Mechanism of action of atypical antipsychotic drugs and the neurobiology of schizophrenia

Waterborne aripiprazole blunts the stress response in zebrafish

Here we provide, at least to our knowledge, the first evidence that aripiprazole (APPZ) in the water blunts the stress response of exposed fish in a concentration ten times lower than the concentration detected in the environment. Although the mechanism of APPZ in the neuroendocrine axis is not yet determined, our results highlight that the presence of APPZ residues in the environment may interfere with the stress responses in fish. Since an adequate stress response is crucial to restore fish homeostasis after stressors, fish with impaired stress response may have trouble to cope with natural and/or imposed stressors with consequences to their welfare and survival.

Prevalence of late potentials on signal-averaged ECG in patients with psychiatric disorders

BACKGROUND

Sudden cardiac death (SCD) occurs three times more often in psychiatric patients than in the general population. QRS fragmentation (QRSfr) and signal-averaged electrocardiography (SAECG) are simple, inexpensive, readily available tools for detecting the presence of abnormal depolarization and late potentials (LPs) in these patients, a result of either the underlying disease or treatment.

METHODS

Frequency of LP detection by SAECG and QRSfr was studied in 52 psychiatric patients and compared with 30 healthy (without known structural heart disease or occurrence of ventricular arrhythmia) controls. Patients were then prospectively followed up and incidence of SCD was recorded.

RESULTS

LP prevalence was significantly higher in patients than in controls (16/52-31% vs 2/30-7%, p=0.012), while QRSfr was similar between these two groups (p=0.09). Of the LP presence criteria, the root mean square value at terminal 40msec of the QRS (RMS40) was significantly lower in patients (32μV, SD=19μV, vs 46μV, SD=32μV, p=0.015). Among patients, no differences were noted between the LP positive and negative groups regarding age, sex, number of medications, class of antipsychotics and defined daily doses. Mean follow-up was 46months (SD=11) and during it 3 patients suffered SCD. Although 2 SCD victims had both LPs and QRSfr concurrently present, neither of them, nor their simultaneous presence could definitely account for the events.

CONCLUSIONS

LP prevalence in psychiatric patients was significantly higher than in controls. SAECG performance was feasible in all cases and constitutes a readily available tool for assessing myocardial electrophysiological alterations in this patient group.

Determination of antipsychotic drugs in hospital and wastewater treatment plant samples by gas chromatography/tandem mass spectrometry

The development and performance evaluation of a method for the simultaneous determination of six antipsychotic drugs in hospital effluents and wastewater treatment plants (WWTP) samples are herein presented. The method involves an off-line mixed mode (reversed-phase and strong cation exchange) solid phase extraction (SPE) with gas chromatography (GC) coupled to tandem mass spectrometry (MS/MS). The present methodology was validated following internationally accepted criteria, and the studied parameters included selectivity, linearity, limits of detection (LOD) and quantitation (LLOQ), instrumental limits, precision and accuracy, stability and recovery. The procedure was linear for concentrations ranging from 0.1 to 10μg/L (0.02 to 2μg/L for haloperidol), with determination coefficients higher than 0.99 for all analytes. Intra- and inter-day precision was lower than 15% for all analytes at the studied concentrations, while accuracy remained between a ±15% interval. Recoveries ranged from 31% to 83%. Low LODs were achieved, between 2 and 10ng/L, allowing a reliable identification of all analytes at trace levels, using only 50mL as sample volume. All studied parameters complied with the defined criteria and the method was successfully applied to gather preliminary results of the determination of antipsychotics on hospital effluents and on influent and effluent of WWTPs, opening perspectives for the study of their fate in the aquatic environment.

When one's sense of agency goes wrong: Absent modulation of time perception by voluntary actions and reduction of perceived length of intervals in passivity symptoms in schizophrenia

Passivity symptoms in schizophrenia are characterised by an absence of agency for actions, thoughts and other somatic experiences. Time perception and intentional binding have both been linked to agency and schizophrenia but have not been examined in passivity symptoms. Time perception and intentional binding were assessed in people with schizophrenia (n=15 with, n=24 without passivity symptoms) and 43 healthy controls using an interval estimation procedure (200, 400 and 600ms intervals) with active, passive and observed movements. People with passivity symptoms did not display action-modulation of time perception, while those without passivity symptoms estimated intervals to be the same after active and observed movements. Additionally, both clinical samples reported intervals to be shorter with increasing interval length. We propose that impaired predictive processes may produce an overreliance on external cues and, together with shorter perceived intervals, lead to the subjective loss of agency.

The effect of second-generation antipsychotic drugs on sleep parameters in patients with unipolar or bipolar disorder

Sleep disturbances predominantly take the form of insomnia in patients with unipolar disorder, while patients with bipolar disorder show a decreased need for sleep. Sleep impairment in these patients is a risk factor for the development of a major depressive episode and suicidal behavior. Administration of second-generation antipsychotics (SGAs) olanzapine, quetiapine, and ziprasidone as augmentation therapy or monotherapy to unipolar and bipolar disorder patients, respectively, has been shown to improve sleep continuity and sleep architecture. Thus, their use by these patients could ameliorate their sleep disorder.

Update on schizophrenia and bipolar disorder: focus on cariprazine

Schizophrenia and bipolar disorder are severe psychiatric disorders that are frequently associated with persistent symptoms and significant dysfunction. While there are a multitude of psychopharmacologic agents are available for treatment of these illnesses, suboptimal response and significant adverse consequences limit their utility. Cariprazine is a new, novel antipsychotic medication with dopamine D2 and D3 partial agonist effects. Its safety and efficacy have been investigated in acute psychosis of schizophrenia, bipolar mania, bipolar depression, and unipolar depression. Efficacy has been demonstrated in schizophrenia and mania. It is unclear if cariprazine is effective in depression associated with unipolar or bipolar illness. Adverse consequences include extrapyramidal symptoms including akathisia, and various gastrointestinal symptoms. The US Food and Drug Administration (FDA) has recently approved cariprazine. This review will provide clinicians with basic information regarding the research program of cariprazine.

Low frontal serotonin 2A receptor binding is a state marker for schizophrenia?

Here we imaged serotonin 2A receptor (5-HT2AR) binding in a very rare population of monozygotic twins discordant for schizophrenia to provide insight into trait and state components in brain 5-HT2AR patterns. In four twin pairs not medicated with drugs that target 5-HT2AR, frontal 5-HT2AR binding was consistently lower (33%) in schizophrenic- relative to their healthy co-twins. Our results strongly imply low frontal 5-HT2AR availability as a state feature of schizophrenia. If replicated, ideally in a larger sample also including dizygotic twin pairs and drug-naïve patients, this finding critically advance our understanding of the complex pathophysiology of schizophrenia.

Primer for nutritionists: Managing the side effects of antidepressants

Depression is a chronic disease affecting a significant portion of the U.S.

POPULATION

Due to the popularity of ADs most nutrition professionals working in the outpatient setting will encounter patients taking one of these medications. Nutritionist can assist patients in managing the short and long term side effects of ADs and, taking into account other nutritional issues, improve overall wellbeing of the patient. The objective of this paper is to identify what side effects nutritionists can help manage, provide the information necessary to help nutritionists feel comfortable assisting with that management, and, as a result, play a valuable role in the team that is vested in the health and wellbeing of the patient.

