Cognition, functioning and quality of life in schizophrenia treatment: results of a one-year randomized controlled trial of olanzapine and quetiapine

The Effect of Antipsychotics on Cognition in Schizophrenia-A Current Narrative Review

The majority of schizophrenia-affected individuals display deficiencies in multiple cognitive domains such as attention, working memory, long-term memory, and learning, deficiencies that are stable throughout the disease. The purpose of this narrative review was to examine the effect of antipsychotics on several cognitive domains affected by schizophrenia. Methods: We searched MEDLINE, Elsevier, Scopus, and DOAJ databases for randomized controlled trials and other studies investigating the effects of typical and atypical antipsychotics on cognition in patients with schizophrenia in studies conducted in the last decade. Results: The majority of studies included in this review showed that antipsychotics (especially SGAs) have positive effects on both cognition and general psychopathology of schizophrenia. We mention that treatment with antipsychotic substances represents an ongoing effort of the researchers, who are constantly searching for the best approach to meet the mental health needs of schizophrenia patients. Conclusions: Even with those positive results, it should be noted that more studies are needed in order to fully observe the various effects of certain antipsychotic substances on cognition.

Prospects for Neurotrophic Factor-Based Early Intervention in Schizophrenia: Lessons Learned from the Effects of Antipsychotic Drugs on Cognition, Neurogenesis, and Neurotrophic Factors

Although reducing psychotic symptoms in schizophrenia has been a major focus of therapeutic interventions for decades, improving cognition is considered a better predictor of functional outcomes. However, the most commonly prescribed antipsychotic drugs (APDs) show only marginal beneficial effects on cognition in patients with schizophrenia. The neural mechanisms underlying cognitive disturbances in schizophrenia remain unknown that making drug development efforts very challenging. Since neurotrophic factors are the primary architects of neurogenesis, synaptic plasticity, learning, and memory, the findings from preclinical and clinical studies that assess changes in neurogenesis and neurotrophic factors and their relationship to cognitive performance in schizophrenia, and how these mechanisms might be impacted by APD treatment, may provide valuable clues in developing therapies to combat cognitive deficit in schizophrenia. Numerous evidence produced over the years suggests a deficit in a wide spectrum of neurotrophic factors in schizophrenia. Since schizophrenia is considered a neurodevelopmental disorder, early intervention with neurotrophic factors may be more effective in ameliorating the cognitive deficits and psychopathological symptoms associated with this pathology. In this context, results from initial clinical trials with neurotrophic factors and their future potential to improve cognition and psychosocial functioning in schizophrenia are discussed.

Oral and long-acting antipsychotics for relapse prevention in schizophrenia-spectrum disorders: a network meta-analysis of 92 randomized trials including 22,645 participants

According to current evidence and guidelines, continued antipsychotic treatment is key for preventing relapse in people with schizophrenia-spectrum disorders, but evidence-based recommendations for the choice of the individual antipsychotic for maintenance treatment are lacking. Although oral antipsychotics are often prescribed first line for practical reasons, long-acting injectable antipsychotics (LAIs) are a valuable resource to tackle adherence issues since the earliest phase of disease. Medline, EMBASE, PsycINFO, CENTRAL and CINAHL databases and online registers were searched to identify randomized controlled trials comparing LAIs or oral antipsychotics head-to-head or against placebo, published until June 2021. Relative risks and standardized mean differences were pooled using random-effects pairwise and network meta-analysis. The primary outcomes were relapse and dropout due to adverse events. We used the Cochrane Risk of Bias tool to assess study quality, and the CINeMA approach to assess the confidence of pooled estimates. Of 100 eligible trials, 92 (N=22,645) provided usable data for meta-analyses. Regarding relapse prevention, the vast majority of the 31 included treatments outperformed placebo. Compared to placebo, "high" confidence in the results was found for (in descending order of effect magnitude) amisulpride-oral (OS), olanzapine-OS, aripiprazole-LAI, olanzapine-LAI, aripiprazole-OS, paliperidone-OS, and ziprasidone-OS. "Moderate" confidence in the results was found for paliperidone-LAI 1-monthly, iloperidone-OS, fluphenazine-OS, brexpiprazole-OS, paliperidone-LAI 1-monthly, asenapine-OS, haloperidol-OS, quetiapine-OS, cariprazine-OS, and lurasidone-OS. Regarding tolerability, none of the antipsychotics was significantly worse than placebo, but confidence was poor, with only aripiprazole (both LAI and OS) showing "moderate" confidence levels. Based on these findings, olanzapine, aripiprazole and paliperidone are the best choices for the maintenance treatment of schizophrenia-spectrum disorders, considering that both LAI and oral formulations of these antipsychotics are among the best-performing treatments and have the highest confidence of evidence for relapse prevention. This finding is of particular relevance for low- and middle-income countries and constrained-resource settings, where few medications may be selected. Results from this network meta-analysis can inform clinical guidelines and national and international drug regulation policies.

Antipsychotics, Metabolic Adverse Effects, and Cognitive Function in Schizophrenia

Cognitive impairment is a core symptom domain of schizophrenia. The effect of antipsychotics, the cornerstone of treatment in schizophrenia, on this domain is not fully clear. There is some evidence suggesting that antipsychotics may partially improve cognitive function, and that this improvement may vary depending on the specific cognitive domain. However, this research is confounded by various factors, such as age, duration/stage of illness, medication adherence, and extrapyramidal side effects that complicate the relationship between antipsychotics and cognitive improvement. Furthermore, antipsychotics-particularly the second generation, or "atypical" antipsychotics-can induce serious metabolic side effects, such as obesity, dyslipidemia and type 2 diabetes, illnesses which themselves have been linked to impairments in cognition. Thus, the inter-relationships between cognition and metabolic side effects are complex, and this review aims to examine them in the context of schizophrenia and antipsychotic treatment. The review also speculates on potential mechanisms underlying cognitive functioning and metabolic risk in schizophrenia. We conclude that the available literature examining the inter-section of antipsychotics, cognition, and metabolic effects in schizophrenia is sparse, but suggests a relationship between metabolic comorbidity and worse cognitive function in patients with schizophrenia. Further research is required to determine if there is a causal connection between the well-recognized metabolic adverse effects of antipsychotics and cognitive deficits over the course of the illness of schizophrenia, as well as, to determine underlying mechanisms. In addition, findings from this review highlight the importance of monitoring metabolic disturbances in parallel with cognition, as well as, the importance of interventions to minimize metabolic abnormalities for both physical and cognitive health.

