Second-generation antipsychotic effect on cognition in patients with schizophrenia--a meta-analysis of randomized clinical trials

In male rats, the ability of central insulin to suppress glucose production is impaired by olanzapine, whereas glucose uptake is left intact

BACKGROUND

Insulin receptors are widely expressed in the brain and may represent a crossroad between metabolic and cognitive disorders. Although antipsychotics, such as olanzapine, are the cornerstone treatment for schizophrenia, they are associated with high rates of type 2 diabetes and lack efficacy for illness-related cognitive deficits. Historically, this risk of diabetes was attributed to the weight gain propensity of antipsychotics, but recent work suggests antipsychotics can have weight-independent diabetogenic effects involving unknown brain-mediated mechanisms. Here, we examined whether antipsychotics disrupt central insulin action, hypothesizing that olanzapine would impair the well-established ability of central insulin to supress hepatic glucose production.

METHODS

Pancreatic euglycemic clamps were used to measure glucose kinetics alongside a central infusion of insulin or vehicle into the third ventricle. Male rats were pretreated with olanzapine or vehicle per our established model of acute olanzapine-induced peripheral insulin resistance. Groups included (central-peripheral) vehicle-vehicle (n = 11), insulin-vehicle (n = 10), insulin-olanzapine (n = 10) and vehicle-olanzapine (n = 8).

RESULTS

There were no differences in peripheral glucose or insulin levels. Unexpectedly, we showed that central insulin increased glucose uptake, and this effect was not perturbed by olanzapine. We replicated suppression of glucose production by insulin (clamp relative to basal: 77.9% ± 13.1%, all p < 0.05), an effect abolished by olanzapine (insulin-olanzapine: 7.7% ± 14%).

LIMITATIONS

This study used only male rats and an acute dose of olanzapine.

CONCLUSION

To our knowledge, this is the first study suggesting olanzapine may impair central insulin sensing, elucidating a potential mechanism of antipsychotic-induced diabetes and opening avenues of investigation related to domains of schizophrenia psychopathology.

Yoga as part of a package of care versus standard care for schizophrenia

BACKGROUND

Yoga is an ancient spiritual practice that originated in India and is currently accepted in the Western world as a form of relaxation and exercise. It has been of interest for people with schizophrenia to determine the efficacy of yoga delivered as a package of care versus standard care.

OBJECTIVES

To examine the effects of yoga as a package of care versus standard care.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register (latest 30 March 2017) which is based on regular searches of MEDLINE, PubMed, Embase, CINAHL, BIOSS, AMED, PsychINFO, and registries of clinical trials. We searched the references of all included studies. There are no language, date, document type, or publication status limitations for inclusion of records in the register.

SELECTION CRITERIA

All randomised controlled trials (RCTs) including people with schizophrenia comparing yoga as a package of care with standard-care control.

DATA COLLECTION AND ANALYSIS

The review authors independently selected studies, quality rated these, and extracted data. For binary outcomes, we calculated risk difference (RD) and its 95% confidence interval (CI), on an intention-to-treat (ITT) basis. For continuous data, we estimated the mean difference (MD) between groups and its CI. We employed mixed-effect and fixed-effect models for analysis. We examined heterogeneity (I² technique), assessed risk of bias for included studies, and created a 'Summary of findings' table using GRADE (Grading of Recommendations Assessment, Development and Evaluation).

MAIN RESULTS

Three studies are included in this review. All outcomes were short term (less than eight weeks). Useable data were reported for two outcomes only; leaving the study early and quality of life. None of the participants left the studies early and there was some evidence in favour of the yoga package for quality of life endpoint scores (1 RCT, n=80, MD 22.93 CI 19.74 to 26.12, low-quality evidence). Leaving the study early data were equivocal between the treatment groups (3 RCTs, n=193, RD 0.06 CI -0.01 to 0.13, medium-quality evidence, high heterogeneity). Overall, this review has an inordinate number of missing key outcomes, which included mental and global state, social functioning, physical health, adverse effects and costs of care.

AUTHORS' CONCLUSIONS

A small number of small studies were included in this review and these lacked many key outcomes. The sparse data means we cannot state with any degree of certainty if yoga delivered as a package of care is beneficial in comparison to standard care.

Yoga versus non-standard care for schizophrenia

BACKGROUND

Yoga is an ancient spiritual practice that originated in India and is currently accepted in the Western world as a form of relaxation and exercise. It has been of interest for people with schizophrenia as an alternative or adjunctive treatment.

OBJECTIVES

To systematically assess the effects of yoga versus non-standard care for people with schizophrenia.

SEARCH METHODS

The Information Specialist of the Cochrane Schizophrenia Group searched their specialised Trials Register (latest 30 March 2017), which is based on regular searches of MEDLINE, PubMed, Embase, CINAHL, BIOSIS, AMED, PsycINFO, and registries of clinical trials. We searched the references of all included studies. There are no language, date, document type, or publication status limitations for inclusion of records in the register.

SELECTION CRITERIA

All randomised controlled trials (RCTs) including people with schizophrenia and comparing yoga with non-standard care. We included trials that met our selection criteria and reported useable data.