Central- and autonomic nervous system coupling in schizophrenia

The autonomic nervous system (ANS) dysfunction has been well described in schizophrenia (SZ), a severe mental disorder. Nevertheless, the coupling between the ANS and central brain activity has been not addressed until now in SZ. The interactions between the central nervous system (CNS) and ANS need to be considered as a feedback-feed-forward system that supports flexible and adaptive responses to specific demands. For the first time, to the best of our knowledge, this study investigates central-autonomic couplings (CAC) studying heart rate, blood pressure and electroencephalogram in paranoid schizophrenic patients, comparing them with age-gender-matched healthy subjects (CO). The emphasis is to determine how these couplings are composed by the different regulatory aspects of the CNS-ANS. We found that CAC were bidirectional, and that the causal influence of central activity towards systolic blood pressure was more strongly pronounced than such causal influence towards heart rate in paranoid schizophrenic patients when compared with CO. In paranoid schizophrenic patients, the central activity was a much stronger variable, being more random and having fewer rhythmic oscillatory components. This study provides a more in-depth understanding of the interplay of neuronal and autonomic regulatory processes in SZ and most likely greater insights into the complex relationship between psychotic stages and autonomic activity.

Reduction of Pavlovian Bias in Schizophrenia: Enhanced Effects in Clozapine-Administered Patients

The negative symptoms of schizophrenia (SZ) are associated with a pattern of reinforcement learning (RL) deficits likely related to degraded representations of reward values. However, the RL tasks used to date have required active responses to both reward and punishing stimuli. Pavlovian biases have been shown to affect performance on these tasks through invigoration of action to reward and inhibition of action to punishment, and may be partially responsible for the effects found in patients. Forty-five patients with schizophrenia and 30 demographically-matched controls completed a four-stimulus reinforcement learning task that crossed action ("Go" or "NoGo") and the valence of the optimal outcome (reward or punishment-avoidance), such that all combinations of action and outcome valence were tested. Behaviour was modelled using a six-parameter RL model and EEG was simultaneously recorded. Patients demonstrated a reduction in Pavlovian performance bias that was evident in a reduced Go bias across the full group. In a subset of patients administered clozapine, the reduction in Pavlovian bias was enhanced. The reduction in Pavlovian bias in SZ patients was accompanied by feedback processing differences at the time of the P3a component. The reduced Pavlovian bias in patients is suggested to be due to reduced fidelity in the communication between striatal regions and frontal cortex. It may also partially account for previous findings of poorer "Go-learning" in schizophrenia where "Go" responses or Pavlovian consistent responses are required for optimal performance. An attenuated P3a component dynamic in patients is consistent with a view that deficits in operant learning are due to impairments in adaptively using feedback to update representations of stimulus value.

Interaction of NOS1AP with the NOS-I PDZ domain: Implications for schizophrenia-related alterations in dendritic morphology

Schizophrenia involves morphological brain changes, including changes in synaptic plasticity and altered dendritic development. Amongst the most promising candidate molecules for schizophrenia are neuronal nitric oxide (NO) synthase (NOS-I, also known as nNOS) and its adapter protein NOS1AP (previously named CAPON). However, the precise molecular mechanisms by which NOS-I and NOS1AP affect disease pathology remain to be resolved. Interestingly, overexpression of NOS1AP affects dendritic morphology, possibly through increased association with the NOS-I PDZ domain. To investigate the effect of NOS1AP on dendritic morphology we overexpressed different NOS1AP isoforms, NOS1AP deletion mutants and the aminoterminal 133 amino acids of NOS-I (NOS-IN133) containing an extended PDZ domain. We examined the interaction of the overexpressed constructs with endogenous NOS-I by co-immunoprecipitation and the consequences of increased NOS-I/NOS1AP PDZ interaction in primary cultures of hippocampal and cortical neurons from C57BL/6J mice. Neurons overexpressing NOS1AP isoforms or deletion mutants showed highly altered spine morphology and excessive growth of filopodia-like protrusions. Sholl analysis of immunostained primary cultured neurons revealed that dendritic branching was mildly affected by NOS1AP overexpression. Our results hint towards an involvement of NOS-I/NOS1AP interaction in the regulation of dendritic spine plasticity. As altered dendritic spine development and filopodial outgrowth are important neuropathological features of schizophrenia, our findings may provide insight into part of the molecular mechanisms involved in brain morphology alterations observed in schizophrenia. As the NOS-I/NOS1AP interface can be targeted by small molecules, our findings ultimately might help to develop novel treatment strategies for schizophrenia patients.

Psychopathology, psychopharmacological properties, decision-making capacity to consent to clinical research and the willingness to participate among long-term hospitalized patients with schizophrenia

Many studies discuss factors related to the decision-making capacity to consent to clinical research (DMC) of patients with schizophrenia. However, these studies rarely approached willingness to participate and the association between psychopharmacological properties (e.g., antipsychotic-induced side effects) and DMC. This study aimed to explore factors related to DMC and willingness to participate in patients with schizophrenia. All 139 patients with schizophrenia were assessed with the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) and other measures. A linear regression model was used to find the predictors of MacCAT-CR scores. A logistic regression model was used for exploring the predictors of willingness to participate. Patients with more severe negative symptoms performed poorly in DMC outcomes. In addition, females, those with fewer years of education and reduced cognitive function are more likely to experience difficulties in decision-making. Forty-three subjects (30.4%) chose to participate. Patients with higher level of positive symptoms, longer length of stay, higher burden of anticholinergics and users of atypical antipsychotics were more likely to participate in a clinical study which aimed to "enhance cognition". These finding suggest that research investigators should consider many variables for patients who require more intensive screening for impaired DMC.

On the Complexity of Brain Disorders: A Symptom-Based Approach

Mounting evidence shows that brain disorders involve multiple and different neural dysfunctions, including regional brain damage, change to cell structure, chemical imbalance, and/or connectivity loss among different brain regions. Understanding the complexity of brain disorders can help us map these neural dysfunctions to different symptom clusters as well as understand subcategories of different brain disorders. Here, we discuss data on the mapping of symptom clusters to different neural dysfunctions using examples from brain disorders such as major depressive disorder (MDD), Parkinson’s disease (PD), schizophrenia, posttraumatic stress disorder (PTSD) and Alzheimer’s disease (AD). In addition, we discuss data on the similarities of symptoms in different disorders. Importantly, computational modeling work may be able to shed light on plausible links between various symptoms and neural damage in brain disorders.

Dopaminergic receptor-ligand binding assays based on molecularly imprinted polymers on quartz crystal microbalance sensors

Molecularly imprinted polymers (MIPs) have been successfully applied as selective materials for assessing the binding activity of agonist and antagonist of dopamine D1 receptor (D1R) by using quartz crystal microbalance (QCM). In this study, D1R derived from rat hypothalamus was used as a template and thus self-organized on stamps. Those were pressed into an oligomer film consisting of acrylic acid: N-vinylpyrrolidone: N,N'-(1,2-dihydroxyethylene) bis-acrylamide in a ratio of 2:3:12 spin coated onto a dual electrode QCM. Such we obtained one D1R-MIP-QCM electrode, whereas the other electrode carried the non-imprinted control polymer (NIP) that had remained untreated. Successful imprinting of D1R was confirmed by AFM. The polymer can re-incorporate D1R leading to frequency responses of 100-1200Hz in a concentration range of 5.9-47.2µM. In a further step such frequency changes proved inherently useful for examining the binding properties of test ligands to D1R. The resulting mass-sensitive measurements revealed Kd of dopamine∙HCl, haloperidol, and (+)-SCH23390 at 0.874, 25.6, and 0.004nM, respectively. These results correlate well with the values determined in radio ligand binding assays. Our experiments revealed that D1R-MIP sensors are useful for estimating the strength of ligand binding to the active single site. Therefore, we have developed a biomimetic surface imprinting strategy for QCM studies of D1R-ligand binding and presented a new method to ligand binding assay for D1R.

