An unblinded comparison of the clinical and cognitive effects of switching from first-generation antipsychotics to aripiprazole, perospirone or olanzapine in patients with chronic schizophrenia

Impairment of autonomic emotional response for executive function in children with ADHD: A multi-modal fNIRS and pupillometric study during the Wisconsin Card Sorting Test

OBJECTIVE

Children with attention deficit hyperactivity disorder (ADHD) often experience difficulties with emotional control and a consequent inability to perform tasks. To clarify the effects of emotional behavior on cognitive functions, we aimed to determine the association between emotional changes and executive functions in children with ADHD by measuring the pupil diameter changes associated with emotional changes.

PARTICIPANTS AND METHODS

This study included 14 children with ADHD and 10 typically developing children (TDC) aged between 10 and 16 years. During the Wisconsin Card Sorting Test (WCST), which is related to context formation and task switching among executive functions, changes in pupil diameter and frontal oxygenated hemoglobin (oxy-Hb) using functional near-infrared spectroscopy (fNIRS) were recorded simultaneously. Pupil diameter changes during "cognitive shift" and "consecutive correction" were compared between both groups.

RESULTS

During cognitive shift, the pupils of children with ADHD contracted, whereas those of the TDC were mydriatic. During consecutive correction, the pupils of children with ADHD were mydriatic, whereas those of the TDC tended to contract. These results correlated with WCST performance. Moreover, during cognitive shifts, changes in bilateral frontal blood flow were increased in TDC, but not in children with ADHD.

CONCLUSION

The locus coeruleus-norepinephrine (LC-NE) system plays an important role in pupillary diameter response. These results suggest that the LC-NE system may be dysfunctional in children with ADHD, and the system's abnormality may lead to affective abnormalities in such patients, which results in poor performance on WCST (i.e., impaired executive functions).

Place of the partial dopamine receptor agonist aripiprazole in the management of schizophrenia in adults: a Delphi consensus study

BACKGROUND

Aripiprazole is a second-generation antipsychotic, efficacious in patients with schizophrenia during acute episodes. Due to its pharmacological profile, aripiprazole may be of interest in patients with specific clinical profiles who have not been studied extensively in randomised clinical trials.

OBJECTIVES

To capture experience with aripiprazole in everyday psychiatric practice using the Delphi method in order to inform decision-making on the use of aripiprazole for the treatment of patients with schizophrenia in clinical situations where robust evidence from clinical trials is lacking.

METHODS

The scope of the survey was defined as the management of schizophrenia in adults. A systematic literature review was performed to identify the different clinical situations in which aripiprazole has been studied, and to describe the level of clinical evidence. Clinical profiles to include in the Delphi survey were selected if there was a clear interest in terms of medical need but uncertainty over the efficacy of aripiprazole. For each clinical profile retained, five to seven specific statements were generated and included in a questionnaire. The final 41-item questionnaire was proposed to a panel of 406 French psychiatrists with experience in the treatment of schizophrenia. Panellists rated their level of agreement using a Likert scale. A second round of voting on eleven items was organised to clarify points for which a consensus was not obtained in the first round.

RESULTS

Five clinical profiles were identified in the literature review (persistent negative symptoms, pregnancy, cognitive dysfunction, addictive comorbidity and clozapine resistance). Sixty-two psychiatrists participated in the first round of the Delphi survey and 33 in the second round. A consensus was obtained for 11 out of 41 items in the first round and for 9/11 items in the second round. According to the panellists' clinical experience, aripiprazole can be used as maintenance treatment for pregnant women, is relevant to preserve cognitive function and can be considered an option in patients with a comorbid addictive disorder or with persistent negative symptoms.

CONCLUSION

These findings may help physicians in choosing relevant ways to use aripiprazole and highlight areas where more research is needed to widen the evidence base.

Executive deficits in schizophrenia: mediation by processing speed and its relationships with aging

BACKGROUND

Executive deficits are a core characteristic of schizophrenia. Yet, the origin of these impairments remains unclear as they may be caused by processing slowing. This issue is of particular interest for aging insofar as cognitive aging is also associated with a decline in executive functioning and a slowing of processing speed. As schizophrenia patients' life expectancy increases, a better understanding of the origin of older patients' cognitive deficits becomes essential so that healthcare can be adapted to suit them. This study aims to determine whether processing speed mediates how schizophrenia affects executive functions and whether these relationships are moderated by age.

METHODS

Sixty-two schizophrenia patients (27 women) and 62 healthy comparison subjects matched for age (range: 18-76 years), gender and education performed neurocognitive tests to evaluate their executive functions (shifting, updating, inhibition and access) and processing speed.

RESULTS

Processing speed mediated the effect of schizophrenia on the four specific executive functions, and age moderated this mediation for shifting, updating and access, but in different ways. Age moderated the effect of processing speed on shifting, the direct effect of schizophrenia on access, and both the effect of processing speed and the direct effect of schizophrenia on updating.

CONCLUSIONS

This research highlights the need to evaluate processing speed routinely during therapeutic follow-up, as it is easy and simple to assess and appears to be at the heart of the cognitive deficits in schizophrenia. Finally, processing speed abilities yield information about the evolution of cognition with aging in schizophrenia.

Differential Effects of Aripiprazole and Amisulpride on Negative and Cognitive Symptoms in Patients With First-Episode Psychoses

INTRODUCTION

Aripiprazole is hypothesized to have an effect on negative and cognitive symptoms in schizophrenia. Likewise, amisulpride is one of the only second-generation antipsychotics with which an effect on negative symptoms is reported. In the present study, we compare the effect of aripiprazole and amisulpride in initially antipsychotic-naïve patients with first-episode psychoses.