DATA COLLECTION AND ANALYSIS

The review team independently selected studies, assessed quality, and extracted data. For binary outcomes, we calculated risk ratio (RR) and its 95% confidence interval (CI), on an intention-to-treat basis. For continuous data, we estimated the mean difference (MD) between groups and its 95% CI. We employed a fixed-effect models for analyses. We examined data for heterogeneity (I2 technique), assessed risk of bias for included studies, and created a 'Summary of findings' table for seven main outcomes of interest using GRADE (Grading of Recommendations Assessment, Development and Evaluation).

MAIN RESULTS

We were able to include six studies (586 participants). Non-standard care consisted solely of another type of exercise programme. All outcomes were short term (less than six months). There was a clear difference in the outcome leaving the study early (6 RCTs, n=586, RR 0.64 CI 0.49 to 0.83, medium quality evidence) in favour of the yoga group. There were no clear differences between groups for the remaining outcomes. These included mental state (improvement in Positive and Negative Syndrome Scale, 1 RCT, n=84, RR 0.81 CI 0.62 to 1.07, low quality evidence), social functioning (improvement in Social Occupational Functioning Scale, 1 RCT, n=84, RR 0.90 CI 0.78 to 1.04, low quality evidence), quality of life (mental health) (average change 36-Item Short Form Survey (SF-36) quality-of-life sub-scale, 1 RCT, n=69, MD -5.30 CI -17.78 to 7.18, low quality evidence), physical health, (average change WHOQOL-BREF physical-health sub-scale, 1 RCT, n=69, MD 9.22 CI -0.42 to 18.86, low quality evidence). Only one study reported adverse effects, finding no incidence of adverse events in either treatment group. There were a considerable number of missing outcomes, which included relapse, change in cognition, costs of care, effect on standard care, service intervention, disability, and activities of daily living.

AUTHORS' CONCLUSIONS

We found minimal differences between yoga and non-standard care, the latter consisting of another exercise comparator, which could be broadly considered aerobic exercise. Outcomes were largely based on single studies with limited sample sizes and short-term follow-up. Overall, many outcomes were not reported and evidence presented in this review is of low to moderate quality - too weak to indicate that yoga is superior or inferior to non-standard care control for management of people with schizophrenia.

Serum levels of second-generation antipsychotics are associated with cognitive function in psychotic disorders

OBJECTIVES

Antipsychotics are effective in treating psychosis and mood episodes; however, the effect on cognition is less known. We investigated the association between serum levels of second-generation antipsychotics (SGAs) and cognitive performance in psychosis spectrum disorders in a naturalistic setting.

METHODS

A total of 495 patients with a DSM-IV Schizophrenia and Other Psychotic Disorders (SCZ, n = 373) or Bipolar Disorder (BD, n = 122) diagnosis treated with olanzapine, quetiapine, aripiprazole or risperidone were tested neuropsychologically with concurrent measurement of the serum concentration of the drug. Linear regression was used for association analyses.

RESULTS

Attention was positively associated with the olanzapine concentration (standardised beta (β) coefficient = 0.19, P = .006), and short-term verbal memory and verbal fluency were negatively associated with the quetiapine (β = -0.24, P = .004) and risperidone (β = -0.37, P = .007) concentrations respectively.

CONCLUSIONS

The present results suggest that SGA serum concentration is associated with better attention (small effect size), and worse verbal memory (small effect size) and verbal fluency (medium effect size). These findings are in line with the notion that SGAs affect aspects of cognitive function, and suggest careful dosing in patients with severe memory and executive problems.

Antipsychotic-induced Hdac2 transcription via NF-κB leads to synaptic and cognitive side effects

Antipsychotic drugs remain the standard for schizophrenia treatment. Despite their effectiveness in treating hallucinations and delusions, prolonged exposure to antipsychotic medications leads to cognitive deficits in both schizophrenia patients and animal models. The molecular mechanisms underlying these negative effects on cognition remain to be elucidated. Here we demonstrate that chronic antipsychotic drug exposure increases nuclear translocation of NF-κB in both mouse and human frontal cortex, a trafficking event triggered via 5-HT_2A-receptor-dependent downregulation of the NF-κB repressor IκBα. This upregulation of NF-κB activity led to its increased binding at the Hdac2 promoter, thereby augmenting Hdac2 transcription. Deletion of HDAC2 in forebrain pyramidal neurons prevented the negative effects of antipsychotic treatment on synaptic remodeling and cognition. Conversely, virally mediated activation of NF-κB signaling decreased cortical synaptic plasticity via HDAC2. Together, these observations may aid in developing therapeutic strategies to improve the outcome of schizophrenia treatment.