Overexpression of Isoforms of Nitric Oxide Synthase 1 Adaptor Protein, Encoded by a Risk Gene for Schizophrenia, Alters Actin Dynamics and Synaptic Function

Proper communication between neurons depends upon appropriate patterning of dendrites and correct distribution and structure of spines. Schizophrenia is a neuropsychiatric disorder characterized by alterations in dendrite branching and spine density. Nitric oxide synthase 1 adaptor protein (NOS1AP), a risk gene for schizophrenia, encodes proteins that are upregulated in the dorsolateral prefrontal cortex (DLPFC) of individuals with schizophrenia. To elucidate the effects of NOS1AP overexpression observed in individuals with schizophrenia, we investigated changes in actin dynamics and spine development when a long (NOS1AP-L) or short (NOS1AP-S) isoform of NOS1AP is overexpressed. Increased NOS1AP-L protein promotes the formation of immature spines when overexpressed in rat cortical neurons from day in vitro (DIV) 14 to DIV 17 and reduces the amplitude of miniature excitatory postsynaptic currents (mEPSCs). In contrast, increased NOS1AP-S protein increases the rate of actin polymerization and the number of immature and mature spines, which may be attributed to a decrease in total Rac1 expression and a reduction in the levels of active cofilin. The increase in the number of mature spines by overexpression of NOS1AP-S is accompanied by an increase in the frequency of mEPSCs. Our findings show that overexpression of NOS1AP-L or NOS1AP-S alters the actin cytoskeleton and synaptic function. However, the mechanisms by which these isoforms induce these changes are distinct. These results are important for understanding how increased expression of NOS1AP isoforms can influence spine development and synaptic function.

Regional Abnormality of Grey Matter in Schizophrenia: Effect from the Illness or Treatment?

Both schizophrenia and antipsychotic treatment are known to modulate brain morphology. However, it is difficult to establish whether observed structural brain abnormalities are due to disease or the effects of treatment. The aim of this study was to investigate the effects of illness and antipsychotic treatment on brain structures in antipsychotic-naïve first-episode schizophrenia based on a longitudinal short-term design. Twenty antipsychotic-naïve subjects with first-episode schizophrenia and twenty-four age- and sex-matched healthy controls underwent 3T MRI scans. Voxel-based morphometry (VBM) was used to examine the brain structural abnormality in patients compared to healthy controls. Nine patients were included in the follow-up examination after 8 weeks of treatment. Tensor-based morphometry (TBM) was used to identify longitudinal brain structural changes. We observed significantly reduced grey matter volume in the right superior temporal gyrus in antipsychotic-naïve patients with schizophrenia compared with healthy controls. After 8 weeks of treatment, patients showed significantly increased grey matter volume primarily in the bilateral prefrontal cortex, insula, right thalamus, left superior occipital cortex and the bilateral cerebellum. In addition, a greater enlargement of the prefrontal cortex is associated with the improvement in negative symptoms, and a more enlarged thalamus is associated with greater improvement in positive symptoms. Our results suggest the following: (1) the abnormality in the right superior temporal gyrus is present in the early stages of schizophrenia, possibly representing the core region related to schizophrenia; and (2) atypical antipsychotics could modulate brain morphology involving the thalamus, cortical grey matter and cerebellum. In addition, examination of the prefrontal cortex and thalamus might facilitate an efficient response to atypical antipsychotics in terms of symptom improvement.

Quetiapine monotherapy in acute treatment of generalized anxiety disorder: a systematic review and meta-analysis of randomized controlled trials

Background

Some studies have indicated the efficacy of quetiapine in the treatment of generalized anxiety disorder (GAD).

Objective

The purpose of this study was to systematically review the efficacy, acceptability, and tolerability of quetiapine in adult patients with GAD.

Methods

The SCOPUS, MEDLINE, CINAHL, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov databases were searched in April 2015. All randomized controlled trials (RCTs) of GAD were considered to be included in this meta-analysis. All RCTs of quetiapine in GAD patients providing endpoint outcomes relevant to severity of anxiety, response rate, remission rate, overall discontinuation rate, or discontinuation rate due to adverse events were included. The version reports from suitable clinical studies were explored, and the important data were extracted. Measurement for efficacy outcomes consisted of the mean-changed scores of the rating scales for anxiety, and response rate.

Results

A total of 2,248 randomized participants in three RCTs were included. The pooled mean-changed score of the quetiapine-treated group was greater than that of the placebo-treated group and comparable to selective serotonin reuptake inhibitors (SSRIs). Unfortunately, the response and the remission rates in only 50 and 150 mg/day of quetiapine-XR (extended-release) were better than those of the placebo. Their response and remission rates were comparable to SSRIs. The rates of pooled overall discontinuation and discontinuation due to adverse events of quetiapine-XR were greater than placebo. Only the overall discontinuation rate of quetiapine-XR at 50 and 150 mg/day and the discontinuation rate due to adverse events of quetiapine-XR at 50 mg/day were comparable to SSRIs.

Conclusion

Based on this meta-analysis, quetiapine-XR is efficacious in the treatment of GAD in adult patients. Despite its low acceptability and tolerability, the use of 50–150 mg/day quetiapine-XR for adult GAD patients may be considered as an alternative treatment. Further well-defined studies should be conducted to warrant these outcomes.

Blood lactate levels as a biomarker of antipsychotic side effects in patients with schizophrenia

BACKGROUND

Antipsychotic drugs (APs) are widely prescribed in psychiatry primarily for the treatment of psychosis in schizophrenia and bipolar disorders. An issue related to poor prognosis in patients with chronic illness relates to the accumulation of lactate levels in blood, leading to patients that become critically ill. It is suggested that haloperidol and olanzapine, as common therapy for schizophrenia, are associated with increased levels of blood lactate, which may contribute towards the extra-pyramidal side effects.

AIMS AND METHOD

In this study, 88 patients attending the psychiatry outpatient clinic of Mansoura University Hospital, under treatment with typical APs (chlorpromazine or haloperidol) or the atypical APs (risperidone, olanzapine or quetiapine) were followed over a three-month period. Blood lactate levels were assessed at diagnosis, ten days and 90 days after the start of AP treatment. Extra-pyramidal symptoms (EPSs) were studied in participants during the course of this study.

RESULTS

Chlorpromazine and haloperidol caused significant increases in lactate levels within the first ten days of therapy, while after 90 days, all APs showed significant increases in arterial blood lactate levels in comparison with the first baseline measurement (for all APs, p-values <0.0001). Dystonia was reported by patients on chlorpromazine, haloperidol and risperidone therapies, while Parkinsonian-like manifestations were reported with all APs tested except for quetiapine. Both dystonia and Parkinsonian-like manifestations were also observed alongside the significant increases in arterial blood lactate levels in comparison to patients on therapy not displaying EPSs.

CONCLUSION

These findings suggest elevated blood lactate levels may serve as early biomarkers for occurrence of extra-pyramidal symptoms in patients on chronic APs treatment.

Rethinking psychopharmacotherapy: The role of treatment context and brain plasticity in antidepressant and antipsychotic interventions

Emerging evidence indicates that treatment context profoundly affects psychopharmacological interventions. We review the evidence for the interaction between drug application and the context in which the drug is given both in human and animal research. We found evidence for this interaction in the placebo response in clinical trials, in our evolving knowledge of pharmacological and environmental effects on neural plasticity, and in animal studies analyzing environmental influences on psychotropic drug effects. Experimental placebo research has revealed neurobiological trajectories of mechanisms such as patients' treatment expectations and prior treatment experiences. Animal research confirmed that "enriched environments" support positive drug effects, while unfavorable environments (low sensory stimulation, low rates of social contacts) can even reverse the intended treatment outcome. Finally we provide recommendations for context conditions under which psychotropic drugs should be applied. Drug action should be steered by positive expectations, physical activity, and helpful social and physical environmental stimulation. Future drug trials should focus on fully controlling and optimizing such drug×environment interactions to improve trial sensitivity and treatment outcome.