METHODS

Psychopathology and cognitive measures from two consecutive cohorts of antipsychotic-naïve first episode psychotic patients were obtained before and after 6 weeks of antipsychotic monotherapy with either aripiprazole or amisulpride. Matched healthy controls were included to account for retest effects on the cognitive measures. Analyses of variance (repeated-measures ANOVA) were performed to detect effect of time and possible cohort^*time interactions.

RESULTS

Longitudinal data was obtained from 47 and 48 patients treated for 6 weeks with amisulpride or aripiprazole, respectively. For the Wallwork negative symptom dimension, there was a cohort^*time interaction [F _{(1, 93)} = 4.29, p = 0.041] and a significant effect of time [F _{(1, 93)} = 6.03, p = 0.016], which was driven by an improvement in patients treated with aripiprazole [t ₍₄₇₎ = 4.1, p < 0.001] and not observed in patients treated with amisulpride (p > 0.5). For the eight cognitive measures, no cohort^*time interaction was found and neither was cognitive improvement in any of the cohorts when accounting for retest effect.

CONCLUSION

Patients treated with aripiprazole improved on negative symptoms, which was not the case for patients treated with amisulpride. This may point to a general effect of a partial D2 receptor agonist on negative symptoms in patients with first-episode psychoses. There was, however, no improvement in cognitive functions.

ASHP Therapeutic Position Statement on the Use of Antipsychotic Medications in the Treatment of Adults with Schizophrenia and Schizoaffective Disorder

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

Executive functions in schizophrenia aging: Differential effects of age within specific executive functions

There are common cognitive and brain abnormalities in schizophrenia and healthy aging which may cumulate in schizophrenia aging. However, the course of executive deficits in late-life schizophrenia is still controversial as it remains unclear whether schizophrenia patients show accelerated aging. The use of specific models of executive functions might help to shed new lights on this issue. The aim of this study was then to determine how each of the four specific executive functions (shifting, updating, inhibition and access to long-term memory) is affected by aging in schizophrenia compared to healthy aging. 20 younger (age 18-34), 17 middle-aged (age 35-49) and 25 older (age 59-76) schizophrenia patients and 62 healthy comparison participants matched for gender, age and education performed a neurocognitive battery evaluating the four specific executive functions. Schizophrenia patients performed worse than comparison participants on shifting, updating and access, whereas inhibition appeared preserved. Age affected the four functions with increased degradation of shifting and access in schizophrenia patients, whereas updating and inhibition showed a normal decline with age. These results suggest a vulnerability of prefrontal and cingulate cortexes in schizophrenia aging. Moreover, as age affected the specific executive functions differently, remediation programs should be adapted to older patients. Models of specific executive functions are useful for understanding the complexity of cognition in schizophrenia and its course during later life so that healthcare can be adapted accordingly.

Aripiprazole for the treatment of psychotic symptoms in patients with dementia with Lewy bodies: a case series

PURPOSE

The core features of dementia with Lewy bodies (DLB) are cognitive fluctuations, visual hallucinations, and parkinsonian symptoms. Although there have been several reports on the efficacy of treatments for psychotic symptoms in patients with DLB, little is known regarding the treatment effects of aripiprazole. The aim of this study was to evaluate the efficacy and safety of aripiprazole for the treatment of psychotic symptoms in patients with DLB.

PATIENTS AND METHODS

We employed a 10-week, open-label study design with 11 patients who met the criteria for DLB. The patients had previously experienced persistent or intermittent delusions, hallucinations, or both for at least 1 month. Aripiprazole was initiated at a low dose (3 or 6 mg/day) and titrated to higher doses at 2-week intervals or more rapidly, as needed. The Neuropsychiatric Inventory (NPI), Brief Psychiatric Rating Scale (BPRS), and Clinical Global Impression-Severity (CGI-S) were administered at baseline and 1, 2, 4, 8, and 10 weeks later. The Simpson-Angus Scale (SAS), Clinical Dementia Rating (CDR), and Mini-Mental State Examination (MMSE) Scale were evaluated at baseline and at week 10. The NPI, CGI-S, and BPRS scores were compared between the baseline and each assessment point and between each assessment point and the one before assessment point. The SAS, CDR, and MMSE scores were compared between the baseline and the end point.

RESULTS

The mean NPI and BPRS scores improved until the fourth week; they significantly decreased at each assessment point compared to the previous one. Afterward, improvements slowed and continued without significant decrease. The median SAS scores significantly decreased at the end point compared to the baseline (P<0.05). The median MMSE score was higher at the end point than at the baseline (P<0.05).

CONCLUSION

This study showed that aripiprazole may be effective and well tolerated for the treatment of psychotic symptoms in patients with DLB.

The relationship between dopamine receptor blockade and cognitive performance in schizophrenia: a [11C]-raclopride PET study with aripiprazole

Aripiprazole's effects on cognitive function in patients with schizophrenia are unclear because of the difficulty in disentangling specific effects on cognitive function from secondary effects due to the improvement in other schizophrenic symptoms. One approach to address this is to use an intermediate biomarker to investigate the relationship between the drug's effect on the brain and change in cognitive function. This study aims to investigate aripiprazole's effect on working memory by determining the correlation between dopamine D2/3 (D2/3) receptor occupancy and working memory of patients with schizophrenia. Seven patients with schizophrenia participated in the study. Serial positron emission tomography (PET) scans with [¹¹C]raclopride were conducted at 2, 26, and 74 h after the administration of aripiprazole. The subjects performed the N-back task just after finishing the [¹¹C]raclopride PET scan. The mean (±SD) D2/3 receptor occupancies were 66.9 ± 6.7% at 2 h, 65.0 ± 8.6% at 26, and 57.7 ± 11.2% at 74 h after administering aripiprazole. Compared with performance on the zero-back condition, performance in memory-loaded conditions (one-, two-, and three-back conditions) was significantly related to D2/3 receptor occupancy by aripiprazole (error rate: ß = -2.236, t = -6.631, df = 53.947, and p = 0.001; reaction time: ß = -9.567, t = -2.808, df = 29.967, and p = 0.009). Although the sample size was relatively small, these results suggest that aripiprazole as a dopamine-partial agonist could improve cognitive function in patients with schizophrenia.