Antipsychotics influence Toll-like receptor (TLR) expression and its relationship with cognitive functions in schizophrenia

Increasing evidence suggests that altered immune functions are related to the pathophysiology of schizophrenia. Relatively little information is available on Toll-like receptors (TLRs), which are implicated in the recognition of molecular patterns associated with pathogens and internal cellular damage signals. By using immunophenotyping and flow cytometry, we investigated TLRs in CD14+ monocytes, CD4+CD25+Foxp3+ regulatory T cells (T_reg), and CD3+CD4+CD25+ activated T cells (T_act) in 35 drug-naïve patients with schizophrenia before and after an 8-week period of antipsychotic treatment with risperidone or olanzapine. As compared with 30 healthy control individuals, drug-naïve patients with schizophrenia exhibited an increased percentage of TLR4+ and TLR5+ monocytes and TLR5+ T_reg/T_act cells. At the end of the treatment period, we observed normalized TLR4+ monocytes and an up-regulation of TLR2+ monocytes and T_reg/T_act cells. Mean fluorescent intensity values, indicating receptor density, were consistent with these findings. In the drug-naïve state, but not after treatment, higher percentages of TLR4+ and TLR5+ monocytes were correlated with more severe cognitive deficits. Positive, negative, and general clinical symptoms were not associated with TLRs. There were no significant differences between patients receiving olanzapine and risperidone. These results indicate that abnormal expression of TLRs can be detected in the earliest stage of schizophrenia, which is modulated by antipsychotics. Immunological alterations in unmedicated schizophrenia patients may be linked to cognitive deficits.

Dopamine D4 receptor stimulation contributes to novel object recognition: Relevance to cognitive impairment in schizophrenia

Several atypical antipsychotic drugs (APDs) have high affinity for the dopamine (DA) D₄ receptor, but the relevance to the efficacy for the treatment of cognitive impairment associated with schizophrenia (CIAS) is poorly understood. The aim of this study was to investigate the effects of D₄ receptor stimulation or blockade on novel object recognition (NOR) in normal rats and on the sub-chronic phencyclidine (PCP)-induced novel object recognition deficit. The effect of the D₄ agonist, PD168077, and the D₄ antagonist, L-745,870, were studied alone, and in combination with clozapine and lurasidone. In normal rats, L-745,870 impaired novel object recognition, whereas PD168077 had no effect. PD168077 acutely reversed the sub-chronic phencyclidine-induced novel object recognition deficit. Co-administration of a sub-effective dose (SED) of PD168077 with a sub-effective dose of lurasidone also reversed this deficit, but a sub-effective dose of PD168077 with a sub-effective dose of clozapine, a more potent D₄ antagonist than lurasidone, did not reverse the sub-chronic phencyclidine-induced novel object recognition deficit. At a dose that did not induce a novel object recognition deficit, L-745,870 blocked the ability of clozapine, but not lurasidone, to reverse the novel object recognition deficit. D₄ receptor agonism has a beneficial effect on novel object recognition in sub-chronic PCP-treated rats and augments the cognitive enhancing efficacy of an atypical antipsychotic drug that lacks affinity for the D₄ receptor, lurasidone.

Sleep deprivation as an experimental model system for psychosis: Effects on smooth pursuit, prosaccades, and antisaccades

Current antipsychotic medications fail to satisfactorily reduce negative and cognitive symptoms and produce many unwanted side effects, necessitating the development of new compounds. Cross-species, experimental behavioural model systems can be valuable to inform the development of such drugs. The aim of the current study was to further test the hypothesis that controlled sleep deprivation is a safe and effective model system for psychosis when combined with oculomotor biomarkers of schizophrenia. Using a randomized counterbalanced within-subjects design, we investigated the effects of 1 night of total sleep deprivation in 32 healthy participants on smooth pursuit eye movements (SPEM), prosaccades (PS), antisaccades (AS), and self-ratings of psychosis-like states. Compared with a normal sleep control night, sleep deprivation was associated with reduced SPEM velocity gain, higher saccadic frequency at 0.2 Hz, elevated PS spatial error, and an increase in AS direction errors. Sleep deprivation also increased intra-individual variability of SPEM, PS, and AS measures. In addition, sleep deprivation induced psychosis-like experiences mimicking hallucinations, cognitive disorganization, and negative symptoms, which in turn had moderate associations with AS direction errors. Taken together, sleep deprivation resulted in psychosis-like impairments in SPEM and AS performance. However, diverging somewhat from the schizophrenia literature, sleep deprivation additionally disrupted PS control. Sleep deprivation thus represents a promising but possibly unspecific experimental model that may be helpful to further improve our understanding of the underlying mechanisms in the pathophysiology of psychosis and aid the development of antipsychotic and pro-cognitive drugs.