Effect of cariprazine across the symptoms of mania in bipolar I disorder: Analyses of pooled data from phase II/III trials

Bipolar I disorder is a chronic disorder characterized by episodic recurrences of mania, depression, and mixed affective states interspersed with periods of full or partial remission; subsyndromal residual symptoms between episodes are common and disabling. Cariprazine, an atypical antipsychotic, is a potent dopamine D3 and D2 receptor partial agonist with preferential binding to D3 receptors. Post-hoc analyses of pooled data from 3 positive trials were conducted to evaluate the effect of cariprazine 3-12 mg/d on the symptoms of mania in inpatients (18-65 years) with bipolar I disorder and a current manic episode. Analyses were based on the pooled intent-to-treat (ITT) population (placebo=429; cariprazine=608). Mean change from baseline to the end of treatment on individual Young Mania Rating Scale (YMRS) items was analysed using a mixed-effects model for repeated measures (MMRM); categorical symptom severity shifts were analysed using logistic regression. Statistically significant improvement in mean change was seen for cariprazine versus placebo on all 11 YMRS items (p<0.0001); significantly more cariprazine- versus placebo-treated patients had mild/no symptoms at the end of treatment on 11 YMRS items (p<0.0001) and concurrently on the 4 YMRS core symptoms (irritability, speech, content, and disruptive-aggressive behaviour) (p<0.0001). Significantly more cariprazine- versus placebo-treated patients shifted from a Moderate/Worse or Marked/Worse Symptoms categories to Mild/No Symptoms on all 11 (p<0.0001) and 9 of 11 YMRS items (p<0.05), respectively. Results suggest that cariprazine treatment improved mania across YMRS symptoms; a significant percentage of cariprazine- versus placebo-treated patients had mild/no symptoms at the end of treatment.

No progression of the alterations in the cortical thickness of individuals with schizophrenia-spectrum disorder: a three-year longitudinal magnetic resonance imaging study of first-episode patients

BACKGROUND

Cortical thickness measurement offers an index of brain development processes. In healthy individuals, cortical thickness is reduced with increasing age and is related to cognitive decline. Cortical thinning has been reported in schizophrenia. Whether cortical thickness changes differently over time in patients and its impact on outcome remain unanswered.

METHOD

Data were examined from 109 patients and 76 healthy controls drawn from the Santander Longitudinal Study of first-episode schizophrenia for whom adequate structural magnetic resonance imaging (MRI) data were available (n = 555 scans). Clinical and cognitive assessments and MRIs were acquired at three regular time points during a 3-year follow-up period. We investigated likely progressive cortical thickness changes in schizophrenia during the first 3 years after initiating antipsychotic treatment. The effects of cortical thickness changes on cognitive and clinical variables were also examined along with the impact of potential confounding factors.

RESULTS

There were significant diagnoses × scan time interaction main effects for total cortical thickness (F 1,309.1 = 4.60, p = 0.033) and frontal cortical thickness (F 1,310.6 = 5.30, p = 0.022), reflecting a lesser thinning over time in patients. Clinical and cognitive outcome was not associated with progressive cortical changes during the early years of the illness.

CONCLUSIONS

Cortical thickness abnormalities do not unswervingly progress, at least throughout the first years of the illness. Previous studies have suggested that modifiable factors may partly account for cortical thickness abnormalities. Therefore, the importance of implementing practical actions that may modify those factors and improve them over the course of the illness should be highlighted.

Clozapine improves the orienting of attention in schizophrenia

Attentional deficits are prominent in the cognitive profile of patients with schizophrenia. However, it remains unclear whether treatment with clozapine, an atypical antipsychotic and first-line intervention used to reduce positive and negative symptoms of psychosis, improves the attentional functions. We used the revised attention network test to measure alerting, orienting, and executive control of attention both pre- and post-treatment with clozapine in patients with schizophrenia (n=32) and compared performance to healthy controls (n=32). Results revealed that there were deficits in all three attentional functions pre-treatment, and while clozapine improved the orienting function in patients with schizophrenia, there was no evidence for improvement in the alerting and executive control of attention. The enhancement of the orienting function by clozapine may increase the ability of patients with schizophrenia to orient towards objects and thoughts of interest.

DNA methylation in psychosis: insights into etiology and treatment

Evidence for involvement of DNA methylation in psychosis forms the focus of this perspective. Of interest are results from two independent sets of experiments including rats treated with antipsychotic drugs and monozygotic twins discordant for schizophrenia. The results show that DNA methylation is increased in rats treated with antipsychotic drugs, reflecting the global effect of the drugs. Some of these changes are also seen in affected schizophrenic twins that were treated with antipsychotics. The genes and pathways identified in the unrelated experiments are relevant to neurodevelopment and psychiatric disorders. The common cause is hypothesized to be aberrations resulting from medication use. However, this needs to be established by future studies that address the origin of methylation changes in psychosis.

Effects of weight loss diet therapy on anthropometric measurements and biochemical variables in schizophrenic patients

BACKGROUND

Prevalence of obesity in schizophrenic patients is two to three times higher than in the general population and unhealthy dietary patterns, a sedentary lifestyle and antipsychotic medication use may contribute to the higher levels of obesity among schizophrenic patients.

AIMS

We evaluated the effects of diet therapy on weight loss, anthropometric and biochemical variables in overweight or obese (body mass index, BMI ≥ 27 kg/m(2)) female schizophrenic patients who use antipsychotic medications and in healthy volunteers.

METHODS

Primary demographic variables were collected via questionnaire; blood samples and anthropometric measurements were obtained. Personalized diet recipes were prepared and nutritional education was shared. We logged the physical activity of the patients and maintained food consumption records at 3-day intervals. Participants were weighed every week; anthropometric measurements and blood samples were collected at the end of the first and second months.

RESULTS

At the end of the study, reductions in body weight and other anthropometric measurements were statistically significant (P < 0.05). Reductions in body weight and BMI values for patient group were - 4.05 ± 1.73 kg and - 1.62 ± 0.73 kg/m(2) and for the control group were - 6.79 ± 1.80 kg and - 2.55 ± 0.64 kg/m(2), respectively. When compared with the patient group, reductions in the anthropometric variables of the control group were statistically significant (P < 0.05). Fasting glucose, blood lipids, albumin and leptin levels were decreased; insulin and homeostatic model assessment-measured insulin resistance (HOMA-IR) levels were increased insignificantly. Increases in the blood ghrelin levels for both groups were statistically significant (P < 0.05).

CONCLUSIONS

Improvements to the diets of schizophrenic patient led to improvements in anthropometric measurements and biochemical variables and reduced the health risks caused by antipsychotic medications. Furthermore, we hypothesize that antipsychotic medications do not have any direct effect on leptin and ghrelin metabolism, and that changes in hormone metabolism may be attributable to changes in body weight.

