Progressive atrophy of the frontal lobes in first-episode schizophrenia: interaction with clinical course and neuroleptic treatment

The neurobiology of duration of untreated psychosis: a comprehensive review

Duration of untreated psychosis (DUP) is defined as the time from the onset of psychotic symptoms until the first treatment. Studies have shown that longer DUP is associated with poorer response rates to antipsychotic medications and impaired cognition, yet the neurobiologic correlates of DUP are poorly understood. Moreover, it has been hypothesized that untreated psychosis may be neurotoxic. Here, we conducted a comprehensive review of studies that have examined the neurobiology of DUP. Specifically, we included studies that evaluated DUP using a range of neurobiologic and imaging techniques and identified 83 articles that met inclusion and exclusion criteria. Overall, 27 out of the total 83 studies (32.5%) reported a significant neurobiological correlate with DUP. These results provide evidence against the notion of psychosis as structurally or functionally neurotoxic on a global scale and suggest that specific regions of the brain, such as temporal regions, may be more vulnerable to the effects of DUP. It is also possible that current methodologies lack the resolution needed to more accurately examine the effects of DUP on the brain, such as effects on synaptic density. Newer methodologies, such as MR scanners with stronger magnets, PET imaging with newer ligands capable of measuring subcellular structures (e.g., the PET ligand [11C]UCB-J) may be better able to capture these limited neuropathologic processes. Lastly, to ensure robust and replicable results, future studies of DUP should be adequately powered and specifically designed to test for the effects of DUP on localized brain structure and function with careful attention paid to potential confounds and methodological issues.

A unifying theory for the pathoetiologic mechanism of tardive dyskinesia

INTRODUCTION

Chronic treatment with dopamine D2 receptor antagonists has been proposed to lead to dopamine receptor supersensitivity. Frequently, this is conceptualized as upregulation or changes in the structure or function of the post-synaptic D2 receptor. However, the measured 1.4-fold increase in D2 receptor density and the lack of actual receptor supersensitivity are probably inadequate to explain outcomes such as tardive dyskinesia (TD) and dopamine supersensitivity psychosis.

HYPOTHESIS

Recent data suggest that TD may result from a combination of presynaptic, synaptic, and postsynaptic changes.

DISCUSSION

Presynaptic increase in dopamine release occurs when super-therapeutic blockade of postsynaptic D2 receptors results in excess synaptic unbound dopamine which ultimately ends up being reuptaken by the presynaptic neuron through the dopamine transporter. The increased availability of recycled dopamine results in higher vesicular dopamine concentrations. Since the quantity of neurotransmitter released (known as quanta) is determined by the number of presynaptic neurotransmitter vesicles, the increase in the number (concentration) of dopamine molecules in the vesicles results in a higher concentration of synaptic dopamine with successive depolarization events. Synaptic changes such as the appearance of perforated synapses which is an early step in new synapse formation have been shown in animal models of TD. Finally, postsynaptic increases in D2 receptor expression without demonstration of increased sensitivity or potency has been demonstrated.

CONCLUSION

TD likely develops due to changes across the synapse and terminology such as 'dopamine receptor supersensitivity' can be misleading. 'Synaptic upregulation' may be a more correct term.

Duration of untreated psychosis and its relationship to clinical outcome

Background

A major reason for interest in early intervention for psychotic disorders is the hypothesised relationship between longer duration of untreated psychosis (DUP) and poorer outcome of treatment.

Aims

To critically examine the evidence concerning DUP being related to treatment outcome and possible mediators of any such relationship.

Method

A systematic review of studies in which DUP is assessed and its relationship to treatment outcome is examined. In addition, studies relevant to possible neurotoxic effects of DUP were reviewed.

Results

The research is entirely of a correlational nature and, therefore, firm conclusions regarding causation are not possible. There is, however, substantial evidence of DUP being an independent predictor of treatment outcome, particularly remission of positive symptoms, over the first year or so of treatment. Findings regarding the possible neurotoxic effects of DUP are inconsistent.

Conclusions

There continues to be evidence consistent with DUP influencing aspects of treatment outcome. Non-correlational studies, such as quasi-experimental designs, could provide stronger evidence regarding causality.

Structural neuroimaging across early-stage psychosis: Aberrations in neurobiological trajectories and implications for the staging model

OBJECTIVE

This review critically examines the structural neuroimaging evidence in psychotic illness, with a focus on longitudinal imaging across the first-episode psychosis and ultra-high-risk of psychosis illness stages.

METHODS

A thorough search of the literature involving specifically longitudinal neuroimaging in early illness stages of psychosis was conducted. The evidence supporting abnormalities in brain morphology and altered neurodevelopmental trajectories is discussed in the context of a clinical staging model.

RESULTS

In general, grey matter (and, to a lesser extent, white matter) declines across multiple frontal, temporal (especially superior regions), insular and parietal regions during the first episode of psychosis, which has a steeper trajectory than that of age-matched healthy counterparts. Although the ultra-high-risk of psychosis literature is considerably mixed, evidence indicates that certain volumetric structural aberrations predate psychotic illness onset (e.g. prefrontal cortex thinning), while other abnormalities present in ultra-high-risk of psychosis populations are potentially non-psychosis-specific (e.g. hippocampal volume reductions).

CONCLUSION

We highlight the advantages of longitudinal designs, discuss the implications such studies have on clinical staging and provide directions for future research.