Risperidone Added to Psychostimulant in Children with Severe Aggression and Attention-Deficit/Hyperactivity Disorder: Lack of Effect on Attention and Short-Term Memory

OBJECTIVE

Professionals have periodically expressed concern that atypical antipsychotics may cause cognitive blunting in treated patients. In this study, we report data from a double-blind, randomized, controlled study of stimulant plus placebo versus combined stimulant and risperidone to evaluate the effects of the atypical antipsychotic on attention and short-term memory.

METHODS

A total of 165 (n = 83 combined treatment; n = 82 stimulant plus placebo) children with attention-deficit/hyperactivity disorder and severe physical aggression, aged 6-12 years, were evaluated with Conners' Continuous Performance Test (CPT-II) and the Wechsler Intelligence Scale for Children-III (WISC) Digit Span subscale at baseline, after 3 weeks of stimulant-only treatment, and after six additional weeks of randomized treatment (stimulant+placebo vs. stimulant+risperidone).

RESULTS

At 3 weeks, improvement on CPT-II performance (Commissions and Reaction Time Standard Error; p < 0.001) and on Digit Span memory performance (p < 0.006) was noted for the full sample. At study week 9, no difference in CPT-II or Digit Span performance was observed between the randomized groups (ps = 0.41 to 0.83).

CONCLUSIONS

Similar to other studies, we found no deleterious effects on attention and short-term memory associated with short-term use of risperidone. NCT00796302.

Impact of duration of untreated psychosis and premorbid intelligence on cognitive functioning in patients with first-episode schizophrenia

BACKGROUND

The neurotoxic hypothesis suggests that psychosis is toxic to the brain leading to clinical consequences. In this study, we hypothesized that a longer duration of untreated psychosis (DUP) in first episode schizophrenia (FES) patients is associated with poorer cognitive functioning, and that higher premorbid intelligence buffers against DUP-related cognitive impairment.

METHOD

Eighty-one FES patients completed a neuropsychological battery, the Brief Assessment of Cognition in Schizophrenia (BACS). Composite scores of the BACS, which were normalized to a matched healthy control of seventy-three subjects, were used as an index of general cognition. A median split using the Wide Range Achievement Test-Reading Test scores was used to divide the patients into low versus high premorbid IQ groups. Hierarchical linear regression was performed to examine predictors of general cognition, including DUP.

RESULTS

Longer DUP was found to be a significant predictor of poorer general cognition. In addition, DUP predicted general cognition in the low premorbid IQ group but not in the high premorbid IQ group.

CONCLUSIONS

Our findings demonstrate that longer DUP in FES patients is associated with worse cognitive scores, and that this association is more pronounced in a subgroup of patients who have lower premorbid intelligence. Our results suggest the importance of earlier identification and management of patients with low premorbid IQ, given that their cognition may be more vulnerable to the toxicity of psychosis.

[Subjective cognition in schizophrenia]

OBJECTIVES

Given the extent, magnitude and functional significance of the neurocognitive deficits of schizophrenia, growing attention has been paid recently to patients' self-awareness of their own deficits. Thus far, the literature has shown either that patients fail to recognize their cognitive deficits or that the association between subjective and objective cognition is weak in schizophrenia. The reasons for this lack of consistency remain unexplained but may have to do, among others, with the influence of potential confounding clinical variables and the choice of the scale used to measure self-awareness of cognitive deficits. In the current study, we sought to examine the relationships between subjective and objective cognitive performance in schizophrenia, while controlling for the influence of sociodemographic and psychiatric variables.

METHODS

Eighty-two patients with a schizophrenia-spectrum disorder (DSM-IV criteria) were recruited. Patients' subjective cognitive complaints were evaluated with the Subjective Scale to Investigate Cognition in Schizophrenia (SSTICS), the most frequently used scale to measure self-awareness of cognitive deficits in schizophrenia. Neurocognition was evaluated with working memory, planning and visual learning tasks taken from Cambridge Neuropsychological Tests Automated Battery. The Stroop Color-Word test was also administered. Psychiatric symptoms were evaluated with the Positive and Negative Syndrome Scale and the Calgary Depression Scale for Schizophrenia. The relationships between subjective and objective cognition were evaluated with multivariate hierarchic linear regression analyses, taking into consideration potential confounders such as sociodemographic and psychiatric variables. Finally, a factor analysis of the SSTICS was performed.

RESULTS

For the SSTICS total score, the regression analysis produced a model including two predictors, namely visual learning and Stoop interference performance, explaining a moderate portion of the variance. Visual learning performance was the most consistent predictor of most SSTICS subscores (e.g. episodic memory, attention, executive functioning, language and praxis). Modest associations were found between the PANSS cognitive factor and objective cognition (e.g. Stroop interference, visual learning, and working memory). Finally, the factor analysis revealed a 6-factor solution that echoes the classification of the items of the SSTICS based on the neuropsychological literature.

CONCLUSIONS

Using a scale having good internal validity, as shown by the factor analysis, the current study highlighted modest associations between subjective and objective cognitive performance, which suggests that schizophrenia patients are only partially aware of their own cognitive deficits. The results also showed a lack of correspondence between the impaired cognitive domain and the domain of cognitive awareness. It should be noted that clinicians were not better than patients at evaluating their cognitive deficits. Future research will need to determine if the observations reported here are schizophrenia-specific or not.

Do negative symptoms of schizophrenia change over time? A meta-analysis of longitudinal data

BACKGROUND

Negative symptoms are a core component of schizophrenia which can severely impact quality of life and functional outcomes. These symptoms are understood to be highly stable but this has not been tested in a meta-analysis, despite the wealth of longitudinal data available.

METHOD

A systematic review of the literature was conducted, with eligible studies pooled into a random-effects meta-analysis. Planned meta-regressions were conducted to evaluate the impact of factors known to induce secondary negative symptoms, in addition to other possible sources of heterogeneity.