Serum levels of β-hydroxybutyrate and pyruvate, metabolic changes and cognitive function in patients with schizophrenia during antipsychotic treatment: a preliminary study

BACKGROUND

β-hydroxybutyrate (β-HB) and pyruvate have been associated with the brain energy utilization, which may play a role in the pathophysiology of schizophrenia. In this prospective study, we aim to investigate the trends of β-HB and pyruvate levels, metabolic changes, and cognitive function in schizophrenia patients receiving antipsychotic treatment.

OBJECTIVE

We recruited 38 schizophrenia patients who had been treated with antipsychotics for 12 weeks, as well as 38 healthy age- and gender-matched subjects. Blood samples were taken from the patients at baseline and week 12 to determine the serum levels of β-HB, pyruvate, and metabolic parameters, while blood samples of the healthy controls were taken at baseline. We evaluated the psychopathology using the Positive and Negative Syndrome Scale and cognitive function using the Brief Assessment of Cognition in Schizophrenia.

RESULTS

During the 12-week follow-up period, the β-HB levels in patients with schizophrenia showed a decreasing trend, particularly in those undergoing treatment with aripiprazole or ziprasidone. The serum levels of β-HB in patients at baseline and week 12 were both higher than the levels in the healthy controls. Among the schizophrenia patients, changes in β-HB were positively correlated with changes in executive function. On the other hand, serum pyruvate levels remained steady during the 12-week follow-up period, and we found no significant correlation between pyruvate changes and changes in cognitive function or clinical symptoms.

CONCLUSION

Our findings indicate that β-HB may possess a potential indicator of energy utilization and have a protective role in executive function in patients with schizophrenia. Additional longitudinal studies with a larger sample size and longer follow-up periods are necessary to identify the relationship of metabolite regulation and cognitive function during schizophrenia patients' exposure to antipsychotics.

Roman high and low avoidance rats differ in their response to chronic olanzapine treatment at the level of body weight regulation, glucose homeostasis, and cortico-mesolimbic gene expression

Olanzapine, an antipsychotic agent mainly used for treating schizophrenia, is frequently associated with body weight gain and diabetes mellitus. Nonetheless, studies have shown that not every individual is equally susceptible to olanzapine's weight-gaining effect. Therefore, Roman high and low avoidance rat strains were examined on their responsiveness to olanzapine treatment. The Roman high avoidance rat shares many behavioral and physiological characteristics with human schizophrenia, such as increased central dopaminergic sensitivity, whereas the Roman low avoidance rat has been shown to be prone to diet-induced obesity and insulin resistance. The data revealed that only the Roman high avoidance rats are susceptible to olanzapine-induced weight gain and attenuated glucose tolerance. Here it is suggested that the specific olanzapine-induced weight gain in Roman high avoidance rats could be related to augmented dopaminergic sensitivity at baseline through increased expression of prefrontal cortex dopamine receptor D1 mRNA and nucleus accumbens dopamine receptor D2 mRNA expression. Regression analyses revealed that olanzapine-induced weight gain in the Roman high avoidance rat is above all related to increased prolactin levels, whereas changes in glucose homeostasis is best explained by differences in central dopaminergic receptor expressions between strains and treatment. Our data indicates that individual differences in dopaminergic receptor expression in the cortico-mesolimbic system are related to susceptibility to olanzapine-induced weight gain.

Specific effect of a dopamine partial agonist on counterfactual learning: evidence from Gilles de la Tourette syndrome

The dopamine partial agonist aripiprazole is increasingly used to treat pathologies for which other antipsychotics are indicated because it displays fewer side effects, such as sedation and depression-like symptoms, than other dopamine receptor antagonists. Previously, we showed that aripiprazole may protect motivational function by preserving reinforcement-related signals used to sustain reward-maximization. However, the effect of aripiprazole on more cognitive facets of human reinforcement learning, such as learning from the forgone outcomes of alternative courses of action (i.e., counterfactual learning), is unknown. To test the influence of aripiprazole on counterfactual learning, we administered a reinforcement learning task that involves both direct learning from obtained outcomes and indirect learning from forgone outcomes to two groups of Gilles de la Tourette (GTS) patients, one consisting of patients who were completely unmedicated and the other consisting of patients who were receiving aripiprazole monotherapy, and to healthy subjects. We found that whereas learning performance improved in the presence of counterfactual feedback in both healthy controls and unmedicated GTS patients, this was not the case in aripiprazole-medicated GTS patients. Our results suggest that whereas aripiprazole preserves direct learning of action-outcome associations, it may impair more complex inferential processes, such as counterfactual learning from forgone outcomes, in GTS patients treated with this medication.

Developmental changes in autonomic emotional response during an executive functional task: A pupillometric study during Wisconsin card sorting test

OBJECTIVE

The autonomic nervous system has a deep relationship with the cognitive network when performing cognitive tasks. We hypothesize that autonomic emotional responses can affect cognitive function, especially executive function. The aim of this study was to clarify the involvement of the autonomic system during an executive functional task via developmental changes assessed using pupillometry.

SUBJECTS AND METHODS

Subjects were 16 healthy children and 9 healthy adults. Children were divided into 3 groups (Group A, 7-9years; Group B, 10-14years; Group C, 15-17years). Pupil diameter was recorded using an eye mark recorder during cognitive shift (CS) during the Wisconsin card sorting test (WCST). The rate of pupil variations was integrated and compared within each group, focusing on performance during CS.