A Computational Analysis of Aberrant Delay Discounting in Psychiatric Disorders

Impatience for reward is a facet of many psychiatric disorders. We draw attention to a growing literature finding greater discounting of delayed reward, an important aspect of impatience, across a range of psychiatric disorders. We propose these findings are best understood by considering the goals and motivation for discounting future reward. We characterize these as arising from either the opportunity costs of waiting or the uncertainty associated with delayed reward. We link specific instances of higher discounting in psychiatric disorder to heightened subjective estimates of either of these factors. We propose these costs are learned and represented based either on a flexible cognitive model of the world, an accumulation of previous experience, or through evolutionary specification. Any of these can be considered suboptimal for the individual if the resulting behavior results in impairments in personal and social functioning and/or in distress. By considering the neurochemical and neuroanatomical implementation of these processes, we illustrate how this approach can in principle unite social, psychological and biological conceptions of impulsive choice.

Minimal evidence that untreated psychosis damages brain structures: a systematic review

INTRODUCTION

A longer duration of untreated psychosis (DUP) is associated with poor outcomes in first-episode psychosis (FEP); however, it is unclear whether this is due to the effects of psychosis on brain structure. We systematically reviewed the literature on the association between the length of untreated psychosis and brain structure in first-episode psychosis.

METHODS

We searched three electronic databases and conducted forward and backward citation searching to identify relevant papers. Studies were included if they: (1) included patients with a psychotic disorder who were treatment naïve or minimally treated; and (2) had correlated measures of DUP or duration of untreated illness (DUI) with structural measures.

RESULTS

We identified 48 studies that met the inclusion criteria. Forty-three examined the correlation between DUP and brain structure, and 19 examined the correlation between DUI and brain structure. There was evidence of significant associations in brain regions considered important in psychosis; however, the proportion of significant associations was low and the findings were inconsistent across studies. The majority of included studies were not primarily designed to examine whether DUP/DUI is correlated with brain structure, and there were methodological limitations in many studies that prevent drawing a strong conclusion.

CONCLUSION

To date, there is minimal evidence of an association between untreated psychosis and brain structure in FEP. Although the body of literature is substantial, there are few hypothesis-driven studies with a primary objective to answer this question. Future studies should be specifically designed to examine whether untreated psychosis has a deleterious effect on brain structure.

Reliability and validity of methods for measuring the duration of untreated psychosis: a quantitative review and meta-analysis

BACKGROUND

The duration of untreated psychosis (DUP) has been associated with a wide range of clinical outcomes, and is considered to be one of the key parameters in managing clinical high risk and first episode psychosis patients. However, considerable discrepancies exist in the way that DUP is estimated in different studies. There is no standard or consensus on which method is most reliable and valid for assessing DUP.

METHODS

This review aimed to quantitatively assess different DUP measurement instruments and definitions by comparing their inter-rater reliability, and their strength of validity in predicting biological and clinical outcomes.

RESULTS

Nine instruments designed for measuring DUP were found. Their inter-rater reliability were found to be adequate to excellent, although quite varied. This analysis did not show that any instrument was clearly outstanding compared to the others, although the limited available data do not exclude this possibility. DUP was also significantly associated with a range of outcomes, although mostly with small effect sizes. However, non-instrument based, ad hoc clinical interviews remained the most common way of measuring DUP. Definitions of onset of psychosis and onset of treatment were inconsistent among studies.

CONCLUSIONS

This review did not find quantitative evidence to support the use of one instrument over another. DUP remains a promising modifiable risk factor for a range of long-term clinical outcomes. Future research should quantify and improve the reliability and validity of the structured instruments for DUP measurement.

Serum brain-derived neurotrophic factor and cognitive functioning in underweight, weight-recovered and partially weight-recovered females with anorexia nervosa

Several studies support the assumption that the brain-derived neurotrophic factor (BDNF) plays an important role in the pathophysiology of eating disorders. In the present cross-sectional and longitudinal study, we investigated BDNF levels in patients with anorexia nervosa (AN) at different stages of their illness and the association with cognitive functioning. We measured serum BDNF in 72 acutely underweight female AN patients (acAN), 23 female AN patients who successfully recovered from their illness (recAN), and 52 healthy control women (HCW). Longitudinally, 30 acAN patients were reassessed after short-term weight gain. The association between BDNF levels and psychomotor speed was investigated using the Trail Making Test. BDNF serum concentrations were significantly higher in recAN participants if compared to acAN patients and increased with short-term weight gain. In acAN patients, but not HCW, BDNF levels were inversely associated with psychomotor speed. AcAN patients with higher BDNF levels also had lower life time body mass indexes. Taken together, our results indicate that serum BDNF levels in patients with AN vary with the stage of illness. Based on the pleiotropic functions of BDNF, changing levels of this neurotrophin may have different context-dependent effects, one of which may be the modulation of cognitive functioning in acutely underweight patients.

The role of untreated psychosis in neurodegeneration: a review of hypothesized mechanisms of neurotoxicity in first-episode psychosis

For over 20 years, studies have tried to measure the association between the duration of untreated psychosis (DUP) and changes in brain morphology. A hypothesis that untreated psychosis is neurotoxic has been postulated, but the mechanisms of that toxicity have not been described. We re-analyzed papers collected for a systematic review to extract data on the hypotheses that have been generated on the potential mechanisms by which DUP could impact brain morphology in first-episode psychosis. Dopaminergic hyperactivity, prolonged hypothalamic-pituitary-adrenal activation, and persistent activity of catecholamines have been hypothesized as mechanisms to explain these associations. However, the question remains as to whether the observed structural changes are permanent or may be reversed via antipsychotic treatment.

