Risperidone, negative symptoms and cognitive deficit in schizophrenia: an open study

D2/D3 dopamine receptor binding with [F-18]fallypride correlates of executive function in medication-naïve patients with schizophrenia

Converging evidence indicates that the prefrontal cortex is critically involved in executive control and that executive dysfunction is implicated in schizophrenia. Reduced dopamine D2/D3 receptor binding potential has been reported in schizophrenia, and the correlations with neuropsychological test scores have been positive and negative for different tasks. The aim of this study was to examine the relation between dopamine D2/D3 receptor levels with frontal and temporal neurocognitive performance in schizophrenia. Resting-state ¹⁸F-fallypride positron emission tomography was performed on 20 medication-naïve and 5 previously medicated for brief earlier periods patients with schizophrenia and 19 age- and sex-matched healthy volunteers. Striatal and extra-striatal dopamine D2/D3 receptor levels were quantified as binding potential using fallypride imaging. Magnetic resonance images in standard Talairach position and segmented into gray and white matter were co-registered to the fallypride images, and the AFNI stereotaxic atlas was applied. Two neuropsychological tasks known to activate frontal and temporal lobe function were chosen, specifically the Wisconsin Card Sorting Test (WCST) and the California Verbal Learning Test (CVLT). Images of the correlation coefficient between fallypride binding and WCST and CVLT performance showed a negative correlation in contrast to positive correlations in healthy volunteers. The results of this study demonstrate that lower fallypride binding potential in patients with schizophrenia may be associated with better performance. Our findings are consistent with previous studies that failed to find cognitive improvements with typical dopamine-blocking medications.

Comparison of Visuospatial and Verbal Abilities in First Psychotic Episode of Schizophrenia Spectrum Disorder: Impact on Global Functioning and Quality of Life

Objectives: Deficit in visuospatial functions can influence both simple and complex daily life activities. Despite the fact that visuospatial deficit was reported in schizophrenia, research on visuospatial functions as an independent entity is limited. Our study aims to elucidate the impact of visuospatial deficit in comparison with verbal deficit on global functioning and quality of life in the first psychotic episode of schizophrenia spectrum disorder (FES). The significance of clinical symptoms and antipsychotic medication was also studied.

Methods: Thirty-six FES patients and a matched group of healthy controls (HC group) were assessed with a neuropsychological battery focused on visuospatial (VIS) and verbal (VERB) functions. Using multiple regression analysis, we evaluated the cumulative effect of VERB and VIS functions, psychiatric symptoms (PANSS) and antipsychotic medication on global functioning (GAF) and quality of life (WHOQOL-BREF) in the FES group.

Results: The FES group demonstrated significant impairment both in VIS and VERB cognitive abilities compared to the HC group. Antipsychotic medication did not significantly affect either VIS or VERB functioning. PANSS was not related to cognitive functioning, apart from the Trail Making Test B. In the FES group, the GAF score was significantly affected by the severity of positive symptoms and VERB functioning, explaining together 60% of GAF variability. The severity of negative and positive symptoms affected only the Physical health domain of WHOQOL-BREF. The degree of VERB deficit was associated with both Physical and Psychological health. Although we did not find any relation between VIS functioning, GAF, and WHOQOL-BREF, a paradoxical finding emerged in the Environment quality domain, where a worse quality of the environment was associated with better VIS functioning.

Conclusions: Our results suggest that the deficit in VIS functions is an integral part of cognitive deficit in schizophrenia spectrum disorders, rather than a side effect of symptomatology or antipsychotic medication. Moreover, VERB functioning was a better predictor of GAF and WHOQOL-BREF than VIS functioning. Given the findings of negative or missing effect of VIS deficit on WHOQOL-BREF and GAF, the accuracy of these measures in evaluating the impact of global cognitive deficit on everyday life in schizophrenia could be questioned.

A virtual reality task based on animal research - spatial learning and memory in patients after the first episode of schizophrenia

Objectives: Cognitive deficit is considered to be a characteristic feature of schizophrenia disorder. A similar cognitive dysfunction was demonstrated in animal models of schizophrenia. However, the poor comparability of methods used to assess cognition in animals and humans could be responsible for low predictive validity of current animal models. In order to assess spatial abilities in schizophrenia and compare our results with the data obtained in animal models, we designed a virtual analog of the Morris water maze (MWM), the virtual Four Goals Navigation (vFGN) task.

Methods: Twenty-nine patients after the first psychotic episode with schizophrenia symptoms and a matched group of healthy volunteers performed the vFGN task. They were required to find and remember four hidden goal positions in an enclosed virtual arena. The task consisted of two parts. The Reference memory (RM) session with a stable goal position was designed to test spatial learning. The Delayed-matching-to-place (DMP) session presented a modified working memory protocol designed to test the ability to remember a sequence of three hidden goal positions.

Results: Data obtained in the RM session show impaired spatial learning in schizophrenia patients compared to the healthy controls in pointing and navigation accuracy. The DMP session showed impaired spatial memory in schizophrenia during the recall of spatial sequence and a similar deficit in spatial bias in the probe trials. The pointing accuracy and the quadrant preference showed higher sensitivity toward the cognitive deficit than the navigation accuracy. Direct navigation to the goal was affected by sex and age of the tested subjects. The age affected spatial performance only in healthy controls.

Conclusions: Despite some limitations of the study, our results correspond well with the previous studies in animal models of schizophrenia and support the decline of spatial cognition in schizophrenia, indicating the usefulness of the vFGN task in comparative research.

Conceptualization of the liability for schizophrenia: clinical implications

Historically, the Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnostic criteria for schizophrenia have emphasized several features, including symptoms of psychosis, a dissociation of symptoms from their etiology, a reliance on clinical symptoms, and a categorical approach to classifying the disorder. Although these emphases are quite useful, they have limitations. We review these here, and stress the importance of incorporating recent data on the genetic /biological and neurodevelopmental origins of schizophrenia into current conceptions of the disorder. We also review “schizotaxia, ” which is a concept thai embodies this point of view, occurs before the onset of psychosis, and is hypothesized to represent the liability for schizophrenia. If our hypothesis on this point is correct, the identification of schizotaxic individuals will eventually facilitate the development of prevention strategies by identifying a premorbid (but clinically significant) condition for schizophrenia. Moreover, the identification of biological or neuropsychological components of schizotaxia will provide more specific bases for developing novel treatment interventions. Our initial attempts to develop protocols for the assessment and treatment of schizotaxia are encouraging, and will be reviewed.

D(1)-like receptor activation improves PCP-induced cognitive deficits in animal models: Implications for mechanisms of improved cognitive function in schizophrenia

Phencyclidine (PCP) produces cognitive deficits of relevance to schizophrenia in animal models. The aim was to investigate the efficacy of the D(1)-like receptor agonist, SKF-38393, to improve PCP-induced deficits in the novel object recognition (NOR) and operant reversal learning (RL) tasks. Rats received either sub-chronic PCP (2 mg/kg) or vehicle for 7 days, followed by a 7-day washout. Rats were either tested in NOR or the RL tasks. In NOR, vehicle rats successfully discriminated between novel and familiar objects, an effect abolished in PCP-treated rats. SKF-38393 (6 mg/kg) significantly ameliorated the PCP-induced deficit (P<0.01) an effect significantly antagonised by SCH-23390 (0.05 mg/kg), a D(1)-like receptor antagonist (P<0.01). In the RL task sub-chronic PCP significantly reduced performance in the reversal phase (P<0.001); SKF-38393 (6.0 mg/kg) improved this PCP-induced deficit, an effect antagonised by SCH-23390 (P<0.05). These results suggest a role for D(1)-like receptors in improvement of cognitive function in paradigms of relevance to schizophrenia.

Is executive impairment associated with schizophrenic syndromes? A meta-analysis

BACKGROUND

A key neuropsychological proposal in schizophrenia is that negative and disorganization symptoms are associated with different patterns of impairment on executive tasks.

METHOD

Studies reporting correlations between positive, negative or disorganization symptoms and any type of executive test were meta-analysed. The influence of moderating factors was also examined, including age, treatment and stage of illness and whether symptoms were relapsing or persistent. The magnitudes of the correlations were compared with those for general intellectual impairment.

RESULTS

Pooled correlations between executive impairment and both negative symptoms and disorganization were significant in the small-to-moderate range. That for positive symptoms ('reality distortion'), however, was close to zero. The pattern of correlations among different executive tests differed significantly for negative symptoms and disorganization. Patients with stable clinical pictures showed significantly higher correlations with executive impairment than those with relapsing and remitting illnesses. Both negative symptoms and disorganization also correlated significantly with general intellectual function as indexed by current IQ.

