Integrating psychopathological dimensions in functional psychoses: a hierarchical approach

A transdiagnostic prodrome for severe mental disorders: an electronic health record study

Effective prevention of severe mental disorders (SMD), including non-psychotic unipolar mood disorders (UMD), non-psychotic bipolar mood disorders (BMD), and psychotic disorders (PSY), rely on accurate knowledge of the duration, first presentation, time course and transdiagnosticity of their prodromal stages. Here we present a retrospective, real-world, cohort study using electronic health records, adhering to RECORD guidelines. Natural language processing algorithms were used to extract monthly occurrences of 65 prodromal features (symptoms and substance use), grouped into eight prodromal clusters. The duration, first presentation, and transdiagnosticity of the prodrome were compared between SMD groups with one-way ANOVA, Cohen's f and d. The time course (mean occurrences) of prodromal clusters was compared between SMD groups with linear mixed-effects models. 26,975 individuals diagnosed with ICD-10 SMD were followed up for up to 12 years (UMD = 13,422; BMD = 2506; PSY = 11,047; median[IQR] age 39.8[23.7] years; 55% female; 52% white). The duration of the UMD prodrome (18[36] months) was shorter than BMD (26[35], d = 0.21) and PSY (24[38], d = 0.18). Most individuals presented with multiple first prodromal clusters, with the most common being non-specific ('other'; 88% UMD, 85% BMD, 78% PSY). The only first prodromal cluster that showed a medium-sized difference between the three SMD groups was positive symptoms (f = 0.30). Time course analysis showed an increase in prodromal cluster occurrences approaching SMD onset. Feature occurrence across the prodromal period showed small/negligible differences between SMD groups, suggesting that most features are transdiagnostic, except for positive symptoms (e.g. paranoia, f = 0.40). Taken together, our findings show minimal differences in the duration and first presentation of the SMD prodromes as recorded in secondary mental health care. All the prodromal clusters intensified as individuals approached SMD onset, and all the prodromal features other than positive symptoms are transdiagnostic. These results support proposals to develop transdiagnostic preventive services for affective and psychotic disorders detected in secondary mental healthcare.

Psychosis superspectrum I: Nosology, etiology, and lifespan development

This review describes the Hierarchical Taxonomy of Psychopathology (HiTOP) model of psychosis-related psychopathology, the psychosis superspectrum. The HiTOP psychosis superspectrum was developed to address shortcomings of traditional diagnoses for psychotic disorders and related conditions including low reliability, arbitrary boundaries between psychopathology and normality, high symptom co-occurrence, and heterogeneity within diagnostic categories. The psychosis superspectrum is a transdiagnostic dimensional model comprising two spectra-psychoticism and detachment-which are in turn broken down into fourteen narrow components, and two auxiliary domains-cognition and functional impairment. The structure of the spectra and their components are shown to parallel the genetic structure of psychosis and related traits. Psychoticism and detachment have distinct patterns of association with urbanicity, migrant and ethnic minority status, childhood adversity, and cannabis use. The superspectrum also provides a useful model for describing the emergence and course of psychosis, as components of the superspectrum are relatively stable over time. Changes in psychoticism predict the onset of psychosis-related psychopathology, whereas changes in detachment and cognition define later course. Implications of the superspectrum for genetic, socio-environmental, and longitudinal research are discussed. A companion review focuses on neurobiology, treatment response, and clinical utility of the superspectrum, and future research directions.

Psychopathological networks in psychosis: Changes over time and clinical relevance. A long-term cohort study of first-episode psychosis

BACKGROUND

First-episode psychosis is a critical period for early interventions to reduce the risk of poor outcomes and relapse as much as possible. However, uncertainties about the long-term outcomes of symptomatology remain to be ascertained.

METHODS

The aim of the present study was to use network analysis to investigate first-episode and long-term stages of psychosis at three levels of analysis: micro, meso and macro. The sample was a cohort of 510 patients with first-episode psychoses from the SEGPEP study, who were reassessed at the long-term follow-up (n = 243). We used the Comprehensive Assessment of Symptoms and History for their assessments and lifetime outcome variables of clinical relevance.

RESULTS

Our results showed a similar pattern of clustering between first episodes and long-term follow-up in seven psychopathological dimensions at the micro level, 3 and 4 dimensions at the meso level, and one at the macro level. They also revealed significant differences between first-episode and long-term network structure and centrality measures at the three levels, showing that disorganization symptoms have more influence in long-term stabilized patients.

CONCLUSIONS

Our findings suggest a relative clustering invariance at all levels, with the presence of two domains of disorganization as the most notorious difference over time at micro level. The severity of disorganization at the follow-up was associated with a more severe course of the psychosis. Moreover, a relative stability in global strength of the interconnections was found, even though the network structure varied significantly in the long-term follow-up. The macro level was helpful in the integration of all dimensions into a common psychopathology factor, and in unveiling the strong relationships of psychopathological dimensions with lifetime outcomes, such as negative with poor functioning, disorganization with high antipsychotic dose-years, and delusions with poor adherence to treatment. These results add evidence to the hierarchical, dimensional and longitudinal structure of psychopathological symptoms and their clinical relevance in first-episode psychoses.

Affective symptom dimensions in early-onset psychosis over time: a principal component factor analysis of the Young Mania Rating Scale and the Hamilton Depression Rating Scale

Early-onset psychosis (EOP) is a complex disorder characterized by a wide range of symptoms, including affective symptoms. Our aim was to (1) examine the dimensional structure of affective symptoms in EOP, (2) evaluate the predominance of the clinical dimensions and (3) assess the progression of the clinical dimensions over a 2-year period. STROBE-compliant prospective principal component factor analysis of Young Mania Rating Scale (YMRS) and Hamilton Depression Rating Scale-21 (HDRS-21) at baseline, 6-months, 1-year and 2-year follow-up. We included 108 EOP individuals (mean age = 15.5 ± 1.8 years, 68.5% male). The factor analysis produced a four-factor model including the following dimensions: mania, depression/anxiety, sleep and psychosis. It explained 47.4% of the total variance at baseline, 60.6% of the total variance at 6-months follow-up, 54.5% of the total variance at 1-year follow-up and 49.5% of the total variance at 2-year follow-up. According to the variance explained, the mania factor was predominant at baseline (17.4%), 6-month follow-up (23.5%) and 2-year follow-up (26.1%), while the depression/anxiety factor was predominant at 1-year follow-up (23.1%). The mania factor was the most stable; 58.3% items that appeared in this factor (with a load > 0.4) at any time point appeared in the same factor at ≥ 3/4 time points. Affective symptoms are frequent and persistent in EOP. Mania seems to be the most predominant and stable affective dimension. However, depression and anxiety may gain predominance with time. A comprehensive evaluation of the dimensional structure and the progression of affective symptoms may offer clinical and therapeutic advantages.