RP5063, an atypical antipsychotic drug with a unique pharmacologic profile, improves declarative memory and psychosis in mouse models of schizophrenia

Various types of atypical antipsychotic drugs (AAPDs) modestly improve the cognitive impairment associated with schizophrenia (CIAS). RP5063 is an AAPD with a diverse and unique pharmacology, including partial agonism at dopamine (DA) D₂, D₃, D₄, serotonin (5-HT)_1A, and 5-HT_2A receptors (Rs), full agonism at α₄β₂ nicotinic acetylcholine (ACh)R (nAChR), and antagonism at 5-HT_2B, 5-HT₆, and 5-HT₇Rs. Most atypical APDs are 5-HT_2A inverse agonists. The efficacy of RP5063 in mouse models of psychosis and episodic memory were studied. RP5063 blocked acute phencyclidine (PCP)-as well as amphetamine-induced hyperactivity, indicating antipsychotic activity. Acute administration of RP5063 significantly reversed subchronic (sc)PCP-induced impairment in novel object recognition (NOR), a measure of episodic memory, but not reversal learning, a measure of executive function. Co-administration of a sub-effective dose (SED) of RP5063 with SEDs of a 5-HT₇R antagonist, a 5-HT_1BR antagonist, a 5-HT_2AR inverse agonist, or an α₄β₂ nAChR agonist, restored the ability of RP5063 to ameliorate the NOR deficit in scPCP mice. Pre-treatment with a 5-HT_1AR, a D₄R, antagonist, but not an α₄β₂ nAChR antagonist, blocked the ameliorating effect of RP5063. Further, co-administration of scRP5063 prior to each dose of PCP prevented the effect of PCP to produce a deficit in NOR for one week. RP5063, given to scPCP-treated mice for one week restored NOR for one week only. Acute administration of RP5063 significantly increased cortical DA efflux, which may be critical to some of its cognitive enhancing properties. These results indicate that RP5063, by itself, or as an adjunctive treatment has a multifaceted basis for improving some cognitive deficits associated with schizophrenia.

Brexpiprazole for the treatment of schizophrenia

INTRODUCTION

Limited efficacy on negative and cognitive symptoms and adverse effects of current antipsychotics raise the need of developing new antipsychotics. Brexpiprazole, a new antipsychotic drug approved by the U.S. Food and Drug Administration in July 2015 for the treatment of schizophrenia, is a novel serotonin-dopamine receptor modulator with partial agonist activity at serotonin 1A (5-HT_1A) and D_2/3 receptors. Areas covered: We reviewed brexpiprazole related in vitro and in vivo studies, including phase II and phase III clinical trials in this article. Brexpiprazole showed significant improvement of psychotic symptoms for patients with schizophrenia in clinical trials. Most of the clinical trials demonstrated the antipsychotic effect of brexpiprazole using Positive and Negative Syndrome Scale (PANSS) in acute schizophrenia patients, and found that higher doses (2-4 mg daily) of brexpiprazole had better outcomes. In short-term trials, brexpiprazole did not show benefit for cognitive function in 6 weeks. Insomnia, akathisia, headache, and agitation were the most frequently recorded adverse events. Expert commentary: Brexpiprazole showed better efficacy than placebo in acute phase of schizophrenia. Long-term studies are needed to investigate the efficacy of brexpiprazole for cognitive function as well as the strength and weakness of brexpiprazole among current antipsychotic drugs.

Efficacy and Safety of Brexpiprazole (OPC-34712) as Maintenance Treatment in Adults with Schizophrenia: a Randomized, Double-Blind, Placebo-Controlled Study

Background

Brexpiprazole has previously demonstrated efficacy in acute schizophrenia trials. The objective of this trial was to assess the efficacy, safety, and tolerability of maintenance treatment with brexpiprazole in adults with schizophrenia.

Methods

Patients with an acute exacerbation of psychotic symptoms were converted to brexpiprazole (1-4mg/d) over 1 to 4 weeks and entered a single-blind stabilization phase. Those patients who met stability criteria for 12 weeks were randomized 1:1 to double-blind maintenance treatment with either brexpiprazole (at their stabilization dose) or placebo for up to 52 weeks. The primary efficacy endpoint was the time from randomization to impending relapse. Safety and tolerability were also assessed.

Results

A total of 524 patients were enrolled, 202 of whom were stabilized on brexpiprazole and randomized to brexpiprazole (n=97) or placebo (n=105). Efficacy was demonstrated at a prespecified interim analysis (conducted after 45 events), and so the trial was terminated early. The final analysis showed that time to impending relapse was statistically significantly delayed with brexpiprazole treatment compared with placebo (P<.0001, log-rank test). The hazard ratio for the final analysis was 0.292 (95% confidence interval: 0.156, 0.548); mean dose at last visit, 3.6mg. The proportion of patients meeting the criteria for impending relapse was 13.5% with brexpiprazole and 38.5% with placebo (P<.0001). During the maintenance phase, the incidence of adverse events was comparable to placebo.

Conclusions

or patients with schizophrenia already stabilized on brexpiprazole, maintenance treatment with brexpiprazole was efficacious, with a favorable safety profile.

Modality shift effect in psychiatric disorders - a new look at an old paradigm

BACKGROUND

There is a long tradition of reaction time studies in experimental psychopathology. Even though a diminishing interest in this paradigm has been seen over the last years, it is in line with more recent biological approaches to examine psychiatric disorders cross-diagnostically.

