Cerebral cortical gray expansion associated with two second-generation antipsychotics

Inferior parietal lobule volume and schneiderian first-rank symptoms in antipsychotic-naïve schizophrenia: a 3-tesla MRI study

BACKGROUND

As per Frith's neuro-cognitive model, inferior parietal lobule (IPL) is implicated in the pathogenesis of Schneiderian first-rank symptoms (FRS) in schizophrenia. The specific role of IPL structural abnormalities in the pathogenesis of FRS is yet to be ascertained.

MATERIALS AND METHODS

Using 3-tesla MRI scanner, this first-time study examined antipsychotic-naïve schizophrenia patients ( n = 28) (patients with FRS [FRS +]: N = 14, M: F = 7:7; and patients without FRS [FRS-]: N = 14, M: F = 7:7) in comparison with sex-, handedness-, education- and socioeconomic status-matched healthy controls (n = 14, M: F = 7:7). The volume of IPL was measured using a three-dimensional, interactive, semi-automated analysis, with good inter-rater reliability.

RESULTS

FRS + patients showed significant volume deficit in right IPL in comparison with healthy controls (F = 4.0; P=.028) after controlling for the potential confounding effects of age, sex and intracranial volume.

CONCLUSIONS

Right IPL volume deficit in FRS+patients adds further support to the Frith's model of FRS in schizophrenia.

Early striatal hypertrophy in first-episode psychosis within 3 weeks of initiating antipsychotic drug treatment

BACKGROUND

We and others have reported that patients experiencing their first episode of psychosis already have significant structural brain abnormalities. Antipsychotics seem to reverse subcortical volume deficits after months of treatment. However, the early impact of medication on brain morphology is not known.

METHOD

Forty-eight individuals in their first episode of psychosis underwent magnetic resonance imaging (MRI) brain scanning. Twenty-six were antipsychotic naive and 22 were newly treated with antipsychotic medication for a median period of 3 weeks. In each group, 80% of subjects received a diagnosis of schizophrenia. The two groups were balanced for age, sex, handedness, ethnicity, height, years of education, paternal socio-economic status (SES) and Positive and Negative Syndrome Scale (PANSS) score. Group differences in whole-brain grey matter were compared voxel by voxel, using Brain Activation and Morphological Mapping (BAMM) software. We also conducted testing of group differences with region-of-interest (ROI) measurements of the caudate nucleus.

RESULTS

Relative to the untreated group, those receiving antipsychotic medication for 3-4 weeks had significantly greater grey-matter volumes in the bilateral caudate and cingulate gyri, extending to the left medial frontal gyrus. ROI analysis confirmed that, in treated patients, the right and left caudate nuclei were significantly larger by 10% (p<0.039, two-tailed) and 9% (p<0.048, two-tailed) respectively.

CONCLUSIONS

Early striatal grey-matter enlargement may occur within the first 3-4 weeks of antipsychotic treatment. Possible reasons for putative striatal hypertrophy and its implications are discussed.

Increased grey matter densities in schizophrenia patients with negative symptoms after treatment with quetiapine: a voxel-based morphometry study

Among new-generation antipsychotics, quetiapine was found to be associated with a partial 'normalization' of reduced functional activation in prefrontal and temporal areas and studies conducted by our group found a clinical improvement in negative symptoms in addition to restoration of frontal activation in schizophrenia patients with blunted affect after treatment with quetiapine. Here we investigated the parallelism between improved clinical symptoms and grey mater density (GMD) changes in the frontal region after quetiapine treatment in 15 schizophrenia patients. We hypothesize that improvement in clinical symptoms will be associated with change in GMD in prefrontal regions of interest. By using voxel-based morphometry, paired t-test random-effect analysis showed a significant increase in GMD bilaterally in the inferior frontal cortex/orbitofrontal gyrus and anterior cingulate cortex after 5.5 months of treatment with quetiapine. This GMD increase was associated with a significant improvement in negative symptoms. When GMD was correlated with psychiatric assessment scores, there was a negative correlation between GMD in the anterior cingulate cortex and the Rating Scale for Emotional Blunting score (r=-665, P=0.008) and between the orbitofrontal gyrus and the total Positive and Negative Syndrome Scale negative score (r=-764, P=0.001). Results suggest that increased GMD in some frontal regions are associated with an improvement of negative symptoms. Although not unique to quetiapine, it would be reasonable to attribute the GMD changes in the study to treatment.

