Meta-analysis of symptom factors in schizophrenia

Subjective quality of life and schizophrenia: results from a large cohort study based in Chinese primary care

INTRODUCTION

Much confusion exists between health-related QoL (HRQoL) scales and subjective QoL (SQoL) scales. One method to avoid confusion is use of a single question that asks What is your quality of life? or similar. This study explored the relationship between biopsychosocial factors and high SQoL, SQoL stability, and factors associated with improving SQoL.

METHOD

We conducted a large cohort study of community-dwelling Chinese adults with schizophrenia, with two data points (2015-2016 (N = 742), 2017-2018 (N = 491)). Demographic and clinically related items and a comprehensive suite of published measures were collected. Direct logistic regressions were used to explore links between biopsychosocial factors and high SQoL and Improvement in SQoL across time.

RESULTS

Sample at Baseline: Male = 62.3%; Med age = 38.5 years; Med Age at illness onset = 24 years; SQoL Mode = neither poor nor good. Three independent variables predicted high SQoL at T1. Contemporary age and the presence of clinically relevant symptoms had a negative relationship with high SQoL; insight had a positive relationship with high SQoL. SQoL changed significantly across time with a modest effect size. Age at illness onset was the single independent variable linked to improving SQoL favoring being older at the time of illness onset.

DISCUSSION/CONCLUSIONS

SQoL can be high and changeable. While symptomology and illness insight may affect SQoL self-appraisals at single points in time, only age of illness onset was connected with improving SQoL. Thus, public health measures to delay illness onset are important. In addition, care about the distinction between HRQoL and SQoL in study design and choice of measures is necessary and will depend on the purpose and context.

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.

Effects of independent versus dependent stressful life events on major symptom domains of schizophrenia

We evaluated two models to link stressful life events (SLEs) with the psychopathology of schizophrenia spectrum disorders (SSD). We separated SLEs into independent (iSLEs, unlikely influenced by one's behavior) and dependent (dSLEs, likely influenced by one's behavior). Stress-diathesis and stress generation models were evaluated for the relationship between total, i- and d- SLEs and the severity of positive, negative, and depressive symptoms in participants with SSD. Participants with SSD (n = 286; 196 males; age = 37.5 ± 13.5 years) and community controls (n = 121; 83 males; 35.4 ± 13.9 years) completed self-report of lifetime negative total, i- and d- SLEs. Participants with SSD reported a significantly higher number of total SLEs compared to controls (B = 1.11, p = 6.4 × 10-6). Positive symptom severity was positively associated with the total number of SLEs (β = 0.20, p = 0.001). iSLEs (β = 0.11, p = 0.09) and dSLEs (β = 0.21, p = 0.0006) showed similar association with positive symptoms (p = 0.16) suggesting stress-diathesis effects. Negative symptom severity was negatively associated with the number of SLEs (β = -0.19, p = 0.003) and dSLEs (β = -0.20, p = 0.001) but not iSLEs (β = -0.04, p = 0.52), suggesting stress generation effects. Depressive symptom severity was positively associated with SLEs (β = 0.34, p = 1.0 × 10-8), and the association was not statistically stronger for dSLEs (β = 0.33, p = 2.7 × 10-8) than iSLEs (β = 0.21, p = 0.0006), p = 0.085, suggesting stress-diathesis effects. The SLE - symptom relationships in SSD may be attributed to stress generation or stress-diathesis, depending on symptom domain. Findings call for a domain-specific approach to clinical intervention for SLEs in SSD.

Active Inference, Epistemic Value, and Uncertainty in Conceptual Disorganization in First-Episode Schizophrenia

BACKGROUND AND HYPOTHESIS

Active inference has become an influential concept in psychopathology. We apply active inference to investigate conceptual disorganization in first-episode schizophrenia. We conceptualize speech production as a decision-making process affected by the latent "conceptual organization"-as a special case of uncertainty about the causes of sensory information. Uncertainty is both minimized via speech production-in which function words index conceptual organization in terms of analytic thinking-and tracked by a domain-general salience network. We hypothesize that analytic thinking depends on conceptual organization. Therefore, conceptual disorganization in schizophrenia would be both indexed by low conceptual organization and reflected in the effective connectivity within the salience network.

STUDY DESIGN

With 1-minute speech samples from a picture description task and resting state fMRI from 30 patients and 30 healthy subjects, we employed dynamic causal and probabilistic graphical models to investigate if the effective connectivity of the salience network underwrites conceptual organization.