The association between benzodiazepine use and greater risk of neurocognitive impairment is moderated by medical burden in people with HIV

Benzodiazepine use is linked to neurocognitive impairment (NCI) in the general population and people with HIV (PWH); however, this relationship may depend on age-related factors such as medical comorbidities, which occur at an elevated rate and manifest earlier in PWH. We retrospectively examined whether chronological age or medical burden, a clinical marker for aging, moderated the relationship between benzodiazepine use and NCI in PWH. Participants were 435 PWH on antiretroviral therapy who underwent neurocognitive and medical evaluations, including self-reported current benzodiazepine use. A medical burden index score (proportion of accumulated multisystem deficits) was calculated from 28 medical deficits. Demographically corrected cognitive deficit scores from 15 neuropsychological tests were used to calculate global and domain-specific NCI based on established cut-offs. Logistic regressions separately modeled global and domain-specific NCI as a function of benzodiazepine x age and benzodiazepine x medical burden interactions, adjusting for current affective symptoms and HIV disease characteristics. A statistically significant benzodiazepine x medical burden interaction (p = .006) revealed that current benzodiazepine use increased odds of global NCI only among those who had a high medical burden (index score > 0.3 as indicated by the Johnson–Neyman analysis), which was driven by the domains of processing speed, motor, and verbal fluency. No age x benzodiazepine interactive effects on NCI were present. Findings suggest that the relationship between BZD use and NCI among PWH is specific to those with greater medical burden, which may be a greater risk factor for BZD-related NCI than chronological age.

Predicting Long-Term Outcomes in First-Admission Psychosis: Does the Hierarchical Taxonomy of Psychopathology Aid DSM in Prognostication?

The Hierarchical Taxonomy of Psychopathology (HiTOP) is an empirical, dimensional model of psychological symptoms and functioning. Its goals are to augment the use and address the limitations of traditional diagnoses, such as arbitrary thresholds of severity, within-disorder heterogeneity, and low reliability. HiTOP has made inroads to addressing these problems, but its prognostic validity is uncertain. The present study sought to test the prediction of long-term outcomes in psychotic disorders was improved when the HiTOP dimensional approach was considered along with traditional (ie, DSM) diagnoses. We analyzed data from the Suffolk County Mental Health Project (N = 316), an epidemiologic study of a first-admission psychosis cohort followed for 20 years. We compared 5 diagnostic groups (schizophrenia/schizoaffective, bipolar disorder with psychosis, major depressive disorder with psychosis, substance-induced psychosis, and other psychoses) and 5 dimensions derived from the HiTOP thought disorder spectrum (reality distortion, disorganization, inexpressivity, avolition, and functional impairment). Both nosologies predicted a significant amount of variance in most outcomes. However, except for cognitive functioning, HiTOP showed consistently greater predictive power across outcomes-it explained 1.7-fold more variance than diagnoses in psychiatric and physical health outcomes, 2.1-fold more variance in community functioning, and 3.4-fold more variance in neural responses. Even when controlling for diagnosis, HiTOP dimensions incrementally predicted almost all outcomes. These findings support a shift away from the exclusive use of categorical diagnoses and toward the incorporation of HiTOP dimensions for better prognostication and linkage with neurobiology.

[Depression in the structure of schizophrenia: clinical and biochemical characteristics]

THE AIM OF THE STUDY

Was to investigate clinical and biochemical correlates of depression in the structure of schizophrenia to improve its diagnosis and differential diagnosis and to deepen understanding of mechanisms of schizophrenia development. Material and Methods. Forty-two inpatients at the stabilization stage of paranoid schizophrenia, aged 29.5±5.9 years, of whom 64.3% were women, were examined. The duration of the disease was 5.6±6.3 years. We used clinical and psychopathological methods, clinical scales (PANSS, SANS, BACS, Calgary Scale), catamnestic and clinic-laboratory methods (determination of brain-derived neurotrophic factor BDNF, proinflammatory cytokine interleukin-6, C-reactive protein). Results. At the stabilization stage, depression in patients with paranoid schizophrenia occurred in 19% of cases, more frequently in women. Female patients were more severely depressed, which was associated with an increased concentration of C-reactive protein, while negative symptoms predominated in male patients as compared to females. The presence of depression correlates with a lower severity of psychopathological, primarily positive symptoms and with a greater severity of neurocognitive deficit in schizophrenic patients. BDNF level directly correlates with the severity of positive and negative symptoms, and the level of interleukin 6 at the stage of remission formation does not differ from that in healthy individuals. C-reactive protein levels are associated with the characteristics of the course of schizophrenia.

Validity and utility of Hierarchical Taxonomy of Psychopathology (HiTOP): II. Externalizing superspectrum

The Hierarchical Taxonomy of Psychopathology (HiTOP) is an empirical effort to address limitations of traditional mental disorder diagnoses. These include arbitrary boundaries between disorder and normality, disorder co-occurrence in the modal case, heterogeneity of presentation within dis-orders, and instability of diagnosis within patients. This paper reviews the evidence on the validity and utility of the disinhibited externalizing and antagonistic externalizing spectra of HiTOP, which together constitute a broad externalizing superspectrum. These spectra are composed of elements subsumed within a variety of mental disorders described in recent DSM nosologies, including most notably substance use disorders and "Cluster B" personality disorders. The externalizing superspectrum ranges from normative levels of impulse control and self-assertion, to maladaptive disinhibition and antagonism, to extensive polysubstance involvement and personality psychopathology. A rich literature supports the validity of the externalizing superspectrum, and the disinhibited and antagonistic spectra. This evidence encompasses common genetic influences, environmental risk factors, childhood antecedents, cognitive abnormalities, neural alterations, and treatment response. The structure of these validators mirrors the structure of the phenotypic externalizing superspectrum, with some correlates more specific to disinhibited or antagonistic spectra, and others relevant to the entire externalizing superspectrum, underlining the hierarchical structure of the domain. Compared with traditional diagnostic categories, the externalizing superspectrum conceptualization shows improved utility, reliability, explanatory capacity, and clinical applicability. The externalizing superspectrum is one aspect of the general approach to psychopathology offered by HiTOP and can make diagnostic classification more useful in both research and the clinic.

Exploring the Psychometric Properties and the Factor Structure of the Calgary Depression Scale for Schizophrenia Across the Schizotypy Continuum

This study evaluated the psychometric properties and factor structure of the Calgary Depression Scale for Schizophrenia (CDSS) across different levels of the schizotypy continuum. A combined sample of high-schizotypy, at-risk mental states, and patients with first-episode psychosis was assessed for depression and other clinical and functional outcomes. Additionally, experience sampling methodology was used to assess depressive and psychotic-like experiences in daily life. The CDSS exhibited solid internal consistency, validity, and discrimination between depressed and nondepressed participants. Confirmatory factor analyses and the associations of the resulting factors with clinical and functional measures supported a two-factor structure that included general depression and guilt factors. Furthermore, both factors of the CDSS were differentially related to positive and negative symptoms of psychosis in daily life. The CDSS appears to have two underlying psychopathological dimensions and to be a reliable and valid measure for assessing depression across the schizotypy continuum.