Does active psychosis cause neurobiological pathology? A critical review of the neurotoxicity hypothesis

BACKGROUND

Since the neurotoxicity hypothesis was launched in 1991, it has generated a great deal of interest and given rise to several studies investigating the validity of the hypothesis that being psychotic has a toxic effect on the brain. The toxicity argument is used to justify early treatment. This review attempts to assess the studies that have addressed the question: Does an active psychosis, indexed by the duration of untreated psychosis (DUP), cause neurobiological pathology?

METHOD

The validity of the hypothesis has been studied primarily by correlation analyses that assess whether there are significant correlations between DUP and changes in neurocognitive functioning or brain structure. In this review, relevant reports were identified by a literature survey.

RESULTS

Of the 35 studies (33 papers) evaluated, six neurocognitive studies supported the hypothesis and 16 did not. Eight morphology studies supported the hypothesis and five did not. In general, the studies that did not support the neurotoxicity hypothesis were larger in size and had more adequate designs (longitudinal) than those that supported the hypothesis.

CONCLUSIONS

Overall, there is limited empirical evidence for the neurotoxicity hypothesis in the studies reviewed. However, it is possible that there is a threshold value for a toxic effect of psychosis, rather than a linear relationship between DUP and a neurotoxic effect, and that several of the studies evaluated did not have a long enough DUP to detect a toxic effect of active psychosis.

Three-year longitudinal population-based volumetric MRI study in first-episode schizophrenia spectrum patients

BACKGROUND

Schizophrenia is a chronic brain disorder associated with structural brain abnormalities already present at the onset of the illness. Whether these brain abnormalities might progress over time is still under debate.

METHOD

The aim of this study was to investigate likely progressive brain volume changes in schizophrenia during the first 3 years after initiating antipsychotic treatment. The study included 109 patients with a schizophrenia spectrum disorder and a control group of 76 healthy subjects. Subjects received detailed clinical and cognitive assessment and structural magnetic resonance imaging (MRI) at regular time points during a 3-year follow-up period. The effects of brain changes on cognitive and clinical variables were examined along with the impact of potential confounding factors.

RESULTS

Overall, patients and healthy controls exhibited a similar pattern of brain volume changes. However, patients showed a significant lower progressive decrease in the volume of the caudate nucleus than control subjects (F 1,307.2 = 2.12, p = 0.035), with healthy subjects showing a greater reduction than patients during the follow-up period. Clinical and cognitive outcomes were not associated with progressive brain volume changes during the early years of the illness.

CONCLUSIONS

Brain volume abnormalities that have been consistently observed at the onset of non-affective psychosis may not inevitably progress, at least over the first years of the illness. Taking together with clinical and cognitive longitudinal data, our findings, showing a lack of brain deterioration in a substantial number of individuals, suggest a less pessimistic and more reassuring perception of the illness.

The myth of schizophrenia as a progressive brain disease

Schizophrenia has historically been considered to be a deteriorating disease, a view reinforced by recent MRI findings of progressive brain tissue loss over the early years of illness. On the other hand, the notion that recovery from schizophrenia is possible is increasingly embraced by consumer and family groups. This review critically examines the evidence from longitudinal studies of (1) clinical outcomes, (2) MRI brain volumes, and (3) cognitive functioning. First, the evidence shows that although approximately 25% of people with schizophrenia have a poor long-term outcome, few of these show the incremental loss of function that is characteristic of neurodegenerative illnesses. Second, MRI studies demonstrate subtle developmental abnormalities at first onset of psychosis and then further decreases in brain tissue volumes; however, these latter decreases are explicable by the effects of antipsychotic medication, substance abuse, and other secondary factors. Third, while patients do show cognitive deficits compared with controls, cognitive functioning does not appear to deteriorate over time. The majority of people with schizophrenia have the potential to achieve long-term remission and functional recovery. The fact that some experience deterioration in functioning over time may reflect poor access, or adherence, to treatment, the effects of concurrent conditions, and social and financial impoverishment. Mental health professionals need to join with patients and their families in understanding that schizophrenia is not a malignant disease that inevitably deteriorates over time but rather one from which most people can achieve a substantial degree of recovery.

Focal and global brain measurements in siblings of patients with schizophrenia

BACKGROUND

It remains unclear whether structural brain abnormalities in schizophrenia are caused by genetic and/or disease-related factors. Structural brain abnormalities have been found in nonpsychotic first-degree relatives of patients with schizophrenia, but results are inconclusive. This large magnetic resonance imaging study examined brain structures in patients with schizophrenia, their nonpsychotic siblings, and healthy control subjects using global and focal brain measurements.

METHODS

From 155 patients with schizophrenia, their 186 nonpsychotic siblings, and 122 healthy controls (including 25 sibling pairs), whole-brain scans were obtained. Segmentations of total brain, gray matter (GM), and white matter of the cerebrum, lateral and third ventricle, and cerebellum volumes were obtained. For each subject, measures of cortical thickness and GM density maps were estimated. Group differences in volumes, cortical thickness, and GM density were analyzed using Structural Equation Modeling, hence controlling for familial dependency of the data.

RESULTS

Patients with schizophrenia, but not their nonpsychotic siblings, showed volumetric differences, cortical thinning, and reduced GM density as compared with control subjects.

CONCLUSIONS

This study did not reveal structural brain abnormalities in nonpsychotic siblings of patients with schizophrenia compared with healthy control subjects using multiple imaging methods. Therefore, the structural brain abnormalities observed in patients with schizophrenia are for the largest part explained by disease-related factors.