CONCLUSIONS

Meta-analysis supports the view that negative symptoms and disorganization are associated with partially dissociable patterns of executive impairment. However, co-existent general intellectual impairment has been an important confounding factor in the studies to date.

Changes in neuropsychological functioning following treatment with risperidone, olanzapine, and conventional antipsychotic medications

OBJECTIVE

To compare changes in neuropsychological functioning over time among adults with schizophrenia treated with atypical and conventional antipsychotics, controlling for phenomenological changes, medication dosage, concomitant use of anticholinergic medications, and practice effects.

METHODS

In a larger clinical trial, 108 patients diagnosed with schizophrenia or schizoaffective disorder were randomly assigned to medication groups (risperidone, olanzapine, or conventional medications), treated in an open-label design, and monitored prospectively for 12 months using standard neuropsychological and symptomatology instruments.

RESULTS

Significant differential effects were evident on the ability to maintain and rapidly shift mental set within a psychomotor task, with patients in the conventional medication group consistently making more errors over time until the 12-month follow-up, when the olanzapine group made significantly more errors. Significant differential effects were also evident on delayed memory, with patients receiving olanzapine improving more steadily over time until the 12-month follow-up, when patients in the conventional group were able to recall significantly more. Positive and negative symptomatology was a significant, inversely related covariate on most of the cognitive measures examined.

CONCLUSIONS

The atypical and conventional medications examined were not consistently differential enhancers of cognitive functioning on disparate cognitive functioning measures over time.

Longitudinal studies of cognition in schizophrenia: meta-analysis

BACKGROUND

A wide range of cognitive deficits have been demonstrated in schizophrenia, but their longitudinal course remains unclear.

AIMS

To bring together all the available information from longitudinal studies of cognitive performance in people with schizophrenia.

METHOD

We carried out a meta-analysis of 53 studies. Unlike previous reviewers, we included all studies (regardless of the type of medication), analysed each variable separately and compared results with data from controls.

RESULTS

Participants with schizophrenia showed a significant improvement in most cognitive tasks. The available data for controls showed, with one exception (the Stroop test), a similar or greater improvement. Performance in semantic verbal fluency remained stable in both individuals with schizophrenia and controls.

CONCLUSIONS

Participants with schizophrenia displayed improvement in most cognitive tasks, but practice was more likely than cognitive remediation to account for most of the improvements observed. Semantic verbal fluency may be the best candidate cognitive endophenotype.

Risperidone use in children with Down syndrome, severe intellectual disability, and comorbid autistic spectrum disorders: a naturalistic study

OBJECTIVE

We report on an open-label, naturalistic study using risperidone to treat disruptive behaviors and self-injury in children with Down syndrome, severe intellectual disability, and comorbid autism spectrum disorders (DS+ASDs). We hypothesized that hyperactivity and disruptive behaviors would improve in response to risperidone treatment consistent with previous studies of children with ASD.

METHODS

Subjects were children (mean age, 7.8 +/- 2.6 years), consisting of 20 males and three females identified through our outpatient Down Syndrome Clinic between 2000 and 2004.

RESULTS

Using the Aberrant Behavior Checklist as the primary outcome measure, all five subscales showed significant improvement following risperidone treatment. The mean duration of treatment was 95.8 +/- 16.8 days, and mean total daily dose was 0.66 +/- 0.28 mg/day. The Hyperactivity, Stereotypy, and Lethargy subscale scores showed the most significant reduction (p < .001), followed by Irritability (p < .02), and Inappropriate Speech (p < .04). Children with disruptive behavior and self-injury showed the greatest improvement. Sleep quality improved for 88% of subjects with preexisting sleep disturbance. Subjects for whom a follow-up weight was available showed a mean weight increase of 2.8 +/- 1.5 kg during the treatment period.

CONCLUSIONS

These findings support our clinical impression of improvement on important target behaviors such as aggression, disruptiveness, self-injury, stereotypy, and social withdrawal. Low-dose risperidone appears to be well tolerated in children with DS+ASD, although concerns about weight gain and metabolic alterations may limit its usefulness over the long term in some children.

Neurocognitive costs and benefits of psychotropic medications in older adults

Psychotropic medications are widely used in older adults and may cause neurocognitive deficits. Older adults are at increased risk of developing adverse effects because of age-related pharmacodynamic and pharmacokinetic changes. This article provides a comprehensive review of the undesirable, and at times beneficial, effects of psychotropic medications. The review covers a wide range of medications that impair executive function, memory, and attention, as well as a much smaller group of medications that lead to improved neurocognitive function. Some of the most commonly used psychotropic medications in older adults, namely, antidepressants, sedatives, and hypnotics, are among the drugs that most consistently lead to cognitive impairments. Medications with anticholinergic properties almost invariably lead to neurocognitive dysfunction, despite symptom improvement. The neurocognitive costs and benefits of psychiatric medications should be considered in the context of disease treatment in older adults.

The effect of long-acting risperidone on working memory in schizophrenia: a functional magnetic resonance imaging study

Cognitive abnormalities represent an important therapeutic target in the treatment of schizophrenia. Working memory deficits are among the core abnormalities and affect social functioning. We used functional magnetic resonance imaging to examine cortical systems supporting working memory in patients with schizophrenia treated with risperidone long-acting injections (RLAIs) versus those on conventional depot medication (CONV). Sixteen patients on RLAI, 16 patients on CONV matched for clinical symptoms and other illness variables, and 8 HCs performed an n-back task (1-, 2-, 3-back) in the scanner. The level of performance decreased with increasing memory load, which was particularly evident in the CONV group. Patients on RLAI and controls demonstrated task-dependent decreases in activation in medial PFC, whereas the CONV group overactivated that region. The CONV group also showed underactivation of VLPFC compared with controls under conditions of increasing memory load, with the RLAI group showing an activation pattern not significantly different from either group. We conclude that RLAI may contribute to normalization of brain activation in regions involved in working memory functioning in people with chronic schizophrenia.

Effect of buspirone, a serotonin1A partial agonist, on cognitive function in schizophrenia: a randomized, double-blind, placebo-controlled study

In previous studies, we demonstrated that tandospirone, a serotonin-5-HT1A partial agonist, added to ongoing treatment with small to moderate doses of typical antipsychotic drugs, improved executive function and verbal learning and memory. However, tandospirone is not available in most countries, and atypical antipsychotic drugs (AAPDs) have largely replaced typical antipsychotic drugs as the primary treatment for schizophrenia. Therefore, the goal of this randomly assigned placebo-controlled double-blind study was to determine if the addition of buspirone, a widely available 5-HT1A partial agonist, would enhance cognitive function, in subjects with schizophrenia treated with AAPDs. Seventy-three patients with schizophrenia, who had been treated with an AAPD for at least three months, were randomly assigned to receive either buspirone, 30 mg/day, or matching placebo. All other medications remained unchanged. Attention, verbal fluency, verbal learning and memory, verbal working memory, and executive function, as well as psychopathology, were assessed at baseline, and 6 weeks, and 3 and 6 months after baseline. A significant Time x Group interaction effect was noted on the Digit Symbol Substitution Test, a measure of attention/speeded motor performance, due to better performance of the buspirone group compared to the placebo group at 3 months. No significant interaction effects were noted for other domains of cognition. Scores on the Brief Psychiatric Rating Scale (Total, Positive) were improved during treatment with buspirone but not placebo, but the effects did not reach statistical significance. The results of this study showed a possible benefit of buspirone augmentation of AAPDs to enhance attention. However, we did not replicate the results of the previous study with tandospirone, which may be due to the differences between tandospirone and buspirone, between typical antipsychotics and AAPDs, or a combination of the above. Further study to determine the usefulness of 5-HT1A agonist treatment in schizophrenia is indicated.

Pharmacological treatment of primary negative symptoms in schizophrenia: a systematic review

BACKGROUND

Optimal treatment of primary negative symptoms is important because their presence is associated with poor outcome.

AIMS

To systematically review all studies dealing with the efficacy of pharmacological agents on primary negative symptoms.

METHOD

A comprehensive search of the relevant literature was undertaken using electronic database, reference lists and personal contact.