Psychopharmacology of atypical antipsychotic drugs: From the receptor binding profile to neuroprotection and neurogenesis

The original definition of atypical antipsychotic drugs (APD) was drugs that are effective against positive symptoms in schizophrenia with no or little extrapyramidal symptoms (EPS). However, atypical APD have been reported to be more effective for cognitive dysfunction and negative symptoms in schizophrenia than typical APD, which expands the definition of 'atypicality'. This article provides a critical review of the pharmacology of atypical APD, especially from the viewpoint of receptor binding profiles and neurotransmitter regulations as well as neuroprotection and neurogenesis. A variety of serotonin (5-HT) receptors, such as 5-HT2A / 2C , 5-HT1A , 5-HT6 and 5-HT7 receptors, may contribute to the mechanisms of action of 'atypicality'. The dopaminergic modulations, including a low affinity for dopamine D2 receptors and a partial D2 receptor agonistic action, and glutamatergic regulations may also be involved in the pharmacological backgrounds of 'atypicality'. Atypical APD, but not typical APD, may facilitate cortical neuroprotection and hippocampal neurogenesis, which might be a part of the action mechanisms of atypical APD. The facilitation of cortical neuroprotection and hippocampal neurogenesis induced by atypical APD might be mediated by an increase in the Ser9 phosphorylation of glycogen synthase kinase-3β (GSK-3β). The stimulation of 5-HT1A receptors and/or the blockade of 5-HT2 receptors, which is characteristic of atypical APD, might increase Ser9 phosphorylation of GSK-3β. Moreover, atypical APD increase brain-derived neurotrophic factor (BDNF) levels. BDNF increases Ser9 phosphorylation of GSK-3β and has neuroprotective and neurogenic effects, as in the case of atypical APD. These findings suggest that GSK-3β might play a role in the action mechanisms of atypical APD, in both the 5-HT-dependent and BDNF-dependent mechanisms.

Therapeutic drug levels of second generation antipsychotics in youth: a systematic review

OBJECTIVE

In children and adolescents, the prevalence rate of mental illness is claimed to be as high as 10-20%. Effective pharmacological treatments are available for use in children, adolescents, and adults; however, most of what is known about the effects of these treatments has been confirmed in clinical studies involving adults only. Second generation antipsychotic drugs (SGAs) are the most common class of antipsychotic medication used in pediatric populations, and these drugs are increasingly being used for disorders other than psychosis. Many SGAs are routinely used in pediatric care, and the vast majority of use in this population is off label. Children, adolescents, and adults differ in age, weight, height, and metabolism, which may lead to pharmacokinetic differences in how drugs ultimately affect target tissues. The aim of this review is to summarize and evaluate the literature that investigated blood plasma levels of SGAs in youth.

METHODS

Plasma levels were assessed in relation to their administered dose, indication, and therapeutic range (if known). Studies were limited to those evaluating oral administration only. A systematic electronic database search for peer-reviewed articles published between 2000 and 2013 was conducted. Twenty-one articles were included in the review. Additional articles for discussion were also included throughout the article.

RESULTS

The only SGA that may require routine therapeutic drug monitoring (TDM) in youth given the current body of research is clozapine. Highly variable results were seen in studies of aripiprazole, olanzapine, and risperidone, indicating that more research is needed on plasma levels with these drugs. Quetiapine maintained a similar profile to that found in adults, with no dosage adjustments or indications of TDM.

CONCLUSION

TDM may be indicated in any circumstance in which cytochrome P450 inhibitors or inducers are coprescribed. Further research is required for establishing a sounder safety profile for SGA use in the pediatric population.

Antibodies to surface dopamine-2 receptor and N-methyl-D-aspartate receptor in the first episode of acute psychosis in children

BACKGROUND

The dopamine and glutamate hypotheses are well known in psychosis. Recently, the detection of autoantibodies against proteins expressed on the surface of cells in the central nervous system has raised the possibility that specific immune-mediated mechanisms may define a biological subgroup within psychosis, although no cohort of a first episode of psychosis in children has been investigated.

METHODS

Serum taken during the acute presentation of 43 children with first episode of psychosis and serum from 43 pediatric control subjects was assessed for the presence of immunoglobulin (Ig)G, IgM, or IgA antibodies to dopamine-2 receptor (D2R) and NR1 subunit of the N-methyl-D-aspartate receptor using a flow cytometry live cell-based assay and immunolabeling of murine primary neurons.

RESULTS

Using a cutoff of three SD above the control mean, serum antibodies to D2R or NR1 were detected in 8 of 43 psychotic patients but not detected in any of 43 control subjects (p < .001). Positive immunoglobulin binding to D2R was found in 3 of 43 psychosis patients (3 IgG, 1 IgM, 0 IgA) and to N-methyl-D-aspartate receptor in 6 of 43 patients (5 IgG, 1 IgM, 1 IgA). Specificity of antibody was confirmed by immunoaffinity purification and immunoabsorption. Significant differences in antibody binding to live, fixed, and fixed and permeabilized neurons were observed, confirming that only live cells can define surface epitope immunolabeling.

CONCLUSIONS

This is the first report of serum antibodies to surface D2R and NR1 in pediatric patients with isolated psychosis, which supports the hypothesis that a subgroup of patients may be immune-mediated.

Second-generation antipsychotics and neuroleptic malignant syndrome: systematic review and case report analysis

BACKGROUND

Neuroleptic malignant syndrome (NMS) is a rare, severe, idiosyncratic adverse reaction to antipsychotics. Second-generation antipsychotics (SGAs) were originally assumed to be free from the risk of causing NMS, however several cases of NMS induced by SGAs (SGA-NMS) have been reported.

OBJECTIVES

The aim of this study was to systematically review available studies and case reports on SGA-NMS and compare the presentation of NMS induced by different SGAs.

DATA SOURCES

Citations were retrieved from PubMed up to November 2013, and from reference lists of relevant citations.

STUDY ELIGIBILITY CRITERIA

Eligibility criteria included (a) primary studies reporting data on NMS, with at least 50 % of the sample receiving SGAs; or (b) case reports and case reviews reporting on NMS induced by SGA monotherapy, excluding those due to antipsychotic withdrawal.

STUDY APPRAISAL AND SYNTHESIS METHODS

A standardized method for data extraction and coding was developed for the analysis of eligible case reports.

RESULTS

Six primary studies and 186 individual cases of NMS induced by SGAs were included. Primary studies suggest that SGA-NMS is characterized by lower incidence, lower clinical severity, and less frequent lethal outcome than NMS induced by first-generation antipsychotics. Systematic analysis of case reports suggests that even the most recently marketed antipsychotics are not free from the risk of inducing NMS. Furthermore, clozapine-, aripiprazole- and amisulpride-induced NMS can present with atypical features more frequently than other SGA-NMS, i.e. displaying less intense extrapyramidal symptoms or high fever.

LIMITATIONS

Case reports report non-systematic data, therefore analyses may be subject to bias.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Clinicians should be aware that NMS is virtually associated with all antipsychotics, including those most recently marketed. Although apparently less severe than NMS induced by older antipsychotics, SGA-NMS still represent a relevant clinical issue.

Temporal and spatial transcriptional fingerprints by antipsychotic or propsychotic drugs in mouse brain

Various types of antipsychotics have been developed for the treatment of schizophrenia since the accidental discovery of the antipsychotic activity of chlorpromazine. Although all clinically effective antipsychotic agents have common properties to interact with the dopamine D2 receptor (D2R) activation, their precise mechanisms of action remain elusive. Antipsychotics are well known to induce transcriptional changes of immediate early genes (IEGs), raising the possibility that gene expressions play an essential role to improve psychiatric symptoms. Here, we report that while different classes of antipsychotics have complex pharmacological profiles against D2R, they share common transcriptome fingerprint (TFP) profile of IEGs in the murine brain in vivo by quantitative real-time PCR (qPCR). Our data showed that various types of antipsychotics with a profound interaction of D2R including haloperidol (antagonist), olanzapine (antagonist), and aripiprazole (partial agonist) all share common spatial TFPs closely homologous to those of D2R antagonist sulpiride, and elicited greater transcriptional responses in the striatum than in the nucleus accumbens. Meanwhile, D2R agonist quinpirole and propsychotic NMDA antagonists such as MK-801 and phencyclidine (PCP) exhibited the contrasting TFP profiles. Clozapine and propsychotic drug methamphetamine (MAP) displayed peculiar TFPs that reflect their unique pharmacological property. Our results suggest that transcriptional responses are conserved across various types of antipsychotics clinically effective in positive symptoms of schizophrenia and also show that temporal and spatial TFPs may reflect the pharmacological features of the drugs. Thus, we propose that a TFP approach is beneficial to evaluate novel drug candidates for antipsychotic development.