STUDY RESULTS

Low analytic thinking scores index low conceptual organization which affects diagnostic status. The influence of the anterior insula on the anterior cingulate cortex and the self-inhibition within the anterior cingulate cortex are elevated given low conceptual organization (ie, conceptual disorganization).

CONCLUSIONS

Conceptual organization, a construct that explains formal thought disorder, can be modeled in an active inference framework and studied in relation to putative neural substrates of disrupted language in schizophrenia. This provides a critical advance to move away from rating-scale scores to deeper constructs in the pursuit of the pathophysiology of formal thought disorder.

Genetic and Geographical Associations With Six Dimensions of Psychotic Experiences in Adolesence

BACKGROUND AND HYPOTHESIS

Large-scale epidemiological and genetic research have shown that psychotic experiences in the community are risk factors for adverse physical and psychiatric outcomes. We investigated the associations of six types of specific psychotic experiences and negative symptoms assessed in mid-adolescence with well-established environmental and genetic risk factors for psychosis.

STUDY DESIGN

Fourteen polygenic risk scores (PRS) and nine geographical environmental variables from 3590 participants of the Twins Early Development Study (mean age 16) were associated with paranoia, hallucinations, cognitive disorganization, grandiosity, anhedonia, and negative symptoms scales. The predictors were modeled using LASSO regularization separately (Genetic and Environmental models) and jointly (GE model).

STUDY RESULTS

In joint GE models, we found significant genetic associations of negative symptoms with educational attainment PRS (β = -.07; 95% CI = -0.12 to -0.04); cognitive disorganization with neuroticism PRS (β = .05; 95% CI = 0.03-0.08); paranoia with MDD (β = .07; 95% CI = 0.04-0.1), BMI (β = .05; 95% CI = 0.02-0.08), and neuroticism PRS (β = .05; 95% CI = 0.02-0.08). From the environmental measures only family SES (β = -.07, 95% CI = -0.10 to -0.03) and regional education levels (β = -.06; 95% CI = -0.09 to -0.02) were associated with negative symptoms.

CONCLUSIONS

Our findings advance understanding of how genetic propensity for psychiatric, cognitive, and anthropometric traits, as well as environmental factors, together play a role in creating vulnerability for specific psychotic experiences and negative symptoms in mid-adolescence.

Education and long-term outcomes in first episode psychosis: 10-year follow-up study of the PAFIP cohort

BACKGROUND

Lower levels of education have been associated with the development of psychosis. Investigating educational achievement in the first episode of psychosis (FEP) patients may shed light on the origins of the alterations and on the variability of outcomes in psychotic disorders.

METHODS

Education achievement was explored in a large sample (n = 659) of FEP patients enrolled in programa de atención a fases iniciales de psicosis (PAFIP), a research and assistance program conducted in Spain. Patients were stratified according to the Spanish educational system according to their attendance in primary (low), secondary (medium) or university studies (high). The three groups were compared on available premorbid, clinical and neuropsychological variables. A subgroup of patients (n = 209), comprising the 10-year follow-up PAFIP cohort, were again compared.

RESULTS

Overall, 49% and 37% of FEP patients had low and medium levels of education, respectively. In total, 13% of the patients with a higher level of education were more frequently women (64%) and older at illness onset (36 years old), reported better premorbid adjustment, presented less severe positive symptoms and better functioning; and showed higher premorbid intelligence quotient and better performance on all the explored cognitive domains. Ten years later the FEP patients in the medium- and high-education groups had good global functioning and a neurocognitive performance within the normal limits.

CONCLUSIONS

Higher education is associated with better initial conditions and more favourable outcomes after an FEP. Sharing this information with the world's educational systems is essential to targeting resources and designing innovative programs or strategies to compensate for student difficulties.

Hierarchical Symptom Components in Early Psychosis

BACKGROUND AND HYPOTHESIS

Quantitative models of psychopathology can empirically guide subclassification of heterogeneous clinical presentations such as psychosis; they are particularly well-equipped to capture the nuanced symptomatology observed in first-episode psychosis. As well, components may be better aligned with biological variables. The current study sought to confirm and extend knowledge of the hierarchical structure of psychosis symptoms in first-episode psychosis. Based on past hierarchical work, we hypothesized that a 4 component level would be most closely associated with longitudinal disability.

