUCTION: The complex nature of neurocognitive impairment in schizophrenia has been discussed in light of the mixed effects of antipsychotic drugs, psychotic symptoms, dopamine D2 receptor blockade, and intelligence quotient (IQ). These factors have not been thoroughly examined before. METHODS: This study conducted a comprehensive re-analysis of the CATIE data using machine learning techniques, in particular Conditional Inference Tree (CTREE) analysis, to investigate associations between neurocognitive functions and moderating factors such as estimated trough dopamine D2 receptor blockade with risperidone, olanzapine, or ziprasidone, Positive and Negative Syndrome Scale (PANSS), and baseline IQ in 573 patients with schizophrenia. RESULTS: The study reveals that IQ, age, and education consistently emerge as significant predictors across all neurocognitive domains. Furthermore, higher severity of PANSS-negative symptoms was associated with lower cognitive performance scores in several domains. CTREE analysis, in combination with a genetic algorithm approach, has been identified as particularly insightful for illustrating complex interactions between variables. Lower neurocognitive function was associated with factors such as age>52 years, IQ<94/95,<12/13 education years, and more pronounced negative symptoms (score<26). CONCLUSIONS: These findings emphasize the multifaceted nature of neurocognitive functioning in patients with schizophrenia, with the PANSS-negative score being an important predictor. This gives rise to a role in addressing negative symptoms as a therapeutic objective for enhancing cognitive impairments in these patients. Further research must examine nonlinear relationships among various moderating factors identified in this work, especially the role of D2 occupancy.

Advancements in Non-Dopaminergic Treatments for Schizophrenia: A Systematic Review of Pipeline Developments.

INTRODUCTION: Conventional antipsychotic drugs that attenuate dopaminergic neural transmission are ineffective in approximately one-third of patients with schizophrenia. This necessitates the development of non-dopaminergic agents. METHODS: A systematic search was conducted for completed phase II and III trials of compounds for schizophrenia treatment using the US Clinical Trials Registry and the EU Clinical Trials Register. Compounds demonstrating significant superiority over placebo in the primary outcome measure in the latest phase II and III trials were identified. Collateral information on the included compounds was gathered through manual searches in PubMed and press releases. RESULTS: Sixteen compounds were identified; four compounds (ulotaront, xanomeline/trospium chloride, vabicaserin, and roluperidone) were investigated as monotherapy and the remaining 12 (pimavanserin, bitopertin, BI 425809, encenicline, tropisetron, pregnenolone, D-serine, estradiol, tolcapone, valacyclovir, cannabidiol, and rimonabant) were examined as add-on therapy. Compared to the placebo, ulotaront, xanomeline/trospium chloride, vabicaserin, bitopertin, estradiol, cannabidiol, rimonabant, and D-serine showed efficacy for positive symptoms; roluperidone and pimavanserin were effective for negative symptoms; and encenicline, tropisetron, pregnenolone, tolcapone, BI 425809, and valacyclovir improved cognitive function. DISCUSSION: Compounds that function differently from existing antipsychotics may offer novel symptom-specific therapeutic strategies for patients with schizophrenia.

Comparable Psychotropic Prescription Rates After Hospital Discharge Between Patients with COVID-19 and Those With Non-COVID-19-Related Respiratory Infection.

INTRODUCTION: Whether psychiatric symptoms after recovery from coronavirus disease 2019 (COVID-19) are specific to this illness remains unclear. METHODS: In this retrospective study, the Diagnosis Procedure Combination data and outpatient clinic data were used for patients who received inpatient treatment in Saiseikai-affiliated hospitals for COVID-19 or other respiratory tract infections (non-COVID) from 2020 to 2022. The primary outcome was new prescriptions of psychotropic drugs after discharge (i. e., prescriptions of psychotropics to patients who had not received them before or during their hospitalization). Values of interest were compared between groups using the chi-square test or Fisher's exact test. A COX proportional-hazards model was used to examine factors associated with psychotropic prescriptions after discharge in age- and sex-matched COVID-19 and non-COVID patients. RESULTS: Of 31,993 chart records, 19,613 were excluded due to a positive history with psychiatric disorders (n=2,445), prescriptions of psychotropics (n=744), and no follow-ups (n=16,424). Thus, 3,648 COVID-19 and 8,732 non-COVID patients were included (mean [range] duration of follow-up, days: 146.9 [1-727] and 239.2 [1-729], respectively). Two hundred and four (5.6%) of the 3,648 patients with COVID-19 received psychotropic prescriptions after discharge. No statistically significant differences were observed in the prescription rates of any psychotropic category between the COVID-19 and non-COVID groups. An increase in severity during hospitalization was significantly associated with more frequent psychotropic prescriptions (hazard ratio 1.83, p<0.001). DISCUSSION: The development of psychiatric symptoms should be closely observed, especially in patients who experienced increased severity during hospitalization, regardless of whether they suffered from COVID-19.