RESULTS

There is a lack of standardized research designs. Amisulpride is the most extensively studied drug with respect to efficacy against primary negative symptoms. At low doses it demonstrates a consistent, modest effect compared to placebo, though not to conventional antipsychotics and has yet to be tested against other atypicals. Evidence from multiple studies that used simple statistical analyses and inclusion criteria for patients with primary negative symptoms does not support a direct effect for clozapine. Path-analysis studies support the direct effects of risperidone, olanzapine, sertindole and aripiprazole, however, different statistical analyses of the same risperidone study produced conflicting results and the direct effects of olanzapine were not confirmed in selected patients with primary negative symptoms. There are no studies supporting the use of ziprasidone or quetiapine. The effects of typical antipsychotics on primary negative symptoms are inconclusive and likely to depend on drug dosages. Selective serotonin reuptake inhibitors (SSRIs), mirtazepine and NMDA agonists show early promise but require further study. Novel agents such as selegiline, naltrexone, dehydroepiandrosterone, galantamine, Ginkgo, nitric oxide, L-deprenyl and pergolide show positive effects on general negative symptoms but remain untested against primary negative symptoms.

CONCLUSIONS

Further studies using standardized selective inclusion criteria and controlling for chronicity are needed. Research guidelines are discussed.

Symptom domains of schizophrenia: the role of atypical antipsychotic agents

Given their more obvious presentation, the reduction of positive symptoms and their associated behavioural problems have been considered the most important treatment outcome parameter in patients with schizophrenia. However, the development of the atypical antipsychotic agents in the early 1990s resulted in the adoption of more wide-reaching measures of therapeutic outcome. The aim of this review was to evaluate the efficacy of currently available atypical agents across multiple symptom domains of schizophrenia with a specific focus on negative symptoms, neurocognition, social functioning, quality of life and insight. As such, studies published between January 1990 and December 2005 that evaluated the clinical efficacy and tolerability of atypical antipsychotics in different symptom domains of schizophrenia were reviewed as identified from literature researches using MEDLINE and Embase. Abstracts and posters presented at key psychiatry and schizophrenia congresses during this period were also reviewed where available in the public domain. Results from the studies identified have consistently demonstrated that atypical antipsychotics have substantial advantages over conventional antipsychotics with a broader spectrum of efficacy across symptomatic domains of schizophrenia as proven by greater improvements in negative symptoms and cognitive function and a beneficial effect on affective symptoms and quality of life. However, their clinical advantages have often been limited by patients' partial compliance with therapy. As such, the development of a long-acting atypical antipsychotic agent may provide a new and valuable treatment option for patients with schizophrenia.

Antipsychotic medication and cognitive function in schizophrenia

Antipsychotic polypharmacy and excessive dosing still prevail worldwide in the treatment of schizophrenia, while their possible association with cognitive function has not well been examined. We examined whether the "non-standard" use of antipsychotics (defined as antipsychotic polypharmacy or dosage >1,000 mg/day of chlorpromazine equivalents) is associated with cognitive function. Furthermore, we compared cognitive function between patients taking only atypical antipsychotics and those taking only conventionals. Neurocognitive functions were assessed in 67 patients with chronic schizophrenia and 92 controls using the Wechsler Memory Scale-Revised (WMS-R), the Wechsler Adult Intelligence Scale-Revised (WAIS-R), the Wisconsin Card Sorting Test (WCST), and the Advanced Trail Making Test (ATMT). Patients showed markedly poorer performance than controls on all these tests. Patients on non-standard antipsychotic medication demonstrated poorer performance than those on standard medication on visual memory, delayed recall, performance IQ, and executive function. Patients taking atypical antipsychotics showed better performance than those taking conventionals on visual memory, delayed recall, and executive function. Clinical characteristics such as duration of medication, number of hospitalizations, and concomitant antiparkinsonian drugs were different between the treatment groups (both dichotomies of standard/non-standard and conventional/atypical). These results provide evidence for an association between antipsychotic medication and cognitive function. This association between antipsychotic medication and cognitive function may be due to differential illness severity (e.g., non-standard treatment for severely ill patients who have severe cognitive impairment). Alternatively, poorer cognitive function may be due in part to polypharmacy or excessive dosing. Further investigations are required to draw any conclusions.

The neurocognitive effects of aripiprazole: an open-label comparison with olanzapine

RATIONALE

Cognitive deficits are a core feature of schizophrenia. As a target of intervention, improvements in cognition may lead to improvements in functional outcome.

OBJECTIVES

The present paper is the first report, to our knowledge, on the neurocognitive effects of aripiprazole. Unlike other second-generation antipsychotics, aripiprazole is a D(2) and D(3) receptor partial agonist. It is unknown what effects this unusual pharmacological profile may yield on neurocognition.

MATERIALS AND METHODS

The present open-label study included data on 169 patients with schizophrenia or schizoaffective disorder who were randomly treated with aripiprazole or olanzapine. Subjects received a neurocognitive battery at baseline, week 8, and 26.

RESULTS

The aripiprazole group had a significantly greater dropout rate than the olanzapine group. Neurocognitive data were reduced through a principal components analysis that yielded a three-factor solution. The factors were general cognitive functioning, executive functioning, and verbal learning. For general cognitive functioning, both groups improved from baseline and the effects were relatively stable over the 26-week protocol. There were no differential treatment effects. For executive functioning, neither group improved significantly from baseline. For verbal learning, the aripiprazole group improved significantly from baseline to the 8th and 26th week of assessment, and there was a between-group effect favoring aripiprazole over olanzapine that was largely attributable to the differences in performance within the 8th week. Separate analyses were conducted for a measure of sustained attention (Continuous Performance Test-Identical Pairs). There were no differential treatment effects on this measure.

CONCLUSIONS

The findings from this open-label study suggest that the neurocognitive effects of aripiprazole are at least as good as those of olanzapine.

Measuring memory impairment in community-based patients with schizophrenia. Case-control study

BACKGROUND

The majority of memory impairment studies in schizophrenia are cohort studies using laboratory-based tests, which make it difficult to estimate the true extent and relevance of memory impairment in patients with schizophrenia in the community.

AIMS

To examine the extent of memory impairment in community-based patients with schizophrenia using a clinically relevant test.

METHOD

All patients with schizophrenia (n=190) in one catchment area were identified, of whom 133 were potentially eligible for the study; 73 patients volunteered to take part. They were assessed using the Rivermead Behavioural Memory Test (RBMT), the National Adult Reading Test, the Positive and Negative Syndrome Scale, the Health of the Nation Outcome Scales and the Scales and the Office for National Statistics Classification of Occupation. Their performance on the memory test was compared with that of matched controls (n=71).

RESULTS

Patients as a group performed significantly worse (P<0.001) than controls on the RBMT. Using the RBMT normative scores, 81% of patients were found to have impaired memory compared with 28% of controls.

CONCLUSIONS

Using a clinically relevant test, the majority of community-based patients with schizophrenia may have memory impairment.

Perospirone in the treatment of schizophrenia: effect on verbal memory organization

The present study was performed to determine if perospirone, a novel antipsychotic drug with D2/5-HT2A antagonist and partial 5-HT1A agonist properties, would improve memory organization in twelve patients with chronic schizophrenia. Switching to equivalent dose of perospirone from prior antipsychotic medication was associated with a significant improvement in indices of verbal memory organization of the Auditory Verbal Learning Test. Negative symptoms and extrapyramidal side effects were also ameliorated after switching to perospirone. The distinct cognitive enhancement profile of perospirone may be attributable to its partial 5-HT1A agonist action.

One-year double-blind study of the neurocognitive efficacy of olanzapine, risperidone, and haloperidol in schizophrenia

Neurocognitive deficits in schizophrenia can reach 1 to 2 standard deviations below healthy controls. The comparative effect of typical and atypical antipsychotic medications on neurocognition is controversial, and based primarily on studies with small samples and large doses of typical comparator medications. The present study assessed neurocognitive efficacy. It was hypothesized that olanzapine treatment would improve neurocognitive deficits to a greater degree than either risperidone or haloperidol treatment. This was a double-blind, randomized, controlled, parallel study with neurocognition assessed at baseline, and 8, 24, and 52 weeks. Per protocol, the haloperidol arm was discontinued. Four hundred and fourteen inpatients or outpatients with schizophrenia and schizoaffective disorder were treated with oral olanzapine (n = 159), risperidone (n = 158), or haloperidol (n = 97). Individual domains (executive function, learning and memory, processing speed, attention/vigilance, verbal working memory, verbal fluency, motor function, and visuospatial ability) were transformed into composite scores and compared between treatment groups. At the 52-week endpoint, neurocognition significantly improved in each group (p < 0.01 for olanzapine and risperidone, p = 0.04 for haloperidol), with no significant differences between groups. Olanzapine- and risperidone-treated patients significantly (p < 0.05) improved on domains of executive function, learning/memory, processing speed, attention/vigilance, verbal working memory, and motor functions. Additionally, risperidone-treated patients improved on domains of visuospatial memory. Haloperidol-treated patients improved only on domains of learning/memory. However, patients able to remain in treatment for the entire 52 weeks benefited more from olanzapine or risperidone treatment than haloperidol treatment.