METHODS

Patients (n=95) with a positive subtype of schizophrenia (n=22), a negative subtype of schizophrenia (n=18), a full major depressive episode (n=19), a full manic episode (n=16), or a mood disorder in remission (n=20) and subjects with no known psychiatric disorder (n=30), respectively, participated in a computer-based reaction time test consisting of four trials with 55 short visual and auditory stimuli presented in a random sequence. Each participant's median reaction time in milliseconds to light stimuli ipsimodal (light preceded by light) and cross-modal (light preceded by tone) and the difference between the two conditions (i.e. cross-modal retardation (CMR) to light) were recorded. Likewise, the median reaction time to tone stimuli ipsimodal and cross-modal and the difference between the two (CMR to tone) were recorded.

RESULTS

Patient groups performed worse than the control group, with the exception of the group of patients with mood disorders in remission in both CMRs. When comparing patient groups, the schizophrenia negative subtype performed worse than the remission group in both CMRs.

CONCLUSIONS

Our data support newer theories about underlying pathophysiological mechanisms and observable behavioural phenomena occurring across the different diagnostic categories, thereby supporting a dimensional approach in the diagnosis and clinical management.

Anticholinergic burden in schizophrenia and ability to benefit from psychosocial treatment programmes: a 3-year prospective cohort study

BACKGROUND

Many medications administered to patients with schizophrenia possess anticholinergic properties. When aggregated, pharmacological treatments may result in a considerable anticholinergic burden. The extent to which anticholinergic burden has a deleterious effect on cognition and impairs ability to participate in and benefit from psychosocial treatments is unknown.

METHOD

Seventy patients were followed for approximately 3 years. The MATRICS consensus cognitive battery (MCCB) was administered at baseline. Anticholinergic burden was measured with the Anticholinergic Cognitive Burden (ACB) scale. Ability to benefit from psychosocial programmes was measured using the DUNDRUM-3 Programme Completion Scale (D-3) at baseline and follow-up. Psychiatric symptoms were measured using the PANSS. Total antipsychotic dose was measured using chlorpromazine equivalents. Functioning was measured using the Social and Occupational Functioning Assessment Scale (SOFAS).

RESULTS

Mediation analysis found that the influence of anticholinergic burden on ability to participate and benefit from psychosocial programmes was completely mediated by the MCCB. For every 1-unit increase on the ACB scale, change scores for DUNDRUM-3 decreased by -0.27 points. This relationship appears specific to anticholinergic burden and not total antipsychotic dose. Moreover, mediation appears to be specific to cognition and not psychopathology. Baseline functioning also acted as mediator but only when MCCB was not controlled for.

CONCLUSIONS

Anticholinergic burden has a significant impact on patients' ability to participate in and benefit from psychosocial treatment programmes. Physicians need to be mindful of the cumulative effect that medications can have on patient cognition, functional capacity and ability to benefit from psychosocial treatments.

Serum brain-derived neurotrophic factor levels associate with cognitive improvement in patients with schizophrenia treated with electroacupuncture

Accumulating evidence supports that acupuncture has been successfully used for the treatment of neurological disorders to improve cognitive function. This study was set to evaluate the efficacy of electroacupuncture (EA, using two acupoints: Baihui and Shenting) on clinical symptoms, cognitive function and brain-derived neurotrophic factor (BDNF) levels in patients with schizophrenia. Sixty-one inpatients diagnosed schizophrenia with DSM-IV criteria were recruited. The participants were randomly divided into an experimental group (n=30) and a control group (n=31). The patients were evaluated using the Positive and Negative Symptom Scale (PANSS), the Wisconsin Card Sorting Test (WCST) and Wechsler Memory Scale (WMS) at baseline and after EA treatment. There were no significant differences in the PANSS scores and serum BDNF levels between the experimental group and the control group, either at baseline or at the end of the 4-week study period. However, the EA treatment appeared to have significant benefits on memory and moderate benefits on executive functions and problem solving. Significant positive correlation was observed between the increase of BDNF levels and memory improvement after EA treatment. Our results indicated that EA treatment could improve cognitive function, and the cognitive benefits positively associate with serum BDNF levels in patients with schizophrenia.

General and social cognition in remitted first-episode schizophrenia patients: a comparative study

The aim of this paper was to investigate whether both neurocognitive and social cognitive performances were different between remitted first-episode schizophrenia patients, non-remitters and healthy controls (HC). We assessed social cognition (Degraded Facial Affect Recognition Task-DFAR and Emotional Mentalizing Task-EMT) and neurocognition (Wechsler Adult Intelligence Scale and Word Learning Test-WLT) in 174 remitted first-episode schizophrenia patients, 110 non-remitted first-episode schizophrenia patients and 320 HC. Multivariate analyses of variance with age, gender and IQ as covariates (MANCOVA) were performed to compare mean cognitive test scores between the three groups. Remitted first-episode schizophrenia patients performed significantly worse than HC only in one verbal memory task (WLT immediate recall; p = 0.004); in the same test, they were significantly better than non-remitters (p = 0.027). Non-remitted first-episode schizophrenia patients, differently from remitters, performed significantly worse than HC in terms of social cognition (EMT-p < 0.05 and DFAR-p < 0.05). Remitted first-episode schizophrenia patients presented worse cognitive performance than HC in verbal memory tasks, but not in facial affect recognition and in ToM, while non-remitters did; these results suggest that neurocognitive deficits are the core hallmark of schizophrenia and that social cognition is relatively unaffected in remitted patients after their first episode.