RESULTS

Categories achieved (CA) in the behavioral results of WCST increased with age, with significant differences between Group A and other groups. The change of pupillary diameter was increased with CS and decreased at the correct answers after CS in adults. Changes of pupillary diameter with CS showed a linear increase with age, and the pattern of the pupillary response at the age of 10-14years was comparable to adults. The integrated rate of pupil diameter with CS increased with age, and there was a significant difference between Group A and adults. In addition, the degree of mydriasis correlated with the number of CA.

CONCLUSION

These findings suggest that autonomic emotional response play an important role as a part of the process for executive function.

MK-801-induced deficits in social recognition in rats: reversal by aripiprazole, but not olanzapine, risperidone, or cannabidiol

Deficiencies in social activities are hallmarks of numerous brain disorders. With respect to schizophrenia, social withdrawal belongs to the category of negative symptoms and is associated with deficits in the cognitive domain. Here, we used the N-methyl-D-aspartate receptor antagonist dizocilpine (MK-801) for induction of social withdrawal in rats and assessed the efficacy of several atypical antipsychotics with different pharmacological profiles as putative treatment. In addition, we reasoned that the marijuana constituent cannabidiol (CBD) may provide benefit or could be proposed as an adjunct treatment in combination with antipsychotics. Hooded Lister rats were tested in the three-chamber version for social interaction, with an initial novelty phase, followed after 3 min by a short-term recognition memory phase. No drug treatment affected sociability. However, distinct effects on social recognition were revealed. MK-801 reduced social recognition memory at all doses (>0.03 mg/kg). Predosing with aripiprazole dose-dependently (2 or 10 mg/kg) prevented the memory decline, but doses of 0.1 mg/kg risperidone or 1 mg/kg olanzapine did not. Intriguingly, CBD impaired social recognition memory (12 and 30 mg/kg) but did not rescue the MK-801-induced deficits. When CBD was combined with protective doses of aripiprazole (CBD-aripiprazole at 12 :  or 5 : 2 mg/kg) the benefit of the antipsychotic was lost. At the same time, activity-related changes in behaviour were excluded as underlying reasons for these pharmacological effects. Collectively, the combined activity of aripiprazole on dopamine D2 and serotonin 5HT1A receptors appears to provide a significant advantage over risperidone and olanzapine with respect to the rescue of cognitive deficits reminiscent of schizophrenia. The differential pharmacological properties of CBD, which are seemingly beneficial in human patients, did not back-translate and rescue the MK-801-induced social memory deficit.

Effects of aripiprazole and haloperidol on neural activation during the n-back in healthy individuals: A functional MRI study

OBJECTIVE

Antipsychotic drugs target neurotransmitter systems that play key roles in working memory. Therefore, they may be expected to modulate this cognitive function via their actions at receptors for these neurotransmitters. However, the precise effects of antipsychotic drugs on working memory function remain unclear. Most studies have been carried out in clinical populations, making it difficult to disentangle pharmacological effects from pathology-related brain activation. In this study, we aim to investigate the effects of two antipsychotic compounds on brain activation during working memory in healthy individuals. This would allow elucidation of the effects of current antipsychotic treatments on brain function, independently of either previous antipsychotic use or disease-related pathology.

METHODS

We carried out a fully counterbalanced, randomised within-subject, double-blinded and placebo-controlled, cross-over study of the effects of two antipsychotic drugs on working memory function in 17 healthy individuals, using the n-back task. Participants completed the functional MRI task on three separate occasions (in randomised order): following placebo, haloperidol, and aripiprazole. For each condition, working memory ability was investigated, and maps of neural activation were entered into a random effects general linear regression model to investigate main working memory function and linear load. Voxel-wise and region of interest analyses were conducted to attain regions of altered brain activation for each intervention.

RESULTS

Aripiprazole did not lead to any changes in neural activation compared with placebo. However, reaction time to a correct response was significantly increased following aripiprazole compared to both placebo (p=0.046) and haloperidol (p=0.02). In contrast, compared to placebo, haloperidol dampened activation in parietal (BA 7/40; left: FWE-corr. p=0.005; FWE-corr. right: p=0.007) and frontal (including prefrontal; BA 9/44/46; left: FWE-corr. p=0.009; right: FWE-corr. p=0.014) cortices and the left putamen (FWE-corr. p=0.004). Compared with aripiprazole, haloperidol dampened activation in parietal cortex (BA7/40; left: FWE-corr. p=0.034; right: FWE-corr. p=0.045) and the left putamen (FWE-corr.p=0.015). Haloperidol had no effect on working memory performance compared with placebo.

CONCLUSION

Cognitive functions are known to be impaired in schizophrenia and as such are an important target of treatments. Elucidating the mechanisms by which antipsychotic medications alter brain activation underlying cognition is essential to advance pharmacological treatment of this disorder. Studies in healthy individuals can help elucidate some of these mechanisms, whilst limiting the confounding effect of the underlying disease-related pathology. Our study provides evidence for immediate and differential effects of single-dose haloperidol and aripiprazole on brain activation during working memory in healthy individuals. We propose that these differences likely reflect their different receptor affinity profiles, although the precise mechanisms underlying these differences remain unclear.

Coadministration of tramadol with aripiprazole and venlafaxine--The effect on spatial memory functions in male rats

BACKGROUND

The impairment of memory functions is very common in patients with chronic pain, particularly in patients with existing cognitive disorders. Results of some studies confirmed that tramadol (TRM), a frequently prescribed analgesic drug, improves memory functions in humans. However, there are no studies on the effect of co-administration of TRM with antidepressants or antipsychotics on memory; therefore, the aim of this study was to evaluate the effect of concomitant use of TRM with a second generation antipsychotic-aripiprazole (ARI) and an antidepressant-venlafaxine (VEN) on memory using an animal model.

METHODS

The effect of TRM (5mg/kg)+ARI (1.5mg/kg) and TRM (5mg/kg)+VEN (20mg/kg) on memory in Wistar rats was examined using the Morris water maze test after single and chronic administration (7 and 14 days).