Factors Associated with Antidepressant Effects of Ketamine: A Reanalysis of Double-Blind Randomized Placebo-Controlled Trial of Intravenous Ketamine for Treatment-Resistant Depression.

INTRODUCTION: Predictors of treatment response to intravenous ketamine remain unclear in patients with treatment-resistant depression (TRD); therefore, this study aimed to clarify these predictors using the US National Institutes of Health database of clinical trials. METHODS: Data from a placebo-controlled, double-blind, randomized controlled trial were used to assess the efficacy of intravenous ketamine in adult patients with TRD (NCT01920555). For the analysis, data were used from the participants who had received therapeutic doses of intravenous ketamine (i. e., 0.5 and 1.0 mg/kg). Logistic and multivariable regression analyses were conducted to explore the demographic and clinical factors associated with response to treatment or changes in the Hamilton Depression Rating Scale 6 items (HAM-D-6) total score. RESULTS: This study included 31 patients with TRD (13 women; mean±standard deviation age, 48.4±10.9 years). Logistic regression analysis showed that the age of onset was positively correlated with treatment response after three days of ketamine administration (ß=0.08, p=0.037); however, no association was observed between treatment response and age, sex, baseline HAM-D-6 total score, or dissociative score assessed with the Clinician-Administered Dissociative States Scale 40 min after ketamine infusion. Multiple regression analysis showed that no factors were correlated significantly with the percentage change in the HAM-D-6 total score three days after ketamine administration. DISCUSSION: Later disease onset correlates with a better treatment response three days after ketamine infusion in patients with TRD. Glutamatergic signal transmission may be impaired in patients with an earlier onset of depression, resulting in decreased neuroplasticity, which diminishes ketamine response.

Reliability of the Two-dimensional Mood Scale for self-reported mood assessment by older adults with dementia.

The purpose of this study was to evaluate the reliability of the Two-dimensional Mood Scale (TDMS) for mood assessment among older adults with dementia. The study included 100 elderly patients with dementia admitted to two hospitals. For each mood state measured by the TDMS, the intraclass correlation coefficient of agreement (ICCagreement) was calculated to evaluate test-retest reliability. Scores corresponding to the minimal detectable change (MDC) in each mood state at the individual level (MDCind) was also calculated to evaluate measurement error, while McDonald's omega was calculated to evaluate internal consistency. The TDMS ICC was 0.54 for vitality, 0.74 for stability, 0.70 for pleasure, and 0.55 for arousal. The MDCind was 6.89 for vitality, 5.88 for stability, 9.96 for pleasure, and 4.11 for arousal. McDonald's omega ranged from 0.60 to 0.84. The TDMS has generally acceptable reliability for the self-assessment of mood states by older adults with dementia.

Trends and future projections of cervical cancer-related outcomes in Japan: What happens if the HPV vaccine program is not implemented?

Contrary to other developed countries, in Japan, recent years have seen increases in cervical cancer incidence and mortality among young people. However, the human papillomavirus (HPV) vaccine program, a key measure for avoiding cervical cancer, has been virtually suspended. Temporal changes in cervical cancer profiles in this unique situation have not been fully investigated epidemiologically. Our study aimed to determine the current status and future trends of the incidence and mortality of cervical cancer and precancerous lesions in Japan. Mortality rates of cervical cancer during 1975 to 2016 and incidence rates of cervical cancer and cervical intraepithelial neoplasia (CIN) 3 during 1975 to 2013 were examined using vital statistics and population-based cancer registry data in Japan. Bayesian age-period-cohort analyses were performed to analyze temporal changes of the three cervical cancer-related outcomes. We also calculated projections to 2028 for the three outcomes, assuming that HPV vaccination coverage and screening rates in Japan would be maintained at the current level after the resumption of the national vaccination program. The risk of occurrence of the three outcomes showed similar changes by birth cohort, peaking in the mid-1890s to 1900s birth cohorts, declining sharply in the 1940s birth cohort, and persistently increasing in the 1950s and later birth cohorts. Projections to 2028 show increases in cervical cancer incidence and mortality in the 30 to 69 age group, with a particular increase in CIN3 incidence in the 25 to 49 age group, if HPV vaccine programs and screening are not effectively implemented. These findings revealed an increasing cervical disease burden among reproductive age females in Japan.