RESULTS

The main analysis included 89 samples from 41 studies, totalling 5944 participants. Negative symptoms were found to significantly reduce in all treatment interventions, including in placebo and treatment as usual conditions, with a medium effect size (ES) present across all study conditions (ES = 0.66, 95% confidence interval 0.56-0.77, I(2) = 94.0%). In a multivariate meta-regression, only the type of scale used was found to significantly influence negative symptom change. No difference in outcome was found between studies that excluded patients with a high level of positive or depressive symptoms, compared to those that did not.

CONCLUSIONS

Negative symptoms were found to reduce in almost all schizophrenia outpatient samples. A reduction was found across all conditions, with effect sizes ranging from small to large depending upon the condition type. These findings challenge the convention that negative symptoms are highly stable and suggest that they may improve to a greater extent than what has previously been assumed.

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

OBJECTIVE

To investigate the effect of second-generation antipsychotics on cognitive function in patients diagnosed with schizophrenia or schizoaffective disorder.

METHOD

Multiple-treatments meta-analysis model.

RESULTS

On cognitive composite score, sertindole was superior to clozapine, effect size (ES) 0.87; 95% CI: 0.12-1.63, quetiapine, ES 0.75; 95% CI: 0.00-1.49, and first-generation antipsychotics (FGAs), ES 0.89; 95% CI: 0.14-1.64. Analyses on each cognitive domain showed clozapine, ES 0.37; 95% CI: 0.00-0.74, olanzapine, ES 0.31; 95%CI: 0.02-0.59, quetiapine, ES 0.34; 95% CI: 0.03-0.64, and FGAs, ES 0.51; 95% CI: 0.18-0.83 performing poorer on verbal working memory than ziprasidone, as well as FGAs performing poorer than risperidone, ES 0.31; 95% CI: 0.04-0.58. On executive function, sertindole performed better than clozapine, ES 0.82; 95% CI: 0.06-1.58, olanzapine, ES 0.81; 95% CI: 0.07-1.55, quetiapine, ES 0.76; 95% CI: 0.02-1.51, ziprasidone, ES 0.90; 95% CI: 0.14-1.67, and FGAs, ES 0.83; 95% CI: 0.08-1.58. On processing speed, FGAs performed poorer than sertindole, ES 0.97; 95% CI: 0.02-1.91, and quetiapine, ES 0.36; 95% CI: 0.01-0.72. On long-term verbal working memory, clozapine performed poorer than olanzapine, ES 0.41; 95% CI: 0.06-0.76. On verbal fluency, FGAs performed poorer than olanzapine, ES 0.26; 95% CI: 0.01-0.50, and clozapine, ES 0.44; 95% CI: 0.06-0.81. Lastly, FGAs, ES 0.41; 95% CI: 0.04-0.78, and clozapine, ES 0.44; 95% CI: 0.05-0.83, performed poorer on visuospatial skill compared to olanzapine.

CONCLUSION

The meta-analysis was able to detect some trends in the data analyzed, but did not show any drug having a uniform positive cognitive profile.

Role of quetiapine beyond its clinical efficacy in bipolar disorder: From neuroprotection to the treatment of psychiatric disorders (Review)

The aim of the present review was to discuss the following aspects of treatment with quetiapine in psychiatric disorders: i) Neurocognition and functional recovery in bipolar disorder (BD); ii) neuroprotective profile in different models; and iii) potential off-label indications. A PubMed search was conducted of articles published in English between 2000 and 2012 on quetiapine, cross-referenced with the terms ‘anxiety’, ‘attention deficit disorder’, ‘borderline personality disorder’, ‘dementia’, ‘insomnia’, ‘major depressive disorder’ (MDD), ‘obsessive-compulsive disorder’, ‘post-traumatic stress disorder’, ‘remission’, ‘cognition’, ‘neurobiology’, ‘neuroprotection’, ‘efficacy’ and ‘effectiveness’. Articles were selected from meta-analyses, randomized clinical trials and open trials, and the results were summarized. Quetiapine, when studied in off-label conditions, has shown efficacy as a monotherapy in MDD and general anxiety disorder. Quetiapine also appears to exhibit a small beneficial effect in dementia. The review of other conditions was affected by methodological limitations that precluded any definitive conclusions on the efficacy or safety of quetiapine. Overall, the present review shows evidence supporting a potential role for quetiapine in improving cognition, functional recovery and negative symptoms in a cost-effective manner in BD. These benefits of quetiapine are potentially associated with its well-described neuroprotective effects; however, further studies are clearly warranted.

La conscience des déficits neurocognitifs dans la schizophrénie : une méta-analyse

Contexte La schizophrénie est un trouble allant de pair avec un manque d’autocritique par rapport aux délires et aux hallucinations. En contrepartie, on en sait beaucoup moins en ce qui concerne la conscience des patients par rapport à leurs déficits cognitifs, qui sont des symptômes clés de ce trouble psychiatrique. Afin de faire la synthèse de l’état de la connaissance à ce sujet, nous avons effectué une méta-analyse de 22 études comprenant 1609 patients. Les analyses ont révélé que les patients rapportent davantage de plaintes subjectives que les sujets sains. La corrélation entre la cognition subjective et objective s’est avérée faible toutefois. Les études utilisant la Scale to Investigate Cognition in Schizophrenia ont produit des corrélations plus fortes que celles utilisant d’autres échelles de plaintes subjectives. La relation entre la cognition subjective et les symptômes dépressifs s’est avérée comparable à la relation entre la cognition subjective et la cognition objective. Enfin, une relation faible a été observée entre la cognition subjective et l’autocritique par rapport aux symptômes positifs. Les résultats de la présente méta-analyse montrent que les patients atteints de la schizophrénie se plaignent de déficits cognitifs, mais qu’ils n’ont pas une représentation claire de la nature de ceux-ci, ce qui confirme l’existence de déficits méta-cognitifs dans la schizophrénie.

Quetiapine versus other atypical antipsychotics for schizophrenia

BACKGROUND

In many countries, second-generation ('atypical') antipsychotic drugs have become the first-line drug treatment for people with schizophrenia. It is not clear how the effects of the various second-generation antipsychotic drugs differ.