Validity and utility of Hierarchical Taxonomy of Psychopathology (HiTOP): I. Psychosis superspectrum

The Hierarchical Taxonomy of Psychopathology (HiTOP) is a scientific effort to address shortcomings of traditional mental disorder diagnoses, which suffer from arbitrary boundaries between psychopathology and normality, frequent disorder co-occurrence, heterogeneity within disorders, and diagnostic instability. This paper synthesizes evidence on the validity and utility of the thought disorder and detachment spectra of HiTOP. These spectra are composed of symptoms and maladaptive traits currently subsumed within schizophrenia, other psychotic disorders, and schizotypal, paranoid and schizoid personality disorders. Thought disorder ranges from normal reality testing, to maladaptive trait psychoticism, to hallucinations and delusions. Detachment ranges from introversion, to maladaptive detachment, to blunted affect and avolition. Extensive evidence supports the validity of thought disorder and detachment spectra, as each spectrum reflects common genetics, environmental risk factors, childhood antecedents, cognitive abnormalities, neural alterations, biomarkers, and treatment response. Some of these characteristics are specific to one spectrum and others are shared, suggesting the existence of an overarching psychosis superspectrum. Further research is needed to extend this model, such as clarifying whether mania and dissociation belong to thought disorder, and explicating processes that drive development of the spectra and their subdimensions. Compared to traditional diagnoses, the thought disorder and detachment spectra demonstrated substantially improved utility: greater reliability, larger explanatory and predictive power, and higher acceptability to clinicians. Validated measures are available to implement the system in practice. The more informative, reliable and valid characterization of psychosis-related psychopathology offered by HiTOP can make diagnosis more useful for research and clinical care.

Low plasma concentrations of N-methyl-d-aspartate receptor subunits as a possible biomarker for psychosis

BACKGROUND

N-methyl-d-aspartate receptor (NMDAR) has been largely implicated in the neurobiology of schizophrenia and other psychosis. Aiming to evaluate their potential as peripheral biomarkers for psychosis, we quantified the plasma concentrations of NR1 and NR2 NMDAR subunits of first-episode psychosis patients in their first contact with mental health services due to psychotic symptoms, compared with siblings and matched community-based controls.

METHODS

The quantifications of NR1 and NR2 plasma concentrations were performed by ELISA. Data were analysed by nonparametric tests and Receiver Operating Curve (ROC) analysis.

RESULTS

We included 166 first-episode psychosis patients (mean age = 30.3 ± 12.2 years; 64% men), with the diagnosis of schizophrenia spectrum (n = 84), bipolar disorder (n = 51) and psychotic depression (n = 31), 76 siblings (mean age = 31.5 ± 11.0 years; 30.3% men) and 166 healthy community-based controls (mean age = 31.4 ± 12.0 years; 63.9% men). NMDAR subunits were significantly lower in patients compared with siblings and controls (p < 0.001), except by NR1 plasma concentrations of bipolar patients compared with siblings and controls. NR1 plasma concentrations lower than 17.65 pg/ml (AUC = 0.621) showed sensitivity of 42.8%, specificity of 84.3%, positive predictive value (PPV) of 73.2% and negative predictive value (NPV) of 59.6%. Individuals with NR2 plasma concentrations lower than 2.92 ng/ml (AUC = 0.801) presented a 10.61-fold increased risk of psychosis, with a sensibility of 71.9%, specificity of 80.6%, PPV of 79.0% and NPV of 73.9%.

CONCLUSIONS

This is the first study reporting the measurement and the reduction of NR1 and NR2 NMDAR subunits plasma concentrations in psychiatric disorders. In particular, the NR2 subunit may be a possible plasma biomarker for psychosis.

Indication of Disrupted Temporal Structure in the Case of Thought Blocks in Schizophrenia: The Role of the Metastable Balance

This study is aimed at investigating probable disruption of the metastable balance relevant to a disruption of the mental processes observed in the neurophenomenal level. This disruption was found to occur under dense auditory verbal hallucinations (AVHs) which are accompanied by thought blocking (TB) phenomena. The entropy that quantifies the complexity of the spontaneous coupling has been used to describe the observed transitions. According to our findings, the high synchrony-derived entropy (SE) defines a metastable state, where formations of cortical areas are able to coordinate transiently under the demands of stimulus-oriented processes or other internal cognitive associations. It was also found that the disruption of the sensitive balance to the side of oversynergy (overconnectedness) rather than the side of independence (coincidental coupling) is relevant with functional fixations under the specific symptom of schizophrenia. An introduced measure relative to the persistence of coupling indicated that the overcoupled brain areas exhibit a kind of “stiffness” in processing incoherent phasic components. Our consideration enhances the understanding of the role the metastability plays in the interpretation of deeply subjective phenomena, such as AVHs and TBs that affect the normal information routing in the brain.

Top Mysteries of the Mind: Insights From the Default Space Model of Consciousness

Aside from the nature of consciousness itself, there are still many unsolved problems in the neurosciences. Despite the vast and quickly growing body of work in this field, we still find ourselves perplexed at seemingly simple qualities of our mental being such as why we need to sleep. The neurosciences are at least beginning to take a hold on these mysteries and are working toward solving them. We hold a perspective that metastable consciousness models, specifically the Default Space Model (DSM), provide insights into these mysteries. In this perspective article, we explore some of these curious questions in order to elucidate the interesting points they bring up. The DSM is a dynamic, global theory of consciousness that involves the maintenance of an internal, 3D simulation of the external, physical world which is the foundation and structure of consciousness. This space is created and filled by multiple frequencies of membrane potential oscillations throughout the brain and body which are organized, synchronized and harmonized by the thalamus. The veracity of the DSM is highlighted here in its ability to further understanding of some of the most puzzling problems in neuroscience.

Psychotic-spectrum symptoms, cumulative adversity exposure and substance use among high-risk girls

AIM

Psychotic-spectrum symptoms are linked to trauma, substance/alcohol use (SAU), criminality/violence and poor functional outcomes, supporting the need for early detection in vulnerable populations. To better understand high-risk girls' mental health, we assessed: (1) psychotic-spectrum symptoms; (2) cumulative trauma, adversity and loss exposures (C-TALE) and adversity-indicators (symptoms, maladaptive coping, stressor-reactivity); and SAU risk-factors; and (3) relationships among psychotic-spectrum symptoms, adversity-indicators and SAU risk-factors.

METHODS

We administered the Structured Clinical Interviews for Psychotic Spectrum, and Trauma and Loss Spectrum to 158 adolescent delinquent girls.

RESULTS

Girls' psychotic-spectrum profiles were similar to previously reported adult psychotic patients and characterized by typical symptoms (hallucinations/delusions, reported largely SAU-independent), interpersonal sensitivity, schizoid traits and paranoia (over-interpretation, anger over-reactivity, hypervigilance). Auditory/visual hallucinations (55.7%), delusions (92.4%), ideas of reference (96.8%) and adversity (90.0% ≥10/24 C-TALE-types) were common. Mean loss (4) and trauma (8) onset-age occurred before SAU-onset (12). Significant positive correlations were found among psychotic-spectrum symptoms, stressor-reactivity, C-TALE, adversity-indicators; and number of SAU-types; and a negative correlation occurred between psychotic-spectrum symptoms and earlier alcohol use onset. After controlling for number of SAU-types, stressor-reactivity and adversity-related numbing individually had the largest associations with total psychotic-spectrum symptoms (b = 2.6-4.3). Girls averaged more than 4 maladaptive coping strategies (e.g., 24.8% attempted suicide) in response to adversity, amplifying potential health-disparities. No racial/ethnic differences emerged on psychotic-spectrum symptoms.