Duration of untreated illness in schizophrenia is not associated with 5-year brain volume change

OBJECTIVES

Evidence for an association between duration of untreated illness (DUI) with clinical and functional outcome or brain volume (change) in schizophrenia patients is inconclusive. We aimed to investigate the relationship between DUI, outcome and brain volume at illness onset or brain volume change during the first five years of the illness in first-episode patients.

METHODS

Magnetic resonance images were acquired at baseline (T0) and after 5-year (T5) of 57 schizophrenia patients. Correlations were calculated in patients between brain volume (change), DUI and outcome variables.

RESULTS

We found no significant correlation between DUI and brain volume (change) in schizophrenia patients. A longer DUI was significantly correlated with higher PANSS scores at T0 and T5, and with higher scores on the Camberwell Assessment of Need scale at T5. Baseline volume of the cerebrum and lateral ventricles, and cerebellum volume (change) were associated with PANSS scores at T0 and T5.

CONCLUSION

Although clinical outcome is associated with both brain volume (change) and DUI, we found no evidence for a relationship between DUI and brain volume (change). DUI and baseline brain volume or 5-year brain volume (change) seem to explain different parts of the variation in clinical outcome.

Review of the operational definition for first-episode psychosis

AIM

Given the growing interest in the study of first-episode psychosis, clinical and research programmes would benefit from a conceptual clarification of how to operationalize 'first-episode psychosis'. We review the variety of definitions in use and discuss their relative merits with respect to both clinical (e.g. early treatment) and research (e.g. obtaining meaningfully homogeneous populations) agendas.

METHODS

We completed a selective review of the literature to investigate how first-episode psychosis was operationally defined.

RESULTS

Operational definitions for 'first-episode psychosis' fall largely into three categories: (i) first treatment contact; (ii) duration of antipsychotic medication use; and (iii) duration of psychosis. Each definitional category contains a number of underlying assumptions that contribute to the strengths and weaknesses of the definition.

CONCLUSIONS

The term 'first-episode psychosis' as used within clinical and research settings is misleading regardless of which operational definition is used. This term is typically used to refer to individuals early in the course of a psychotic illness or treatment rather than individuals who are truly in the midst of a first 'episode' of illness. The alternative of 'recent-onset psychosis' with related definitions based on 'duration of psychosis' is proposed. Based on this review, we provide suggestions with regard to the overarching pragmatic consideration of setting up a clinical service that can attract and assemble a population of early psychosis patients for the related purposes of treatment and research.

Gray matter abnormalities in subjects at ultra-high risk for schizophrenia and first-episode schizophrenic patients compared to healthy controls

Neuroimaging studies have revealed gray matter abnormalities in schizophrenia in various regions of the brain. It is, however, still unclear whether such abnormalities are already present in individuals at ultra-high risk (UHR) for transition into psychosis. We investigated this issue using voxel-based morphometry of structural magnetic resonance images (MRI) and compared UHR patients with first-episode patients with schizophrenia and healthy controls. Gray matter volume maps from high-resolution MR T1-weighted whole brain images were analyzed in a cross-sectional study in 30 UHR patients, 23 first-episode schizophrenic patients and 29 controls. UHR patients showed significantly lower gray matter volume in the cingulate gyrus bilaterally, in the right inferior frontal and right superior temporal gyrus, as well as in the left and right hippocampus in comparison to healthy subjects. First-episode patients with schizophrenia showed smaller gray matter volume in the cingulate cortex bilaterally, in the left orbitofrontal gyrus, in the right inferior frontal and superior temporal gyrus, in the right temporal pole, in the left and right hippocampus, in the left parahippocampus, left amygdala, and in the left fusiform gyrus compared to the UHR patients. This study provides further evidence that gray matter brain volume, especially in the anterior cingulate cortex, is already reduced in the prodromal state of schizophrenia.

Delusions and dorso-medial frontal cortex volume in first-episode schizophrenia: a voxel-based morphometry study

Of the few studies that have directly investigated the neuroanatomical correlates of delusions in patients with recent-onset schizophrenia, a number have paradoxically reported a positive correlation between delusion severity and regional grey matter volume. In order to explore this relationship, 31 patients with first-episode schizophrenia (FES) underwent a clinical interview and a T1-weighted structural MRI scan. Patients' scores on the Delusions subscale of the Positive and Negative Syndrome Scale were correlated with the volume of every voxel in their grey matter images in SPM99. Patients' delusion scores were found to correlate with the volume of a cluster of voxels located in the dorso-medial frontal cortex, centred on the medial frontal gyrus. Post-hoc analysis revealed that this 'region-of-correlation' was volumetrically reduced in the FES patients relative to a group of 21 matched healthy controls. The results of this study support the hypothesis that while a certain level of structural brain atrophy is necessary for delusion formation in patients with FES, excessive structural atrophy may in fact preclude the formation of highly systematized delusions.

Mental health laws that require dangerousness for involuntary admission may delay the initial treatment of schizophrenia

INTRODUCTION

A long duration of untreated psychosis (DUP) is associated with a worse prognosis, an increased risk of suicide and may be linked to serious violence. Mental health laws that require patients to be dangerous to themselves or to others before they can receive involuntary psychiatric treatment may make it more difficult to treat patients in their first episode of psychosis.