OBJECTIVES

To evaluate the effects of quetiapine compared with other second-generation (atypical) antipsychotic drugs in the treatment of people with schizophrenia and schizophrenia-like psychoses.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register (May 2010), inspected references of all identified studies, and contacted relevant pharmaceutical companies, drug approval agencies and authors of trials for additional information.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing oral quetiapine with other oral forms of atypical antipsychotic medication in people with schizophrenia or schizophrenia-like psychoses.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For dichotomous data, we calculated risk ratios (RRs) and their 95% confidence intervals (CIs) on an intention-to-treat basis based on a random-effects model. We calculated number needed to treat for an additional beneficial outcome (NNTB) where appropriate. For continuous data, we calculated mean differences (MDs), again based on a random-effects model.

MAIN RESULTS

Efficacy data tended to favour the control drugs over quetiapine (Positive and Negative Syndrome Scale (PANSS) total score vs olanzapine: 11 RCTs, n = 1486, mean quetiapine endpoint score 3.67 higher, CI 1.95 to 5.39, low quality; vs risperidone: 13 RCTs, n = 2155, mean quetiapine endpoint score 1.74 higher, CI 0.19 to 3.29, moderate quality; vs paliperidone: 1 RCT, n = 319, mean quetiapine endpoint score 6.30 higher, CI 2.77 to 9.83, moderate quality), but the clinical meaning of these data is unclear. No clear mental state differences were noted when quetiapine was compared with clozapine, aripiprazole or ziprasidone. Compared with olanzapine, quetiapine produced slightly fewer movement disorders (7 RCTs, n = 1127, RR use of antiparkinson medication 0.51, CI 0.32 to 0.81, moderate quality) and less weight gain (8 RCTs, n = 1667, RR 0.68, CI 0.51 to 0.92, moderate quality) and glucose elevation, but increased QTc prolongation (3 RCTs, n = 643, MD 4.81, CI 0.34 to 9.28). Compared with risperidone, quetiapine induced slightly fewer movement disorders (8 RCTs, n = 2163, RR use of antiparkinson medication 0.5, CI 0.36 to 0.69, moderate quality), less prolactin increase (7 RCTs, n = 1733, MD -35.25, CI -43.59 to -26.91) and some related adverse effects but greater cholesterol increase (6 RCTs, n = 1473, MD 8.57, CI 4.85 to 12.29). On the basis of limited data, compared with paliperidone, quetiapine induced fewer parkinsonian side effects (1 RCT, n = 319, RR use of antiparkinson medication 0.64, CI 0.45 to 0.91, moderate quality) and less prolactin increase (1 RCT, n = 319, MD -49.30, CI -57.80 to -40.80) and weight gain (1 RCT, n = 319, RR weight gain of 7% or more of total body weight 2.52, CI 0.5 to 12.78, moderate quality). Compared with ziprasidone, quetiapine induced slightly fewer extrapyramidal adverse effects (1 RCT, n = 522, RR use of antiparkinson medication 0.43, CI 0.2 to 0.93, moderate quality) and less prolactin increase. On the other hand, quetiapine was more sedating and led to greater weight gain (2 RCTs, n = 754, RR 2.22, CI 1.35 to 3.63, moderate quality) and cholesterol increase when compared with ziprasidone.

AUTHORS' CONCLUSIONS

Available evidence from trials suggests that most people who start quetiapine stop taking it within a few weeks (around 60%). Comparisons with amisulpride, sertindole and zotepine do not exist. Although efficacy data favour olanzapine and risperidone compared with quetiapine, the clinical meaning of these data remains unclear. Quetiapine may produce fewer parkinsonian effects than paliperidone, aripiprazole, ziprasidone, risperidone and olanzapine. Quetiapine appears to have a similar weight gain profile to risperidone, as well as clozapine and aripiprazole (although data are very limited for the latter two comparators). Quetiapine may produce greater weight gain than ziprasidone and less weight gain than olanzapine and paliperidone. Most data that have been reported within existing comparisons are of very limited value because of assumptions and biases within them. Much scope is available for further research into the effects of this widely used drug.

Measuring quality of life in patients with schizophrenia: an update

In 1997, we published a review in PharmacoEconomics about quality of life (QOL) measurement in patients with schizophrenia. The objective of this article is to provide an update, as well as to revisit the development of the construct of QOL and its measurement as applied to schizophrenia. Since our previous article, there has been significant growth in the number of publications about QOL in schizophrenia. Unfortunately, alongside this significant increase in research interest, a number of concerns have also risen about the limitations and lack of impact the concept of QOL has on clinical care and health-policy decision making. A number of concerns previously outlined (such as lack of consensus on a uniform definition of QOL) continue to be an issue. However, we believe that a uniform definition may not be possible, and instead, it may be preferable to have several definitions, which may enrich the concept and broaden its usefulness. Some of the scales we reviewed in 1997 continue to be in use, while others are now rarely or never used. New scales with better psychometrics have been introduced, but most are without theoretical or conceptual foundation. On the other hand, the field of scaling in general has been changing over the past few years and is moving towards a new approach for scale development, based on item response theory, item banks and computer adaptive testing. Unfortunately, this has not extended to QOL in schizophrenia. There continues to be a dearth of theoretical and conceptual models for QOL in schizophrenia, which seems to create the perception that the construct lacks a good theoretical and scientific foundation. One of the major gaps identified in this review is the recognized lack of impact of QOL measurements on clinical management or policy decision making. The majority of publications continue to focus on measurement rather than what to do with the data. The lack of strategies to integrate QOL data in clinical care, as well as the failure to contribute to policy decisions, particularly in cost analysis or resource allocations, has created the perception that the construct of QOL in schizophrenia is not that useful. It is evident that, for QOL in schizophrenia to regain its promise, researchers must take the ultimate next step beyond measurement: to develop credible strategies for integrating QOL data in clinical practice. Additionally, more focused research is needed to demonstrate the role of QOL, not only as an outcome in itself but also as a contributor to other outcomes, such as adherence to medications, more satisfaction, less resource utilization and so on. Since self-appraisal of QOL does not happen in a vacuum but relates to the total human experience in all its biological, psychosocial and environmental aspects, particular attention must also be focused on important neurobiological dimensions such as affect and cognition. Both are significantly affected by the illness itself and its treatment.

Effects of quetiapine and sertindole on subchronic ketamine-induced deficits in attentional set-shifting in rats

RATIONALE

Prefrontal cortical dysfunctions, including an impaired ability to shift perceptual attentional set, are core features of schizophrenia. Nevertheless, the effectiveness of second-generation antipsychotic drugs in treating specific prefrontal dysfunctions remains equivocal.