The effect of neuroleptic treatments on executive function and symptomatology in schizophrenia: a 1-year follow up study

Cognitive dysfunctions (as in memory, attention and executive function) have been recognized as fundamental features of schizophrenia. Executive dysfunction is a major obstacle to functional outcome, community functioning and rehabilitation success and it is crucial to assess the effects of so-called neuroleptic (NLP) medications in this domain of cognitive functioning. Risperidone, an atypical NLP, has been reported to improve executive function in schizophrenia (SZ), but there is controversy regarding these findings. The aim of the current study was to assess the differential effects of risperidone (2-6 mg) and conventional (2-40 mg haloperidol) NLPs on executive skills in 31 individuals with SZ over a 12-month period. The performance of both NLP groups was compared to the performance of 17 age- and education-matched healthy controls. In this randomized, double blind study, the Wisconsin Card Sorting Test (WCST) was administered at baseline, 3, 6, and 12 months after initiating medication. The relationship between executive functioning and the course of clinical symptoms, as assessed by the Positive and Negative Syndrome Scale (PANSS) was also investigated. Results showed that, relative to healthy controls, individuals with SZ showed marked impairment in WCST from baseline through 12 months of treatment. Also, participants under haloperidol or risperidone NLP medication performed similarly on the WCST at all assessment periods showing that risperidone and haloperidol do not differ in their effect on executive functioning. Risperidone treatment, however, was more effective in the reduction of negative symptoms. The differential efficacy of risperidone over negative symptoms and WCST performance strongly suggests that the executive impairments are to some extent the result of brain abnormalities independent of those that produce the major psychopathology manifestations seen in SZ.

Neural correlates of adjunctive rivastigmine treatment to antipsychotics in schizophrenia: a randomized, placebo-controlled, double-blind fMRI study

Facilitation of central cholinergic activity may form a potential treatment strategy for cognitive impairment in schizophrenia. In a randomized, placebo-controlled, double-blind, parallel-group design, we investigated the neural correlates of cognitive effects of rivastigmine, an acetylcholinesterase inhibitor, given as an add-on therapy to antipsychotic-treated schizophrenia patients. Thirty-six chronic schizophrenia patients with mild cognitive impairment took part. After 1 week on placebo (baseline), all patients entered a double-blind protocol; 18 were allocated to receive rivastigmine and 18 placebo for the next 12 weeks (final sample with usable imaging data: 11 patients on rivastigmine, 10 on placebo). All patients underwent functional magnetic resonance imaging during a parametric 'n-back' task, involving monitoring of dots in particular locations on a screen at a given delay from the original occurrence, twice: at baseline and 12 weeks post-rivastigmine/placebo treatment. Compared to placebo, rivastigmine produced only a small and non-significant improvement in task accuracy across all conditions with no change in response latency, and increased activity in the extrastriate visual cortex in areas associated with visual and spatial attention but not in any region within the working memory network. Our observations suggest that cholinergic enhancement with rivastigmine at doses known to be effective in Alzheimer's disease does not produce strong and clinically meaningful cognitive and neural changes in schizophrenia patients treated with atypical antipsychotics although the neural effects in terms of enhanced neuronal activity in regions associated with visual and spatial attention are consistent with those reported previously with cholinergic enhancement in healthy subjects.

Current therapy issues and unmet clinical needs in the treatment of schizophrenia: a review of the new generation antipsychotics

This review discusses the atypical antipsychotics, focusing on the possibility of symptom reduction with a minimum of side-effects. A selective review of clinically relevant reports, studies and meta-analyses is presented. The results from clinical trials suggest that atypical agents improve negative and affective symptoms, and cognitive functioning more than typical antipsychotics, but that the pattern of effects on these domains, as well as on suicidality, appears to differ. In clinical trials, the newer drugs generally have less extrapyramidal side-effects (EPS) than typical antipsychotics. However, amisulpride, risperidone, olanzapine and ziprasidone still show evidence of a dose-related increase in EPS, whereas clozapine, quetiapine, sertindole and aripiprazole do not. Weight gain, increased blood lipids/cholesterol, and insulin resistance/type 2 diabetes are emerging as significant treatment-associated concerns, particularly for clozapine and olanzapine. Sedation has been reported for all the newer compounds except sertindole. The considerable variation in benefit/risk profiles of the atypical compounds can help the clinician to select the most appropriate treatment for individual patients.

Prediction of response to risperidone treatment with respect to plasma concencentrations of risperidone, catecholamine metabolites, and polymorphism of cytochrome P450 2D6

In the present study, we examined the relationships between plasma concentrations of risperidone and clinical responses, extrapyramidal symptoms, plasma levels of cotinine and caffeine, or cytochrome (cyp)2D6 genotypes. In addition, we also investigated the relationships between plasma levels of 3-methoxy-4-hydroxyphenylglycol (MHPG) or homovanillic (HVA) acid and clinical responses to risperidone. One hundred and 36 patients (male/female: 58/78, age 37+/-13 years) who met DSM-IV criteria for schizophrenia, schizoaffective disorder, delusional disorder and brief psychotic disorder, and who were being treated with risperidone alone, were evaluated regarding their clinical improvement and extrapyramidal symptoms using the Positive and Negative Syndrome Scale (PANSS) and Simpson and Angus (SAS), respectively, and plasma levels of cotinine, caffeine, MHPG and HVA were analysed by high-performance liquid chromatography. The cyp2D6*5 and *10 alleles were identified using the polymerase chain reaction. There was a positive correlation between plasma levels of risperidone plus 9-hydroxyrisperidone (active moiety) and SAS scores, but not the PANSS. Pretreatment HVA levels in responders were higher than those in nonresponders. In addition, there was a negative correlation between changes in HVA levels and improvement in PANSS scores. There was no association between plasma levels of risperidone and plasma levels of cotinine or caffeine. Furthermore, there were no differences in the risperidone/9-hydroxyrisperidone ratio, clinical improvements and extrapyramidal symptoms among cyp2D6 genotypes. These results indicate that pretreatment HVA levels and plasma concentrations of active moiety might play a part in predicting the clinical response and occurrence of extrapyramidal symptoms, respectively, when treating patients with risperidone.

On the trail of a cognitive enhancer for the treatment of schizophrenia

The aim of this critical review is to address that the study of cognition and antipsychotics is not always driven by logic and that research into real pro-cognitive drug treatments must be guided by a better understanding of the biochemical mechanisms underlying cognitive processes and deficits. Many studies have established that typical neuroleptic drugs do not improve cognitive impairment. Atypical antipsychotics improve cognition, but the pattern of improvement differs from drug to drug. Diminished cholinergic activity has been associated with memory impairments. Why atypical drugs improve aspects of cognition might lie in their ability to increase dopamine and acetylcholine in the prefrontal cortex. An optimum amount of dopamine activity in the prefrontal cortex is critical for cognitive functioning. Another mechanism is related to procedural learning, and would explain the quality of the practice during repeated evaluations with atypical antipsychotics due to a more balanced blockage of D2 receptors. Laboratory studies have shown that clozapine, ziprasidone, olanzapine, and risperidone all selectively increase acetylcholine release in the prefrontal cortex, whereas this is not true for haloperidol and thioridazine. A few studies have suggested that cholinomimetics or AChE inhibitors can improve memory functions not only in Alzheimer's disease but also in other pathologies. Some studies support the role of decreased cholinergic activity in the cognitive deficits while others demonstrate that decreased choline acetyltransferase activity is related to deterioration in cognitive performance in schizophrenia. Overall, results suggest the hypothesis that the cholinergic system is involved in the cognitive dysfunctions observed in schizophrenia and that increased cholinergic activity may improve these impairments. Furthermore, a dysfunction of glutamatergic neurotransmission could play a key role in cognitive deficits associated with schizophrenia. Further meta-analysis of various clinical trials in this field is required to account for matters on the grounds of evidence-based medicine.