STUDY DESIGN

Participants with early-stage psychosis (N = 370) underwent clinical assessment with the scale for the assessment of positive symptoms (SAPS), scale for assessment of negative symptoms (SANS), and global assessment scale(GAS). A subset was assessed at 6 months (N = 221) and 1 year (N = 207). Hierarchical symptom components were extracted at 12 levels. The predictive utility of the components for global functioning was tested.

STUDY RESULTS

As predicted, the 4-component model (reality distortion, thought disorder, inexpressivity, apathy/asociality) provided a superior prediction of functioning over other levels of the hierarchy. Baseline apathy/asociality longitudinally predicted functioning beyond the shared variance of the components at 6 months (b = -4.83, t(216) = -5.37, p < .001, R2adj = 0.12) and 1-year (b = -4.49, t(202) = -4.38, p < .001, R2adj = 0.09).

CONCLUSIONS

The hierarchical structure of psychotic symptomatology and its external validity have been robustly established in independent, longitudinal first-episode psychosis samples. The established model incorporates multiple levels of granularity that can be flexibly applied based on the level that offers the greatest predictive utility for external validators.

Schizophrenia

Schizophrenia, characterised by psychotic symptoms and in many cases social and occupational decline, remains an aetiological and therapeutic challenge. Contrary to popular belief, the disorder is modestly more common in men than in women. Nor is the outcome uniformly poor. A division of symptoms into positive, negative, and disorganisation syndromes is supported by factor analysis. Catatonic symptoms are not specific to schizophrenia and so-called first rank symptoms are no longer considered diagnostically important. Cognitive impairment is now recognised as a further clinical feature of the disorder. Lateral ventricular enlargement and brain volume reductions of around 2% are established findings. Brain functional changes occur in different subregions of the frontal cortex and might ultimately be understandable in terms of disturbed interaction among large-scale brain networks. Neurochemical disturbance, involving dopamine function and glutamatergic N-methyl-D-aspartate receptor function, is supported by indirect and direct evidence. The genetic contribution to schizophrenia is now recognised to be largely polygenic. Birth and early life factors also have an important aetiological role. The mainstay of treatment remains dopamine receptor-blocking drugs; a psychological intervention, cognitive behavioural therapy, has relatively small effects on symptoms. The idea that schizophrenia is better regarded as the extreme end of a continuum of psychotic symptoms is currently influential. Other areas of debate include cannabis and childhood adversity as causative factors, whether there is progressive brain change after onset, and the long-term success of early intervention initiatives.

Loosening of Associations in Chronic Schizophrenia: Intersectionality of Verbal Learning, Negative Symptoms, and Brain Structure

In 1908, Bleuler proposed a unitary theory of schizophrenia, hypothesizing a “loosening of associations” as the central mechanism underlying disturbances in thinking, motivation, and affective expression. Here, we test Bleuler’s model in an archival sample of 79 healthy controls and 76 patients with chronic schizophrenia who had completed neuropsychological tests, including a measure of learning of novel word pairs, which was specifically selected to probe the structure and formation of new verbal associations. The patients also had positive and negative symptoms ratings, including measures of flat affect, anhedonia, and thought disorder. A subset of patients and controls (n = 39) had available prior archival 3-T magnetic resonance imaging (MRI) measures of prefrontal cortex (PFC) gray matter volumes. In relation to controls, patients showed evidence of a selective impairment in associative learning, independent of their overall reduced neuropsychological functioning. This neuropsychological impairment, in turn, correlated significantly with overall levels of negative but not positive symptoms, with the data showing an especially strong contribution of flattened emotional expression to verbal associate learning deficits in this patient sample. Moreover, the archival MRI data were consistent with prior research pointing to an important role of the PFC in supporting verbal associate learning and memory in patients and controls. Taken together, the current results provided evidence of a selective impairment in schizophrenia on a PFC-supported verbal associate learning and memory task, which was accompanied by negative symptoms in general, and flattened emotional expression, in particular.