OBJECTIVES

To model schizophrenia-like cognitive inflexibility in rats, we evaluated the effects of repeated administration of ketamine, the noncompetitive antagonist of the N-methyl-D: -aspartate receptor, after a washout period of 14 days in the attentional set-shifting task (ASST). Next, we investigated whether the atypical antipsychotics quetiapine and sertindole would alleviate the ketamine-induced set-shifting impairment.

METHODS

Ketamine (30 mg/kg) was administered intraperitoneally to rats once daily for 5 or 10 consecutive days to assess its efficacy in producing cognitive impairment. The ASST was performed 14 days following the final drug administration. Quetiapine (0.63, 1.25 or 2.5 mg/kg) or sertindole (2.5 mg/kg) was administered per os 120 min before testing.

RESULTS

The results of the present study demonstrate that ketamine treatment for 10 but not 5 days significantly and specifically impaired rats' performance in the extra-dimensional shift (EDs) stage of the ASST. This cognitive inflexibility was reversed by acute administration of sertindole or quetiapine. Quetiapine also promoted set-shifting in cognitively unimpaired control animals.

CONCLUSION

The data presented here show that subchronic administration of ketamine induces cognitive inflexibility after a washout period. This cognitive deficit likely reflects clinically relevant aspects of cognitive dysfunction encountered in schizophrenic patients. The beneficial effects of quetiapine on set-shifting may have therapeutic implications for the treatment of schizophrenia and other disorders associated with frontal-dependent cognitive impairments.

Neurocognitive effectiveness of quetiapine, olanzapine, risperidone, and ziprasidone: a pragmatic, randomized trial

PURPOSE

Cognitive effects of second generation antipsychotics (SGAs) are indicated in efficacy studies but the generalizability of the results may be limited by rigid designs and selected samples. The aim of this naturalistic, industry-independent study is to investigate whether differential neurocognitive effectiveness can be found among olanzapine, quetiapine, risperidone, and ziprasidone in a clinically relevant sample with psychosis.

SUBJECTS AND METHODS

Adult patients acutely admitted to an emergency ward for psychosis were randomized to risperidone, olanzapine, quetiapine or ziprasidone and followed for up to 2 years. Participants were assessed repeatedly using the Positive and Negative Syndrome Scale and a repeatable neurocognitive test battery.

RESULTS

A total of 226 patients were included and 171 patients underwent neurocognitive assessments. The sample had a global cognitive performance score at baseline about one standard deviation below that of the general population. The ziprasidone group had the fastest increase in global functioning which was significantly superior to that of the olanzapine group for the entire follow-up period. Before 90 days, the quetiapine group had the fastest increase which was statistically superior to the olanzapine group.

DISCUSSION

Ziprasidone and quetiapine demonstrated superiority to olanzapine in increasing global neurocognitive performance in this naturalistic sample.

Comparison of metabolic changes in patients with schizophrenia during randomized treatment with intramuscular olanzapine long-acting injection versus oral olanzapine

Metabolic changes were examined in patients with schizophrenia during treatment with either oral olanzapine or olanzapine long-acting injection (LAI). Data were collected from patients who had been stabilized on oral olanzapine (10, 15, or 20 mg/day) for ≥4 weeks and then randomized to either continued olanzapine oral treatment (n = 322) or LAI (n = 599; 150 mg/2 weeks, 405 mg/4 weeks, or 300 mg/2 weeks) for up to 24 weeks. Mean and categorical changes in metabolic parameters were analyzed. Mean changes in weight, glucose, and most lipids were generally not significantly different between treatment groups. Weight changes over time followed similar patterns and were not significantly different at endpoint between the two treatment-formulation groups. Low-density lipoprotein cholesterol decreased significantly less among olanzapine LAI-treated patients. Percentages of patients with potentially clinically significant changes in blood glucose and lipid concentrations were similar for the two treatments. Percentages of patients experiencing adverse events related to weight, diabetes, or dyslipidemia were also not significantly different between treatments. Metabolic changes in patients with schizophrenia appeared generally similar during treatment with oral olanzapine or olanzapine LAI.

Cognitive effects of six months of treatment with quetiapine in antipsychotic-naïve first-episode schizophrenia

Effects of quetiapine on cognition were assessed in a group of first-episode antipsychotic-naïve patients with schizophrenia (N=24). A comprehensive battery of neuropsychological tests was administered at baseline and after 6 months of treatment with quetiapine. In order to examine retest effects, a matched healthy control group (N=24) was also tested at baseline and after 6 months. Only few differential changes were observed between patients and healthy controls. Of 8 cognitive domains examined, only significant changes in executive function suggested possible ameliorating effects of quetiapine. Patients also improved on speed of processing; however, this was parallel to the retest effects found in healthy controls. When covaried for differences at baseline, patients showed smaller improvements in speed of processing than the retest effects found in controls, as well as a lack of retest effects on sustained attention and working memory that were found in healthy controls. The main result of the study is that there was very little evidence of efficacy of quetiapine on cognition. The study also indicated a lack of normal retest effects in patients compared to controls.

Comparison of metabolic and prolactin variables from a six-month randomised trial of olanzapine and quetiapine in schizophrenia

Schizophrenia patients have a potential increased risk of metabolic dysregulation during antipsychotic treatments. Our objective was to compare changes in prolactin and metabolic variables (glucose, lipids and weight) as a post-hoc analysis from a six-month, randomised, controlled study of olanzapine (OLZ, n = 171; 10-20 mg/day) or quetiapine (QUE, n = 175; 300-700 mg/day). No statistically significant treatment group differences for baseline to endpoint mean changes in body mass index (P = 0.209) or weight (P = 0.250) were observed. There was a greater incidence of clinically significant weight gain (defined as > or =7% increase from baseline) in OLZ (19.2%) compared to QUE (13.2%)-treated patients (P = 0.181). No statistically significant treatment group differences for lipids and glucose variables, either as mean change from baseline to endpoint or treatment-emergent (TE) categorical changes were found (P > or = 0.05). Incidence rates for TE diabetes were similar between treatment groups 2.5% (n = 4) in the OLZ-treatment group and 1.3% (n = 2) in the QUE-treatment group (P = 0.685). Hyperprolactinaemia was present at baseline in many patients (OLZ 32.9%; QUE 31.4%), but after 2 weeks of treatment prolactin values had reverted to normal for nearly all patients (OLZ 100%; QUE 99.4%). There were no significant treatment differences in any variable between cohorts.