Effects of haloperidol and risperidone on psychomotor performance relevant to driving ability in schizophrenic patients compared to healthy controls

The effects of antipsychotic treatment on the psychomotor performance and driving ability of schizophrenic patients is subject of investigation. The present study was designed to evaluate the effects of an atypical neuroleptic (risperidone) in comparison to a conventional dopamine antagonist neuroleptic (haloperidol) on several dimensions of psychomotor performance (visual perception, attention, reaction time, and sensorimotor performance) considered to be of relevance in evaluating driving fitness. Psychomotor performance was assessed by means of the ART 90 (act-and-react test), a computerized test battery which is frequently used in diagnosis of psychomotor performance. The 40 participating patients were examined at discharge following psychopathological stabilisation; 20 received haloperidol medication, 20 received the atypical neuroleptic risperidone. Nineteen healthy individuals were studied as a control group. Our findings indicate a remarkably reduced psychomotor performance in both groups of schizophrenic patients compared to healthy controls. We did find a significant but low correlation between age and some items of the RST3 and between age and the tracking performance on the PVT. The younger patients showed a better test performance than older patients. The BPRS-score was significantly correlated with only two items of the RST3. However, patients under treatment with risperidone showed significantly better results compared to patients treated with haloperidol. Only one (5%) subject passed all subtests without major failures and could be regarded as competent to drive. Among patients with risperidone, seven patients (35%) passed all test parameters without major failures. Clinical implications of these findings are discussed.

Cognitive functioning in young people with first episode psychosis: relationship to diagnosis and clinical characteristics

OBJECTIVE

To examine the extent and nature of neuropsychological deficits in adolescents and young people with first episode psychosis (FEP), and to determine whether the pattern and extent of neuropsychological deficits varied according to diagnosis.

METHOD

A total of 83 FEP subjects aged 13-25 years, and 31 healthy controls completed a comprehensive battery of neuropsychological tests, grouped into 10 cognitive domains. First episode psychosis subjects were stratified into three diagnostic groups (schizophrenia, affective disorders, substance-induced psychosis) and differences in cognitive profiles were examined. The contribution of demographic and clinical characteristics to cognitive performance was also explored.

RESULTS

The schizophrenia group demonstrated significantly worse performance on tasks of verbal learning and memory than the affective disorders group. Compared to healthy controls, the schizophrenia group also demonstrated global impairment across the majority of cognitive domains. The substance-induced group's performance lay between that of the schizophrenia and affective disorders groups. Analyses of differential deficits revealed that verbal learning, verbal memory and current intellectual functioning were selectively impaired in the schizophrenia group, whereas the affective disorders group demonstrated a selective deficit in speeded processing. Premorbid intellectual functioning, negative symptomatology and medication levels were the strongest predictors of cognitive performance in FEP subjects.

CONCLUSIONS

Verbal memory deficits differentiate individuals with schizophrenia from those with psychotic affective disorders. Although significant cognitive deficits are evident across all diagnostic FEP groups, individuals with schizophrenia appear to have more generalized impairment across a broad array of cognitive functions than other psychotic diagnoses. Lower premorbid intellectual functioning does not appear to contribute to greater cognitive deterioration following onset of psychosis, but severity of illness may be a more important factor than levels of mood disturbance.

Effects of amisulpride, risperidone and chlorpromazine on auditory and visual latent inhibition, prepulse inhibition, executive function and eye movements in healthy volunteers

In view of the evidence that cognitive deficits in schizophrenia are critically important for long-term outcome, it is essential to establish the effects that the various antipsychotic compounds have on cognition, particularly second-generation drugs. This parallel group, placebo-controlled study aimed to compare the effects in healthy volunteers (n = 128) of acute doses of the atypical antipsychotics amisulpride (300 mg) and risperidone (3 mg) to those of chlorpromazine (100 mg) on tests thought relevant to the schizophrenic process: auditory and visual latent inhibition, prepulse inhibition of the acoustic startle response, executive function and eye movements. The drugs tested were not found to affect auditory latent inhibition, prepulse inhibition or executive functioning as measured by the Cambridge Neuropsychological Test Battery and the FAS test of verbal fluency. However, risperidone disrupted and amisulpride showed a trend to disrupt visual latent inhibition. Although amisulpride did not affect eye movements, both risperidone and chlorpromazine decreased peak saccadic velocity and increased antisaccade error rates, which, in the risperidone group, correlated with drug-induced akathisia. It was concluded that single doses of these drugs appear to have little effect on cognition, but may affect eye movement parameters in accordance with the amount of sedation and akathisia they produce. The effect risperidone had on latent inhibition is likely to relate to its serotonergic properties. Furthermore, as the trend for disrupted visual latent inhibition following amisulpride was similar in nature to that which would be expected with amphetamine, it was concluded that its behaviour in this model is consistent with its preferential presynaptic dopamine antagonistic activity in low dose and its efficacy in the negative symptoms of schizophrenia.

Clinical potential of omega-3 fatty acids in the treatment of schizophrenia

The phospholipids in the neuronal membranes of the brain are rich in highly unsaturated essential fatty acids (EFAs). It has been hypothesised that abnormalities of phospholipid metabolism are present in patients with schizophrenia and that the EFAs omega-3 polyunsaturated fatty acids, and eicosapentaenoic acid (EPA) in particular, may have a role in treating this illness. Considerable preclinical and clinical evidence provides support for this proposal. An epidemiological study reported a better outcome for patients with schizophrenia in countries where the diet is rich in unsaturated fatty acids. Evidence of abnormalities of EFAs has been found in erythrocyte membranes and cultured skin fibroblasts of patients with schizophrenia, and abnormal retinal function and niacin skin flush tests (markers of omega-3 polyunsaturated fatty acid depletion) have also been reported. Case reports and an open-label clinical trial reported efficacy for EPA in schizophrenia. Four randomised, controlled trials of EPA versus placebo as supplemental medication have now been reported. Two of these trials showed significant benefit with EPA on the positive and negative symptom scale total scores, whereas the other two did not show any effects on this primary efficacy measure. One study also reported a beneficial effect on dyskinesia. In the only published trial in which EPA was used as monotherapy versus placebo in schizophrenia, some evidence was found to suggest antipsychotic activity. Taken together, there is considerable evidence to suggest abnormalities of EFAs in cell membranes of patients with schizophrenia, and there is preliminary evidence that EPA is an effective adjunct to antipsychotics.

Different effects of five dopamine receptor subtypes on nuclear factor-kappaB activity in NG108-15 cells and mouse brain

We previously showed that dopamine receptors D1R and D2R expressed in NG108-15 cells activated protein kinase A and extracellular signal-regulated kinase (ERK) respectively, resulting in differential activation of nuclear factor (NF)-kappaB activity. To investigate whether other dopamine receptor subtypes regulate NF-kappaB, we established NG108-15 cells stably expressing D3R, D4R and D5R (NGD3R, NGD4R and NGD5R). D5R stimulation with SKF 38393 decreased NF-kappaB luciferase reporter activity in NGD5R cells, similar to D1R stimulation in NGD1R cells. However, D3R or D4R stimulation with quinpirole showed no change in NF-kappaB-Luci activity, although forskolin-induced cyclic AMP responsive element-Luci activation was attenuated by quinpirole treatment in NGD2LR, NGD3R and NGD4R cells. As expected, activation of ERK or serum responsive element-luciferase reporter not observed following stimulation with quinpirole in D3R- or D4R-expressing cells. We further examined the effects of haloperidol and risperidone, which are typical and atypical antipsychotic drugs respectively, on NF-kappaB activity by gel shift assay in mouse frontal cortex. Haloperidol treatment slightly attenuated basal NF-kappaB activity. By contrast, risperidone treatment enhanced NF-kappaB activity. Taken together, D2R and D1R/D5R had opposite effects on NF-kappaB activity in NG108-15 cells. Risperidone up-regulated and haloperidol down-regulated NF-kappaB activity in mouse brain. This effect may be related to the atypical antipsychotic properties of risperidone.

Comparative effects of risperidone and olanzapine on cognition in elderly patients with schizophrenia or schizoaffective disorder

OBJECTIVE

To examine the effects of risperidone and olanzapine on cognitive functioning in elderly patients with schizophrenia or schizoaffective disorder.