Dopaminergic dysfunction and excitatory/inhibitory imbalance in treatment-resistant schizophrenia and novel neuromodulatory treatment.

Antipsychotic drugs are the mainstay in the treatment of schizophrenia. However, one-third of patients do not show adequate improvement in positive symptoms with non-clozapine antipsychotics. Additionally, approximately half of them show poor response to clozapine, electroconvulsive therapy, or other augmentation strategies. However, the development of novel treatment for these conditions is difficult due to the complex and heterogenous pathophysiology of treatment-resistant schizophrenia (TRS). Therefore, this review provides key findings, potential treatments, and a roadmap for future research in this area. First, we review the neurobiological pathophysiology of TRS, particularly the dopaminergic, glutamatergic, and GABAergic pathways. Next, the limitations of existing and promising treatments are presented. Specifically, this article focuses on the therapeutic potential of neuromodulation, including electroconvulsive therapy, repetitive transcranial magnetic stimulation, transcranial direct current stimulation, and deep brain stimulation. Finally, we propose multivariate analyses that integrate various perspectives of the pathogenesis, such as dopaminergic dysfunction and excitatory/inhibitory imbalance, thereby elucidating the heterogeneity of TRS that could not be obtained by conventional statistics. These analyses can in turn lead to a precision medicine approach with closed-loop neuromodulation targeting the detected pathophysiology of TRS.

Glutamatergic and GABAergic metabolite levels in schizophrenia-spectrum disorders: a meta-analysis of 1H-magnetic resonance spectroscopy studies.

BACKGROUND: The glutamate (Glu) and gamma aminobutyric acid (GABA) hypotheses of schizophrenia were proposed in the 1980s. However, current findings on those metabolite levels in schizophrenia have been inconsistent, and the relationship between their abnormalities and the pathophysiology of schizophrenia remains unclear. To summarize the nature of the alterations of glutamatergic and GABAergic systems in schizophrenia, we conducted meta-analyses of proton magnetic resonance spectroscopy (1H-MRS) studies examining these metabolite levels. METHODS: A systematic literature search was conducted using Embase, Medline, PsycINFO, and PubMed. Original studies that compared four metabolite levels (Glu, glutamine [Gln], Glx [Glu+Gln], and GABA), as measured by 1H-MRS, between individuals at high risk for psychosis, patients with first-episode psychosis, or patients with schizophrenia and healthy controls (HC) were included. A random-effects model was used to calculate the effect sizes for group differences in these metabolite levels of 18 regions of interest between the whole group or schizophrenia group and HC. Subgroup analysis and meta-regression were performed based on the status of antipsychotic treatment, illness stage, treatment resistance, and magnetic field strength. RESULTS: One-hundred-thirty-four studies met the eligibility criteria, totaling 7993 participants with SZ-spectrum disorders and 8744 HC. 14 out of 18 ROIs had enough numbers of studies to examine the group difference in the metabolite levels. In the whole group, Glx levels in the basal ganglia (g = 0.32; 95% CIs: 0.18-0.45) were elevated. Subgroup analyses showed elevated Glx levels in the hippocampus (g = 0.47; 95% CIs: 0.21-0.73) and dorsolateral prefrontal cortex (g = 0.25; 95% CIs: 0.05-0.44) in unmedicated patients than HC. GABA levels in the MCC were decreased in the first-episode psychosis group compared with HC (g = -0.40; 95% CIs: -0.62 to -0.17). Treatment-resistant schizophrenia (TRS) group had elevated Glx and Glu levels in the MCC (Glx: g = 0.7; 95% CIs: 0.38-1.01; Glu: g = 0.63; 95% CIs: 0.31-0.94) while MCC Glu levels were decreased in the patient group except TRS (g = -0.17; 95% CIs: -0.33 to -0.01). CONCLUSIONS: Increased glutamatergic metabolite levels and reduced GABA levels indicate that the disruption of excitatory/inhibitory balance may be related to the pathophysiology of schizophrenia-spectrum disorders.