RESULTS

It was observed that a single and chronic administration of TRM, VEN or ARI alone, but not a combination of TRM+VEN or TRM+ARI (except for 14 days of treatment) can improve memory in rats compared to the control group. After 14 days of administration, both combinations achieved improvement similar to each drug individually and improved spatial memory in rats compared to the control animals.

CONCLUSION

It can be assumed that chronic treatment with combinations of TRM+VEN or TRM+ARI is unlikely to cause memory impairment and interfere with either any antidepressant effect of VEN or any antipsychotic effect of ARI in patients suffering from chronic pain using TRM.

Systematic Literature Review of the Methods Used to Compare Newer Second-Generation Agents for the Management of Schizophrenia: A focus on Health Technology Assessment

BACKGROUND

The challenges of comparative effectiveness to support health technology assessment (HTA) agencies are important considerations in the choices of antipsychotic medications for the treatment of schizophrenia.

OBJECTIVES

Our aim was to assess the study methods used and outcomes reported in the published literature to address the question of comparative effectiveness of newer antipsychotic agents and the adequacy and availability of evidence to support HTA agencies.

DATA SOURCE

A systematic search of the PubMed database from 1 January 2009 to 30 September 2013 was conducted to identify studies evaluating new atypical antipsychotics reporting on comparative effectiveness.

STUDY SELECTION

The systematic review comprised of studies on schizophrenia patients where at least two drugs were being compared and at least one treatment group received one of the following second-generation antipsychotics: risperidone, olanzapine, aripiprazole, paliperidone, asenapine, iloperidone, lurasidone, and quetiapine. The included studies were also required to have an efficacy, safety or economic outcome, such as Positive and Negative Syndrome Scale (PANSS) score, weight gain, resource utilization, or costs.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two reviewers (BW and GK) independently applied the inclusion criteria. Disagreements between reviewers were resolved by consensus, referring to the original sources. Information on the methodology and outcomes was collected for each included study. This included study description, head-to-head drug comparison, patient population, study methodology, statistical methods, reported outcomes, study support, and journal type.

RESULTS

A total of 198 studies were identified from electronic search methods. The largest category of studies was randomized controlled trials [RCTs] (N = 73; 36.9%), which were largely directed at the regulatory endpoint. Fewer studies were undertaken for HTA-purposes cohort studies (N = 53; 26.8%), meta-analyses (N = 32; 16.2%), economic studies (N = 14; 7.1%), and cross-sectional studies (N = 13; 6.6%). Direct head-to-head comparisons preferred by HTA were dominated by the comparison involving olanzapine and risperidone, representing 149 (75.3%) and 119 (60.1%) studies, respectively. RCTs, which are the primary study type for regulatory submissions, showed a lack of bias. Studies aimed at HTA were not as well performed. Cohort studies suffered from bias in the selection of comparison groups, lack of control for confounders, and differential dropout rates. As a group, cross-sectional studies scored poorly for bias, with a primary failure to identify a representative sample. Economic studies showed highly variable bias, with bias in the representation of effectiveness data, model assumptions without validation, and lack of sensitivity analyses.

LIMITATIONS

One limitation of this systematic review is that it only included studies from 2009 to 2013, potentially excluding some earlier comparator studies, particularly those involving first-generation antipsychotics.

CONCLUSIONS

This review of comparative effectiveness studies of second-generation antipsychotic agents for schizophrenic patients revealed a wide range of study types, study methodologies, and outcomes. For traditional efficacy outcomes and select safety outcomes, there is strong evidence from many well-conducted studies; however, there are fewer studies of types preferred by HTA with limited head-to-head comparisons and a higher risk of bias in the execution of these studies.

No difference in frontal cortical activity during an executive functioning task after acute doses of aripiprazole and haloperidol

Background: Aripiprazole is an atypical antipsychotic drug that is characterized by partial dopamine D2 receptor agonism. Its pharmacodynamic profile is proposed to be beneficial in the treatment of cognitive impairment, which is prevalent in psychotic disorders. This study compared brain activation characteristics produced by aripiprazole with that of haloperidol, a typical D2 receptor antagonist, during a task targeting executive functioning.

Methods: Healthy participants received an acute oral dose of haloperidol, aripiprazole or placebo before performing an executive functioning task while blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) was carried out.

Results: There was a tendency towards reduced performance in the aripiprazole group compared to the two other groups. The image analysis yielded a strong task-related BOLD-fMRI response within each group. An uncorrected between-group analysis showed that aripiprazole challenge resulted in stronger activation in the frontal and temporal gyri and the putamen compared with haloperidol challenge, but after correcting for multiple testing there was no significant group difference.

Conclusion: No significant group differences between aripiprazole and haloperidol in frontal cortical activation were obtained when corrected for multiple comparisons. This study is registered in ClinicalTrials.gov (identifier: 2009-016222-14).¹

Improvement of dizocilpine-induced social recognition deficits in mice by brexpiprazole, a novel serotonin-dopamine activity modulator

Cognitive impairment, including impaired social cognition, is largely responsible for the deterioration in social life suffered by patients with psychiatric disorders, such as schizophrenia and major depressive disorder (MDD). Brexpiprazole (7-{4-[4-(1-benzothiophen-4-yl)piperazin-1-yl]butoxy}quinolin-2(1H)-one), a novel serotonin-dopamine activity modulator, was developed to offer efficacious and tolerable therapy for different psychiatric disorders, including schizophrenia and adjunctive treatment of MDD. In this study, we investigated whether brexpiprazole could improve social recognition deficits (one of social cognition deficits) in mice, after administration of the N-methyl-d-aspartate (NMDA) receptor antagonist MK-801 (dizocilpine). Dosing with dizocilpine (0.1mg/kg) induced significant impairment of social recognition in mice. Brexpiprazole (0.01, 0.03, 0.1mg/kg, p.o.) significantly ameliorated dizocilpine-induced social recognition deficits, without sedation or a reduction of exploratory behavior. In addition, brexpiprazole alone had no effect on social recognition in untreated control mice. By contrast, neither risperidone (0.03mg/kg, p.o.) nor olanzapine (0.03mg/kg, p.o.) altered dizocilpine-induced social recognition deficits. Finally, the effect of brexpiprazole on dizocilpine-induced social recognition deficits was antagonized by WAY-100,635, a selective serotonin 5-HT1A antagonist. These results suggest that brexpiprazole could improve dizocilpine-induced social recognition deficits via 5-HT1A receptor activation in mice. Therefore, brexpiprazole may confer a beneficial effect on social cognition deficits in patients with psychiatric disorders.