METHOD

One hundred seventy-six elderly inpatients and outpatients with schizophrenia or schizoaffective disorder were enrolled in this multicenter, double-blind trial. After their antipsychotic medications were tapered for 1 week, patients were randomly assigned to receive either risperidone 1 to 3 mg/day or olanzapine 5 to 20 mg/day for 8 weeks. Performance on the Continuous Performance Test (CPT), Serial Verbal Learning Test (SVLT), TMT (Trail Making Test) Parts A and B, Wisconsin Card Sorting Test (WCST), and Verbal Fluency Examinations (VFE) was assessed at baseline and at end point.

RESULTS

Patients in the risperidone group had improved scores on at least one test of attention, memory, executive function, and verbal fluency, and those in the olanzapine group had improved scores on at least one test of attention and memory function. Scores on the TMT Part B, WCST total errors (executive function domain), and the VFE improved significantly from baseline in the risperidone group but not in the olanzapine group. No significant differences in change scores between the two groups were found. Higher baseline scores on each test predicted more improvement at endpoint.

CONCLUSIONS

Low doses of risperidone and olanzapine improve cognitive function in elderly patients with schizophrenia or schizoaffective disorder. Consistent with research in younger populations, these improvements occur in aspects of cognitive functioning related to functional outcome.

Future employability, a new approach to cost-effectiveness analysis of antipsychotic therapy

OBJECTIVE

Schizophrenia patients pose a substantial burden in terms of indirect costs, much of which is attributable to loss of employment. We present a new approach to assess the cost-effectiveness (CE) of risperidone vs. haloperidol using employability as an outcome measure.

METHODS

A decision analytic CE model was developed to compare the two treatments over a 1-year period including all direct medical costs and the number of employable persons as a measure of effectiveness. A measure of executive functioning, the Wisconsin Card Sorting Test Category score (WCST-Cat score), was used as an intermediate endpoint from which employability was modeled. A Monte Carlo procedure, using WCST-Cat score sampling distributions from clinical trials, simulated the WCST-Cat score distribution for a cohort of 10,000 patients. A clinically stable patient, with a Positive and Negative Syndrome Scale (PANSS) score increase of at least 20% and a WCST-Cat score of > or =3.5 was assumed to be employable. Sensitivity analysis was performed for key values.

RESULTS

The base case per-patient cost of risperidone and haloperidol was 6,422 US dollars and 4,989 US dollars, respectively, and the number of employable persons was 3,258 (32.58%) and 2,517 (25.17%), respectively, which translates to an incremental CE ratio of 19,609 US dollars per employable person for risperidone. Risperidone remained cost increasing and had higher number of employable persons over all the ranges used in the sensitivity analysis. The incremental CE ratio ranged from a high of 1,000,000 US dollars to a low of 3,000 US dollars per employable persons when the rates of clinical stability for risperidone and haloperidol therapy were varied.

CONCLUSION

Gains from earning rates for employed persons with schizophrenia, savings in informal caregiver costs and other human benefits could justify an incremental cost of 19,609 US dollars for each additional employable person prescribed risperidone.

Comparison of cognitive performances during a placebo period and an atypical antipsychotic treatment period in schizophrenia: critical examination of confounds

Although previous studies report cognitive improvement following atypical antipsychotic administration in schizophrenia (SC), few placebo-controlled within-subject studies with examination of confounds (symptom reduction, cooperation, learning, and outliers) have been reported. The present study examines the effects of atypicals and confounds upon cognition in SC. The hypothesis tested was that relative to placebo, atypicals as a general class of medication would elicit cognitive improvement in SC. In all, 19 patients with SC (15 males) completed the double-blind, counterbalanced, randomized within-subject study of the effects of atypical antipsychotics (risperidone, clozapine, olanzapine, or quetiapine) vs placebo administration upon cognitive performance in the domains of executive function, attention, memory, language, visual perception, and general intellect. Significant cognitive improvement during atypical antipsychotic administration relative to placebo withdrawal occurred in most cognitive domains with robust improvements in intelligence (p=0.001), memory (p=0.0009), and fluency (p <0.002) even after outliers and unmotivated performances were excluded. These findings suggest that relative to placebo withdrawal, atypicals improve cognitive performance in SC. However, this finding may not be specific to atypicals, since analogous studies of typicals have not been performed.

Plasma levels of homovanillic acid and the response to risperidone in first episode untreated acute schizophrenia

We have previously reported that risperidone might improve negative symptoms in schizophrenia by influencing noradrenergic neurons. In the present study, we focused on the clinical efficacy and mechanisms of risperidone towards positive symptoms in the acute phase of schizophrenia. Thirty-four patients meeting DSM-IV criteria for schizophrenia and treated with risperidone alone were evaluated regarding their clinical improvement using the Positive and Negative Syndrome Scale (PANSS) before and 2 weeks after risperidone administration, and blood samples were also drawn at the same times. Plasma concentrations of homovanillic acid (HVA) and 3-methoxy-4-hydroxyphenylglycol were analysed by high-performance liquid chromatography with electrochemical detection. Plasma HVA levels in the responders to the risperidone treatment (more than 50% improvement in scores of positive symptoms in PANSS) were higher than those of non-responders before risperidone administration. Furthermore, there was a negative trend between changes in plasma HVA levels and improvement of total scores for positive symptoms in PANSS. These results suggest that higher levels of plasma HVA before risperidone administration might be a predictor of a good response to risperidone treatment, and the influence of risperidone on dopaminergic activity might be associated with its efficacy in treating symptoms of schizophrenia in the acute phase.

The effect of melperone, an atypical antipsychotic drug, on cognitive function in schizophrenia

Melperone, a butyrophenone, has been shown to possess atypical antipsychotic properties, i.e. ability to produce an antipsychotic effect in man at doses that cause minimal extrapyramidal side effects. In addition, melperone shares the following with other atypical antipsychotic drugs: (1) effectiveness for ameliorating negative symptoms; (2) no prolactin elevation; and (3) effectiveness in the treatment of some patients with neuroleptic-resistant schizophrenia. Other atypical antipsychotic drugs have been reported to improve cognitive function. This study was performed to investigate the effect of melperone on cognitive function. Nineteen patients with schizophrenia or schizoaffective disorder, including 11 neuroleptic-resistant patients, were treated with melperone for 6 weeks. A comprehensive neurocognitive test battery and psychopathological ratings (Brief Psychiatric Rating Scale, BPRS) were administered at baseline and after 6 weeks of melperone treatment. Treatment with melperone was associated with improvement in executive function, as measured by the Wisconsin Card Sorting Test (WCST)-Categories and WCST-Percent Perseveration. On the other hand, visuospatial manipulation, as measured by the Wechsler Intelligent Scale for Children-Revised (WISC-R) Maze, worsened during melperone treatment. There were no significant changes in other domains of cognition, i.e. verbal learning and memory, verbal working memory, verbal fluency and sustained attention. Scores of WCST-Categories and Perseveration at 6 weeks were predicted from the relevant cognitive test scores at baseline and the change in BPRS Total and Positive scores. These results suggest the usefulness of melperone for facilitating work and social function in patients with schizophrenia. The differences in the cognition-enhancing abilities between melperone and clozapine are discussed.

Cognitive effects and antipsychotic treatment

Cognitive impairment has long been recognized as central to the abnormalities that occur in schizophrenia, since neurocognitive deficits are predictive of a number of outcome indices, and they pose a significant obstacle to any attempts at social rehabilitation. This raises the possibility that treatments producing improvements in cognitive function might, in turn, prove to have synergistic effects with psychosocial interventions. Rather than improving cognitive deficits, conventional antipsychotics may instead contribute to the impairment seen in many patients with schizophrenia. These damaging effects on cognition might be expected not only when antipsychotic drugs with intrinsic anticholinergic properties are used but also when anticholinergic drugs are prescribed for the relief of treatment-emergent extrapyramidal symptoms. The atypical antipsychotic drugs may be effective in this area, either in amelioration of the cognitive impairments that occur in schizophrenia or in arresting any continuing decline. New-generation atypical agents, such as quetiapine and risperidone, have minimal intrinsic anticholinergic effects, which suggest that some of the additional negative effects on cognition can be avoided. A number of large-scale, long-term follow-up studies of atypical antipsychotics are currently underway, in 'real world' settings, to assess not only control of symptoms of schizophrenia but also improvement in social, occupational, and inter-personal functioning.