Clinicopathologic analysis of pineal parenchymal tumors of intermediate differentiation: a multi-institutional cohort study by the Kyushu Neuro-Oncology Study Group.

PURPOSE: Pineal parenchymal tumors of intermediate differentiation (PPTIDs), which were recognized in the 2007 World Health Organization (WHO) classification, are rare, accounting for less than 1% of all central nervous system tumors. This rarity and novelty complicate the diagnosis and treatments of PPTID. We therefore aimed to evaluate the clinicopathological significance of this tumor. METHODS: At 11 institutions participating in the Kyushu Neuro-Oncology Study Group, data for patients diagnosed with PPTID were collected. Central pathology review and KBTBD4 mutation analysis were applied to attain the diagnostically accurate cohort. RESULTS: PPTID was officially diagnosed in 28 patients: 11 (39%) with WHO grade 2 and 17 (61%) with WHO grade 3 tumors. Median age was 49 years, and the male:female ratio was 1:2.1. Surgery was attempted in all 28 patients, and gross total resection (GTR) was achieved in 46% (13/28). Adjuvant radiotherapy and chemotherapy were administered to, respectively, 82% (23/28) and 46% (13/28). The 5-year progression-free survival (PFS) and overall survival rates were 64.9% and 70.4% respectively. Female sex (p = 0.018) and GTR (p < 0.01) were found to be independent prognostic factors for PFS and female sex (p = 0.019) was that for OS. Initial and second recurrences were most often leptomeningeal (67% and 100% respectively). 80% (20/25) of patients harbored a KBTBD4 mutation. CONCLUSIONS: Female sex and GTR were independent prognostic factors in our patients with PPTID. Leptomeningeal recurrence was observed to be particularly characteristic of this tumor. The rate of KBTBD4 mutation observed in our cohort was acceptable and this could prove the accuracy of our PPTID cohort.

Antipsychotic Monotherapy for Major Depressive Disorder: A Systematic Review and Meta-Analysis.

Although several randomized controlled trials (RCTs) have compared the effectiveness, efficacy, and safety of antipsychotic monotherapy (APM) versus placebo in patients with major depressive disorder (MDD), no meta-analysis has examined this topic. We conducted a systematic literature search using MEDLINE and Embase to identify relevant RCTs and performed a meta-analysis to compare the following outcomes between APM and placebo: response and remission rates, study discontinuation due to all causes, lack of efficacy, and adverse events, changes in total scores on depression severity scales, and individual adverse event rates. A total of 13 studies were identified, with 14 comparisons involving 3,197 participants that met the eligibility criteria. There were significant differences between APM and placebo in response and remission rates and changes in the primary depression severity scale in favor of APM, and study discontinuation due to adverse events and several individual adverse events in favor of placebo. No significant difference was observed in discontinuation due to all causes. APM could have antidepressant effects in the acute phase of MDD, although clinicians should be aware of an increased risk of some adverse events.

Trazodone and Mianserin for Delirium: A Retrospective Chart Review.

BACKGROUND: Although antipsychotics are commonly used for delirium, their adverse effects are a serious concern in light of extrapyramidal symptoms and cardiovascular disturbances. In clinical practice, sedative antidepressants are frequently used as an alternative treatment for delirium; however, there is scarce evidence. Thus, we conducted a retrospective chart review to examine the use and effectiveness of trazodone and mianserin for delirium. METHODS: Patients who were admitted to a university hospital during 4 years and received either trazodone or mianserin on a regular schedule as monotherapy for the treatment of delirium were included. The rates of and times to the improvement of delirium were compared. RESULTS: Among 3971 patients who developed delirium, 379 (9.5%) and 341 (8.6%) patients received trazodone and mianserin on a regular schedule; 52 and 46 patients met the eligibility criteria (ie, monotherapy) for trazodone and mianserin, respectively. The percentages of patients 65 years or older were 86.5% (n = 45) for trazodone and 89.1% (n = 41) for mianserin. The rates of the improvement of delirium were 63.5% for trazodone and 50.0% for mianserin. Times to the improvement of delirium were 5.3 days (95% confidence interval, 3.2-7.4 days) for trazodone and 9.3 days (95% confidence interval, 5.3-13.3 days) for mianserin. There were no significant differences in the primary outcomes between the 2 groups ( P = 0.17 and P = 0.13, respectively). CONCLUSION: Considering potentially serious, sometimes lethal, adverse effects of antipsychotics, sedative antidepressants such as trazodone and mianserin may be a treatment option for delirium, especially in the elderly.