Auditory and visual P300 reflecting cognitive improvement in patients with schizophrenia with quetiapine: a pilot study

We recorded event-related potentials (ERPs) in patients with schizophrenia before and after treatment with quetiapine, to investigate this drug's effects on cognitive function. Auditory and visual oddball stimulus discrimination paradigms were presented to patients with schizophrenia (N=20) before and after 3months' treatment with quetiapine. The 2-stimulus auditory oddball paradigm used a standard tone (1000Hz, 75dB, 80%) and a target tone (2000Hz, 75dB, 20%). The 2-stimulus visual oddball paradigm used a standard stimulus (small circle, 80%) and a target stimulus (large circle, 20%). Patients' severity of psychopathology was initially evaluated with the Positive and Negative Syndrome Scale (PANSS) and was likewise re-evaluated after treatment. After treatment with quetiapine, patients' P300 amplitudes increased over baseline for both tasks (auditory stimuli, P<0.01; visual stimuli, P<0.01) and their P300 latencies for both target stimuli decreased significantly (auditory stimuli, P<0.001; visual stimuli, P<0.01). Visual P300 amplitude was negatively correlated with the severity of positive symptoms at the Fz electrode before the treatment (r=-0.45, P<0.05). After treatment with quetiapine, there were no significant correlations between severity of positive or negative symptoms and visual P300 amplitudes for midline electrodes. These findings suggest that the reduced and delayed P300 may be a state marker for schizophrenia, which may in turn be modulated by positive symptoms, and also suggest that the amplitude and latency for both auditory and visual tasks may be decreased by quetiapine treatment. Based on these results, we suggest that the atypical antipsychotic quetiapine may improve some aspects of cognitive domains in patients with schizophrenia.

Olanzapine versus other atypical antipsychotics for schizophrenia

BACKGROUND

In many countries of the industrialised world second generation ("atypical") antipsychotics have become the first line drug treatment for people with schizophrenia. The question as to whether, and if so how much, the effects of the various second generation antipsychotics differ is a matter of debate. In this review we examined how the efficacy and tolerability of olanzapine differs from that of other second generation antipsychotics.

OBJECTIVES

To evaluate the effects of olanzapine compared to other atypical antipsychotics for people with schizophrenia and schizophrenia-like psychosis.

SEARCH STRATEGY

1. Electronic searching We searched the Cochrane Schizophrenia Group Trials Register (April 2007) which is based on regular searches of BIOSIS, CENTRAL, CINAHL, EMBASE, MEDLINE and PsycINFO.2. Reference searching We inspected the reference of all identified studies for more trials.3. Personal contact We contacted the first author of each included study for missing information.4. Drug companies We contacted the manufacturers of all atypical antipsychotics included for additional data.

SELECTION CRITERIA

We included all randomised trials that used at least single-blind (rater-blind) design, comparing oral olanzapine with oral forms of amisulpride, aripiprazole, clozapine, quetiapine, risperidone, sertindole, ziprasidone or zotepine in people with schizophrenia or schizophrenia-like psychosis.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For dichotomous data we calculated relative risks (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random effects model. We calculated numbers needed to treat/harm (NNT/NNH) where appropriate. For continuous data, we calculated weighted mean differences (WMD) again based on a random effects model.

MAIN RESULTS

The review currently includes 50 studies and 9476 participants which provided data for six comparisons (olanzapine compared to amisulpride, aripiprazole, clozapine, quetiapine, risperidone or ziprasidone). The overall attrition from the included studies was considerable (49.2%) leaving the interpretation of results problematic.Olanzapine improved the general mental state (PANSS total score) more than aripiprazole (2 RCTs, n=794, WMD -4.96 CI -8.06 to -1.85), quetiapine (10 RCTs, n=1449, WMD -3.66 CI -5.39 to -1.93), risperidone (15 RCTs, n=2390, WMD -1.94 CI -3.31 to -0.58) and ziprasidone (4 RCTs, n=1291, WMD -8.32 CI -10.99 to -5.64), but not more than amisulpride or clozapine. This somewhat better efficacy was confirmed by fewer participants in the olanzapine groups leaving the studies early due to inefficacy of treatment compared to quetiapine (8 RCTs, n=1563, RR 0.56 CI 0.44 to 0.70, NNT 11 CI 6 to 50), risperidone (14 RCTs, n=2744, RR 0.78 CI 0.62 to 0.98, NNT 50 CI 17 to 100) and ziprasidone (5 RCTs, n=1937, RR 0.64 CI 0.51 to 0.79, NNT 17, CI 11 to 33).Fewer participants in the olanzapine group than in the quetiapine (2 RCTs, n=876, RR 0.56 CI 0.41 to 0.77, NNT 11 CI 7 to 25) and ziprasidone (2 RCTs, n=766, RR 0.65 CI 0.45 to 0.93, NNT 17 CI 9 to 100) treatment groups, but not in the clozapine group (1 RCT, n=980, RR 1.28 CI 1.02 to 1.61, NNH not estimable), had to be re-hospitalised in the trials.Except for clozapine, all comparators induced less weight gain than olanzapine (olanzapine compared to amisulpride: 3 RCTs, n=671, WMD 2.11kg CI 1.29kg to 2.94kg; aripiprazole: 1 RCT, n=90, WMD 5.60kg CI 2.15kg to 9.05kg; quetiapine: 7 RCTs, n=1173, WMD 2.68kg CI 1.10kg to 4.26kg; risperidone: 13 RCTs, n=2116, WMD 2.61kg CI 1.48kg to 3.74kg; ziprasidone: 5 RCTs, n=1659, WMD 3.82kg CI 2.96kg to 4.69kg). Associated problems such as glucose and cholesterol increase were usually also more frequent in the olanzapine group.Other differences in adverse effects were less well documented. Nevertheless, olanzapine may be associated with slightly more extrapyramidal side effects than quetiapine (use of antiparkinson medication (6 RCTs, n=1090, RR 2.05 CI 1.26 to 3.32, NNH 25 CI 14 to 100), but less than risperidone (use of antiparkinson medication 13 RCTs, n=2599, RR 0.78 CI 0.65 to 0.95, NNH 17 CI 9 to 100) and ziprasidone (use of antiparkinson medication 4 RCTs, n=1732, RR 0.70 CI 0.50 to 0.97, NNH not estimable). It may also increase prolactin somewhat more than aripiprazole, clozapine and quetiapine, but clearly less so than risperidone (6 RCTs, n=1291, WMD -22.84 CI -27.98 to -17.69).