Neurocognitive effects of aripiprazole in adolescents and young adults with schizophrenia

BACKGROUND

The use of aripiprazole has been associated with a positive influence on mood and improved cognitive skills and social interactions; however, studies of its effects on young schizophrenic patients have been limited to active symptoms.

AIMS

This prospective, open-label study investigated the neurocognitive effects of aripiprazole in adolescents and young adults with first and repeated episodes of schizophrenia.

METHODS

Twenty-three of 42 schizophrenic outpatients aged 12-26 completed a trial of aripiprazole, and its efficacy was determined using the Brief Psychiatric Rating Scale (BPRS), Clinical Global Impressions Severity (CGI-S) and WHO Quality of Life (WHOQOL) scales. Cognitive function was measured with the Cognitive Performance Test (CPT) and Wisconsin Card Sorting Test (WCST) at 4, 12 and 24 weeks of treatment.

RESULTS

Results showed statistically significant improvements in BPRS, CGI-S and WHOQOL scores in certain (but not all) subcategories of cognitive measures including CPT detectability and total errors and perseverative errors on the WCST. There were few adverse side-effects.

CONCLUSIONS

Psychotic symptoms and cognitive skills improved during treatment with aripiprazole in adolescents and young adults with schizophrenia. Patients with first psychotic episodes did better than did those with repeat episodes.

The influence of switching from risperidone to paliperidone on the extrapyramidal symptoms and cognitive function in elderly patients with schizophrenia: a preliminary open-label trial

OBJECTIVE

This study was to evaluate the effects on clinical symptoms and cognitive function of switching the treatment of elderly patients with schizophrenia from risperidone to paliperidone (PAL).

METHODS

This study was a 12-weeks, preliminary open-label trial. The subjects were 17 inpatients. Their extrapyramidal symptoms (EPS) were assessed using the Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS), Abnormal Involuntary Movement Scale (AIMS), and Barnes Akathisia Scale (BAS), and their cognitive function was assessed using the Brief Assessment Cognition in Schizophrenia: Japanese language version (BACS-J), and their clinical symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS) and Clinical Global Impression-Severity of illness scale (CGI-S) at the 0 and 12 weeks.

RESULTS

The DIEPSS and BAS significantly improved after switching from risperidone to PAL. Furthermore, improvement was found on AIMS. The mean change from baseline in z-score of the digit sequencing task was significantly increased. All items on the PANSS and CGI-S were not significant; however, changes in some cognitive function were correlated with changes in EPS.

CONCLUSIONS

The results of this study suggest the possibility that switching elderly patients from risperidone to PAL may have improved pre-existing EPS, and may also have helped improve working memory.

Pharmacological Interventions for the MATRICS Cognitive Domains in Schizophrenia: What's the Evidence?

Schizophrenia is a disabling, chronic psychiatric disorder with a prevalence rate of 0.5-1% in the general population. Symptoms include positive (e.g., delusions, hallucinations), negative (e.g., blunted affect, social withdrawal), as well as cognitive symptoms (e.g., memory and attention problems). Although 75-85% of patients with schizophrenia report cognitive impairments, the underlying neuropharmacological mechanisms are not well understood and currently no effective treatment is available for these impairments. This has led to the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) initiative, which established seven cognitive domains that are fundamentally impaired in schizophrenia. These domains include verbal learning and memory, visual learning and memory, working memory, attention and vigilance, processing speed, reasoning and problem solving, and social cognition. Recently, a growing number of studies have been conducted trying to identify the underlying neuropharmacological mechanisms of cognitive impairments in schizophrenia patients. Specific cognitive impairments seem to arise from different underlying neuropharmacological mechanisms. However, most review articles describe cognition in general and an overview of the mechanisms involved in these seven separate cognitive domains is currently lacking. Therefore, we reviewed the underlying neuropharmacological mechanisms focusing on the domains as established by the MATRICS initiative which are considered most crucial in schizophrenia.

Effect of aripiprazole on cognitive function and hyperprolactinemia in patients with schizophrenia treated with risperidone

Objective

This study aimed to assess the efficacy of aripiprazole for the management of cognitive impairments and hyperprolactinemia in patients with schizophrenia on a stable dose of risperidone.

Methods

Thirty-five subjects stabilized on risperidone (3-6 mg/day) for a minimum of 3 months were enrolled in a double-blind, placebo-controlled phase for 12 weeks and an open-label phase for another 12 weeks. Subjects were randomly assigned to receive 10 mg/day aripiprazole (n=17) or placebo (n=18). Over the following 12 weeks, the the aripiprazole group received a flexible dose of aripiprazole while tapering risperidone. At baseline, week 12, and week 24, subjects were evaluated using the Positive and Negative Syndrome Scale (PANSS), Extrapyramidal Syndrome Rating Scale (ESRS), and standardized neuropsychological assessments. Serum prolactin levels were checked at baseline, week 1, week 2, and week 24.

Results

The mean change in total PANSS and cognitive function test scores between baseline and endpoint were similar in the aripiprazole and placebo groups. Scores on the ESRS and negative subscale of PANSS differed significantly between groups in both phases of the study (p<0.05), indicating a positive effect of aripiprazole. Compared with placebo, aripiprazole significantly reduced mean baseline serum prolactin levels within 1 week (p=0.015).

