Duration of illness and structure of symptoms in schizophrenia

M. Staging of Schizophrenia With the Use of PANSS: An International Multi-Center Study

INTRODUCTION

A specific clinically relevant staging model for schizophrenia has not yet been developed. The aim of the current study was to evaluate the factor structure of the PANSS and develop such a staging method.

METHODS

Twenty-nine centers from 25 countries contributed 2358 patients aged 37.21 ± 11.87 years with schizophrenia. Analysis of covariance, Exploratory Factor Analysis, Discriminant Function Analysis, and inspection of resultant plots were performed.

RESULTS

Exploratory Factor Analysis returned 5 factors explaining 59% of the variance (positive, negative, excitement/hostility, depression/anxiety, and neurocognition). The staging model included 4 main stages with substages that were predominantly characterized by a single domain of symptoms (stage 1: positive; stages 2a and 2b: excitement/hostility; stage 3a and 3b: depression/anxiety; stage 4a and 4b: neurocognition). There were no differences between sexes. The Discriminant Function Analysis developed an algorithm that correctly classified >85% of patients.

DISCUSSION

This study elaborates a 5-factor solution and a clinical staging method for patients with schizophrenia. It is the largest study to address these issues among patients who are more likely to remain affiliated with mental health services for prolonged periods of time.

Mismatch negativity-indexed auditory change detection of speech sounds in early and chronic schizophrenia

Auditory change detection, as indexed by the EEG-derived mismatch negativity, has been demonstrated to be dysfunctional in chronic schizophrenia using both pure-tone and speech (phoneme) sounds. It is unclear, however, whether reduced MMN amplitudes to speech sound deviants are observed within the first 5 years of the illness. The present study investigated MMNs elicited by across-vowel (phoneme) change in early schizophrenia (ESZ; Experiment 1) as well as chronic schizophrenia (CSZ; Experiment 2). In both experiments, clinical and control participants were presented the Finnish phoneme /e/ (standard; P = .90) and the Finnish phoneme /ö/ (deviant; P = .10) within an oddball paradigm. In experiment 2 we report significantly reduced MMN amplitudes in CSZ relative to HCs, but no differences were found when comparing ESZ and HC in experiment 1. Additionally, in our clinical samples, MMN amplitudes were correlated with symptom scores. These findings suggest that early detection of phonetic change may be impaired in chronic schizophrenia, but not early in the progression of the illness. As MMN reductions only emerged in patients with a longer course of illness, and appeared to change with symptom severity, this suggests a dynamic change in the early auditory processing of language over time in schizophrenia.

Methodology and reporting of systematic reviews and meta-analyses of observational studies in psychiatric epidemiology: systematic review

BACKGROUND

Relatively little is known of the use of systematic review and synthesis methods of non-randomised psychiatric epidemiological studies, which play a vital role in aetiological research, planning and policy-making.

AIMS

To evaluate reviews of psychiatric epidemiological studies of functional mental disorders that employed synthesis methods such as systematic review or meta-analysis, or other forms of quantitative review.

METHOD

We searched the literature to identify appropriate reviews published during the period 1996 to April 2009. Selected reviews were evaluated using published review guidelines.

RESULTS

We found 106 reviews in total, of which 38 (36%) did not mention method of data abstraction from primary studies at all. Many failed to mention study quality, publication bias, bias and confounding. In 73 studies that performed a meta-analysis, 58 (79%) tested for heterogeneity and of these, 47 found significant heterogeneity. Studies that detected heterogeneity made some allowance for this. A major obstacle facing reviewers is the wide variation between primary studies in the use of instruments to measure outcomes and in sampling methods used.

CONCLUSIONS

Many deficiencies found in systematic reviews are potentially remediable, although synthesis of primary study findings in a field characterised by so many sources of heterogeneity will remain challenging.