Performance of Mini-Mental State Examination (MMSE) in long-stay patients with schizophrenia or schizoaffective disorders in a psychiatric institute

Studies have found that age and education were associated with cognition in older adults. However, little is known how clinical factors (e.g. age of illness onset, length of hospital stay, type of antipsychotic medications, and duration of illness) are associated with cognitive functioning in patients with schizophrenia. This study aimed to examine the influence of socio-demographic and clinical factors on cognitive domains measured using Mini-Mental State Examination (MMSE) among patients with schizophrenia or schizoaffective disorders residing in a psychiatric institute in Singapore. A single-phase interview was conducted at the Institute of Mental Health (IMH) in patients diagnosed with schizophrenia or schizoaffective disorders (n=110). MMSE was administered to all participants. Data on socio-demographic characteristics, smoking, alcohol consumption, and medical history were collected. Age, gender, and level of education were significantly associated with MMSE scores. After adjusting for all socio-demographic correlates, longer length of hospital stay remained significant in predicting lower MMSE scores. Length of hospital stay was independently associated with cognitive functioning. Early interventions for cognition such as physical and mental exercises should be implemented for better prognosis.

Drugs, games, and devices for enhancing cognition: implications for work and society

As work environments change, the demands on working people change. Cognitive abilities in particular are becoming progressively more important for work performance and successful competition in a global environment. However, work-related stress, performance over long hours, lack of sleep, shift work, and jet lag affect cognitive functions. Therefore, an increasing number of healthy people are reported to use cognitive-enhancing drugs, as well as other interventions, such as noninvasive brain stimulation, to maintain or improve work performance. This review summarizes research on pharmacological and technical methods as well as cognitive training, including game apps for the brain, in healthy people. In neuropsychiatric disorders, impairments in cognitive functions can drastically reduce the chances of returning to work; therefore, this review also summarizes findings from pharmacological and cognitive-training studies in neuropsychiatric disorders.

Allosteric modulation of cholinergic system: Potential approach to treating cognitive deficits of schizophrenia

Schizophrenia is a psychiatric disorder affecting approximately 1% of the population worldwide and is characterised by the presence of positive and negative symptoms and cognitive deficits. Whilst current therapeutics ameliorate positive symptoms, they are largely ineffective in improving negative symptoms and cognitive deficits. The cholinergic neurotransmitter system heavily influences cognitive function and there is evidence that implicates disruption of the central cholinergic system in schizophrenia. Historically, targeting the cholinergic system has been impeded by poor selectivity leading to intolerable side effects warranting the need to develop more targeted therapeutic compounds. In this review we will summarise evidence supporting the roles of the cholinergic system, particularly the muscarinic M₁ receptor, in the pathophysiology of schizophrenia and discuss the potential of a promising new class of candidate compounds, allosteric ligands, for addressing the difficulties involved in targeting this system. The body of evidence presented here highlights the dysfunction of the cholinergic system in schizophrenia and that targeting this system by taking advantage of allosteric ligands is having clinically meaningful effect on cognitive deficits.

Prevalence and predictors of treatment dropout from physical activity interventions in schizophrenia: a meta-analysis

OBJECTIVE

Physical activity interventions have been shown to improve the health of people with schizophrenia, yet treatment dropout poses an important challenge in this population, and rates vary substantially across studies. We conducted a meta-analysis to investigate the prevalence and predictors of treatment dropout in physical activity interventions in people with schizophrenia.

METHOD

We systematically searched major electronic databases from inception until August 2015. Randomized controlled trials of physical activity interventions in people with schizophrenia reporting dropout rates were included. Two independent authors conducted searches and extracted data. Random-effects meta-analysis and meta-regression analyses were conducted.

RESULTS

In 19 studies, 594 patients with schizophrenia assigned to exercise interventions were investigated (age=37.2 years, 67.5% male, range=37.5%-100%). Trim and fill adjusted treatment dropout rate was 26.7% [95% confidence interval (CI)=19.7%-35.0%], which is more than double than in nonactive control interventions (odds ratio=2.15, 95% CI=1.29-3.58, P=.003). In the multivariate regression, qualification of the professional delivering the intervention (β=-1.06, 95% CI=-1.77 to -0.35, P=.003) moderated treatment dropout rates, while continuous supervision of physical activity approached statistical significance (P=.05).

CONCLUSIONS

Qualified professionals (e.g., physical therapists/exercise physiologists) should prescribe supervised physical activity for people with schizophrenia to enhance adherence, improve psychiatric symptoms and reduce the onset and burden of cardiovascular disease.

Does cognitive impairment in treatment-resistant and ultra-treatment-resistant schizophrenia differ from that in treatment responders?