CONCLUSIONS

This symptom constellation during adolescence likely interferes with social and academic functioning. Whether representing a prodromal phase, trauma-response or cross-diagnostic psychopathology, accurate early detection and appropriate treatment of psychotic-spectrum symptoms are warranted to improve functional outcomes in vulnerable populations.

Declining Clinical Course of Psychotic Disorders Over the Two Decades Following First Hospitalization: Evidence From the Suffolk County Mental Health Project

OBJECTIVE

Kraepelin considered declining course a hallmark of schizophrenia, but others have suggested that outcomes usually stabilize or improve after treatment initiation. The authors investigated this question in an epidemiologically defined cohort with psychotic disorders followed for 20 years after first hospitalization.

METHOD

The Suffolk County Mental Health Project recruited first-admission patients with psychosis from all inpatient units of Suffolk County, New York (response rate, 72%). Participants were assessed in person six times over two decades; 373 completed the 20-year follow-up (68% of survivors); 175 had schizophrenia/schizoaffective disorder. Global Assessment of Functioning (GAF), psychotic symptoms, and mood symptoms were rated at each assessment. Month 6, when nearly all participants were discharged from the index hospitalization, was used as a reference.

RESULTS

In the schizophrenia group, mean GAF scores declined from 49 at month 6 to 36 at year 20. Negative and positive symptoms also worsened (Cohen's d values, 0.45-0.73). Among participants without schizophrenia, GAF scores were higher initially (a mean of approximately 64) but declined by 9 points over the follow-up period. Worsening began between years 5 and 8. Neither aging nor changes in antipsychotic treatment accounted for the declines. In all disorders, depression improved and manic symptoms remained low across the 20 years.

CONCLUSIONS

The authors found substantial symptom burden across disorders that increased with time and ultimately may undo initial treatment gains. Previous studies have suggested that better health care delivery models may preempt this decline. In the United States, these care needs are often not met, and addressing them is an urgent priority.

Comprehensive Psychopathological Assessment Based on the Association for Methodology and Documentation in Psychiatry (AMDP) System: Development, Methodological Foundation, Application in Clinical Routine, and Research

The documentation of psychopathology is core to the clinical practice of the psychiatrist and clinical psychologist. However, both in initial as well as further training and specialization in their fields, this particular aspect of their work receives scanty attention only. Yet, for the past 50 years, the Association for Methodology and Documentation in Psychiatry (AMDP) System has been in existence and available as a tool to serve precisely the purpose of offering a systematic introduction to the terminology and documentation of psychopathology. The motivation for its development was based on the need for an assessment procedure for the reliable documentation of the effectiveness of newly developed psychopharmacological substances. Subsequently, the AMDP-System began to be applied in the context of investigations into a number of methodological issues in psychiatry (e.g., the frequency and specificity of particular symptoms, the comparison of rating scales). The System then became increasingly important also in clinical practice and, today, represents the most used instrument for the documentation of psychopathology in the German-speaking countries of Europe. This paper intends to offer an overview of the AMDP-System, its origins, design, and functionality. After an initial account of the history and development of the AMDP-System, the discussion will in turn focus on the System's underlying methodological principles, the transfer of clinical skills and competencies in its practical application, and its use in research and clinical practice. Finally, potential future areas of development in relation to the AMDP-System are explored.

Natural language processing to extract symptoms of severe mental illness from clinical text: the Clinical Record Interactive Search Comprehensive Data Extraction (CRIS-CODE) project

OBJECTIVES

We sought to use natural language processing to develop a suite of language models to capture key symptoms of severe mental illness (SMI) from clinical text, to facilitate the secondary use of mental healthcare data in research.

DESIGN

Development and validation of information extraction applications for ascertaining symptoms of SMI in routine mental health records using the Clinical Record Interactive Search (CRIS) data resource; description of their distribution in a corpus of discharge summaries.

SETTING

Electronic records from a large mental healthcare provider serving a geographic catchment of 1.2 million residents in four boroughs of south London, UK.

PARTICIPANTS

The distribution of derived symptoms was described in 23 128 discharge summaries from 7962 patients who had received an SMI diagnosis, and 13 496 discharge summaries from 7575 patients who had received a non-SMI diagnosis.

OUTCOME MEASURES

Fifty SMI symptoms were identified by a team of psychiatrists for extraction based on salience and linguistic consistency in records, broadly categorised under positive, negative, disorganisation, manic and catatonic subgroups. Text models for each symptom were generated using the TextHunter tool and the CRIS database.

RESULTS

We extracted data for 46 symptoms with a median F1 score of 0.88. Four symptom models performed poorly and were excluded. From the corpus of discharge summaries, it was possible to extract symptomatology in 87% of patients with SMI and 60% of patients with non-SMI diagnosis.

CONCLUSIONS

This work demonstrates the possibility of automatically extracting a broad range of SMI symptoms from English text discharge summaries for patients with an SMI diagnosis. Descriptive data also indicated that most symptoms cut across diagnoses, rather than being restricted to particular groups.

Cortisol and BDNF levels in depression within schizophrenia structure: approach to treating

To evaluate the effect of depression on the level of cortisol and BDNF in patients with schizophrenia 25 inpatients, who met the diagnostic criteria for ICD-10 schizophrenia (F20), were examined. The examination included clinical, psychopathological, laboratory and psychometric methods. Patients were examined twice: at admission and after 6 weeks of treatment. It was found that the level of BDNF in schizophrenic patients with depressive symptoms was significantly lower than that of non-depressed patients, and the level of cortisol in patients with depression was significantly higher.

Platelet serotonin concentration and depressive symptoms in patients with schizophrenia

Depressive symptoms seem to be frequent in schizophrenia, but so far they have received less attention than other symptom domains. Impaired serotonergic neurotransmission has been implicated in the pathogenesis of depression and schizophrenia. The objectives of this study were to investigate platelet serotonin concentrations in schizophrenic patients with and without depressive symptoms, and to investigate the association between platelet serotonin concentrations and symptoms of schizophrenia, mostly depressive symptoms. A total of 364 patients were included in the study, 237 of which had significant depressive symptoms. Significant depressive symptoms were defined by the cut-off score of 7 or more on Calgary Depression Rating Scale (CDSS). Platelet serotonin concentrations were assessed by the enzyme-linked immunosorbent assay (ELISA). Prevalence of depression in patients with schizophrenia was 65.1%. Schizophrenic patients with depressive symptoms showed lower platelet serotonin concentrations (mean±SD; 490.6±401.2) compared to schizophrenic patients without depressive symptoms (mean±SD; 660.9±471.5). An inverse correlation was established between platelet serotonin concentration and depressive symptoms, with more severe symptoms being associated with lower platelet serotonin concentrations. Depressive symptoms in schizophrenic patients may be associated with reduced concentrations of platelet serotonin.

A dimensional comparison between delusional disorder, schizophrenia and schizoaffective disorder

INTRODUCTION

Since the early description of paranoia, the nosology of delusional disorder has always been controversial. The old idea of unitary psychosis has now gained some renewed value from the dimensional continuum model of psychotic symptoms.

AIMS

1. To study the psychopathological dimensions of the psychosis spectrum; 2. to explore the association between psychotic dimensions and categorical diagnoses; 3. to compare the different psychotic disorders from a psychopathological and functional point of view.