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

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

Investigating structural subdivisions of the anterior cingulate cortex in schizophrenia, with implications for treatment resistance and glutamatergic levels.

BACKGROUND: Abnormalities in the anterior cingulate cortex (ACC) are thought to play an important role in the pathophysiology of schizophrenia. Given regional variations in ACC structure, the present study aimed to examine ACC structural subdivisions and their relationships to treatment resistance and glutamatergic levels in schizophrenia. METHODS: This study included 100 patients with schizophrenia and 52 healthy controls from 2 cohorts. We applied non-negative matrix factorization to identify accurate and stable spatial components of ACC structure. Between groups, we compared ACC structural indices in each spatial component based on treatment resistance or response and tested relationships with ACC glutamate + glutamine levels. RESULTS: We detected reductions in cortical thickness and increases in mean diffusivity in the spatial components on the surface of the cingulate sulcus, especially in patients with treatment-resistant and clozapine-resistant schizophrenia. Notably, mean diffusivity in these components was higher in patients who did not respond to clozapine compared to those who did. Furthermore, these ACC structural alterations were related to elevated ACC glutamate + glutamine levels but not related to symptomatology or antipsychotic dose. LIMITATIONS: Sample sizes, cross-sectional findings and mixed antipsychotic status were limitations of this study. CONCLUSION: This study identified reproducible abnormalities in ACC structures in patients with treatment-resistant and clozapine-resistant schizophrenia. Given that these spatial components play a role in inhibitory control, the present study strengthens the notion that glutamate-related disinhibition is a common biological feature of treatment resistance in schizophrenia.

MAP Bayesian modelling combining striatal dopamine receptor occupancy and plasma concentrations to optimize antipsychotic dose regimens in individual patients.

AIMS: Develop a robust and user-friendly software tool for the prediction of dopamine D2 receptor occupancy (RO) in patients with schizophrenia treated with either olanzapine or risperidone, in order to facilitate clinician exploration of the impact of treatment strategies on RO using sparse plasma concentration measurements. METHODS: Previously developed population pharmacokinetic models for olanzapine and risperidone were combined with a pharmacodynamic model for D2 RO and implemented in the R programming language. Maximum a posteriori Bayesian estimation was used to provide predictions of plasma concentration and RO based on sparse concentration sampling. These predictions were then compared to observed plasma concentration and RO. RESULTS: The average (standard deviation) response times of the tools, defined as the time required for the application to predict parameter values and display the output, were 2.8 (3.1) and 5.3 (4.3) seconds for olanzapine and risperidone, respectively. The mean error (95% confidence interval) and root mean squared error (95% confidence interval) of predicted vs. observed concentrations were 3.73 ng/mL (-2.42-9.87) and 10.816 ng/mL (6.71-14.93) for olanzapine, and 0.46 ng/mL (-4.56-5.47) and 6.68 ng/mL (3.57-9.78) for risperidone and its active metabolite (9-OH risperidone). Mean error and root mean squared error of RO were -1.47% (-4.65-1.69) and 5.80% (3.89-7.72) for olanzapine and -0.91% (-7.68-5.85) and 8.87% (4.56-13.17) for risperidone. CONCLUSION: Our monitoring software predicts concentration-time profiles and the corresponding D2 RO from sparsely sampled concentration measurements in an accessible and accurate form.

Novel Antidepressants in the Pipeline (Phase II and III): A Systematic Review of the US Clinical Trials Registry.