Effects of lithium on cortical thickness and hippocampal subfield volumes in psychotic bipolar disorder

Relative to healthy controls, lithium free bipolar patients exhibit significant gray matter abnormalities. Lithium, the long-time reference standard medication treatment for bipolar disorder, has been proposed to be neuro-protective against these abnormalities. However, its effects on cortical thickness and hippocampal subfield (HSF) volumes remain unstudied and unclear, respectively, in bipolar disorder. This study included 342 healthy controls (HC), 51 lithium free PBD patients (NoLi), and 51 PBD patients taking lithium (Li). Regional gray matter thickness and HSF volume values were extracted from 3T MRI images. After matching NoLi and Li samples, regions where HC differed from either Li or NoLi were identified. In regions of significant or trending HC-NoLi difference, Li-NoLi comparisons were made. No significant HC-Li thickness or HSF volume differences were found. Significantly thinner occipital cortices were observed in NoLi compared to HC. In these regions, Li consistently exhibited non-significant trends for greater cortical thickness relative to NoLi. Significantly less volume was observed in NoLi compared to both HC and Li in right HSFs. Our results suggest that PBD in patients not treated with Li is associated with thinner occipital cortices and reduced HSF volumes compared with HC. Patients treated with Li exhibited significantly larger HSF volumes than NoLi, and those treated with Li were no different from HC in cortical thickness or hippocampal volumes. This evidence directly supports the hypothesis that Li may counteract the locally thinner and smaller gray matter structure found in PBD.

Chronic betahistine co-treatment reverses olanzapine's effects on dopamine D₂ but not 5-HT2A/2C bindings in rat brains

Olanzapine is widely prescribed for treating schizophrenia and other mental disorders, although it leads to severe body weight gain/obesity. Chronic co-treatment with betahistine has been found to significantly decrease olanzapine-induced weight gain; however, it is not clear whether this co-treatment affects the therapeutic effects of olanzapine. This study investigated the effects of chronic treatment of olanzapine and/or betahistine on the binding density of the serotonergic 5-HT2A (5-HT2AR) and 5-HT2C (5-HT2CR) receptors, 5-HT transporter (5-HTT), and dopaminergic D₂ receptors (D₂R) in the brain regions involved in antipsychotic efficacy, including the prefrontal cortex (PFC), cingulate cortex (Cg), nucleus accumbens (NAc), and caudate putamen (CPu). Rats were treated with olanzapine (1 mg/kg, t.i.d.) or vehicle for 3.5 weeks, and then olanzapine treatment was withdrawn for 19 days. From week 6, the two groups were divided into 4 groups (n=6) for 5 weeks' treatment: (1) olanzapine-only (1 mg/kg, t.i.d.), (2) betahistine-only (9.6 mg/kg, t.i.d.), (3) olanzapine and betahistine co-treatment (O+B), and (4) vehicle. Compared to the control, the olanzapine-only treatment significantly decreased the bindings of 5-HT2AR, 5-HT2CR, and 5-HTT in the PFC, Cg, and NAc. Similar changes were observed in the rats receiving the O+B co-treatment. The olanzapine-only treatment significantly increased the D₂R binding in the Cg, NAc, and CPu, while the betahistine-only treatment reduced D₂R binding. The co-treatment of betahistine reversed the D₂R bindings in the NAc and CPu that were increased by olanzapine. Therefore, chronic O+B co-treatment has similar effects on serotonin transmission as the olanzapine-only treatment, but reverses the D₂R that is up-regulated by chronic olanzapine treatment. The co-treatment maintains the therapeutic effects of olanzapine but decreases/prevents the excess weight gain.

Efficacy of lurasidone across five symptom dimensions of schizophrenia: pooled analysis of short-term, placebo-controlled studies

OBJECTIVE

To evaluate the efficacy of lurasidone for schizophrenia using an established five-factor model of the Positive and Negative Syndrome Scale (PANSS).

METHODS

Patient-level data were pooled from five randomized, double-blind, placebo-controlled, 6-week studies of lurasidone (fixed doses, 40-160mg/d) for patients with an acute exacerbation of schizophrenia. Changes in five established PANSS factors were assessed using mixed-model repeated measures analysis.

RESULTS

Compared with placebo (n=496), lurasidone (n=1029, dose groups pooled) significantly improved the PANSS total score at Week 6 (-22.6 vs. -12.8; P<0.001; effect size, 0.45), as well as all factor scores (P<0.001 for each): positive symptoms (-8.4 vs. -6.0; effect size, 0.43), negative symptoms (-5.2 vs. -3.3; effect size, 0.33), disorganized thought (-4.9 vs. -2.8; effect size, 0.42), hostility/excitement (-2.7 vs. -1.6; effect size, 0.31), and depression/anxiety (-3.2 vs. -2.3; effect size, 0.31). Separation from placebo occurred at Week 1 for the positive symptoms, disorganized thought, and hostility/excitement factors and at Week 2 for the other factors.

CONCLUSIONS

In this pooled analysis of short-term studies in patients with acute schizophrenia, lurasidone demonstrated significant improvement for each of the five PANSS factor scores, indicating effectiveness across the spectrum of schizophrenia symptoms.

Effects of dopamine D2/D3 blockade on human sensory and sensorimotor gating in initially antipsychotic-naive, first-episode schizophrenia patients

It has been suggested that psychophysiological measures of sensory and sensorimotor gating, P50 gating and prepulse inhibition of the startle reflex (PPI), underlie core features of schizophrenia and are linked to dopaminergic pathways in the striatum and prefrontal cortex. In the present study, the effects of a potent D2/D3 receptor antagonist, amisulpride, were investigated on PPI and P50 gating in a large sample of antipsychotic-naive, first-episode patients with schizophrenia. A total of 52 initially antipsychotic-naive, first-episode schizophrenia patients were assessed for their P50 gating, PPI, and habituation/sensitization abilities at baseline and after 2 and 6 weeks of treatment with flexible doses of amisulpride. In addition, 47 matched healthy controls were assessed at baseline and after 6 weeks. At baseline, the patients showed significantly reduced PPI, yet normal levels of P50 gating, habituation, and sensitization. Treatment with amisulpride showed no effects on these measures, either at 2 or 6 weeks of follow-up. This is the first study investigating the effects of monotherapy with a relatively selective dopamine D2/D3 receptor antagonist (amisulpride) on sensory and sensorimotor gating deficits in a longitudinal study of a large group of initially antipsychotic-naive, first-episode patients with schizophrenia. Our finding that amisulpride effectively reduced symptom severity in our patients without reducing their PPI deficits indicates that increased activity of dopamine D2 receptors may be involved in symptomatology of patients with schizophrenia, but not in their sensorimotor gating deficits.