HTR2A A-1438G/T102C polymorphisms predict negative symptoms performance upon aripiprazole treatment in schizophrenic patients

RATIONALE

Aripiprazole acts as a partial agonist at dopamine D2 and D3 and serotonin 1A receptors and as an antagonist at serotonin 2A receptors (HTR2A). Since aripiprazole acts as an antagonist at HTR2A, genetic variants of HTR2A may be important in explaining variability in response to aripiprazole.

OBJECTIVES

This study investigated whether the efficacy of aripiprazole can be predicted by functional HTR2A A-1438G/T102C polymorphisms (rs63311/rs6313) as modified by clinical factors in Han Chinese hospitalized patients with acutely exacerbated schizophrenia.

MATERIALS AND METHODS

After hospitalization, the patients (n = 128) were given a 4-week course of aripiprazole. Patients were genotyped for HTR2A A-1438G/T102C polymorphisms via the restriction fragment length polymorphism method. Clinical factors such as gender, age, duration of illness, education level, diagnostic subtype, and medication dosage were noted as well. The researchers measured psychopathology biweekly, using the Positive and Negative Syndrome Scale (PANSS). A mixed model regression approach (SAS Proc MIXED) was used to analyze the effects of genetic and clinical factors on PANSS performance after aripiprazole treatment.

RESULTS

We found that the GG/CC genotype group of HTR2A A-1438G/T102C polymorphisms predicts poor aripiprazole response specifically for negative symptoms. In addition, the clinical factors, including dosage of aripiprazole, age, duration of illness, and diagnostic subtype, were found to influence PANSS performance after aripiprazole treatment.

CONCLUSIONS

The data suggest HTR2A A-1438G/T102C polymorphisms may predict negative symptoms performance upon aripiprazole treatment in schizophrenic patients as modified by clinical factors.

Causal model of insight and psychopathology based on the PANSS factors: 1-year cross-sectional and longitudinal revalidation

This study presents results of a 1-year follow-up investigation of the causal model of insight in schizophrenia using a subsample of acute patients starting or switching to amisulpride included in an earlier study. Our causal model of insight based on the Positive and Negative Syndrome Scale factors, with the positive, negative, and autistic preoccupation factors designated as the primary predictors, and the activation factor as a mediating variable of insight, was examined for fitness at the stabilized stage (8 week) and at the chronic stage (1 year) using the structural equation modeling method. Results showed that the intercorrelations among the factors and regression coefficients toward insight changed in their magnitudes, but the validity of our hypothesized model of insight was still confirmed for both the stages with nearly perfect goodness-of-fitness indices. The fitness of the model was also confirmed for the longitudinal changes in the scores of insight and psychopathology. An alternative model, which included the anxiety/depressive factor as a second mediating variable between insight and the positive and negative factors, was also found to be valid for both the stages. A post-hoc causal model with anxiety/depressive factor showed tentative evidence favoring anxiety/depressive variable predicting insight than the other way around.

Effects of the DRD3 Ser9Gly polymorphism on aripiprazole efficacy in schizophrenic patients as modified by clinical factors

Aripiprazole, a novel antipsychotic agent, has a unique pharmacological action (partial agonist) on the dopamine neurotransmission system. Aripiprazole has high affinity for dopamine D2 and D3 receptors (DRD2 and DRD3). We investigated whether the efficacy of aripiprazole can be predicted by a functional DRD3 gene polymorphism Ser9Gly (rs6280) as modified by clinical factors in Han Chinese hospitalized patients with acutely exacerbated schizophrenia. After hospitalization, the patients (n=128) were given aripiprazole for up to four weeks. Patients were genotyped for DRD3 Ser9Gly polymorphism by Restriction Fragment Length Polymorphism (RFLP) method. Clinical factors such as gender, age, duration of illness, education level, diagnostic subtype and medication dosage were recorded. Psychopathology was measured biweekly with the Positive and Negative Syndrome Scale (PANSS). The effects of genetic and clinical factors on PANSS performance after aripiprazole treatment were analyzed by a mixed model regression approach (SAS Proc MIXED). We found that, although the Ser carriers have numerically larger score reductions when compared with non-carriers in almost all PANSS dimensions, the difference of their effects are statically not significant. However, the clinical factors, including dosage of aripiprazole, age, duration of illness, and diagnostic subtype could influence PANSS performance after aripiprazole treatment. This study suggests that DRD3 Ser9Gly polymorphism may not contribute significantly to inter-individual differences in therapeutic efficacy of aripiprazole, but some clinical factors may predict treatment efficacy.