METHODS

The mean and median DUP reported in studies of schizophrenia related psychoses were examined. A comparison was made between the DUP reported from jurisdictions that had an obligatory dangerousness criterion (ODC) and those with other criteria for involuntary treatment.

RESULTS

The average mean DUP in samples from jurisdictions with an ODC was 79.5 weeks, but was only 55.6 weeks in those jurisdictions that did not have an ODC (P < 0.007).

CONCLUSIONS

Mental health laws that require the patient to be assessed as dangerous before they can receive involuntary treatment are associated with significantly longer DUP. As reducing DUP is an intervention that can improve the prognosis of schizophrenia, this finding suggests that mental health laws should be amended to allow treatment on grounds other than dangerousness, at least in the crucial first episode of psychosis.

Volume reduction of the left planum temporale gray matter associated with long duration of untreated psychosis in schizophrenia: a preliminary report

A longer duration of untreated psychosis (DUP) in schizophrenia is reported to lead to a poorer clinical outcome, possibly reflecting a neurodegenerative process after the onset of overt psychosis. However, the effect of DUP on brain morphology in schizophrenia is still poorly understood. In this study, we used magnetic resonance imaging to investigate the relation between DUP and volumetric measurements for the superior temporal sub-regions (Heschl's gyrus, planum temporale, and caudal superior temporal gyrus), the medial temporal lobe structures (hippocampus and amygdala), and the frontal lobe regions (prefrontal area and anterior cingulate gyrus) in a sample of 38 schizophrenia patients (20 males and 18 females) whose illness duration was less than five years. We found a significant negative correlation between DUP and the volume of gray matter in the left planum temporale even after controlling for age, age at illness onset, and duration and dosage of neuroleptic medication. There was no such correlation for the other brain regions including each sub-region of the prefrontal cortex (the superior frontal gyrus, middle frontal gyrus, inferior frontal gyrus, ventral medial prefrontal cortex, orbitofrontal cortex, and straight gyrus). When subjects were divided into two groups around the median DUP, the long-DUP group had a significantly smaller planum temporale gray matter than the short-DUP group. These findings may reflect a progressive pathological process in the gray matter of the left planum temporale during the initial untreated phase of schizophrenia, whereas abnormalities in the medial temporal regions might be, as has been suggested from previous longitudinal findings, relatively static at least during the early course of the illness.

Morphology of the orbitofrontal cortex in first-episode schizophrenia: relationship with negative symptomatology

Different studies have documented OFC abnormalities in schizophrenia, but it is unclear if they are present at disease onset or are a consequence of disease process and/or drug exposure. The evaluation of first-episode, drug-naïve subjects allows us to clarify this issue. Magnetic resonance imaging was performed on 43 first-episode, antipsychotic-naïve schizophrenia patients and 53 healthy comparison subjects matched for age, gender, race, and handedness. Gray matter OFC volumes were measured blind to the diagnoses. As compared to controls, patients had greater volumes in left total OFC (p=0.048) and left lateral OFC (p=0.037). Severity of negative symptoms (anhedonia, flattened affect, and alogia) positively correlated with both the left lateral (Spearman's, rho=0.37, p=0.019; rho=0.317, p=0.041; r=0.307, p=0.048, respectively) and the left total OFC (Spearman's, rho=0.384, p=0.014; rho=0.349, p=0.023; rho=0.309, p=0.047, respectively). The present results suggest that first-episode, antipsychotic-naïve schizophrenia subjects exhibit increased OFC volumes that correlate with negative symptoms severity. The OFC, through extensive and complex interconnections with several brain structures with putative role in pathophysiology of schizophrenia including amygdala, hippocampus, thalamus, DLPFC, and superior temporal lobe, may mediate schizophrenia symptoms such as blunting of emotional affect and impaired social functioning. Although the specific neuropathological mechanisms underlying structural abnormalities of the OFC remain unclear, increased OFC volumes might be related to deviations in neuronal migration and/or pruning. Future follow-up studies examining high-risk individuals who subsequently develop schizophrenia at different stages of disease could be especially instructive.

Longitudinal changes in neuroanatomy and neural activity in early schizophrenia

Although there is substantial evidence indicating that patients with first-episode schizophrenia exhibit both anatomical and electrophysiological abnormalities, there has been little research investigating the relationship between these two indices. We acquired structural magnetic resonance images and resting electroencephalographic recordings from 19 patients with schizophrenia, both at the time of their first presentation to mental health services and 2-3 years subsequently. Patients' grey matter images were parcellated into four brain lobes, and slow-wave, alpha- and beta-electroencephalographic power was calculated in four corresponding cortical regions. Although grey matter volume decreased longitudinally, particularly fronto-parietally, electroencephalographic power increased in the slow-wave and beta-frequency bands. These results suggest that first-episode schizophrenia may be associated with abnormally elevated levels of neural synchrony.

Structural brain abnormalities in early onset first-episode psychosis

BACKGROUND

Brain morphometry in children and adolescents with first-episode psychosis offer a unique opportunity for pathogenetic investigations.

METHODS

We compared high-resolution 3D T1-weighted magnetic resonance images of the brain in 29 patients (schizophrenia, schizotypal disorder, delusional disorder or other non-organic psychosis), aged 10-18 to those of 29 matched controls, using optimized voxel-based morphometry.

RESULTS

Psychotic patients had frontal white matter abnormalities, but expected (regional) gray matter reductions were not observed. Post hoc analyses revealed that schizophrenia patients (n = 15) had significantly larger lateral ventricles as compared to controls. Duration and dose of antipsychotics correlated negatively with global gray matter volume in minimally medicated patients (n = 18).