Neocortical serotonin2A receptor binding predicts quetiapine associated weight gain in antipsychotic-naive first-episode schizophrenia patients

Antipsychotic-induced weight gain is of major clinical importance since it is associated with severe metabolic complications and increased mortality. The serotonin2A receptor system has been suggested to be implicated in weight gain and obesity. However, no previous in vivo imaging data have related serotonin2A receptor binding to weight gain before and after antipsychotic monotherapy. Fifteen antipsychotic-naive first-episode schizophrenia patients were included and investigated before and after six months of quetiapine treatment. We examined the relationship between serotonin2A receptor binding as measured with positron emission tomography (PET) and [18F]altanserin and change in body mass index (BMI). Quetiapine was chosen because it is characterized by a moderately high affinity for the serotonin2A receptor and a fast dissociation rate from the dopamine D2 receptor. At baseline the mean BMI was 24.2 kg/m2, range 18-36 kg/m2. After six months of quetiapine treatment (mean dose: 383 mg/day) the BMI had, on average, increased by 6.7%, corresponding to an average weight gain of 5.0 kg. We found a significant positive correlation both between neocortical serotonin2A receptor binding prior to treatment and subsequent increase in BMI (rho=0.59, p=0.022). At follow-up, the serotonin2A receptor occupancy was positively correlated with BMI increase (rho=0.54, p=0.038). To our knowledge, these are the first in vivo receptor imaging data in initially antipsychotic-naive first-episode schizophrenia patients to show that the cerebral serotonin2A receptor is associated with antipsychotic-induced weight gain.

Prediction of brain clozapine and norclozapine concentrations in humans from a scaled pharmacokinetic model for rat brain and plasma pharmacokinetics

BACKGROUND

Clozapine is highly effective in treatment-resistant schizophrenia, although, there remains significant variability in the response to this drug. To better understand this variability, the objective of this study was to predict brain extracellular fluid (ECF) concentrations and receptor occupancy of clozapine and norclozapine in human central nervous system by translating plasma and brain ECF pharmacokinetic (PK) relationships in the rat and coupling these with known human disposition of clozapine in the plasma.

METHODS

Unbound concentrations of clozapine and norclozapine were measured in rat brain ECF using quantitative microdialysis after subcutaneous administration of a 10 mg/kg single dose of clozapine or norclozapine. These data were linked with plasma concentrations obtained in the same rats to develop a plasma-brain ECF compartmental model. Parameters describing brain ECF disposition were then allometrically scaled and linked with published human plasma PK to predict human ECF concentrations. Subsequently, prediction of human receptor occupancy at several CNS receptors was based on an effect model that related the predicted ECF concentrations to published concentration-driven receptor occupancy parameters.

RESULTS

A one compartment model with first order absorption and elimination best described clozapine and norclozapine plasma concentrations in rats. A delay in the transfer of clozapine and norclozapine from plasma to the brain ECF compartment was captured using a transit compartment model approach. Human clozapine and norclozapine concentrations in brain ECF were simulated, and from these the median percentage of receptor occupancy of dopamine-2, serotonin-2A, muscarinic-1, alpha-1 adrenergic, alpha-2 adrenergic and histamine-1 for clozapine, and dopamine-2 for norclozapine were consistent with values reported in the literature.

CONCLUSIONS

A PK model that relates clozapine and norclozapine disposition in rat plasma and brain, including blood-brain barrier transport, was developed. Using allometry and published human plasma PK, the model was successfully translated to predict clozapine and norclozapine concentrations and accordant receptor occupancy of both agents in human brain. These predicted exposure and occupancy measures at several receptors that bind clozapine may be employed to extend our understanding of clozapine's complex behavioral effects in humans.

Treatment with the antipsychotic agent, risperidone, reduces disease severity in experimental autoimmune encephalomyelitis

Recent studies have demonstrated that atypical antipsychotic agents, which are known to antagonize dopamine D2 and serotonin 5-HT_2a receptors, have immunomodulatory properties. Given the potential of these drugs to modulate the immune system both peripherally and within the central nervous system, we investigated the ability of the atypical anti-psychotic agent, risperidone, to modify disease in the animal model of multiple sclerosis (MS)⁴, experimental autoimune encephalomyelitis (EAE). We found that chronic oral administration of risperidone dose-dependently reduced the severity of disease and decreased both the size and number of spinal cord lesions. Furthermore, risperidone treatment substantially reduced antigen-specific interleukin (IL)-17a, IL-2, and IL-4 but not interferon (IFN)-γ production by splenocytes at peak disease and using an in vitro model, we show that treatment of macrophages with risperidone alters their ability to bias naïve T cells. Another atypical antipsychotic agent, clozapine, showed a similar ability to modify macrophages in vitro and to reduce disease in the EAE model but this effect was not due to antagonism of the type 1 or type 2 dopamine receptors alone. Finally, we found that while risperidone treatment had little effect on the in vivo activation of splenic macrophages during EAE, it significantly reduced the activation of microglia and macrophages in the central nervous system. Together these studies indicate that atypical antipsychotic agents like risperidone are effective immunomodulatory agents with the potential to treat immune-mediated diseases such as MS.

Treatment of methamphetamine-induced psychosis: a double-blind randomized controlled trial comparing haloperidol and quetiapine

RATIONALE

To our knowledge, only a few double-blind randomized controlled trials with antipsychotic drugs have been conducted to examine the treatment of methamphetamine-induced psychosis (MAP).

OBJECTIVES

The aims of this study are to compare the antipsychotic and adverse events of quetiapine, an atypical antipsychotic drug, to haloperidol, a standard treatment for primary psychotic disorder, in individuals with MAP.

METHODS

Eighty individuals with MAP were randomly assigned into two groups, i.e. treatment with quetiapine (n = 36) and haloperidol (n = 44). Sixty-eight patients (85 %) completed the study protocol, i.e. treatment with quetiapine at least 100 mg per day or haloperidol at least 2 mg per day orally once a day for 4 weeks. The doses were increased every 5 days until no psychotic symptom was observed from the Positive and Negative Syndrome Scale (PANSS). Data were analysed by survival analysis with Cox's proportional regression analysis, general estimating equations and log-rank tests.

RESULTS

Thirty-two (89 %) subjects from the quetiapine group and 37 subjects (84 %) from the haloperidol group met the remission criteria at the end of the study. Baseline PANSS total scores of quetiapine and haloperidol groups were 82.4 ± 16.6 and 90.0 ± 18.4, respectively (mean ± SD; p = 0.06). The change-from-baseline scores were -47.8 for the quetiapine group and -53.2 for the haloperidol group. There were no significant differences between the antipsychotic effects (coefficient value = -2.6, p = 0.32, 95%CI = -7.6, 2.5) and the adverse effects of quetiapine and haloperidol.

CONCLUSIONS

Quetiapine may be used as an antipsychotic treatment for MAP with comparable therapeutic effects and adverse events to treatment with classical antipsychotic drugs.

Clinical effectiveness and resource utilization of paliperidone ER for schizophrenia: Pharmacoepidemiologic International Longitudinal Antipsychotic Registry (PILAR)

OBJECTIVE

To document prescribing patterns in clinical practice and assess long-term outcomes related to initiation of paliperidone ER and other oral antipsychotics among patients with schizophrenia in a naturalistic setting.

RESEARCH DESIGN AND METHODS

An international, non-interventional, naturalistic study of adult patients (≥18 years) with schizophrenia. Patients were assigned to the relevant treatment group (paliperidone ER or 'all other oral antipsychotics') after switching to, or initiating, oral antipsychotic treatment. Retrospective 12 month data collection was followed by 12 month prospective data collection, with 3-monthly assessments. The primary endpoint was time to all-cause discontinuation of new medication. Secondary endpoints included Clinical Global Impression-Severity (CGI-S) score, Clinical Global Impression-Schizophrenia (CGI-SCH) score, Personal and Social Performance (PSP) score, health-related quality of life (HR-QoL) and quality of sleep, evaluation of healthcare resource utilization and patient's treatment satisfaction.