Effects of DRD2/ANKK1 gene variations and clinical factors on aripiprazole efficacy in schizophrenic patients

OBJECTIVES

Aripiprazole, a novel antipsychotic agent, acts as a partial agonist at dopamine D2 receptors (DRD2). We investigate whether its efficacy is predictable by DRD2/ANKK1 gene polymorphisms and clinical factors in Han Chinese hospitalized patients with acutely exacerbated schizophrenia.

METHOD

After hospitalization, the patients (n=128) were given aripiprazole for up to 4 weeks. They were genotyped for four functional DRD2/ANKK1 polymorphisms: -141 Ins/Del, Ser311Cys, C957T, and TaqIA. Clinical factors such as gender, age, illness duration, education level, diagnostic subtype, and medication dosage were also recorded. Psychopathology was measured biweekly with the positive and negative syndrome scale (PANSS). The effects of genetic and clinical factors on PANSS performance upon aripiprazole treatment were analyzed by a mixed modeling approach (SAS Proc MIXED).

RESULTS

Compared to the patients with TaqI A2/A2 genotype, A1 carriers are associated with superior therapeutic response on positive symptoms after 4-week aripiprazole treatment. Regarding the C957T polymorphism, patients with C/C genotype were associated with poor aripiprazole response for excitement symptoms when compared with T/T patients. The other two polymorphisms, -141 Ins/Del, and Ser311Cys, have no significant effects on PANSS performance. The clinical factors including medication dosage, illness duration, and diagnostic subtype could influence PANSS performance upon aripiprazole treatment.

CONCLUSION

This study suggests that DRD2/ANKK1 gene variations and some clinical factors may predict individual response to aripiprazole.

Familiality in a five-factor model of schizophrenia psychopathology: findings from a 16-month follow-up study

We sought to examine stability associations between family history and variability of schizophrenia symptoms repeatedly examined during a naturalistic follow-up study. The Positive and Negative Syndrome Scale, the Insight and Treatment Attitudes Questionnaire, and the Abnormal Involuntary Movement Scale were administered to 69 patients with familial and 79 patients with sporadic schizophrenia, at hospital admission and at stabilization stage (about 16 months later). Analysis of covariance was applied to identify the association of symptom factors with familiality of schizophrenia. We found that schizophrenia patients with positive family histories had significantly higher dysphoric, activation and negative factors. However, familiality of activation and negative factors were dependent on additional variables such as age of onset (both factors), baseline ratings, insight, and side effects (negative factor). No significant association of family history with intensity of positive and autistic preoccupation factors was found. Familial schizophrenia is characterized by higher severity of dysphoric mood factors that may represent impaired emotional reactivity. It is suggested that dysphoric mood may be a useful phenotype for molecular genetic studies of schizophrenia with positive family history.

Anxiety and schizophrenia: the interaction of subtypes of anxiety and psychotic symptoms

OBJECTIVE

To examine the interaction of specific anxiety subtypes and psychosis.

INTRODUCTION

Accumulating evidence suggests that anxiety and its disorders play a significant role in patients with schizophrenia, but few studies have examined multiple types of anxiety and how they interact with different symptoms of schizophrenia.

METHODS

Thirty-two patients diagnosed with schizophrenia or schizoaffective disorder were assessed through self-report measures and interviewer rating scales to examine symptoms of psychosis and anxiety.

RESULTS

A majority of patients (62%) were diagnosed with at least one comorbid anxiety disorder. Obsessive-compulsive symptoms and social anxiety symptoms were related to positive symptoms, bizarre behavior, and quality of life (QOL). Furthermore, panic and social anxiety were related to suspiciousness/paranoia. No consistent relationship was found with negative symptoms. Finally, severity of anxiety disorders was negatively correlated with the severity of formal thought disorder.