This study aimed to investigate whether cognitive impairment is more pronounced in people with treatment-resistant schizophrenia compared with those who respond well to first-line antipsychotic medication. Fifty-one patients with schizophrenia were assigned to one of three groups dependent on their clinical history: (i) 16 people who had responded well to first-line antipsychotic medication, (ii) 20 people who were treatment-resistant but responding to clozapine monotherapy, (iii) 15 people who were ultra-treatment-resistant/clozapine-resistant but responding to antipsychotic polypharmacy. Twenty-two controls were also recruited. Groups were matched for age, sex, disease duration and psychopathology. All participants undertook a computerised battery of neuropsychological tests that assessed multiple cognitive domains. Raw data were converted to z-scores, and test performance was compared between groups. People with schizophrenia performed significantly worse than controls in the majority of neuropsychological tests, with verbal memory, sustained attention, and sensorimotor the most commonly impaired domains. No significant differences in performance between people deemed to be treatment-resistant or ultra-treatment-resistant, and those who responded well to first-line antipsychotic medication were observed. There was no significant relationship between antipsychotic dose and scores on any of the neuropsychological tests. Cognitive impairment is a central feature of schizophrenia, but our results suggest that treatment-resistance may not be associated with more severe deficits.

Cognitive impairment in schizophrenia: the great unmet need

Cognitive impairment in schizophrenia is present in almost all persons with the disorder and can be a substantial obstacle to efforts in the recovery process. In clinical research, cognition is assessed through neuropsychological testing as well as by different types of structured instruments focusing on function. Although nonpharmacological interventions such as cognitive remediation have been therapeutic, particularly in combination with vocational rehabilitation and supported employment, these modalities are not always easy to access. Pharmacological interventions are in development and have principally focused on the dopamine, glutamate, and acetylcholine neurotransmitter systems, aiming to target the dorsolateral prefrontal cortex and its interactions with other brain regions.

Schizophrenia

Schizophrenia is a chronic psychiatric disorder with a heterogeneous genetic and neurobiological background that influences early brain development, and is expressed as a combination of psychotic symptoms - such as hallucinations, delusions and disorganization - and motivational and cognitive dysfunctions. The mean lifetime prevalence of the disorder is just below 1%, but large regional differences in prevalence rates are evident owing to disparities in urbanicity and patterns of immigration. Although gross brain pathology is not a characteristic of schizophrenia, the disorder involves subtle pathological changes in specific neural cell populations and in cell-cell communication. Schizophrenia, as a cognitive and behavioural disorder, is ultimately about how the brain processes information. Indeed, neuroimaging studies have shown that information processing is functionally abnormal in patients with first-episode and chronic schizophrenia. Although pharmacological treatments for schizophrenia can relieve psychotic symptoms, such drugs generally do not lead to substantial improvements in social, cognitive and occupational functioning. Psychosocial interventions such as cognitive-behavioural therapy, cognitive remediation and supported education and employment have added treatment value, but are inconsistently applied. Given that schizophrenia starts many years before a diagnosis is typically made, the identification of individuals at risk and those in the early phases of the disorder, and the exploration of preventive approaches are crucial.

Yoga versus standard care for schizophrenia

BACKGROUND

Yoga is an ancient spiritual practice that originated in India and is currently accepted in the Western world as a form of relaxation and exercise. It has been of interest for people with schizophrenia to determine its efficacy as an adjunct to standard-care treatment.

OBJECTIVES

To examine the effects of yoga versus standard care for people with schizophrenia.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register (November 2012 and January 29, 2015), which is based on regular searches of MEDLINE, PubMed, EMBASE, CINAHL, BIOSIS, AMED, PsycINFO, and registries of clinical trials. We searched the references of all included studies. There were no language, date, document type, or publication status limitations for inclusion of records in the register.

SELECTION CRITERIA

All randomised controlled trials (RCTs) including people with schizophrenia comparing yoga to standard-care control.

DATA COLLECTION AND ANALYSIS

The review team independently selected studies, quality rated these, and extracted data. For binary outcomes, we calculated risk ratio (RR) and its 95% confidence interval (CI), on an intention-to-treat basis. For continuous data, we estimated the mean difference (MD) between groups and its 95% CI. We employed mixed-effect and fixed-effect models for analyses. We examined data for heterogeneity (I(2) technique), assessed risk of bias for included studies, and created 'Summary of findings' tables using GRADE (Grading of Recommendations Assessment, Development and Evaluation).

MAIN RESULTS

We included eight studies in the review. All outcomes were short term (less than six months). There were clear differences in a number of outcomes in favour of the yoga group, although these were based on one study each, with the exception of leaving the study early. These included mental state (improvement in Positive and Negative Syndrome Scale, 1 RCT, n = 83, RR 0.70 CI 0.55 to 0.88, medium-quality evidence), social functioning (improvement in Social Occupational Functioning Scale, 1 RCT, n = 83, RR 0.88 CI 0.77 to 1, medium-quality evidence), quality of life (average change 36-Item Short Form Survey (SF-36) quality-of-life subscale, 1 RCT, n = 60, MD 15.50, 95% CI 4.27 to 26.73, low-quality evidence), and leaving the study early (8 RCTs, n = 457, RR 0.91 CI 0.6 to 1.37, medium-quality evidence). For the outcome of physical health, there was not a clear difference between groups (average change SF-36 physical-health subscale, 1 RCT, n = 60, MD 6.60, 95% CI -2.44 to 15.64, low-quality evidence). Only one study reported adverse effects, finding no incidence of adverse events in either treatment group. This review was subject to a considerable number of missing outcomes, which included global state, change in cognition, costs of care, effect on standard care, service intervention, disability, and activities of daily living.