MATERIAL AND METHODS

This is an observational study utilizing a sample of some 550 patients with a psychotic disorder. 373 participants had a diagnosis of schizophrenia, 137 had delusional disorder and 40 with a diagnosis of schizoaffective disorder. The PANSS was used to elicit psychopathology and global functioning was ascertained using the GAF measure. Both exploratory and confirmatory factor analyses of the PANSS items were performed to extract psychopathological dimensions. Associations between diagnostic categories and dimensions were subsequently studied using ANOVA tests.

RESULTS

5 dimensions - manic, negative symptoms, depression, positive symptoms and cognitive - emerged. The model explained 57.27% of the total variance. The dimensional model was useful to explained differences and similarities between all three psychosis spectrum categories. The potential clinical usefulness of this dimensional model within and between clinical psychosis spectrum categories is discussed.

Clinical & diagnostic issues in catatonia

The concept of catatonia was formulated in the 1860s by Karl Ludwig Kahlbaum. He coined and gave the name catatonia to the syndromic entity in which the mood symptoms (depression and mania) were primary, and motor symptoms (mutism, negativism, stereotypies, catalepsy and verbigeration) the most characteristic. Although the name has remained stable, this concept has changed in the last century concerning the details of its definition until the current integrative approach in DSM 5. Catatonic phenomena are main components of the ‘motor abnormalities’ domain in psychiatric, neurologic and general medical disorders and they have to be evaluated in the context of a full psychopatological and neurological examination. In this article, we make a review about clinical and diagnostic issues in catatonia. Catatonic phenomena comprise both state and trait characteristics and have prognostic validity in psychosis. Moreover, providing that motor abnormalities are closer to neurobiological underpinnings than other psychotic symptoms (e.g., positive symptoms of schizophrenia), catatonic phenomena should be studied specifically as targets for neurobiological research.

Understanding psychopathology in migrants: a mixed categorical-dimensional approach

BACKGROUND

Literature on mental disorders in migrants is constantly increasing. Only a few studies describe psychopathological dimensions in migrants over their nosographic diagnoses; however, there is a growing literature about the greater utility of a categorical-dimensional approach, rather than a solely categorical approach, in the understanding of mental disorders. The aim of this paper is to describe the phenomenology of mental disorders in migrants referred to the Transcultural Psychiatric Team of Bologna (BoTPT), by analysing the psychopathological dimensions that underlie their clinical diagnoses.

METHODS

We recruited all migrants who attended the BoTPT between May 1999 and July 2009. The psychopathological assessment was conducted with the Association for Methodology and Documentation in Psychiatry (AMDP) and clinical diagnoses were formulated according to ICD-10. We proceeded through a two-step analysis: (1) comparing the prevalence rates of psychopathological symptoms across diagnoses; then (2) conducting a factor analysis to assess how those symptoms configure psychopathological dimensions and how these dimensions underlie clinical diagnoses.

RESULTS

As expected, we found significant associations between diagnoses and the prevalence of their core psychopathological symptoms. Factor analysis revealed a strong polymorphism of the psychopathological presentation of mental disorders and unexpectedly showed that in each diagnostic cluster, the first extracted factor was not composed of core symptoms.

CONCLUSIONS

A mixed categorical-dimensional approach seems to improve the description of the psychopathology among migrants, as it adds relevant information regarding psychopathological dimensions useful to the understanding of the peculiar clinical expressivity of our patients.

Association between symptom dimensions and categorical diagnoses of psychosis: a cross-sectional and longitudinal investigation

CONTEXT

Cross-sectional studies of the signs and symptoms of psychosis yield dimensional phenotypes. However, the validity and clinical utility of such dimensions remain debated. This study investigated the structure of psychotic symptomatology, the stability of the structure over time, and the concordance between symptom dimensions and categorical diagnoses.

METHODS

Sample consisted of 500 first-episode psychotic patients. A cross-sectional study (N = 500) investigated the organizational structure of symptom dimensions at the onset of psychosis and its concordance with categorical diagnoses; next, a nested longitudinal study (N = 100) examined the stability of the symptom dimensions structure after 5-10 years of follow-up.

RESULTS

Factor analyses identified 6 first-order factors (mania, negative, disorganization, depression, hallucinations, and delusions) and 2 high-order factors (affective and nonaffective psychoses). Cumulative variance accounted for by the first and high-order factors was 63%: 31% by the first-order factors and 32% by the high-order factors. The factorial structure of psychotic symptoms during first episode remained stable after 5-10 years of follow-up. The overall concordance between 4 categorical diagnostic groups (schizophrenia, mania with psychosis, psychotic depression and schizoaffective disorder) and dimensional symptom ranged from 62.2% to 73.1% (when the schizoaffective group was excluded).

CONCLUSIONS

Symptoms of psychosis assume a multidimensional hierarchical structure. This hierarchical model was stable over time and showed good concordance with categorical diagnoses. The combined use of dimensional and categorical approach to psychotic disorders would be of clinical and research utility.

The low- and higher-order factor structure of symptoms in patients with a first episode of psychosis

BACKGROUND

The phenotype of psychotic disorders is presumed to be heterogeneous, but the best way to describe this heterogeneity remains unclear.

OBJECTIVE

To examine the lower-order and higher-order symptomatic architecture of psychotic disorders by means of factor analysis and the Schmid-Leiman transformation.

METHODS

Patients experiencing their first episode of psychosis (n=486) were comprehensively examined for 70 symptomatic variables, which were subjected to principal components analysis followed by a Promax rotation. First-order factors were subjected to second-order factor analysis, and influence of second-order factors on primary factors was removed using the Schmid-Leiman transformation.

RESULTS

First-order factor analysis revealed 13 primary factors that were substantially intercorrelated. Second-order factor analysis showed 5 higher-order factors with no substantial intercorrelations. The Schmid-Leiman transformation revealed that whereas the second-order factors accounted for most of the symptom covariance (63.5%), the first-order factors still accounted for an additional 36.5%. According to this transformation, five second-order factors (bipolar negative-mania, disorganization, psychomotor retardation, hallucinations and grandiosity) plus four first-order factors (depression, catatonia, bizarre delusions and paranoid delusions) best explained the factor structure of the symptoms.

CONCLUSIONS

The phenotype of psychosis is more complex than previously acknowledged as it embraces a multidimensional hierarchical structure organized into nonredundant first- and second-order factors.

Categorical vs dimensional classifications of psychotic disorders

OBJECTIVE

Both categorical and dimensional methods appear relevant to classifying psychotic disorders; however, there is no clear consensus on the most appropriate categories and dimensions or on the best approach for constructing nosologic criteria that integrate these 2 methods. This review examines the evidence on specific dimensions and categories that would best characterize psychoses.

METHOD

Entries in the MEDLINE database between 1980 and 2011 were searched for studies of the dimensional and/or categorical structure of psychosis. Studies were included if samples represented a spectrum of psychotic disorders and dimensions/categories were empirically derived using principal components analysis, factor analysis, or latent class analysis.