AUTHORS' CONCLUSIONS

Olanzapine may be a somewhat more efficacious drug than some other second generation antipsychotic drugs. This small superiority in efficacy needs to be weighed against a larger weight gain and associated metabolic problems than most other second generation antipsychotic drugs, except clozapine. These conclusions are tentative due to the large number of people leaving the studies early which possibly limits the validity of the findings. Further large, well-designed trials are necessary to establish the relative effects of different second generation antipsychotic drugs.

Cognitive profiles of healthy siblings of schizophrenia patients: application of the cognitive domains of the MATRICS consensus battery

Even though a large body of data suggests the presence of various types of cognitive deficits in the unaffected relatives of schizophrenia patients, more study is needed to clarify the comparative sensitivities of specific cognitive measures for relative-control differences. In this study, the authors compared the cognitive profiles of unaffected siblings of schizophrenia patients and those of patients and normal controls, and attempted to identify cognitive markers that might be associated with genetic liability to schizophrenia. Eighty-eight clinically stable schizophrenia patients, 44 healthy patient siblings, and 100 normal controls were evaluated using comprehensive neuropsychological tests. The domain structure of the MATRICS consensus cognitive battery was adopted, and both domain scores and individual test scores were used in the analysis. Performances of the sibling group were intermediate between those of patients and controls on most measures. A significant difference between the sibling and control groups was observed only in the Category Fluency Test. This cognitive deficit might be caused by familial predisposition to schizophrenia and could be a candidate of endophenotype for schizophrenia.

Neurocognition and its influencing factors in the treatment of schizophrenia-effects of aripiprazole, olanzapine, quetiapine and risperidone

BACKGROUND

To examine influencing variables of neurocognition in patients with schizophrenia and to predict cognition during antipsychotic treatment.

METHODS

Data were obtained from patients with an acute episode of schizophrenia participating in two double-blind and one open label trial comparing the effects of different atypical antipsychotics on cognition. In total, 129 patients were enrolled in this analysis. Cognitive function was assessed at admission, week 4 and 8. Efficacy and tolerability were assessed weekly using the Positive and Negative Syndrome Scale (PANSS) and the Simpson Angus Sale (SAS). Patients were treated with aripirazole, olanzapine, quetiapine and risperidone. Regression analysis including mixed effect models was performed.

RESULTS

A significant improvement in all cognitive domains was observed from baseline to week 8. Regarding the antipsychotic treatment applied quetiapine seemed to achieve the most favourable cognitive improvement. Negative and depressive symptoms, the patient's age and the concomitant and antipsychotic treatment applied were observed to significantly influence and predict neurocognition.

CONCLUSION

The results may indicate that schizophrenia is a static disorder with trait and state dependent cognitive components especially in the memory domains. The influence of negative and depressive symptoms should be considered in daily clinical routine.

Quetiapine versus other atypical antipsychotics for schizophrenia

BACKGROUND

In many countries of the industrialised world second generation ('atypical') antipsychotic drugs have become the first line drug treatment for people with schizophrenia. It is not clear how the effects of the various second generation antipsychotic drugs differ.

OBJECTIVES

To evaluate the effects of quetiapine compared with other second generation antipsychotic drugs for people with schizophrenia and schizophrenia-like psychosis.

SEARCH STRATEGY

We searched the Cochrane Schizophrenia Group Trials Register (April 2007), inspected references of all identified studies, and contacted relevant pharmaceutical companies, drug approval agencies and authors of trials for additional information.

SELECTION CRITERIA

We included all randomised control trials comparing oral quetiapine with oral forms of amisulpride, aripiprazole, clozapine, olanzapine, risperidone, sertindole, ziprasidone or zotepine in people with schizophrenia or schizophrenia-like psychosis.

DATA COLLECTION AND ANALYSIS

We extracted data independently. For dichotomous data we calculated relative risks (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. We calculated numbers needed to treat/harm (NNT/NNH) where appropriate. For continuous data, we calculated weighted mean differences (WMD) again based on a random-effects model.

MAIN RESULTS

The review currently includes 21 randomised control trials (RCTs) with 4101 participants. These trials provided data on four comparisons - quetiapine versus clozapine, olanzapine, risperidone or ziprasidone.A major limitation to all findings is the high number of participants leaving studies prematurely (57.6%) and the substantial risk of biases in studies. Efficacy data favoured olanzapine and risperidone compared with quetiapine (PANSS total score versus olanzapine:10 RCTs, n=1449, WMD 3.66 CI 1.93 to 5.39; versus risperidone: 9 RCTs, n=1953, WMD 3.09 CI 1.01 to 5.16), but clinical meaning is unclear. There were no clear mental state differences when quetiapine was compared with clozapine or ziprasidone.Compared with olanzapine, quetiapine produced slightly fewer movement disorders (6 RCTs, n=1090, RR use of antiparkinson medication 0.49 CI 0.3 to 0.79, NNH 25 CI 14 to 100) and less weight gain (7 RCTs, n=1173, WMD -2.81 CI -4.38 to -1.24) and glucose elevation, but more QTc prolongation (3 RCTs, n=643, WMD 4.81 CI 0.34 to 9.28). Compared with risperidone, quetiapine induced slightly fewer movement disorders (6 RCTs, n=1715, RR use of antiparkinson medication 0.5 CI 0.3 to 0.86, NNH 20 CI 10 to 100), less prolactin increase (6 RCTs, n=1731, WMD -35.28 CI -44.36 to -26.19) and some related adverse effects, but more cholesterol increase (5 RCTs, n=1433, WMD 8.61 CI 4.66 to 12.56). Compared with ziprasidone, quetiapine induced slightly fewer extrapyramidal adverse effects (1 RCT, n=522, RR use of antiparkinson medication 0.43 CI 0.2 to 0.93, NNH not estimable) and prolactin increase. On the other hand quetiapine was more sedating and led to more weight gain (2 RCTs, n=754, RR 2.22 CI 1.35 to 3.63, NNH 13 CI 8 to 33) and cholesterol increase than ziprasidone.