Costs and outcomes of risperidone treatment in schizophrenia in the Czech Republic

The increasing cost of pharmaceuticals in the Czech Republic has led to restrictions on the prescription of more expensive atypical antipsychotics. The aim of the study was to compare the costs and outcomes of using risperidone versus classical neuroleptics in treatment of schizophrenia in order to see if there was any cost advantage in restricting use of more recent antipsychotics. Sixty-seven patients (39 women) with a mean age of 34.6 years (S.D. = 9.74) suffering from schizophrenia or schizoaffective disorder were treated with risperidone while 67 patients (39 women) with the same diagnoses with a mean age of 35.7 years (S.D. = 9.91) received standard neuroleptics. Yearly direct medical costs and outcomes (indicated by the average Global Assessment of Functioning score) were assessed retrospectively in an open, intent-to-treat study by abstracting psychiatric outpatient charts. The outcomes were not significantly different between the treatment groups while the risperidone treatment was significantly more expensive than the therapy with standard neuroleptics. This result which appears to be inconsistent with the literature was caused by the cheap labor force in the Czech Republic. The difference between the followed treatments in the direct costs will probably become insignificant in the future when the country's economy will be more developed.

Long-term pharmacoclinical follow-up in schizophrenic patients treated with risperidone. Plasma and red blood cell concentrations of risperidone and its 9-hydroxymetabolite and their relationship to whole blood serotonin and tryptophan, plasma homovanillic acid, 5-hydroxyindoleacetic acid, dihydroxyphenylethyleneglycol and clinical evaluations

The aim of the study was to establish a relationship between the clinical efficacy of risperidone (Risp), the biological levels of Risp and its metabolite, 9-hydroxyrisperidone (9-OH-Risp), and the turnover of blood biogenic amines during a long-term treatment (1 year). Risp is one of the newer atypical antipsychotic drugs with potent serotonin (5HT2), moderate D2 and real alpha 1-alpha 2 adrenoreceptor antagonistic effects. The study has been performed in an open setting and included 17 patients, but only 15 were followed-up from 3 to 12 months. Pharmacokinetic analyses were conducted at the same time as clinical evaluations, grading using the Positive and Negative Syndrome Scale (PANSS), the Clinical Global Impressions (CGI), the Global Assessment of Functioning Scale (GAF), the Quality of Life Scale (QLS) and the Extrapyramidal Symptoms Rating Scale (ESRS) and the determinations of plasma and red blood cell (RBC) Risp and 9-OH-Risp, whole blood 5HT and tryptophan (Trp), plasma homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5HIAA) and dihydroxyphenylethyleneglycol (DHPG). The therapeutic drug monitoring needed oral Risp daily dose of 4.5 +/- 2.3 mg (range 2-8) and the stabilized concentrations (ng/ml) at endpoint in plasma and RBC were 10 +/- 8 (range 1-23) and 3.5 +/- 2 (range 1-8) for Risp and 29 +/- 19 (range 8-70) and 11.5 +/- 6.6 (range 2.6-22.5) for 9-OH-Risp, respectively. 9-OH-Risp appears to be the major active metabolite compound at higher concentrations than Risp. Positive linear correlations were found only between plasma and RBC 9-OH-Risp and the daily dose and the score of the GAF. Statistically significant clinical results showed that Risp is a potent antipsychotic agent efficacious both on positive and negative symptoms and on quality of life. Positive symptoms decreased after about the second month and the negative symptoms improved secondly. Patients (n = 8) who responded to Risp were characterized, on the long-term, by a statistically significant decrease of whole blood 5HT and increase of plasma DHPG.

Executive control function in psychiatric and medical illness

Executive Control Function (ECF) is the ability to plan, sequence, and monitor one's behavior in order to accomplish a given goal while simultaneously exercising cognitive flexibility to adapt to changing task requirements. Multiple studies demonstrate that ECF predicts functional outcome, level of care required, and work potential for both well and ill populations. However, clinicians often do not routinely assess ECF during mental status evaluations because of the perceived lack of practical bedside tests. This review article discusses the major neuropsychological measures used to probe for impairment, with special emphasis on those that are easily administered at the patient's bedside. The current literature on executive dysfunction in psychiatric and medical illness is reviewed. The neuroanatomy and neurochemistry of ECF is also reviewed, with emphasis on structural dysfunction in specific illnesses. Finally, various treatment options, both pharmacological and psychotherapeutic, are discussed.

Improved antisaccade performance with risperidone in schizophrenia

OBJECTIVE

Antisaccade errors are consistently increased in schizophrenia. As they have been demonstrated only in cross sectional studies, it is unclear how they vary longitudinally or with different medications. In a previous cross sectional study, we reported a trend towards a reduction in error rates in a patient group treated with risperidone, compared with clozapine and sulpiride treated groups.

METHODS

Gap random and antisaccade paradigms were performed on two occasions in the same sample of DSM-IV schizophrenic patients (n=12) in transition between conventional antipsychotic drugs and risperidone. A cross over design was used with six patients switching from risperidone to conventional (group I) and six in the opposite direction (group II). A control sample (n=12) was also tested on two occasions and their performance compared. The effects of practice between first and second testing and of switching between conventional antipsychotic drugs and risperidone and vice versa was also evaluated.

RESULTS

A significant reduction in error rate was demonstrated during risperidone treatment (n=12), compared with conventional APD treatment. Switching from conventional to risperidone produced a reduction in errors, and vice versa.

CONCLUSIONS

Treatment with risperidone was associated with improvement in antisaccade errors.

Effects of risperidone on information processing and attention in first-episode schizophrenia

Risperidone appears to have a beneficial effect in several areas of cognitive function in schizophrenic patients. In previous studies, however, the clinical characteristics of the subjects differed between studies, and were heterogeneous even in single study. Most of the subjects were previously exposed to different kinds of neuroleptics and some of them were treatment-resistant. The aim of this study is to evaluate the effect of risperidone on attention and information processing in a homogeneous subgroup of schizophrenic patients, i.e. drug-naïve first-episode inpatients. In the patient group (n=17), cognitive tests and clinical assessments were performed before and after 8 weeks of risperidone treatment. The same cognitive tests were administered to the control group (n=24). The delay between test and retest was 8 weeks. Before treatment, the patient group performed significantly worse than control group on the tests measuring continuous attention, vigilance, and the speed of information processing. After treatment (the average dose of risperidone was 7.3mg/day), in spite of significant improvement of the clinical symptoms, the patients did not show any significant improvement or worsening in most of the items of these tests. The control group did not show any practice effect. These results suggest that first-episode schizophrenic patients have deficits in sustained attention and vigilance to visual stimuli, as well as the speed of information processing to visual and auditory stimuli, and these deficits are unrelated to clinical symptoms and remain stable during the early phase of treatment. This study did not receive pharmaceutical company financial support.

The effect of tandospirone, a serotonin(1A) agonist, on memory function in schizophrenia

BACKGROUND

The purpose of this study was to test the hypothesis that the addition of tandospirone, a 5-HT(1A) partial agonist, to ongoing treatment with typical antipsychotic drugs, would improve memory function in patients with schizophrenia.

METHODS

Eleven outpatients (male/female = 7/4) with schizophrenia who had been on stable doses of haloperidol and biperiden were given tandospirone, 30 mg/day, for 4 weeks. The Wechsler Memory Scale-Revised (WMS-R) was administered at baseline and 4 weeks after the addition of tandospirone. The Brief Psychiatric Rating Scale (BPRS; Total, Positive, and Negative subscale scores) and the Simpson-Angus Scale for Extrapyramidal Symptoms (SAS) were also completed on the two occasions. To exclude the possibility of a practice effect on the WMS-R test, 11 age-matched patients with schizophrenia (M/F = 7/4) were tested at baseline and after a 4-week interval.

RESULTS

Repeated measures analysis of variance revealed a significant time by group (patients with or without tandospirone) effect for the Verbal-, but not the Visual Memory composite scores of the WMS-R test; no significant change was observed in patients without tandospirone, whereas improvement in the Verbal Memory score was noted in patients receiving tandospirone. Moreover, there was improvement in the Inclusion score, an index of memory organization as measured by the Logical Memory subtest of WMS-R, only in patients with tandospirone. Scores on the BPRS and SAS were improved during treatment with tandospirone, but the effects did not reach statistical significance.

CONCLUSIONS

The results suggest that adjunctive treatment with 5-HT(1A) agonists may improve some types of memory function in schizophrenia.