RESULTS

Most dimensional studies observed 4 or 5 dimensions within psychosis, with positive, negative, disorganization, and affective symptom domains most frequently reported. Substance abuse, anxiety, early onset/developmental, insight, cognition, hostility, and behavioral/social disturbance dimensions appeared in some studies. Categorical studies suggested 3 to 7 major classes within psychosis, including a class similar to Kraepelin's dementia praecox and one or more classes with significant mood components. Only 2 studies compared the relative fit of empirically derived dimensions and categories within the same data set, and each had significant limitations.

CONCLUSION

There is relatively consistent evidence on appropriate categories and dimensions for characterizing psychoses. However, the lack of studies directly comparing or combining these approaches provides insufficient evidence for definitive conclusions about their relative merits and integration. The authors provide specific recommendations for designing future studies to identify valid dimensions and/or categories of the psychoses and investigate hybrid approaches to model the structure of the underlying illnesses.

Analysis of OPCRIT results indicate the presence of a novel 'social functioning' domain and complex structure of other dimensions in the Wielkopolska (Poland) population

OBJECTIVE

The main goal of our study was to examine factor structure of schizophrenia and bipolar affective disorder in the Wielkopolska population, using dimension reduction techniques.

METHODS

Schizophrenia (n=443) and bipolar affective disorder (n=499) patients were assessed using Operational Criteria Checklist (OPCRIT). Principal component analysis and Maximum Likelihood Factor analysis were carried out to obtain factor structure with significance level for the factor loadings exceeding 0.4. Varimax and promax rotations were used to identify the meaningful factors.

RESULTS

Rotated solution indicated multidimensional structure for depression and excitement as well as positive domains in the schizophrenia sample. Negative and disorganized dimensions existed as single factors, with item composition similar to that already described. Additionally, a new "social functioning" dimension was identified. In bipolar affective disorder sample, the interpretable dimensions included: depression, psychotic, atypical depression, negative, substance use, excitement and "social functioning". Factor structure of the combined sample consisted of depression, excitement, disorganization, delusions, substance use, negative and social functioning factors.

CONCLUSIONS

Our results indicated multidimensional and hierarchical structures for some of the previously described dimensions. Additional use of items not exactly related to disease symptoms lead to discovery of "substance use" and "social functioning" dimensions.

Exploring the structure of psychopathological symptoms: a re-analysis of AMDP data by robust nonmetric multidimensional scaling

This paper investigates the structure of psychopathological symptoms. Based on AMDP symptom profiles, a symptom space was calculated by robust nonmetric multidimensional scaling (NMDS) and the symptom structures of a sample dating from 1980 and a sample from 2002/2003 were compared. The method of NMDS presented in this study allows results from other studies to be confirmed and complemented. The symptom factors identified in the past by factor-analytic studies were replicated as clusters in two-dimensional symptom maps. Additionally, some theoretically assumed clusters of symptoms were detected that were not found in previous factor analysis approaches. From the results, which are depicted in a continuous space, new insights can be gained, especially with regard to questions of categorical and dimensional classifications. The comparison of the structural aspects of the symptomatology across more than two decades resulted in only small divergences and allows conclusions to be drawn about the stability of these structures and consequently of the symptom clusters and dimensions.

Copy number variants in a sample of patients with psychotic disorders: is standard screening relevant for actual clinical practice?

With the introduction of new genetic techniques such as genome-wide array comparative genomic hybridization, studies on the putative genetic etiology of schizophrenia have focused on the detection of copy number variants (CNVs), ie, microdeletions and/or microduplications, that are estimated to be present in up to 3% of patients with schizophrenia. In this study, out of a sample of 100 patients with psychotic disorders, 80 were investigated by array for the presence of CNVs. The assessment of the severity of psychiatric symptoms was performed using standardized instruments and ICD-10 was applied for diagnostic classification. In three patients, a submicroscopic CNV was demonstrated, one with a loss in 1q21.1 and two with a gain in 1p13.3 and 7q11.2, respectively. The association between these or other CNVs and schizophrenia or schizophrenia-like psychoses and their clinical implications still remain equivocal. While the CNV affected genes may enhance the vulnerability for psychiatric disorders via effects on neuronal architecture, these insights have not resulted in major changes in clinical practice as yet. Therefore, genome-wide array analysis should presently be restricted to those patients in whom psychotic symptoms are paired with other signs, particularly dysmorphisms and intellectual impairment.

Depressive symptoms evaluated by the Calgary Depression Scale for Schizophrenia (CDSS): genetic vulnerability and sex effects

The present study compares the occurrence of depressive symptoms evaluated by the Calgary Depression Scale for Schizophrenia (CDSS) in patients of Multiplex (MS) and Simplex Schizophrenia families (SS). The Positive and Negative Syndrome Scale (PANSS) was used to evaluate psychopathology. A total of 206 paranoid schizophrenia patients were studied according DSM-IV criteria. The Family Interview for Genetic Studies (FIGS) was used to study the families. A result in the FIGS for a positive family history of schizophrenia was referred as MS (patients); its lack as SS (patients). CDSS scores were compared among MS and SS patients and possible sex differences intra- and inter-groups were explored. In the analysis of our sample (30) 19% of the total persons with schizophrenia group was depressed. The depressive symptoms measured by the CDSS were higher in females and the MS males group. Males from MS group showed more depressive symptoms than males from SS group. No differences with females from both groups were found. Findings in this study underscore the importance of gender and family history in understanding the heterogeneity of schizophrenia. This study suggests that sex and familiar history are important to consider in studying depressive symptoms.

Combining the categorical and the dimensional perspective in a diagnostic map of psychotic disorders

We introduce a diagnostic map that was calculated by robust non-metric multidimensional scaling based on AMDP symptom profiles of patients with schizophrenic and affective disorders to demonstrate a possibility to combine the categorical and the dimensional perspective at the same time. In the diagnostic map, a manic, a depressive, and a non-affective cluster clearly emerged. At the same time, the mania dimension (r = 0.82), the depression dimension (r = 0.68), and the apathy dimension (r = 0.74) showed high multiple regression values in the map. We found substantial overlaps of the diagnostic groups with regard to the affective spectrum but irrespective of the ICD-10 classification. Within this sample, we found the association and quality of mood symptoms to be a structuring principle in a diagnostic map. We demonstrate that this approach represents a promising way of combining the categorical and the dimensional perspective. As a practical implementation of these findings, a multidimensional diagnostic map could serve as an automated diagnostic tool based on psychopathological symptom profiles.

The negative symptoms of schizophrenia: category or continuum?

Negative symptoms have been considered to be specific to schizophrenia or a subtype of schizophrenia: the deficit syndrome. In other words, these symptoms have been considered to be categorically different from other forms of human behavior and experience, whether they occur in healthy persons or patients with other psychiatric disorders. In this paper, we advocate a dimensional approach to negative symptoms, which is supported by two main arguments. First, enduring negative symptoms can even be observed in a variety of psychiatric disorders and they are not specific to schizophrenia. Second, we review evidence that negative symptoms show a continuous distribution from apparently healthy subjects to those with a fully developed clinical syndrome. Although the evidence does not allow for a definite decision concerning the dimensional distribution of negative symptoms, it certainly justifies exploring a dimensional approach with respect to its clinical and scientific utility. Understanding negative symptoms as a variation of normal mental processes will strengthen the development of neurocognitive models and treatment approaches.