INTRODUCTION: There is an imminent need for faster-acting and more effective antidepressants beyond the monoaminergic hypothesis. METHODS: We systematically searched the US Clinical Trials registry for antidepressant compounds with completed phase II and III trials. Compounds that demonstrated significant superiority over placebo in the primary outcome measure in the latest phase of phase II and III trials were identified. The collateral information was gathered via a PubMed search and press releases. RESULTS: Nine compounds were identified. AXS-05 (a combination of dextromethorphan and bupropion) and ansofaxine hydrochloride showed a positive result over placebo in a phase III study for major depressive disorder or treatment-resistant depression. MIJ821, nitrous oxide, psilocybin, ayahuasca, facial injection of botulinum toxin A, prasterone, and casopitant demonstrated at least one positive result in phase II trials. Ayahuasca showed a greater response rate than placebo at week one, indicating the rapid antidepressant effect. DISCUSSION: These new compounds with novel mechanisms of action are expected to provide a greater variety of treatment options for depression if preliminary positive results are confirmed.

Drug Combinations for Mood Disorders and Physical Comorbidities That Need Attention: A Cross-Sectional National Database Survey.

INTRODUCTION: This study investigated combined prescriptions of drugs for mood disorders and physical comorbidities that need special attention in the light of frequent physical comorbidities in patients with mood disorders. METHODS: We used the claims sampling data of 581,990 outpatients in January 2015 from the National Database of Health Insurance Claims and Specific Health Checkups of Japan. Fisher's exact test was performed to compare the prescription rates of non-steroidal anti-inflammatory drugs (NSAIDs), loop/thiazide diuretics, angiotensin-converting enzyme inhibitors, and/or angiotensin II receptor blockers between lithium users and age- and sex-matched non-lithium users; NSAIDs, antiplatelet drugs, and/or anticoagulants between selective serotonin reuptake inhibitor (SSRI)/serotonin-noradrenaline reuptake inhibitor (SNRI) users and non-users; warfarin between mirtazapine users and non-users; and the proportions of patients in the two groups with a diagnosis of somatic conditions for which these medications were indicated and actually received them. A Bonferroni corrected p-value of<0.05/3 was considered statistically significant. RESULTS: Prescriptions of the above-mentioned medications were less frequent in lithium and mirtazapine users and comparable in SSRI/SNRI users, compared to non-users (18.3 vs. 31.9%, p=7.6×10-10; 0.78 vs. 1.65%, p=0.01; 23.1 vs. 24.1%, p=0.044). In a subgroup of patients with somatic diseases for which these medications were indicated, the prescription rates were comparable in lithium and mirtazapine users and higher in SSRI/SNRI users compared to non-users (28.0 vs. 29.4%, p=0.73; 4.7 vs. 7.4%, p=0.28; 35.6 vs. 33.4%, p=0.0026). DISCUSSION: Pharmacotherapy with drugs for mood disorders and physical comorbidities that require attention was commonly observed in clinical practice.

Clinical Outcomes after Clozapine Discontinuation in Patients with Schizophrenia: A Systematic Review.

INTRODUCTION: Clozapine is the gold standard of treatment for patients with treatment-resistant schizophrenia. However, approximately 60% of those patients do not respond to clozapine; moreover, clinical outcomes after clozapine discontinuation are unclear so far. Therefore, we conducted a systematic review to clarify the outcomes after clozapine discontinuation. METHODS: A systematic literature search was conducted, using MEDLINE and Embase with the following keywords: (clozapine AND (cessation* OR cease* OR withdraw* OR discontinu* OR halt* OR stop* OR switch*) AND (schizophreni* OR schizoaffective)). RESULTS: A total of 28 clinical studies from 27 articles were identified and included in this systematic review. Three randomized controlled trials reported worsening of psychiatric symptoms. In 10 single-arm studies, the results of worsening and improving psychiatric symptoms were inconsistent. In one large retrospective cohort study, clozapine rechallenge, olanzapine, and antipsychotic polypharmacy had lower rehospitalization rates compared to no medication after clozapine discontinuation. In the other 14 retrospective studies, the vast majority showed worsening of clinical status after clozapine discontinuation. Among five studies on clinical outcomes after clozapine rechallenge, four reported improvements in clinical status in more than half of patients who rechallenged clozapine. The remaining study reported that the clozapine discontinuation-rechallenge group had a worse remission assessment score than the clozapine discontinuation-no rechallenge group. DISCUSSION: Clinical outcomes generally worsen after clozapine discontinuation. Clozapine rechallenge and olanzapine may be considered following clozapine discontinuation. The outcomes after clozapine discontinuation in clozapine non-responders remain inconclusive; therefore, well-designed studies are warranted.