AUTHORS' CONCLUSIONS

Even though we found some positive evidence in favour of yoga over standard-care control, this should be interpreted cautiously in view of outcomes largely based each on one study with limited sample sizes and short-term follow-up. Overall, many outcomes were not reported and evidence presented in this review is of low to moderate quality - -too weak to indicate that yoga is superior to standard-care control for the management of schizophrenia.

Epigenetic signaling in schizophrenia

Histone modifications and DNA methylation represent central dynamic and reversible processes that regulate gene expression and contribute to cellular phenotypes. These epigenetic marks have been shown to play fundamental roles in a diverse set of signaling and behavioral outcomes. Psychiatric disorders such as schizophrenia and depression are complex and heterogeneous diseases with multiple and independent factors that may contribute to their pathophysiology, making challenging to find a link between specific elements and the underlying mechanisms responsible for the disorder and its treatment. Growing evidences suggest that epigenetic modifications in certain brain regions and neural circuits represent a key mechanism through which environmental factors interact with individual's genetic constitution to affect risk of psychiatric conditions throughout life. This review focuses on recent advances that directly implicate epigenetic modifications in schizophrenia and antipsychotic drug action.

Formulation development and systematic optimization of stabilized ziprasidone hydrochloride capsules devoid of any food effect

CONTEXT AND OBJECTIVE

The objective of the study was to develop a stable capsule formulation of ziprasidone hydrochloride which can be administered without regards to food intake.

MATERIALS AND METHODS

The unstable anhydrous form of ziprasidone hydrochloride was stabilized employing hot-melt extrusion and further optimized by 3² central composite design. The formulation was optimized after establishing acceptable ranges for response variables like disintegration time, dissolution and impurity profile. A crossover fasted and fed in vivo study was conducted in human volunteers to assess the food-effect of optimized formulation vis-à-vis the marketed brand.

RESULTS AND DISCUSSION

The optimized formulation met in-house specifications for various response variables. Further, high values of correlation coefficient vouch the adequate selection of experimental design and its high prognostic ability. In our study, no significant difference was observed between the C_max and AUC values after administration of the optimized formulation in fasted and fed states. On the contrary, there was a statistically significant increase in the C_max and AUC values after oral administration of Zeldox in fed state in comparison to fasted state.

CONCLUSIONS

The present study describes the successful development of a stable formulation of 20 mg of ziprasidone devoid of any food-effects.

The impact of motivation on cognitive performance in an animal model of the negative and cognitive symptoms of schizophrenia

Interactions between motivation and cognition are implicated in producing functional impairments and poor quality of life in psychiatric patients. This interaction, however, is not well understood at either the behavioral or neural level. We developed a procedure for mice in which a cognitive measure, sustained attention, is modulated by a motivationally relevant signal that predicts reward probability on a trial-by-trial basis. Using this paradigm, we tested the interaction between motivation and cognition in mice that model the increased striatal D2 receptor activity observed in schizophrenia patients (D2R-OE mice). In control mice, attention was modulated by signaled-reward probability. In D2R-OE mice, however, attention was not modulated by reward-related cues. This impairment was not due to any global deficits in attention or maintenance of the trial-specific information in working memory. Turning off the transgene in D2R-OE mice rescued the motivational modulation of attention. These results indicate that deficits in motivation impair the ability to use reward-related cues to recruit attention and that improving motivation improves functional cognitive performance. These results further suggest that addressing motivational impairments in patients is critical to achieving substantive cognitive and functional gains.

1,2-Benzisoxazole compounds: a patent review (2009 - 2014)

INTRODUCTION

Benzisoxazoles represent a class of heterocyclic compounds of great importance for the preparation of biologically active compounds. Benzisoxazoles are an important structure and some benzisoxazole-based medicines have been approved for human clinical use, including atypical antipsychotics (risperidone, paliperidone and iloperidone) and an anticonvulsant (zonisamide).

AREAS COVERED

This review puts emphasis on the recent progress in therapeutically attractive benzisoxazole derivatives especially 1,2-benzisoxazoles, which were published in the patent literature between 2009 and 2014. As for the class of medicines, the main focus is on atypical antipsychotics and potential therapeutic treatments for other CNS disorders. This review also covers the examples of benzisoxazole-based kinase inhibitors. Moreover, novel benzisoxazoles with significant therapeutic interest are also mentioned.

EXPERT OPINION

More recent examples of structural modification of existing drugs led to the discovery of some promising benzisoxazoles for antipsychotic use. The design of multi-target ligands is important for the manipulation of pharmacological properties and safety profiles for the use of antipsychotics. Benzisoxazoles have been widely used as pharmacophores in the search for novel drug candidates in a variety of therapeutic area. It is fair to assume that the wide and frequent use of benzisoxazoles in drug discovery and development will continue into the future.