DISCUSSION

This is one of the first studies to simultaneously examine the interrelationships of different types of anxiety symptoms and psychotic symptoms. The present findings are consistent with the studies that have suggested relationships between panic and paranoia and comorbid anxiety disorders and impaired QOL. These data suggest that further research into anxiety in schizophrenia, including the cognitive and neurobiological correlates, may help elucidate the mechanisms involved in the manifestation of these psychopathologies.

CONCLUSION

Anxiety disorders are common in patients with schizophrenia. The presence of such symptoms may influence the presence of core psychotic symptoms and QOL. More information is needed in terms of the relationship between treatment of these symptoms and changes in psychotic symptoms and/or relapse prevention.

The relationships between symptom dimensions and dysphoria in schizophrenia

Previous studies have suggested that qualitatively distinct aspects of dysphoria (anxiety and depression) are related to specific dimension of schizophrenia symptomatology. Most of these studies used simple dimensions and dysphoria models, although finer distinctions could help defining specific relationships. This study examined the relationships of distinctive aspects of depression and anxiety (both state and trait) with symptom dimensions. Forty patients with a DSM-IV diagnosis of schizophrenia were assessed for symptoms (SAPS-SANS), trait and state anxiety (STAI) and depression (CDS). Symptoms ratings were summarized as dimensional scores according to a two-, three- or five-dimensional models proposed in the literature. The correlation analysis replicates previous observations that distinct aspects of dysphoria are associated with specific dimensions of schizophrenia, with the exception of disorganization. Moreover, controlling for intercorrelated variables revealed that schizophrenia and dysphoric symptoms might act in combination and/or through indirect links to contribute to illness expression. Our data further suggested that these associations may be best understood in terms of interactions between various processing biases alluded in the most recent cognitive accounts of schizophrenia symptoms.

The timing of negative symptom exacerbations in relationship to positive symptom exacerbations in the early course of schizophrenia

Although positive and negative symptoms appear to represent independent symptom dimensions of psychopathology when evaluated cross-sectionally among individuals with schizophrenia, it is not known if exacerbations of symptoms on these two dimensions are independent. This prospective longitudinal study examined the temporal relationship between the positive and negative symptom exacerbations among 48 recent-onset schizophrenia or schizoaffective patients who received symptom ratings every 2 weeks on the Brief Psychiatric Rating Scale. Patients were followed for a period of at least 1 year and a mean of 3 years. To examine the temporal relationship between positive and negative symptoms, six time periods were defined in relation to psychotic exacerbation or relapse (e.g., prodromal, concurrent, post-psychotic) and used to compare the timing of positive and negative symptom exacerbations. A substantial proportion of patients had exacerbations of positive symptoms (77%) and negative (42%) symptoms. Negative symptom exacerbations occurred simultaneously with positive symptom exacerbations to a significantly greater extent than expected by chance, and occurred less frequently than expected by chance during the time period most temporally removed from positive symptom exacerbations. Results suggest that the timing of some negative symptom exacerbations is linked to that of positive symptom exacerbations during the early course of schizophrenia.

Patterns of symptoms in neuroleptic-naive patients with schizophrenia and related psychotic disorders before and after treatment

A three-factor structure of schizophrenic symptoms has received considerable support, but there are no data on the factor structure of symptoms in neuroleptic-naive patients and how symptoms evolve after the inception of antipsychotic treatment. Seventy neuroleptic-naive patients with schizophrenia or related psychotic disorders were assessed with the Scales for the Assessment of Positive and Negative Symptoms before and after neuroleptic treatment. Ten global ratings of symptoms were subjected to factor analysis at the two time points and the factor solutions compared. A three-factor structure composed of psychotic, disorganization, and negative dimensions was found at the two assessment points. The negative and disorganization factors were highly correlated at each assessment and across assessments. While the symptom composition of the factors at the neuroleptic-naive assessment fitted that described in most previous studies, the composition of the negative and disorganization factors after neuroleptic treatment was somewhat different in that attention and inappropriate affect loaded on the negative factor instead of the disorganization factor. It is concluded that caution is warranted when using the three-factor model of schizophrenic symptoms as it may not be stable at different phases of the illness.