Effect of antipsychotic drugs on brain morphometry. A randomized controlled one-year follow-up study of haloperidol, risperidone and olanzapine

BACKGROUND

The effect of antipsychotic drugs on brain morphology is under debate. Here we investigate the effects of risperidone, olanzapine and low doses of haloperidol on cortical and subcortical morphometry in first episode drug naïve patients with non-affective psychosis.

METHODS

Morphological variables were measured in three treatment groups (haloperidol=18; risperidone=16; olanzapine=18) and in healthy subjects (N=38) at baseline and after one year. The relationship between brain morphometric changes and changes in clinical scores was also assessed.

RESULTS

At one year, the three antipsychotics had had an equal effect on the gray matter cortical structure, overall and lobes (all p's>0.121.). A significant time-by-group interaction was found in lateral ventricle volume (F2,47=5.65; p=0.006). Post-hoc comparisons revealed a significant increase in lateral ventricles in patients treated with risperidone (p=0.009). Patients exposed to atypicals (olanzapine and risperidone) exhibited a decrease in caudate nucleus volume (p=0.001). In general, brain changes did not account in any significant manner for clinical changes over time in any treatment group.

CONCLUSIONS

We conclude that low doses of haloperidol, risperidone and olanzapine seem to have an equal effect on the gray matter cortical structure after 1 year of treatment. In contrast to typical antipsychotics, atypicals have differential effects on lateral ventricle and caudate nucleus volumes.

Automated MRI parcellation study of regional volume and thickness of prefrontal cortex (PFC) in antipsychotic-naïve schizophrenia

OBJECTIVE

Prefrontal cortical dysfunction is considered to be critical in the pathogenesis of schizophrenia. However, structural magnetic resonance imaging (MRI) studies on the PFC have yielded inconsistent results because of various confounding factors.

METHOD

In this study we examined the volume and thickness abnormalities of the PFC in antipsychotic-naïve schizophrenia patients (n = 51) in comparison with age-, sex-, and handedness-matched (as a group) healthy comparison subjects (n = 47) using a newly described automated MRI parcellation analysis.

RESULTS

Schizophrenia patients showed i) significant volume deficits in bilateral lateral orbitofrontal and left medial orbitofrontal cortices as well as bilateral pars triangularis; and ii) significant thickness deficit in bilateral medial orbitofrontal cortices. Negative syndrome score had a significant negative correlation with the thickness of the left medial orbitofrontal cortex.

CONCLUSION

The study findings emphasize that prefrontal deficit in schizophrenia is differential and involves primarily the regions essential for 'social cognition'.

Cortical grey matter volume and sensorimotor gating in schizophrenia

Prepulse inhibition (PPI) of the startle response, a cross-species measure of sensorimotor gating, provides a valuable tool to study the known inability of a large proportion of individuals with schizophrenia to effectively screen out irrelevant sensory input. The cortico-striato-pallido-thalamic circuitry is thought to be responsible for modulation of PPI in experimental animals. The involvement of this circuitry in human PPI is supported by observations of deficient PPI in a number of neuropsychiatric disorders that are characterised by abnormalities at some level in this circuitry, and findings of recent functional neuroimaging studies in healthy participants. The current study sought to investigate the structural neural correlates of PPI in a sample of 42 stable male outpatients with schizophrenia. Participants underwent magnetic resonance imaging (MRI) at 1.5T and were assessed (off-line) on acoustic PPI using electromyographic recordings of the orbicularis oculi muscle beneath the right eye. Optimised volumetric voxel-based morphometry implemented in SPM2 was used to investigate the relationship of PPI (prepulse onset-to-pulse onset interval 120msec) to regional grey matter (GM) volumes. Significant positive correlations were obtained between PPI and GM volume in the dorsolateral prefrontal, middle frontal and the orbital/medial prefrontal cortices. Our findings are consistent with (a) previous suggestions of susceptibility of PPI to cognitive processes controlled in a 'top down' manner by the cortex and (b) the hypothesis that compromised neural resources in the frontal cortex contribute to reduced PPI in schizophrenia.