AUTHORS' CONCLUSIONS

Best available evidence from trials suggests that most people who start quetiapine stop taking it within a few weeks. Comparisons with amisulpride, aripiprazole, sertindole and zotepine do not exist. Most data that has been reported within existing comparisons are of very limited value because of assumptions and biases within them. There is much scope for further research into the effects of this widely used drug.

Quetiapine treatment and improved cognitive functioning in borderline personality disorder

OBJECTIVE

We aimed to assess whether executive functioning improved over time in a sample of borderline personality disorder (BPD) subjects that took part in a quetiapine treatment trial.

METHODS

Performance on the following neurocognitive tasks was assessed at enrolment and at the end of the 12 weeks quetiapine treatment: Trail Making Task, Word Fluency Task and Tower of London Task. Forty-one BPD patients were recruited, of whom 32 completed the trial. An intention-to-treat analysis with a mixed linear model was applied.

RESULTS

The data show that participants significantly improved on most executive functioning measures. Patients' scores decreased significantly (mean [SD] difference; p-value) on the Trail Making Task Part A (11.7 [2.3]; p < 0.0001), Part B (51.8 [9.2]; p < 0.0001) and 'B minus A' (40.1 [8.2]; p < 0.0001), on a Phonological (15.9 [1.6]; p < 0.0001) and Semantic (9.8 [1.1]; p < 0.0001) Verbal Fluency tasks, and on the Tower of London total correct score (2.5 [0.4]; p < 0.0001), total move score (29.5 [4.5]; p < 0.0001) and total time (172.9 [35.8]; p < 0.0001).

CONCLUSIONS

In this study we have demonstrated that executive functioning in BPD is improved after treatment with quetiapine. Neurocognitive measures of executive functioning should be considered as valuable outcomes in the study of treatment efficacy in BPD.

Resource utilization and costs of schizophrenia patients treated with olanzapine versus quetiapine in a Medicaid population

OBJECTIVE

Compare annual health-care costs and resource utilization associated with olanzapine versus quetiapine for treating schizophrenia in a Medicaid population.

METHODS

Adult schizophrenia patients were selected from deidentified Pennsylvania Medicaid claims database (1999–2003). Included patients were continuously enrolled and initiated with olanzapine or quetiapine monotherapy after a 90-day washout period. Treatment costs were calculated for 1-year post-therapy initiation and inflation adjusted to year 2003. To control for selection bias, olanzapine and quetiapine patients were 1:1 matched using an optimal matching algorithm on propensity score, which was generated using logistic regression controlling for demographics, prior drug therapy, utilization, and costs. Treatment costs for the matched cohorts were compared directly, as well as using a difference-in-difference analysis.

RESULTS

A total of 6929 patients treated with olanzapine and 2321 with quetiapine met inclusion criteria. Quetiapine patients appeared more severe at baseline. After propensity score matching, 2321 patient pairs had similar baseline characteristics, including total costs. Compared with matched quetiapine patients, for the 1-year postindex period, olanzapine patients had similar drug costs ($6131 vs. $6014, P = 0.326), lower medical costs ($9897 vs. $11,218, P = 0.0128), and lower total health-care costs ($16,028 vs. $17,232, P = 0.0279). Lower psychiatric hospitalization costs account for most of the total cost difference. Difference-in-difference regression analysis confirmed olanzapine's economic advantage. Further adjusting for baseline variations, the total cost advantage of olanzapine patients was $962 (P = 0.032), and was mostly because of reduced psychiatric hospitalization costs of $992 (P = 0.004).

CONCLUSION

Schizophrenia patients treated with olanzapine had lower total costs than quetiapine patients, mostly attributable to reductions in psychiatric hospitalization costs.

Olanzapine compared to quetiapine in adolescents with a first psychotic episode

OBJECTIVE

To compare the efficacy, safety, and tolerability of olanzapine and quetiapine in adolescents with first episode psychosis.

METHOD

Fifty adolescents (age 16 +/- 1.25) with a first episode of psychosis were randomized to quetiapine or olanzapine in a 6-month open label study. Efficacy and side effect scales, as well as vital signs and laboratory data were recorded at baseline, 7, 15, 30, 90, and 180 days (end of study).

RESULTS

Out of the total sample included in the study, 32 patients completed the trial (quetiapine n = 16, olanzapine n = 16). Patients in both treatment groups had a significant reduction in all clinical scales with the exception of the negative scale of the Positive and Negative Symptom Scale (PANSS) for olanzapine and the general psychopathology scale of the PANSS for quetiapine. The only difference between treatment arms on the clinical scales was observed on the patients' strength and difficulties questionnaire (SDQ) scale, with greater improvement for olanzapine. Patients on olanzapine gained 15.5 kg and patients on quetiapine gained 5.5 kg.

CONCLUSION

Olanzapine and quetiapine reduced psychotic symptoms in this adolescent sample. Patients on olanzapine gained significantly more weight. Side effects with both drugs seemed to be more prevalent than those reported in adult studies.

Cognitive-enhancing effects of aripiprazole: a case report

Patients with schizophrenia often present mild to severe cognitive deficits which contribute to their social disability. Second-generation antipsychotics have shown only mild to moderate beneficial effects on cognition. The present case report suggests cognitive enhancing effects of aripiprazole, a dopamine partial agonist, shown to increase dopamine release in prefrontal cortex in animal studies.

The patient was in his first-episode of schizophrenia, and had no previous exposure to first-generation antipsychotics. Before schizophrenia onset his cognitive functioning was poor and he could not attend regular courses to reach his high school degree; he started but was not able to attend the University courses for several years.

After schizophrenia onset, he was treated, in sequence, with olanzapine, amisulpride and aripiprazole. During treatment with the first two second-generation antipsychotics, positive symptoms markedly improved while cognitive functioning remained poor. During treatment with aripiprazole, clinical remission was obtained and the patient was able to attend university courses and pass several examinations. Social functioning was markedly improved.

Aripiprazole demonstrated cognitive enhancing effects in this patient. These effects were long-lasting and paralleled by a positive impact on social functioning.