Conclusion

Adjunctive treatment with and switching to aripiprazole were not associated with improved cognitive function in patients with schizophrenia receiving risperidone; however, aripiprazole treatment decreased negative symptoms and risperidone-induced motor side effects and lowered serum prolactin levels.

The relationship between antipsychotic D2 occupancy and change in frontal metabolism and working memory : A dual [(11)C]raclopride and [(18) F]FDG imaging study with aripiprazole

RATIONALE

The effects of aripiprazole on cognitive function are obscure, possibly due to the difficulty in disentangling the specific effects on cognitive function from effects secondary to the improvement of other schizophrenic symptoms. This prompts the necessity of using an intermediate biomarker relating the drug effect on the brain to change in cognitive function.

OBJECTIVES

To explore the effect of aripiprazole on cognitive function, we measured changes in frontal metabolism as an intermediate biomarker and sought to determine its relationship with D2 receptor occupancy and changes in working memory.

METHODS

Fifteen healthy male volunteers participated in the study. Serial positron emission tomography (PET) scans with [(11)C]raclopride and [(18) F]FDG were conducted 1 day before and 2 days after the administration of aripiprazole. The subjects performed the N-back task just after finishing the [(18) F]FDG scan.

RESULTS

The mean (±SD) D2 receptor occupancies were 22.2 ± 16.0 % in the 2 mg group, 35.5 ± 3.6 % in the 5 mg group, 63.2 ± 9.9 % in the 10 mg group and 72.8 ± 2.1 % in the 30 mg group. The frontal metabolism was significantly decreased after the administration of aripiprazole (t = 2.705, df = 14, p = 0.017). Greater striatal D2 receptor occupancy was related to greater decrease in frontal metabolism (r = -0.659, p = 0.010), and greater reduction in frontal metabolism was associated with longer reaction times (r = -0.597, p = 0.019) under the greatest task load.

CONCLUSIONS

Aripiprazole can affect cognitive function and alter frontal metabolic function. The changes in these functions are linked to greater D2 receptor occupancy. This suggests that it may be important to find the lowest effective dose of aripiprazole in order to prevent adverse cognitive effects.

Aripiprazole improves various cognitive and behavioral impairments after traumatic brain injury: a case report

Various types of cognitive and behavioral impairments occur after traumatic brain injury. We present a case exhibiting psychotic symptoms such as irritability, dysphoria, anxiety and insomnia with severe brain dysfunction due to a right temporal lobe contusion incurred in a traffic accident. The patient did not sufficiently respond to rehabilitation or treatment with any pharmacotherapy. In the present case, aripiprazole dramatically improved the patient's symptoms and cognitive function. We evaluated the case using the Wechsler Adult Intelligence Scale-Revised and the Wechsler Memory Scale Revised between baseline and 5 years later.

Deficit status in bipolar disorder: investigation on prevalence rate and description of seven cases

OBJECTIVE

While the Kraepelinian dichotomy explicitly distinguishes between schizophrenia and bipolar disorder, it remains unclear as to whether a deficit form of bipolar disorder exists.

METHOD

We conducted a study to investigate the prevalence rate of the deficit form of bipolar disorder; the criteria of which were basically adopted by the original proposal for schizophrenia that described the predominance of negative symptoms for over a year. Moreover, we presented a series of cases with "deficit" bipolar disorder to characterize its clinical pictures in detail.

RESULTS

Consecutive outpatients who visited one psychiatric hospital in Tokyo, Japan in March 2007 were evaluated cross-sectionally. Additionally, medical charts of inpatients who were hospitalized in the same hospital between April 2006 and March 2007 were also thoroughly reviewed. Of 494 patients, 7 patients (1.4%; 10.9% of 64 bipolar cases) fulfilled the criteria for bipolar disorder with deficit syndrome. Seven "deficit" cases had a mean±SD age of 61±5 year-old with the age at onset being 25±8 year-old. In addition to pervasive negative symptoms, they exhibited evidence of cognitive impairments close to the magnitude of what is usually noted in schizophrenia (i.e. a mean±SD total IQ score of 80±9 in the Wechsler Adult Intelligence Scale and 0.4±0.5 in the Wisconsin Card Sorting Test, categories achieved).

CONCLUSION

Although preliminary, the evidence on deficit status in patients with bipolar disorder that we found in this study appears more consistent with recent evidence and challenges the Kraepelinian dichotomy that reserves deficit status solely to schizophrenia patients.

Cognitive effects of a single dose of atypical antipsychotics in healthy volunteers compared with placebo or haloperidol

Cognitive dysfunction in patients with schizophrenia is a strong correlate of poor outcome than any other symptom domain. To have greater knowledge about the effects of antipsychotics on cognitive function, subjects of this study were healthy volunteers who had no confounding variables typically found in patients with schizophrenia. The cognitive function of healthy volunteers in response to single doses of haloperidol, risperidone, aripiprazole, and amisulpride in a double-blind placebo-controlled trial was investigated. Assessments for the computerized neurocognitive test, mental and physical sedation, and extrapyramidal symptoms were performed within 1 week before (baseline) and approximately 4 hours after drug administration. Compared to the placebo, single administration of amisulpride at 400 mg in healthy volunteers enhanced word fluency test performance and remained intact after controlling for sedation and extrapyramidal symptoms. Significant improvement in some measurements of the computerized neurocognitive test was also observed in each antipsychotic-treated group but may have been related to practice effect. These findings suggest that amisulpride may have cognitive-enhancing effects in healthy volunteers.