Differential clinical, structural and P300 parameters in schizophrenia patients resistant to conventional neuroleptics

Schizophrenia is a heterogeneous clinical condition that may reflect a variety of biological processes. In particular, treatment-resistant (TR) schizophrenia may have a distinct neurobiological substrate. Within the context of clinical data, a simultaneous study with different imaging techniques could help to elucidate differences in cerebral substrates among schizophrenia patients with different responses to treatment. In the present work we used a set of biological data (basal and longitudinal volumetry, and P300 event-related potential measurements) to compare TR and treatment-responsive chronic schizophrenia patients with healthy controls. The TR patients showed higher baseline clinical scores, a more severe basal profile of brain alterations, as well as a different outcome as regards to volume deficits. These data support the notion that biological substrates vary among groups of different psychotic patients, even when they have the same diagnosis, and that those substrates may be related to the response to treatment.

Absence of regional brain volume change in schizophrenia associated with short-term atypical antipsychotic treatment

The first aim of this pilot study was to determine if longitudinal change in caudate volume could be detected in chronic schizophrenic patients after 12 weeks of atypical antipsychotic treatment. A sub-aim of the first aim was to determine if similar results could be obtained from an operator-assisted segmentation tool for volumetric imaging (ITK-SNAP) and voxel-based morphometry (VBM) methods in the caudate. The second aim was to determine if frontal and temporal lobe grey matter, white matter, ventricular and sulcal cerebrospinal fluid volume change could be detected after 12 weeks of atypical antipsychotic treatment with VBM. Ten chronic schizophrenic inpatients, with illness duration averaging 10.6 years, underwent two MRI scans. The first scan was obtained after a mean of 39.4 days of antipsychotic withdrawal. The second MRI was obtained following twelve weeks of atypical antipsychotic treatment. Caudate volume change was first measured with ITK-SNAP. Then the location of grey matter volume change in the caudate was identified with VBM. Finally, the location of frontal and temporal lobe grey matter, white matter, ventricular and sulcal cerebrospinal fluid volume changes were identified with VBM. No longitudinal change in caudate volume or grey matter volume was observed after brief periods of atypical antipsychotic treatment. ITK-SNAP and VBM methods showed very similar results in the caudate. No statistically significant change was identified in the volume of frontal or temporal lobe grey matter, white matter, and lateral, third, or fourth ventricular cerebrospinal fluid. Although the results do not directly show that brief periods of atypical antipsychotic treatment are associated with basal ganglia and cortical volume change, there is much evidence to suggest that such an association exists.

Regional thinning of the cerebral cortex in schizophrenia: effects of diagnosis, age and antipsychotic medication

Morphological abnormalities of the cerebral cortex have been reported in a number of MRI-studies in schizophrenia. Uncertainty remains regarding cause, mechanism and progression of the alterations. It has been suggested that antipsychotic medication reduces total gray matter volumes, but results are inconsistent. In the present study differences in regional cortical thickness between 96 patients with a DSM-IV diagnosis of schizophrenia (n=81) or schizoaffective disorder (n=15) and 107 healthy subjects (mean age 42 years, range 17-57 years) were investigated using MRI and computer image analysis. Cortical thickness was estimated as the shortest distance between the gray/white matter border and the pial surface at numerous points across the entire cortical mantle. The influence of age and antipsychotic medication on variation in global and regional cortical thickness was explored. Thinner cortex among patients than controls was found in prefrontal and temporal regions of both hemispheres, while parietal and occipital regions were relatively spared. Some hemispheric specificity was noted, as regions of the prefrontal cortex were more affected in the right hemisphere, and regions of the temporal cortex in the left hemisphere. No significant interaction effect of age and diagnostic group on variation in cortical thickness was demonstrated. Among patients, dose or type of antipsychotic medication did not affect variation in cortical thickness. The results from this hitherto largest study on the topic show that prefrontal and temporal cortical thinning in patients with schizophrenia compared to controls is as pronounced in older as in younger subjects. The lack of significant influence from antipsychotic medication supports that regional cortical thinning is an inherent feature of the neurobiological disease process in schizophrenia.

The effects of antipsychotic treatment on cerebral structure and function in schizophrenia

This paper analyses the effects of antipsychotic drug treatment on cerebral structure and function in schizophrenia reviewing qualitatively some of the relevant literature on the issue. Magnetic resonance imaging (MRI) studies of brain morphology in patients at different stages of illness and after varying times of neuroleptic exposure and longitudinal studies show possible different effects of first and second generation antipsychotics. This is true also for functional parameters, such as regional cerebral blood flow and metabolism, analysed, both in resting condition and after specific activation paradigms, with such diverse techniques as positron emission tomography (PET), single photon emission computed tomography (SPECT), functional MRI and MR spectroscopy. The possible molecular mechanisms underlying such differences and whether they represent direct drug effects or indirect consequences of their different and specific interactions with the 'natural' pathophysiological trajectory of brain abnormalities in schizophrenia are matter of present research and debate.