Effects of olanzapine and other antipsychotics on cognitive function in chronic schizophrenia: a longitudinal study

This study aimed to determine the effect of olanzapine and other antipsychotic drugs on cognitive functions after 6months of treatment. Baseline, 3month and 6month psychopathological and cognitive evaluations were made. Thirty-eight partially responsive outpatients with DSM-IV chronic schizophrenia diagnosis were included in the study. On the indication of their attending psychiatrists, 21 patients initiated treatment with olanzapine, and 17 remained on their previous treatment with other antipsychotic drugs. Cognitive assessments were blind to medication and psychopathological status. The olanzapine group presented a significantly greater improvement in negative symptomatology and verbal memory than the comparison group in repeated-measures of MANOVAs between baseline, 3month and 6month assessments. These differences remained statistically significant after covarying out gender, treatment with other atypical antipsychotics, biperidene doses and changes in positive and negative symptoms. In order to match previous differences between groups, cognitive baseline scores for each test were introduced as covariates, resulting in a significant improvement for the olanzapine group in negative symptomatology and the interference task of the Stroop test.We then re-analyzed the data, dividing the comparison group into two groups: risperidone-treated patients (n=9) and patients receiving conventional antipsychotic drugs (n=8). Post-hoc analyses between groups were carried out with baseline cognitive assessment as covariate. The olanzapine group improved significantly more than the risperidone group in negative symptomatology and in the interference task of Stroop test. The improvement in the number of categories of the Wisconsin Card Sorting Test was higher in risperidone patients than in those receiving olanzapine or conventional antipsychotic treatment. Conventional antipsychotic drugs did not present a significant improvement over atypical antipsychotic drugs in any cognitive function. In summary, in patients suffering from chronic schizophrenia, atypical antipsychotic agents were associated with slight differential improvements over time in attentional, verbal memory and executive functions compared with conventional neuroleptic drugs. No differential improvements were found in social functioning, verbal fluency, non-verbal domains of memory or visuo-motor abilities.

Relationship between symptom dimensions and neurocognitive functioning in schizophrenia: a meta-analysis of WCST and CPT studies. Wisconsin Card Sorting Test. Continuous Performance Test

Cognitive deficits have been hypothesized to be differentially related to the negative, positive and disorganization dimensions of schizophrenia symptoms. In this article, we quantitatively review the published literature on the relationships between symptom dimensions in schizophrenia and performance on the two most widely applied tests of executive functioning and sustained attention, the Wisconsin Card Sorting Test (WCST) and the Continuous Performance Test (CPT). Meta-analyses were conducted on studies that reported correlational data for the relations between performance on these tests and scales of positive and negative symptoms. The more recent distinction between disorganization and reality distortion was also taken into account. The results showed statistically significant relationships of negative symptoms with worse performance on the WCST and the CPT. Disorganization symptoms showed a significant positive correlation with perseverations on the WCST, but not with CPT performance. In contrast, reality distortion symptoms and general scores for all positive symptoms did not correlate with either measure. Although some correlations were statistically significant, the observed associations between psychiatric symptoms and cognitive performance were typically weak, suggesting relative independence of these disease processes.

Psychomotor Performance Under Neuroleptic Treatment in Schizophrenia

Abstract: Cognitive dysfunction has been recognized as an important clinical feature of schizophrenia. The possible pharmacological effect of neuroleptics on cognitive and psychomotor function including driving ability is crucial for rehabilitation of schizophrenic patients. Atypical neuroleptics such as risperidone have been shown to improve cognitive deficits in schizophrenics. We conducted a naturalistic nonrandomized clinical study to determine the effect of risperidone on psychomotor function compared to haloperidol in schizophrenic patients. In this study the psychomotor performance of 26 patients, who met the ICD-10 and DSM-IV criteria for schizophrenia, was assessed by means of ART-90, a computer-based Act & React Testsystem. 11 patients were on risperidone (mean dosage 4.0 mg) and 15 patients on haloperidol (mean dosage 10.5 mg). Patients were examined at discharge after psychopathological stabilization. In some relevant items the patients in the haloperidol group showed more impaired performance compared to the patients in the risperidone group. These preliminary data indicate a possible beneficial effect of risperidone compared to haloperidol on psychomotor performance and driving ability. Further randomized trials are necessary.

Schizophrenia: family studies and treatment of spectrum disorders

A substantial part of the contribution of genetic studies to the treatment of schizophrenia involves its emphasis on reliable and valid diagnoses. One consequence of this focus is the recognition that schizophrenic illness is broader than the diagnostic entity of schizophrenia itself, and instead consists of a “spectrum” of related disorders. Because some of the symptoms in these disorders differ from each other, they provide an opportunity to determine which ones reflect a common etiology. To the extent that such symptoms are identifiable, they may provide a foundation for treatment and even prevention strategies. In this paper, we focus on a clinical condition - “schizotaxia” - that may reflect the liability for schizophrenia. To characterize the nature and extent of this proposed syndrome, we will review results from family studies in our laboratory, and consider conceptual foundations and criteria for assessment. A more general consideration of treatment strategies for schizophrenia spectrum disorders follows, along with suggestions for future research. Our initial attempts to treat and validate schizotaxia are encouraging, and raise the possibility that early treatment might eventually prevent or attenuate the development of other, more severe disorders in the schizophrenia spectrum, including schizophrenia itself.

Improvement in cognition associated with novel antipsychotic drugs: a direct drug effect or reduction of EPS?

BACKGROUND

Administration of novel, versus classic, antipsychotic agents to patients suffering from psychosis is associated both with moderately better scores on cognitive tests, and with fewer extrapyramidal symptoms (EPS). Because improved motor functioning may enable better performance on some components of cognitive test batteries, and because the advantages of the novel antipsychotics on cognitive performance are not very large, it is sometimes difficult to discern if improvement in a given cognitive task is due to a direct effect of the novel antipsychotic drug, or is secondary to the novel drug's decreased propensity to induce EPS. In an attempt to distinguish between these two possibilities, the present study examined the ability of patients suffering from schizophrenia receiving classic, versus novel antipsychotics, to perform a computerized visuo-motor test (VMT). VMT assesses planning capabilities, attention and executive functions known to be impaired in schizophrenia, which are suggested to be affected by novel antipsychotics.

METHODS

Seventy-six patients suffering from schizophrenia or schizophreniform disorder, receiving haloperidol (23 patients, mean dose 10.01+/-6.1mg/day), olanzapine (26 patients, mean dose 10.56 +/- 4.9 mg/day) or risperidone (27 patients, mean dose 4.35 +/- 1.7 mg/day) were assessed for EPS using the parkinsonian subscale of the Extrapyramidal Symptom Rating Subscale (ESRS), and with the VMT.

RESULTS

Cognitive functioning as measured by the VMT was better for patients receiving risperidone or olanzapine, compared with those receiving haloperidol (F=6.636, df=2,67, P=0. 002), while the patients receiving haloperidol or risperidone suffered from more severe EPS compared with the patients receiving olanzapine (F=3.996, df=2,71, P=0.023).

DISCUSSION

Although the patients receiving risperidone suffered from EPS similar in severity to the EPS of the patients receiving haloperidol, their performance on a task involving visuo-motor and attentional skills was similar to that of the patients receiving olanzapine. This finding implies that there is a dissociation between the antipsychotic drug's ability to affect cognitive functioning, and EPS. This dissociation indirectly suggests that the advantages offered by novel antipsychotics on cognitive performance are a direct effect, rather than being entirely mediated by improved movement abilities.

Prodromal schizophrenia and atypical antipsychotic treatment

Early recognition and intervention in psychosis is the focus of more intensive research. In this paper, we critically review the ideas that have emerged in this field. We also propose a model or hypothesis for testing in the prodromal phase of schizophrenia. Attention to practical and ethical issues, particularly with the use of atypical antipsychotics in one arm of the protocol, is addressed. Studies by Yung and Falloon describe prodromal intervention with psychosocial strategies and time-limited low potency neuroleptics, respectively, that suggest benefits of such a model. Although we have respect for the DSM system, this paper is written more from a Bleulerian than Kraepelinian perspective in that we emphasize affective, cognitive, and negative symptoms in addition to positive symptoms. The paper recognizes the strong conceptual disagreements implicit in this area stemming not only from Kraepelin and Bleuler but work from the 1930s by Cameron. The clinical research advocated is timely in that the atypicals are more congruent to the Bleulerian conception with a neurodevelopmental hypothesis of schizophrenia. We also have exciting new imaging and genetic technologies to refine our concepts of schizophrenia and its prodromal and premorbid phases.