The influence of switching from haloperidol decanoate depot to risperidone long-acting injection on the clinical symptoms and cognitive function in schizophrenia

OBJECTIVE

This study was a comparative investigation of the effects on clinical symptoms and cognitive function of switching the treatment of schizophrenia patients from haloperidol decanoate depot to risperidone long-acting injection (RLAI) compared with a control group that continued receiving haloperidol decanoate depot.

METHODS

This study was a 24-week, non-randomized, non-double blind, open-label trial. The subjects' clinical symptoms were assessed using the Positive and Negative Syndrome Scale, and their cognitive function was assessed using the Wisconsin Card Sorting Test: Keio Version to assess executive function and the St. Marianna University School of Medicine's Computerized Memory Test to assess memory and concentration at 0 and 24 weeks.

RESULTS

The mean change from baseline in the number of categories achieved at the second stage of the Wisconsin Card Sorting Test: Keio Version was significantly greater in the RLAI group than in the control group. The mean changes from baseline in the individual St. Marianna University School of Medicine's Computerized Memory Tests were significantly greater in the RLAI group than in the control group. The RLAI group needed a lower dosage of biperiden compared with the control group, even though they had similar risperidone-equivalent daily dosages.

CONCLUSION

The results of this study suggest the possibility that switching from haloperidol decanoate depot to RLAI may improve cognitive function including memory, executive function, motor processing function, and attention.

Common variants in MAGI2 gene are associated with increased risk for cognitive impairment in schizophrenic patients

Schizophrenia is a complex psychiatric disorder characterized by positive symptoms, negative symptoms, and cognitive impairment. MAGI2, a relatively large gene (∼1.5 Mbps) that maps to chromosome 7q21, is involved in recruitment of neurotransmitter receptors such as AMPA- and NMDA-type glutamate receptors. A genetic association study designed to evaluate the association between MAGI2 and cognitive performance or schizophrenia has not been conducted. In this case-control study, we examined the relationship of single nucleotide polymorphism (SNP) variations in MAGI2 and risk for schizophrenia in a large Japanese sample and explored the potential relationships between variations in MAGI2 and aspects of human cognitive function related to glutamate activity. Based on the result of first schizophrenia genome-wide association study in a Japanese population (JGWAS), we selected four independent SNPs and performed an association study using a large independent Japanese sample set (cases 1624, controls 1621). Wisconsin Card Sorting Test (WCST) was used to evaluate executive function in 114 cases and 91 controls. We found suggestive evidence for genetic association of common SNPs within MAGI2 locus and schizophrenia in Japanese population. Furthermore in terms of association between MAGI2 and cognitive performance, we observed that genotype effect of rs2190665 on WCST score was significant (p = 0.034) and rs4729938 trended toward significance (p = 0.08). In conclusion, although we could not detect strong genetic evidence for association of common variants in MAGI2 and increased schizophrenia risk in a Japanese population, these SNPs may increase risk of cognitive impairment in schizophrenic patients.

The influence of switching from oral risperidone to risperidone long-acting injection on the clinical symptoms and cognitive function in schizophrenia

OBJECTIVE

This study was a comparative investigation of the effects on clinical symptoms and cognitive function of switching schizophrenia patients from oral risperidone to risperidone long-acting injection (RLAI) compared with a control group that continued receiving oral risperidone.

METHODS

The subjects were 21 patients who had been diagnosed with schizophrenia according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Their clinical symptoms were assessed using the positive and negative syndrome scale (PANSS), and their cognitive function was assessed using the Wisconsin Card Sorting Test: Keio Version (KWCST) to assess executive function, and the St Marianna University School of Medicine's Computerized Memory Test (STM-COMET) to assess memory and concentration.

RESULTS

No significant differences in clinical symptom improvement efficacy were seen between the group that was switched to RLAI and the control group. No significant differences were seen between the two groups in the mean change from baseline in any of the KWCST tests. The mean changes from baseline on the STM-COMET memory scanning test and memory filtering test were significantly greater in the group that switched to RLAI than in the control group. Furthermore, patients with RLAI needed less biperiden, even though they had similar risperidone-equivalent daily dosages as the group with oral risperidone.

CONCLUSION

The results of this study suggested that switching from oral risperidone to RLAI may affect motor processing function and attention improvement efficacy by allowing the dosage of anti-Parkinson's medication to be reduced.

A case control association study and cognitive function analysis of neuropilin and tolloid-like 1 gene and schizophrenia in the Japanese population

Background

Using a knock-out mouse model, it was shown that NETO1 is a critical component of the NMDAR complex, and that loss of Neto1 leads to impaired hippocampal long term potentiation and hippocampal-dependent learning and memory. Moreover, hemizygosity of NETO1 was shown to be associated with autistic-like behavior in humans.

Purpose of the Research

We examined the association between schizophrenia and the neuropilin and tolloid-like 1 gene (NETO1). First, we selected eight single nucleotide polymorphisms (SNPs) within the NETO1 locus, based on the Japanese schizophrenia genome wide association study (JGWAS) results and previously conducted association studies. These SNPs were genotyped in the replication sample comprised of 963 schizophrenic patients and 919 healthy controls. We also examined the effect of associated SNPs on scores in the Continuous Performance Test and the Wisconsin Card Sorting Test Keio version (schizophrenic patients 107, healthy controls 104).

Results

There were no significant allele-wise and haplotype-wise associations in the replication analysis after Bonferroni correction. However, in meta-analysis (JGWAS and replication dataset) three association signals were observed (rs17795324: p = 0.028, rs8098760: p = 0.017, rs17086492: p = 0.003). These SNPs were followed up but we could not detect the allele-specific effect on cognitive performance measured by the Continuous performance test (CPT) and Wisconsin Card Sorting test (WCST).

Major Conclusions

We did not detect evidence for the association of NETO1 with schizophrenia in the Japanese population. Common variants within the NETO1 locus may not increase the genetic risk for schizophrenia in the Japanese population. Additionally, common variants investigated in the current study did not affect cognitive performance, as measured by the CPT and WCST.