CONCLUSION

Findings of white matter changes and enlarged lateral ventricles already at illness onset in young schizophrenia spectrum patients, suggests aberrant neurodevelopmental processes in the pathogenesis of these disorders. Gray matter volume changes, however, appear not to be a key feature in early onset first-episode psychosis.

Progressive grey matter atrophy over the first 2-3 years of illness in first-episode schizophrenia: a tensor-based morphometry study

Little is known about the structural brain changes that occur over the first few years of schizophrenia, or how these changes differ from those associated with healthy brain development in adolescence and early adulthood. In this study, we aimed to identify regional differences in grey matter (GM) volume between patients with first-episode schizophrenia (FES) and matched healthy controls, both at the time of the patients' first psychotic episode (baseline condition) and 2-3 years subsequently (follow-up condition). Forty-one patients with FES and 47 matched healthy controls underwent a T1-weighted structural MRI scan. Of these participants, 25 FES patients and 26 controls returned 2-3 years later for a follow-up scan. Voxel-based morphometry in SPM2 was used to identify the regions of GM difference between the groups in the baseline condition, while tensor-based morphometry was used to identify the longitudinal change within subject over the follow-up interval. The FES patients exhibited widespread GM reductions in the frontal, parietal, and temporal cortices and cerebellum in the baseline condition, as well as more circumscribed regions of GM increase, particularly in the occipital lobe. Furthermore, the FES subjects were observed to lose considerably more GM over the follow-up interval than the controls, especially in the parietal and temporal cortices. We argue that the progressive GM atrophy we have found to be associated with the onset of schizophrenia arises from a dysfunction in the dramatic period of healthy brain development typically associated with adolescence.

Grey matter deficits and symptom profile in first episode schizophrenia

Several studies have investigated grey matter reductions in first episode schizophrenia (FES), but few have examined the relationship between grey matter reduction and clinical profile. A group of 31 patients with strictly defined FES and 30 healthy controls underwent T1-weighted magnetic resonance imaging (MRI) scan. Voxel-based morphometry in SPM99 was used to identify four distinct regions of grey matter reduction in the FES subjects. The regions of interest (ROIs) were in the left ventral prefrontal cortex (ROI 1), left parietal and temporal cortices (ROI 2), right cerebellum (ROI 3), and right frontal and parietal cortices (ROI 4). These regions of reduction were transformed into binary masks, which were convolved with patients' pre-processed grey matter images. Patients' grey matter volumes in these regions were correlated with their composite scores on the following three symptom dimensions: Psychomotor Poverty, Disorganization and Reality Distortion. The volumes of ROIs 1, 2 and 4 were found to be significantly correlated with the Reality Distortion syndrome score. Our findings indicate that distinct, widespread grey matter reductions are present very early in the course of schizophrenia. The results also suggest a possible structural underpinning for the abnormal brain activity typically associated with symptoms of Reality Distortion.

Disability in schizophrenia: clinical correlates and prediction over 1-year follow-up

Schizophrenia may cause disability leading to restrictions on many domains of daily life such as hygiene, self-management, vocational and leisure activities, and family and social relationships. The aim of this study was to assess the level of disability with the Brief Disability Questionnaire (BDQ), developed by the World Health Organization, and to identify the clinical correlates and predictors of disability during a 1-year follow-up period in 382 patients with schizophrenia. All patients were assessed at the beginning of the study, and 168 (44%) of them were re-evaluated after 1 year. Total disability scores of the patients with schizophrenia were significantly decreased at follow-up. Female patients seemed to be more disabled than males. Disability showed a positive correlation with the total, positive symptoms and negative symptoms scores on the Brief Psychiatric Rating Scale, as well as scores on the UKU Side Effects Rating Scale. Patients with the disorganized subtype of schizophrenia and residual symptoms were more disabled than patients with other subtype diagnoses. Negative symptoms and duration of untreated psychosis were significant predictors of disability after 1 year. Early-onset schizophrenia had a twofold increased risk for developing disability. Disability in schizophrenia is a clinical phenomenon closely linked to negative symptoms and poor outcome.

A developmental model for similarities and dissimilarities between schizophrenia and bipolar disorder

Schizophrenia and mania have a number of symptoms and epidemiological characteristics in common, and both respond to dopamine blockade. Family, twin and molecular genetic studies suggest that the reason for these similarities may be that the two conditions share certain susceptibility genes. On the other hand, individuals with schizophrenia have more obvious brain structural and neuropsychological abnormalities than those with bipolar disorder; and pre-schizophrenic children are characterised by cognitive and neuromotor impairments, which are not shared by children who later develop bipolar disorder. Furthermore, the risk-increasing effect of obstetric complications has been demonstrated for schizophrenia but not for bipolar disorder. Perinatal complications such as hypoxia are known to result in smaller volume of the amygdala and hippocampus, which have been frequently reported to be reduced in schizophrenia; familial predisposition to schizophrenia is also associated with decreased volume of these structures. We suggest a model to explain the similarities and differences between the disorders and propose that, on a background of shared genetic predisposition to psychosis, schizophrenia, but not bipolar disorder, is subject to additional genes or early insults, which impair neurodevelopment, especially of the medial temporal lobe.