RESULTS

A total of 4051 patients were included in the intent-to-treat (ITT) analysis set. All-cause study discontinuation rates were comparable between the paliperidone ER group (16.8%) and the 'all other oral antipsychotics' group (15.5%). There was no difference in the time to discontinuation of newly initiated antipsychotic treatments between paliperidone ER and 'all other oral antipsychotics' groups. Paliperidone ER was associated with greater improvements from baseline to endpoint in both the PSP scale score (+14.2 vs +13.1, p = 0.041) and the physical component of quality of life (SF-12 Physical scores; +3.9 vs +2.9, p = 0.003) compared to 'all other oral antipsychotics'. Improvements in mean CGI-S score, CGI-SCH score, HR-QoL, quality of sleep and daytime drowsiness, as well as patients' treatment satisfaction were comparable between treatment groups. The incidence of adverse events was comparable between groups.

CONCLUSIONS

This study provides valuable data on the prescribing habits and treatment outcomes associated with use of paliperidone ER in everyday clinical practice, and supports previous findings of the favorable functional improvement and treatment satisfaction associated with paliperidone ER.

CLINICAL TRIAL REGISTRATION

NCT00696813; R076477SCH4015 (Register of German Association of Research-based Pharmaceutical Companies [VFA] http://www.vfa.de/de/arzneimittel-forschung/datenbanken-zu-arzneimitteln/nisdb).

Pleckstrin homology domain containing 6 protein (PLEKHA6) polymorphisms are associated with psychopathology and response to treatment in schizophrenic patients

Pleckstrin homology domain (PH domain) comprises approximately 120 amino acids and is integrated in a wide range of proteins involved in intracellular signaling or as constituents of the cytoskeleton. This domain can bind phosphatidylinositol (3,4,5)-triphosphate and phosphatidylinositol (4,5)-biphosphate and proteins such as the βγ-subunits of heterotrimeric G proteins and protein kinase C. Associations with psychiatric diseases have not been investigated yet. To identify genes involved in response to antipsychotics, mice were treated with haloperidol (1mg/kg, n = 11) or saline (n = 12) for one week. By analyzing microarray data, we observed an increase of pleckstrin homology domain containing 6 (PLEKHA6) gene expression. Furthermore, we genotyped 263 schizophrenic patients, who were treated monotherapeutically with different antipsychotics within randomized-controlled trials. Psychopathology was measured weekly using the PANSS for a minimum of four and a maximum of twelve weeks. Correlations between PANSS subscale scores at baseline and PANSS improvement scores after four weeks of treatment and genotypes were calculated by using a linear model for all investigated SNPs. We found associations between four PLEKHA6 polymorphisms (rs17333933 (T/G), rs3126209 (C/T), rs4951338 (A/G) and rs100900571 (T/C)) and different PANSS subscales at baseline. Furthermore two different polymorphisms (rs7513240 (T/C), rs4951353 (A/G)) were found to be associated with therapy response in terms of a significant correlation with different PANSS improvement subscores after four weeks of antipsychotic treatment. Our observation of an association between genetic polymorphisms of a protein of the PH domain and psychopathology data in schizophrenic patients might be indicative for an involvement of PLEKHA6 in the pathophysiology of schizophrenia and the therapy response towards antipsychotics.

Dopamine D2 receptor occupancy as a predictor of catalepsy in rats: a pharmacokinetic-pharmacodynamic modeling approach

OBJECTIVES

Dopamine D2 receptor occupancy (D2RO) is the major determinant of efficacy and safety in schizophrenia drug therapy. Excessive D2RO (>80%) is known to cause catalepsy (CAT) in rats and extrapyramidal side effects (EPS) in human. The objective of this study was to use pharmacokinetic and pharmacodynamic modeling tools to relate CAT with D2RO in rats and to compare that with the relationship between D2RO and EPS in humans.

METHODS

Severity of CAT was assessed in rats at hourly intervals over a period of 8 h after antipsychotic drug treatment. An indirect response model with and without Markov elements was used to explain the relationship of D2RO and CAT.

RESULTS

Both models explained the CAT data well for olanzapine, paliperidone and risperidone. However, only the model with the Markov elements predicted the CAT severity well for clozapine and haloperidol. The relationship between CAT scores in rat and EPS scores in humans was implemented in a quantitative manner. Risk of EPS not exceeding 10% over placebo correlates with less than 86% D2RO and less than 30% probability of CAT events in rats.

CONCLUSION

A quantitative relationship between rat CAT and human EPS was elucidated and may be used in drug discovery to predict the risk of EPS in humans from D2RO and CAT scores measured in rats.

Psychopharmacology of the negative symptoms: current status and prospects for progress

The past decade has witnessed a resurgence of interest in the development of novel pharmacological agents to treat the negative symptoms of schizophrenia. This review provides an overview of pharmacological approaches that have been evaluated as potential treatments and describes the emergence of several promising new approaches. First, we briefly describe recent methodological developments, including consensus-based clinical trial guidelines for patient selection criteria, symptom assessment, and trial duration. Next, we overview mono- and adjunctive-therapies that have been evaluated, including first- and second-generation antipsychotics, antidepressants, psychostimulants, molecules targeting cholinergic and glutamatergic systems, and hormones. We highlight the most promising pharmacological agents on the horizon, including glycine transporter-1 inhibitors, α7-nicotinic receptor positive allosteric modulators, and oxytocin, as well as non-pharmacological electromagnetic stimulation approaches. Further investigations, using optimal clinical trial design, hold considerable promise for discovering effective treatments for these functionally disabling symptoms in the near future.

Dosing and switching of paliperidone ER in patients with schizophrenia: recommendations for clinical practice

Many patients with schizophrenia receive long-term treatment with antipsychotic medication. Switching of antipsychotic medication due to lack of efficacy, tolerability issues, and partial/non-adherence is common. Despite this, consensus strategies for switching between antipsychotics are lacking. This manuscript provides practical recommendations for switching antipsychotic medication to ensure optimal management of patients with schizophrenia, with a particular focus on paliperidone extended release (ER). The authors drew on their clinical experience supported by detailed discussion of literature describing antipsychotic switching techniques and strategies and findings from paliperidone ER clinical trials. Antipsychotic switching strategies should be individualized and take into consideration the pharmacokinetic (PK) and pharmacodynamic (PD) properties of the pre- and post-switch medication. The use of temporary concomitant medications may be appropriate in some scenarios. Abrupt withdrawal of pre-switch medication may be appropriate in some instances but carries a greater risk of rebound and withdrawal symptoms than other strategies. Cross-tapering is the method most widely used in clinical practice. Paliperidone ER can be initiated without dose titration. The EU SmPC recommended dose of paliperidone ER is 6 mg/day; but doses should be individualized within the approved range of 3-12 mg/day. Higher doses may be required due to insufficient efficacy of the previous antipsychotic or in patients with acute symptoms. Recently diagnosed patients, those with renal impairment, or patients who have previously experienced tolerability issues with other antipsychotics may require lower doses. When switching from risperidone, higher doses of paliperidone ER may be required compared with risperidone. When switching from antipsychotics that have sedative and/or significant anticholinergic activity, the pre-switch antipsychotic should be tapered off gradually. Antipsychotics with less sedating and little anticholinergic activity can be tapered off over a shorter period. Temporary concomitant sedative medication may be beneficial when switching from antipsychotics with relatively higher sedative propensities. Switching from another antipsychotic to paliperidone ER requires individualized switching strategies and dosing, dependent on the characteristics of the patient and the PK and PD properties of the pre-switch medication. Cross-tapering strategies should be considered as a means of reducing the risk of rebound and withdrawal symptoms.