Differential effects of typical and atypical antipsychotics on brain myelination in schizophrenia

CONTEXT

Imaging and post-mortem studies provide converging evidence that patients with schizophrenia have a dysregulated developmental trajectory of frontal lobe myelination even in adulthood. Atypical antipsychotics have been shown to have a wide spectrum of efficacy across multiple psychiatric diseases and to be particularly efficacious in treatment resistant cases of disorders such as schizophrenia.

OBJECTIVE

To test the a priori hypothesis that antipsychotic medications may differentially impact frontal lobe myelination in patients with schizophrenia.

DESIGN, SETTING, AND PARTICIPANTS

Participants ranged in age from 18-35 years, were all male, and were recruited by a single group of investigators using the same criteria. Two cohorts of subjects with schizophrenia early in their disease who were treated either with oral risperidone (Ris) or fluphenazine decanoate (Fd) were imaged in conjunction with cohorts of healthy controls. Each cohort was imaged using a different MRI instrument using identical imaging sequences.

MAIN OUTCOME MEASURE

MRI measures of frontal lobe white matter volume.

RESULTS

We estimated differences due to differences in the MRI instruments used in the two studies in the two healthy control groups matched to the patient samples, adjusting for age and other covariates. We then statistically removed those differences (which we assumed were due to instrument effects) from the data in the schizophrenia samples by subtraction. Relative to the differences seen in controls, the two groups of schizophrenic patients differed in their pattern of frontal lobe structure with the Ris-treated group having significantly larger white matter volume than the Fd group.

CONCLUSIONS

The results suggest that the choice of antipsychotic treatment may differentially impact brain myelination in adults with schizophrenia. Prospective studies are needed to confirm this finding. MRI can be used to dissect subtle differences in brain tissue characteristics and thus could help clarify the effect of pharmacologic treatments on neurodevelopmental and pathologic processes in vivo.

No association between dorsolateral prefrontal gray matter deficit and N-acetyl aspartate ratios in schizophrenia

The cellular substrates of cortical volume deficit in schizophrenia are unclear. We may hypothesize that, if that deficit was related to a decrease in the amount in neuronal tissue, it should correlate with N-acetyl aspartate levels. We studied a group of 34 schizophrenia patients (of them, 17 first episodes) with both structural and spectroscopic magnetic resonance (MR). Using the data of 50 controls, we were able to calculate for each case residuals of gray matter and cortical cerebrospinal fluid (CSF) in the dorsolateral prefrontal (DLPF) region, representing the deviation from the expected values in normals, given individual intracranial volume and age. Although our patients showed a significant deficit in gray matter and excess in cortical CSF in the DLPF region, that deficit was unrelated to N-acetyl aspartate levels. This was also true for the chronic and first episode groups analyzed separately. These results do not support a neuronal tissue deficit as contributing to the cortical volume deficit in schizophrenia, at least in the DLPF region.

Prefrontal but not temporal grey matter changes in males with first-episode schizophrenia

INTRODUCTION

Changes of brain morphology are now considered as a part of the pathology of schizophrenia. Voxel-based morphometry may be used to study regional changes of the grey matter in the whole brain. It is advantageous to study first-episode patients to prevent the influence of many possible biasing factors when trying to identify primary pathological processes underlying the manifestation of the illness.

OBJECTIVE

To investigate regional grey matter changes in the first-episode schizophrenia patients.

METHODS

Optimized voxel-based morphometry was used to detect changes in grey matter volume in 22 patients with first-episode schizophrenia compared with 18 healthy volunteers of comparable age, gender and handedness.

RESULTS

The first-episode schizophrenia group had significantly reduced grey matter volume in the prefrontal cortex (inferior and middle prefrontal gyrus, cingulate gyrus). We identified no differences in the temporal cortex.

CONCLUSION

Our data support the theoretical assumption that prefrontal dysfunction underlines the primary pathology and clinical manifestation of schizophrenia. We are inclined to explain the differences in the pattern of morphological changes reported in other first-episode studies--especially the lack of changes in the temporal cortex--by heterogeneity of schizophrenia, potential progression and antipsychotic medication effect.