The diagnostic concept of schizophrenia: its history, evolution, and future prospects

More than a century since the delineation of dementia praecox by Kraepelin, the etiology, neuropathology and pathophysiology of schizophrenia remain elusive. Despite the availability of criteria allowing reliable diagnostic identification, schizophrenia essentially remains a broad clinical syndrome defined by reported subjective experiences (symptoms), loss of function (behavioral impairments), and variable patterns of course. Research has identified a number of putative biological markers associated with the disorder, including neurocognitive dysfunction, brain dysmorphology, and neurochemical abnormalities. Yet none of these variables has to date been definitively proven to possess the sensitivity and specificity expected of a diagnostic test. Genetic linkage and association studies have targeted multiple candidate loci and genes, but failed to demonstrate that any specif ic gene variant, or a combination of genes, is either necessary or sufficient to cause schizophrenia. Thus, the existence of a specific brain disease underlying schizophrenia remains a hypothesis. Against a background of an ever-increasing volume of research data, the inconclusiveness of the search for causes of the disorder fuels doubts about the validity of the schizophrenia construct as presently defined. Given the protean nature of the symptoms of schizophrenia and the poor coherence of the clinical and biological findings, such doubts are not without reason. However, simply dismantling the concept is unlikely to result in an alternative model that would account for the host of clinical phenomena and research data consistent with a disease hypothesis of schizophrenia. For the time being, the clinical concept of schizophrenia is supported by empirical evidence that its multiple facets form a broad syndrome with non-negligible internal cohesion and a characteristic evolution over time. The dissection of the syndrome with the aid of endophenotypes is beginning to be perceived as a promising approach in schizophrenia genetics.

Association of adolescent catatonia with increased mortality and morbidity: evidence from a prospective follow-up study

This paper examined outcomes among youth with catatonic syndrome and determined whether the characteristics suggesting the relevance of chronic catatonic schizophrenia (CCS) at index episode remained stable at follow-up. From 1993 to 2004, 35 individuals aged 12 to 18 years were prospectively admitted for management of catatonic syndrome and followed up after discharge. Mean duration from discharge to follow-up was 3.9 years (range 1-10). Four patients were lost to follow-up. Among the remaining 31 subjects (mean age=19.5 years, range 15-26), life-time diagnosis using the Diagnostic Interview for Genetic Studies was unchanged in 28 patients, and included schizophrenia (all subtypes; N=20), major depressive episode (N=5), bipolar disorder type I (N=4) and brief psychotic episode (N=2). Mortality (all-cause Standardized Mortality Ratio=6266; 95% CI=1181-18,547) and morbidity were severe, with 3 deaths (including 2 suicides), 6 patients presenting with a causal organic condition and 14 subjects needing continuous psychiatric care. All males in the study (N=8) who had chronic catatonic schizophrenia at the index episode still had chronic catatonic signs at follow-up. Catatonia is one of the most severe psychiatric syndromes in adolescents. It is associated with a 60-fold increased risk of premature death, including suicide, when compared to the general population of same sex and age. This increased risk of premature death remains higher than the one measured in former adolescent psychiatric patients (all-cause SMR=221; 95% CI=156-303; Engqvist and Rydelius, 2006), or in schizophrenia irrespective to age and subtype (all-cause SMR=157; 95% CI=153-160; Harris and Barraclough, 1998).

Standardised rating scales in psychiatry: methodological basis, their possibilities and limitations and descriptions of important rating scales

Standardized rating scales are an important tool to improve the assessment of psychopathological symptoms in terms of validity and reliability. Especially observer-rated scales are of primary importance in this respect. Self-rating scales can give a meaningful complementary view to the findings of observer-rated scales. Besides scales covering more or less the whole spectrum of psychopathological symptoms, specialised scales focussing only on symptoms of disorders like schizophrenia or depression were developed. They are widely used, specifically for pragmatic reasons.

Psychopathological assessment of schizophrenia: relevance for classification

Considerable effort has been focused on updating the clinical aspects of psychiatric classifications based on recent progress in the field of neurobiology. In this article, recent developments in the primary assessment methods within clinical psychiatry, which are based in phenomenological psychopathology, are reviewed as nosotaxies that are still embedded in clinical description. New directions for research on psychopathology are outlined to elicit better descriptions of subjective experience from patients. Finally, the known limitations of the Kraepelinian dichotomy are summarized, and future problems related to the inclusion of the new dimensional assessment methods in the next psychiatric classifications are described.

Creating a map of psychiatric patients based on psychopathological symptom profiles

BACKGROUND

In the current debate about the categorical or dimensional classification of mental disorders many fruitful methods to illustrate one or the other aspect are employed, and suggestions are made to combine the two perspectives.

METHODS

We present such an approach to combine both perspectives at the same time. Based on psychopathological AMDP-symptom profiles, a map of psychiatric patients was calculated by robust nonmetric multidimensional scaling (NMDS).

RESULTS

The sample from the Ludwig-Maximilians University in Munich included the records of patients, who were admitted and discharged in 2002 and 2003 with a diagnosis of either paranoid schizophrenia, (F20.00, N = 24), bipolar affective disorder, current episode manic without psychotic symptoms (F31.1, N = 32) or severe depressive episode without psychotic symptoms (F32.2, N = 78). In the resulting map of patients we found a clear categorical distinction according to the diagnostic groups, but also high regression values of AMDP-syndromes (manic syndrome: r = 0.83, depressive syndrome: r = 0.68, and paranoid-hallucinatory syndrome, r = 0.62).

DISCUSSION

The map of psychiatric patients presents an approach to consider the categorical and dimensional aspects at the same time. We were able to identify meaningful delineations between diagnostic clusters as well as continuous transitions. This method allows the whole psychopathological profile of each individual patient to be considered and also to identify misdiagnosed cases at a glance.

Multidisciplinary approach of organic catatonia in children and adolescents may improve treatment decision making

Catatonia is an infrequent but severe condition in young people. Organic diseases may be associated and need to be investigated though no specific recommendations and guidelines are available. We extensively reviewed the literature of all the cases of organic catatonia in children and adolescents from January 1969 to June 2007. We screened socio-demographic characteristics, organic diagnosis, clinical characteristics and treatment. We found 38 cases of children and adolescents with catatonia due to an organic condition. The catatonic syndrome occurred in 21 (57%) females and 16 (43%) males. The mean age of patients was 14.5 years (+/-3.39) [range=7-18 years], and three died from their condition. The organic conditions included infectious diseases (N=10), neurological conditions (N=10), toxic induced states (N=12) and genetic conditions including inborn errors of metabolism (N=6). The onset was dominantly acute, and the clinical presentation most frequently stuporous. Although benzodiazepines were recommended as primary symptomatic treatment, they were rarely prescribed. In several cases, therapeutic approach was related to organic cause (e.g., plasma exchange in lupus erythematosus; copper chelators in Wilson's disease). Based on this review and on our own experience of catatonia in youth, we proposed a consensual and multidisciplinary diagnostic strategy to help practitioners to identify underlying organic diseases.

Psychopathology factors in first-episode affective and non-affective psychotic disorders

BACKGROUND

Since the onset, prevalence, and course of specific psychopathological features rarely have been analyzed simultaneously from the start of dissimilar psychotic illnesses, we compared symptom-clusters in first-episode DSM-IV affective and non-affective psychotic disorders.