Integrating psychopathological dimensions in functional psychoses: a hierarchical approach

Previous factor analysis studies of psychotic symptomatology have demonstrated three psychopathological dimensions: positive, negative and disorganization. However, few studies have analyzed non-schizophrenic samples and most use a syndrome-level of analysis or only schizophrenic symptom scales. This study examined how many dimensions underlie psychosis, and whether within psychosis there is a hierarchical organization of dimensions.A total of 660 inpatients with an acute psychotic episode were studied. Psychopathology was measured through a wide psychopathological assessment using the Manual for the Assessment and Documentation of Psychopathology (AMDP-system). Principal component factor analysis was carried out on 64 psychopathological symptoms scoring 1 or higher in at least 10% of the sample. A 15-factor solution was obtained which failed to depict a psychosis model on clinical and methodological grounds. Further predetermined factor analyses ranging from 1 to 15 factors were carried out to examine alternative factor solutions. A 10-dimensional model was the best model on clinical, statistical and conceptual grounds. Moreover, the examination of the 1 to 10 dimensional models allowed us to infer a hierarchical model of psychopathological dimensions, which can be represented in the frame of a tree-structure. The model permitted transitions between psychiatric categories and psychopathological dimensions, and it was able to integrate previous factor solutions with different numbers of resulting dimensions.The findings have implications for the design of future studies and for the hierarchical conceptualization of psychopathological dimensions.

How many and which are the psychopathological dimensions in schizophrenia? Issues influencing their ascertainment

During the last two decades, much effort has been made to precisely characterize the symptom dimensions of schizophrenia. A number of dimensional models have been proposed, the most popular of which has been a three-dimensional model consisting of psychotic, negative and disorganizational symptoms. This model, however, has been criticized as too simplistic, and more complex models have been proposed, although to date there has been no consensus as to the number and nature of dimensions necessary to account for the whole range of schizophrenic symptoms. In the present paper, the authors review the main methodological issues which have led to the current confusion about the number of dimensions underlying schizophrenic psychopathology. Among the main issues influencing the delimitation of dimensions are: statistical procedures for determining the number of factors, phase of the illness, level of analysis of symptoms (i.e., symptoms or groups of symptoms), and measurement instrument used. Studies analyzing either a broad range of symptoms or particular symptoms at a finer level have produced a rather complex picture of schizophrenic dimensions. There is evidence supporting the existence of eight major dimensions of psychopathology: psychosis, disorganization, negative, mania, depression, excitement, catatonia and lack of insight. The dimensional structure of symptoms becomes even more complex if one considers that these big dimensions can be further divided into more elementary components. A hierarchical approach for organizing the complex dimensional structure of schizophrenic symptoms is proposed.

Reappraisal of Dementia Praecox: focus on clinical psychopathology

One century of investigation in schizophrenia is still not enough to elucidate all the complex issues related to the essential symptomatology, clinical boundaries, aetiology, pathogenesis, outcome, treatment and prevention. Despite the extraordinary progress in the neuroscience field, no definitive data is available for schizophrenia. On the other hand, after the successful activity of the psychopharmacological era, the clinical psychopathological investigations were reduced and almost replaced by the mechanistic operational diagnosis. This has caused an impoverishment in psychiatry. Tracing some historical aspects of schizophrenia since the kraepelinian Dementia Praecox, this article intends to demonstrate the failure of the current model of diagnosis and current limitation of neuroscience. It advocates the reinforcement of Clinical Psychopathology as the foundation for correct and appropriate first steps in the investigation of schizophrenia. The splitting disease is still a challenge to biological psychiatry.