Prefrontal cortex and insight in schizophrenia: a volumetric MRI study

Previous studies have suggested a relationship between frontal lobe-based neuropsychological functions and insight in schizophrenia. There is some evidence linking both smaller whole brain volume and frontal cortical atrophy to poor insight in this population. We investigated the relationship between total as well as specific prefrontal regional volumes and insight in schizophrenia. Twenty-eight stable outpatients with schizophrenia underwent magnetic resonance imaging scanning and assessment for insight. Insight was measured using the Birchwood self-report Insight Scale and the Expanded Schedule of Assessment of Insight. The whole brain and prefrontal regional (superior frontal, middle frontal, inferior frontal and orbitofrontal) volumes were then manually measured using the Cavalieri method and established criteria. Twenty healthy subjects were also scanned to provide control data for volumetric assessments. Smaller total prefrontal grey matter volume was moderately associated with a lower level of insight into the presence of illness. At the prefrontal sub-regional level, volumes of the superior, inferior and orbitofrontal regions contributed to this relationship, especially in males. It is concluded that smaller prefrontal grey matter volume is associated with poor insight into the presence of illness in stable schizophrenia patients. Future research should examine the association of specific dimensions of insight with frontal as well as non-frontal regional brain volumes.

Regional change in brain morphometry in schizophrenia associated with antipsychotic treatment

The purpose of this pilot study was to: (1) determine if regional brain volume change occurs in schizophrenia patients during very short periods of withdrawal from, or stable treatment with, antipsychotics, and; (2) compare results of region-of-interest (ROI) to voxel-based morphometry (VBM) methods. In two small groups of schizophrenic inpatients, magnetic resonance imaging was performed before and after antipsychotic withdrawal, and at two time points during stable chronic antipsychotic treatment. Regional brain volumes were measured using ROI methods. Grey matter volume was measured with VBM. The medication withdrawal group showed no effect of treatment state or antipsychotic type on regional brain volumes with ROI analysis, but effects of both treatment state and antipsychotic type on grey matter volume were observed with VBM in right middle frontal, right medial frontal, right and left superior frontal, right cingulate, and right superior temporal gyrii as well as in the right and left hippocampal gyrii. The chronic stable treatment group showed an effect of time on right caudate, left hippocampal, and total cerebrospinal fluid volumes with ROI analysis, while effects of both time and antipsychotic type were observed with VBM on grey matter volume in the left superior temporal lobe. No findings survived correction for multiple comparisons. A positive correlation between regional volume change and emerging psychopathology was demonstrated using ROI methods in the medication withdrawal group. Treatment state and emergent symptoms in schizophrenia patients were associated with regional volume change over very short time periods. Longitudinal regional brain volume change in schizophrenia patients is likely physiologic and therefore potentially reversible.

Use of magnetic resonance imaging in tracking the course and treatment of schizophrenia

Confirming the early conceptualization of Bleuler (1911) and Kraepelin (1919), magnetic resonance imaging (MRI) studies have demonstrated structural and functional brain abnormalities, predominantly involving the frontal and temporal lobes, in schizophrenia. Most of the abnormalities are already present at illness onset. However, there is, growing evidence for treatment-related neural changes in schizophrenia, such as enlargement of the caudate nucleus (neurotoxic effect) with the use of typical antipsychotics and increases in cortical volumes and improved functional responses (neurotrophic effect) with the use of atypical antipsychotics. More recently, brain changes during the prodrome and transition-to-illness stages of schizophrenia have begun to be characterized. Another area of importance is the use of MRI, as a biological marker, to monitor and define partial or full resistance to medication. Understanding the trait- and state-related influences of brain abnormalities during the course of the illness is critical for developing effective treatment and possibly prevention strategies in schizophrenia.

Understanding structural brain changes in schizophrenia

Schizophrenia is a chronic progressive disorder that has at its origin structural brain changes in both white and gray matter. It is likely that these changes begin prior to the onset of clinical symptoms in cortical regions, particularly those concerned with language processing. Later, they can be detected by progressive ventricular enlargement. Current magnetic resonance imaging (MRI) technology can provide a valuable tool for detecting early changes in cortical atrophy and anomalous language processing, which may be predictive of who will develop schizophrenia.