Lower prefrontal gray matter volume in schizophrenia in chronic but not in first episode schizophrenia patients

Although a lower volume of prefrontal (PF) gray matter (GM) in patients with schizophrenia than in normal control subjects is a replicated finding, it is not yet clear whether this finding is present at the onset of illness. Clinical and imaging data suggest that the reduction in PF GM becomes apparent only some years following the onset of illness. To test this hypothesis, we used magnetic resonance imaging to study PF GM and sulcal cerebrospinal fluid (CSF) volumes in 81 schizophrenic patients. A Talairach-based tool was used for segmentation. Subjects included 44 healthy controls, 22 first-episode (FE), treatment-naïve patients with duration of illness of less than 1 year; 29 short-term chronic (SC) patients with durations of illness between 1.5 and 6 years; and 30 long-term chronic (LC) patients with duration of illness of more than 6 years. The data from healthy controls were used to calculate volume residuals in the patients, defined as deviations from the expected values given individual age and intracranial volume. The FE group did not show significant differences in GM or in CSF volumes compared with controls. However, both the SC and the LC patients showed the expected pattern of lower values for PF GM and an excess of PF sulcal CSF compared with controls. There were no significant differences between SC and LC patients in any of these measurements. There was a significant and inverse association between duration of illness and GM residuals. That association fit a nonlinear rather than a linear model, which was consistent with a decrease of GM volume during the first years following illness onset. No significant differences were found between those receiving atypical and typical antipsychotic drugs during the previous year.

Longitudinal assessment of psychopathological domains over late-stage schizophrenia in relation to duration of initially untreated psychosis: 3-year prospective study in a long-term inpatient population

There remains uncertainty regarding any progressive nature of psychopathology and cognitive dysfunction in late-stage schizophrenia, and whether duration of initially untreated psychosis (DUP) might be associated with such 'progression'. This study examines longitudinally, over 3 years, the psychopathology and neuropsychology in 82 inpatients with DSM-IV schizophrenia, many of whom were admitted in the pre-neuroleptic era. Increase in executive dysfunction exceeded that in general cognitive impairment. Positive but not negative symptom severity decreased modestly; the primary predictor of negative symptom severity was DUP. On index assessment, psychopathology evidenced a three-factor structure; at follow-up, psychomotor poverty evidenced greater prominence and cohesion, and was on both occasions predicted primarily by DUP, while reality distortion was altered and disorganisation disassembled into alternative elements. It would appear that as years of chronic, refractory illness accrue, psychomotor poverty becomes more sharply delineated and dominant within the overall structure of psychopathology, and its prominence is predicted enduringly by DUP.

The role of age in the development of Schneiderian symptoms in patients with a first psychotic episode

OBJECTIVE

The likelihood of developing psychotic symptoms greatly increases after puberty. In acute psychotic disorders, first rank symptoms (FRS) are prevalent and considered useful for the diagnostic process. The aim of this study was to test for a linear association between age and the probability of occurrence of FRS in patients with a first psychotic episode (FPE).

METHOD

A total of 112 patients, consecutively admitted with an FPE, were included at baseline and evaluated yearly over a 3-year period using SCID-I and a checklist of 11 items of FRS.

RESULTS

FRS were documented for 65.2% patients at baseline. There was a dose-response relationship in the association between age and FRS. There was no interaction with sex or with final diagnostic category.

CONCLUSION

Variation in the expression of the core positive symptoms of psychosis is subject to the influence of underlying age-dependent maturational processes both in terms of occurrence and level of severity.

Randomized trial of olanzapine versus placebo in the symptomatic acute treatment of the schizophrenic prodrome

BACKGROUND

The prodromal phase of schizophrenic disorders has been described prospectively. The present study aimed to determine the short-term efficacy and safety of olanzapine treatment of prodromal symptoms compared with placebo.

METHODS

This was a double-blind, randomized, parallel-groups, placebo-controlled trial with fixed-flexible dosing conducted at four sites. Sixty patients met prodromal diagnostic criteria, including attenuated psychotic symptoms, as determined by structured interviews. Olanzapine 5-15 mg daily or placebo was prescribed for 8 weeks.

RESULTS

In the mixed-effects, repeated-measures analysis, the treatment x time interaction for the change from baseline on the Scale of Prodromal Symptoms total score was statistically significant, and post hoc analyses revealed that the olanzapine-placebo difference reached p<.10 by week 6 and p<.05 at week 8. Ratings of extrapyramidal symptoms remained low in each group and were not significantly different. Olanzapine patients gained 9.9 lb versus.7 lb for placebo patients (p<.001).

CONCLUSIONS

This short-term analysis suggests olanzapine is associated with significantly greater symptomatic improvement but significantly greater weight gain than is placebo in prodromal patients. Extrapyramidal symptoms with olanzapine were minimal and similar to those with placebo. Future research over the longer term with more patients will be needed before recommendations can be made regarding routine treatment.

Does schizophrenia result from developmental or degenerative processes?

The debate as to whether schizophrenia is a neurodevelopmental or a neurodegenerative disorder has its roots in the latter part of the 19th century when authorities such as Clouston (1891) posited that at least some insanities were "developmental" in origin. These views were soon eclipsed by Kraepelin's (1896) concept of dementia praecox as a degenerative disease, and the latter view carried not only the day but also much of the 20th century. Then, in the 1980s several research groups again began to speculate that schizophrenia might have a significant developmental component (Feinberg, 1982-1983; Schulsinger et al., 1984; Murray et al., 1985; Murray and Lewis, 1987; Weinberger et al., 1987). What became known as the "neurodevelopmental hypothesis" received support from neuropathological studies implicating anomalies in early brain development such as aberrant migration of neurons. Unfortunately, these studies proved difficult, if not impossible, to replicate (Harrison, 1999). The pendulum, therefore, began to swing again, and in the latter part of the 1990s came renewed claims that the clinical progression of the illness was accompanied by continued cerebral ventricular enlargement and reduction in the volumes of certain brain structures. Nevertheless, since few doubt that there is a developmental component to schizophrenia, the question which we will address in this paper is whether schizophrenia is a) simply the final consequence of a cascade of increasing developmental deviance (Bramon et al., 2001), or b) whether there is an additional brain degeneration following onset of psychosis which is superimposed on the developmental impairment (Lieberman, 1999).