METHODS

Subjects (N=377) from the McLean-Harvard First Episode Project hospitalized for first-lifetime primary psychotic illnesses were followed prospectively for 2 years to verify stable DSM-IV diagnoses. We ascertained initial symptoms from baseline SCID and clinical assessments, applying AMDP and Bonn psychopathology schemes systematically to describe a broad range of features. Final consensus diagnoses were based on intake and follow-up SCID assessments, family interviews, and medical records. Factor-analytic methods defined first-episode symptom-clusters (Factors), and multiple-regression modeling related identified factors to initial DSM-IV diagnoses and to later categories (affective, non-affective, or schizoaffective disorders).

RESULTS

Psychopathological features were accommodated by four factors: I represented mania with psychosis; II a mixed depressive-agitated state; III an excited-hallucinatory-delusional state; IV a disorganized-catatonic-autistic state. Each factor was associated with characteristic prodromal symptoms. Factors I and III associated with DSM-IV mania, II with major depression or bipolar mixed-state, III negatively with delusional disorder, IV with major depression and negatively with mania. Factors I and II predicted later affective diagnoses; absence of Factor I features predicted non-affective diagnoses, and no Factor predicted later schizoaffective diagnoses.

CONCLUSION

The findings contribute to descriptive categorizations of psychopathology from onset of dissimilar psychotic illnesses. This approach was effective in identifying and subtyping affective psychotic disorders early in their clinical evolution, but non-affective and schizoaffective conditions appear to be more complex and unstable.

Empirical validation of competing definitions of schizophrenia: a poly-diagnostic study of cognitive impairment in non-affective psychosis

BACKGROUND

The empirical validation of diagnostic criteria for schizophrenia remains a controversial issue within psychiatry and allied sciences. Most diagnostic criteria are still influenced to a large extent by historical and consensus-based perspectives.

METHODS

A poly-diagnostic approach including a set of 23 operationalized diagnostic criteria were administered to probands with non-affective psychosis (n=169). In addition, participants completed a neuropsychological battery during a stable phase of the illness. Attentional, verbal and visual memory and executive functions were assessed. The control group was composed of 26 demographically matched healthy subjects. Analysis of variance was conducted taking neuropsychological performance as response variables and the 23 binary diagnostic systems as explanatory variables.

RESULTS

Four out of the 23 operationalized diagnostic systems for schizophrenia (Feighner, French, Kraepelin and Langfeldt criteria) demonstrated high empirical validity for memory and executive functions scores (medium to moderate effect sizes). These 4 systems resemble classic nosological approaches based upon the 'outcome principle' concept, which suggests that schizophrenia leads to deterioration. However, diagnostic effectiveness of neuropsychological tests for the 23 operationalized diagnostic systems of schizophrenia was low (likelihood ratio <2).

CONCLUSIONS

Neuropsychological functioning provides empirical validation to operationalized definitions of schizophrenia which are mainly based upon deterioration. It is suggested that some inconsistency of neurobiological studies in schizophrenia might result for using solely current consensus-based diagnostic systems. The implementation of poly-diagnostic strategies could contribute to improve the validity of the schizophrenia construct.

A taxometric analysis of schizophrenia symptoms

Specific disorders within the psychosis syndrome have been proposed although no definitive validation of subtypes has been achieved. If there are subtypes of psychosis, latent discontinuity between clinical descriptors should be found. We applied for the first time taxometric analysis on characteristic schizophrenia symptoms. The sample consisted of 660 inpatients with an acute psychotic episode. Computed scores of the clinical dimensions included in the three-syndrome model of schizophrenia symptomatology were used as clinical descriptors or latent variables to be analyzed. Two taxometric analyses were used (MAXCOV and MAMBAC). Discrepancies between observed covariance curves and between the estimated base rates of indicators did not support a taxonic conjecture within psychosis based on the severity of 'Psychosis', 'Negative' and 'Disorganization' dimensions scores, which were used as indicators. However, no appropriate solution could be reached because the three clinical indicators of schizophrenia symptomatology used in this study showed a lack of consistency. The lack of a taxonic structure with symptomatological domains of psychosis suggested the existence of a dimensional solution for schizophrenia symptomatology within psychoses.

The relationship between syndromes of the psychotic illness and familial liability to schizophrenia and major mood disorders

BACKGROUND

Previous studies examining the relationship between psychopathological syndromes of the psychotic illness and familial liability to schizophrenia and mood disorders have obtained inconclusive results. The aim of this study is to further examine this issue by analyzing a large sample of psychotic probands and their first-degree relatives.

METHODS

The sample was composed of 660 psychotic inpatients and their 2987 first-degree relatives. Probands were assessed for index episode and lifetime symptoms, while relatives were assessed for lifetime diagnosis of schizophrenia and major mood disorders. Associations between factor-analysis derived syndromes in probands and familial loading for schizophrenia and major mood disorders were tested.

RESULTS

Familial morbid risk of schizophrenia was predicted by the negative syndrome in probands and familial morbid risk of mood disorders was predicted by mania, depression and catatonia syndromes in probands. This association pattern was relatively independent of type of symptom rating (index episode or lifetime) and probands' diagnosis of schizophrenia or major mood disorder. Familial loading for schizophrenia and mood disorders cut-across the DSM-IV categories of psychotic disorders in probands.

CONCLUSION

From a dimensional perspective, the negative syndrome is related to familial liability to develop schizophrenia. Mania, depression and catatonia syndromes are related to the familial liability to develop major mood disorders. Categories of psychotic disorders are on a continuum of familial liability to schizophrenia and major mood disorders.

Subtyping schizophrenia: implications for genetic research

Phenotypic variability and likely extensive genetic heterogeneity have been confounding the search for the causes of schizophrenia since the inception of the diagnostic category. The inconsistent results of genetic linkage and association studies using the diagnostic category as the sole schizophrenia phenotype suggest that the current broad concept of schizophrenia does not demarcate a homogeneous disease entity. Approaches involving subtyping and stratification by covariates to reduce heterogeneity have been successful in the genetic study of other complex disorders, but rarely applied in schizophrenia research. This article reviews past and present attempts at delineating schizophrenia subtypes based on clinical features, statistically derived measures, putative genetic indicators, and intermediate phenotypes, highlighting the potential utility of multidomain neurocognitive endophenotypes.

Timing in cognition and EEG brain dynamics: discreteness versus continuity

This article provides an overview of recent developments in solving the timing problem (discreteness vs. continuity) in cognitive neuroscience. Both theoretical and empirical studies have been considered, with an emphasis on the framework of operational architectonics (OA) of brain functioning (Fingelkurts and Fingelkurts in Brain Mind 2:291-29, 2001; Neurosci Biobehav Rev 28:827-836, 2005). This framework explores the temporal structure of information flow and interarea interactions within the network of functional neuronal populations by examining topographic sharp transition processes in the scalp EEG, on the millisecond scale. We conclude, based on the OA framework, that brain functioning is best conceptualized in terms of continuity-discreteness unity which is also the characteristic property of cognition. At the end we emphasize where one might productively proceed for the future research.