The role of the phosphatidylinositide 3-kinase–protein kinase B pathway in schizophrenia

Neuroanatomical studies of brains from schizophrenic patients report evidence for neuronal dystrophy, while in genetic studies in schizophrenia there is evidence for mutations in growth factors and the downstream enzymes phosphatidylinositide 3-kinase (PI3K) and protein kinase B (PKB). Since the PI3K-PKB pathway is involved in cellular growth and proliferation, reduced activity of this cascade in schizophrenia could at least partly explain the neuronal dystrophy. Risk factors for schizophrenia, such as corticosteroids and cannabis, suppress the activity of the PI3K-PKB pathway. Conversely, estrogen and vitamin D, 2 factors with a moderate protective activity in schizophrenia, electroconvulsive shock therapy, and chronic treatment with antipsychotic compounds stimulate the pathway. Reduced activity of the PI3K-PKB pathway makes the brain more susceptible to virus infections, anoxia, and obstetric complications (recognized risk factors for schizophrenia), whereas a diminution of growth factor levels towards the end of puberty could contribute to an increase in schizophrenia symptoms observed around that time. On the other hand, constitutive (over)activation of the PI3K-PKB pathway increases cancer risk. Consequently, the presumed hypoactivity of the PI3K-PKB cascade might provide a partial explanation for the remarkable epidemiological finding of a reduced cancer rate in schizophrenic patients. Recognition of the role of a dysfunctional PI3K-PKB pathway in schizophrenia might help in the discovery of hitherto undetected causative gene mutations and could also lead to novel therapeutic approaches. However, a major challenge that remains to be solved is how the PI3K-PKB pathway can be activated without increasing the risk of cancer.

Effects of antipsychotics on brain structure

PURPOSE OF REVIEW

This review highlights the recent findings of different effects of typical and atypical antipsychotics on brain structure.

RECENT FINDINGS

Studies examining the effect of treatment with typical antipsychotics on brain structure revealed a significant increase in basal ganglia volumes and decreased grey matter volume in different cortical regions. These volume changes were detectable even after a 12-week treatment. In contrast to these results, treatment with atypical antipsychotics does not seem to change basal ganglia volumes in neuroleptic-naïve patients. Moreover, switching from typical to atypical antipsychotic treatment reduces the increased basal ganglia volume to normal values compared with healthy controls. Only the volumes of thalamus and cortical grey matter increased after atypical antipsychotic treatment.

SUMMARY

Currently, there is growing evidence that atypical antipsychotics might ameliorate structural changes caused by the disease process underlying schizophrenia and effects of typical antipsychotics. Further studies have to investigate the mechanism leading to these varying effects on brain structure.

From clinical research to clinical practice: a 4-year review of ziprasidone

Ziprasidone is a second-generation antipsychotic that received Food and Drug Administration approval in February 2001. It has a unique receptor profile that includes high-affinity antagonist activity at dopamine D2 receptors, inverse agonist activity at serotonin (5-HT)2A receptors, agonist activity at 5-HTlA receptors, and a relatively high affinity for the serotonin and norepinephrine transporters. The 5-HTIA affinity, together with the inhibitory effect on mono-amine reuptake, may underlie the hypothesized beneficial effects on comorbid affective and cognitive abnormalities in schizophrenia and schizoaffective disorder. The short-term efficacy of ziprasidone for core positive symptoms of schizophrenia appears to be comparable to other conventional and atypical antipsychotics. The short-term efficacy of ziprasidone in acute mania has been established based on two 3-week, double-blind, placebo-controlled trials.Open-label treatment for up to 52 weeks confirms the sustained efficacy and safety of ziprasidone in bipolar disorder. Maintenance studies in schizophrenia and schizoaffective disorder indicate that long-term ziprasidone therapy is effective in preventing relapse, while maintaining cognitive and psychosocial benefits. The safety database suggests that the overall cardiovascular and cerebrovascular risk associated with ziprasidone is lower than with other atypicals, with notably lower risk of drug-related increases in weight, glucose, or lipids. The data also suggest a modestly increased risk of QTc prolongation that is not dose related or linked to torsades de pointes. Switching to ziprasidone from other atypicals appears to improve both clinical symptoms and metabolic parameters, though more studies are needed to fully characterize these benefits. This monograph summarizes the efficacy, tolerability, and safety of oral ziprasidone in the treatment of schizophrenia, schizoaffective disorder, and bipolar mania.