The early stages of schizophrenia: speculations on pathogenesis, pathophysiology, and therapeutic approaches

Schizophrenia is commonly considered a neurodevelopmental disorder that is associated with significant morbidity; however, unlike other neurodevelopmental disorders, the symptoms of schizophrenia often do not manifest for decades. In most patients, the formal onset of schizophrenia is preceded by prodromal symptoms, including positive symptoms, mood symptoms, cognitive symptoms, and social withdrawal. The proximal events that trigger the formal onset of schizophrenia are not clear but may include developmental biological events and environmental interactions or stressors. Treatment with antipsychotic drugs clearly ameliorates psychotic symptoms, and maintenance therapy may prevent the occurrence of relapse. The use of atypical antipsychotic agents may additionally ameliorate the pathophysiology of schizophrenia and prevent disease progression. Moreover, if treated properly early in the course of illness, many patients can experience a significant remission of their symptoms and are capable of a high level of recovery following the initial episode. Because the clinical deterioration that occurs in schizophrenia may actually begin in the prepsychotic phase, early identification and intervention may favorably alter the course and outcome of schizophrenia.

A longitudinal study of hippocampal volume in first episode psychosis and chronic schizophrenia

Brain abnormalities have been identified in patients with schizophrenia, but what is unclear is whether these changes are progressive over the course of the disorder. In this longitudinal study, hippocampal and temporal lobe volumes were measured at two time points in 30 patients with first episode psychosis (mean follow-up interval=1.9 years, range 0.54-4.18 years) and 12 with chronic schizophrenia (mean follow-up interval=2.3 years, range 1.03-4.12 years) and compared to 26 comparison subjects (mean follow-up interval 2.2 years, range 0.86-4.18 years). Hippocampal, temporal lobe, whole-brain and intracranial volumes (ICV) were estimated from high-resolution magnetic resonance images. Only whole-brain volume showed significant loss over the follow-up interval in both patient groups. The rate of this volume loss was not different in the first episode group compared to the chronic group. There were no changes in either hippocampal or temporal lobe volumes. The negative findings for the hippocampus and temporal lobes may mean that the abnormalities in these regions are stable features of schizophrenia. Alternatively, the period before the onset of frank psychotic symptoms may be the point of greatest risk for progressive change.

The origin and course of schizophrenia: implications for clinical practice

The authors first review current evidence concerning abnormalities of brain structure and function in schizophrenia and interpret them within a "network" pathophysiological model of the disorder. This information is then placed within a contemporary neurodevelopmental framework that "roots" the illness in adverse events during early pregnancy, which result in a developmentally compromised nervous system. They then consider the controversy as to whether the subsequent expression of psychosis reflects an active morbid process and, in a more general sense, whether the disorder is characterized by subsequent progression and clinical deterioration. The authors argue that the developmental and progressive models should not be considered in an either-or manner, since this perspective is not logical and favors nihilistic approaches to intervention and treatment, but rather should be integrated within a lifetime trajectory model. Finally, implications for current psychiatric practice are considered.

Schizophrenia and liver dysfunction

It is suggested that a non-hepatocellular liver dysfunction, caused by the presence of a congenital or acquired portal-systemic shunt, constitutes a major predisposing factor in the pathogenesis of schizophrenia. In addition to the common occurrence of schizophrenic reactions observed in liver disease, this suggestion is supported by autoptic findings in addition to the fact that a considerable number of abnormal biochemical and biological phenomena are shared by patients suffering from schizophrenia and portal-systemic shunting. The frequency of abnormal portal-systemic shunts in schizophrenia is unknown. Recent advances in non-invasive Doppler-sonographic techniques should enable an elucidation of this question.

Evidence for progression of brain structural abnormalities in schizophrenia: beyond the neurodevelopmental model

OBJECTIVE

Clinical, neuroimaging, neuropathological and neuropsychological evidence suggests that, in schizophrenia, there is structural and functional disturbance of the hippocampus. The purpose of this paper is to present published findings concerning the nature, timing and course of these putative disturbances of hippocampal function and the pathophysiological mechanisms involved, and to explore whether schizophrenia is a disorder of neurodevelopment, neurodegeneration or a combination of both processes.

METHOD

The available cross-sectional and longitudinal evidence for hippocampal involvement in schizophrenia is reviewed and a model of hippocampal involvement in this disorder, which derives from our own cross-sectional and longitudinal hippocampal imaging data, is described.

RESULTS

We propose a three-hit model in which an early neurodevelopmental lesion renders the hippocampus vulnerable to further insult later in life during the transition phase to active illness. The available evidence suggests that the left hippocampus is particularly vulnerable during these early stages, while further insult involving the hippocampus bilaterally occurs in those who develop a chronic form of the illness.

CONCLUSIONS

Intervention strategies should target the most vulnerable stages of the illness, in particular the transition phase to psychosis, when novel treatments may prevent the illness or ameliorate its effects.