Mismatch Negativity and P3a Impairment through Different Phases of Schizophrenia and Their Association with Real-Life Functioning

Impairment in functioning since the onset of psychosis and further deterioration over time is a key aspect of subjects with schizophrenia (SCZ). Mismatch negativity (MMN) and P3a, indices of early attention processing that are often impaired in schizophrenia, might represent optimal electrophysiological candidate biomarkers of illness progression and poor outcome. However, contrasting findings are reported about the relationships between MMN-P3a and functioning. The study aimed to investigate in SCZ the influence of illness duration on MMN-P3a and the relationship of MMN-P3a with functioning. Pitch (p) and duration (d) MMN-P3a were investigated in 117 SCZ and 61 healthy controls (HCs). SCZ were divided into four illness duration groups: ≤ 5, 6 to 13, 14 to 18, and 19 to 32 years. p-MMN and d-MMN amplitude was reduced in SCZ compared to HCs, independently from illness duration, psychopathology, and neurocognitive deficits. p-MMN reduction was associated with lower "Work skills". The p-P3a amplitude was reduced in the SCZ group with longest illness duration compared to HCs. No relationship between P3a and functioning was found. Our results suggested that MMN amplitude reduction might represent a biomarker of poor functioning in SCZ.

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.

Long term cortical thickness changes after a first episode of non- affective psychosis: The 10 year follow-up of the PAFIP cohort

Cortical thickness has been widely studied in individuals with schizophrenia and, in particular, first-episode psychosis. Abnormalities have been described, although there is, to date, a lack of consensus regarding changes across time and correlations with clinical and functional outcomes of the illness. One hundred and twenty-three first-episode psychosis patients and 74 healthy volunteers were subjected to magnetic resonance imaging scans and clinical and functional assessments by different scales at four consecutive visits during a 10 year follow-up period. Linear mixed effects models were applied to our data to compute cortical thickness changes over time in (1) schizophrenia patients versus healthy controls and (2) in patients with good versus poor functional outcome. The associations between cortical thickness percentage changes and clinical and functional status at 10 years were also assessed. The patients presented a thinner cortex than the controls at baseline (b's = -0.06; q ≤ 0.00023) with non-significant coefficients for the interaction term (follow-up time x group) (b's = -0.001; q ≥ 0.681). Poor functioning patients presented statistically significant coefficients for the interaction term (follow-up time x functionality) (left: b = -0.005, q = 0.019; right: b = -0.005, q = 0.022). In contrast, no correlations were found between cortical thickness measurements and clinical variables at 10 years. Overall, there were widespread thickness anomalies in first-episode psychosis patients across cortical regions that remained stable across time. Progressive thickness changes were related to patient functional outcomes, with progressive and steeper cortical thinning in patients with worse functional outcomes and a stabilization in those with better outcomes.

Dissecting the functional outcomes of first episode schizophrenia spectrum disorders: a 10-year follow-up study in the PAFIP cohort

BACKGROUND

The aim of the current study was to examine the heterogeneity of functional outcomes in first episode psychosis (FEP) patients and related clinical, neurocognitive and sociodemographic factors using a cluster analytic approach.

METHOD

A large sample of FEP patients (N = 209) was functionally reassessed 10 years after the first contact with an early intervention service. Multiple baseline, 3-year and 10-year follow-up variables were explored.

RESULTS

The cluster analysis emphasized the existence of six independent clusters of functioning: one cluster was normal overall (42.16%), two clusters showed moderate interpersonal (9.63%) or instrumental (12.65%) deficits, two clusters showed more severe interpersonal (12.05%) or interpersonal and instrumental (13.85%) deficits and there was a significantly overall impaired cluster (9.63%). Cluster comparisons showed that several baseline and follow-up factors were differentially involved in functional outcomes.

CONCLUSIONS

The current study demonstrated that distinct clusters of functioning in FEP patients can be identified. The fact that a variety of profiles was observed contributes to a better understanding of the nature of the heterogeneity characterizing FEP patients and has clinical implications for developing individualized treatment plans.

Understanding sex differences in long-term outcomes after a first episode of psychosis

While sex differences in schizophrenia have long been reported and discussed, long-term sex differences in outcomes among first episode of psychosis (FEP) patients in terms of the efficacy of Early Intervention Services (EIS) has been an under-explored area. A total of 209 FEP patients (95 females and 114 males) were reassessed after a time window ranging from 8 to 16 years after their first contact with an EIS program (PAFIP) that we will call the 10-year PAFIP cohort. Multiple clinical, cognitive, functioning, premorbid, and sociodemographic variables were explored at 1-year, 3-year and 10-year follow-ups. At first contact, females were older at illness onset, had higher premorbid adjustment and IQ, and were more frequently employed, living independently, and accompanied by a partner and/or children. Existence of a schizophrenia diagnosis, and cannabis and alcohol consumption were more probable among men. During the first 3 years, women showed a significantly better response to minimal antipsychotic dosages and higher rates of recovery than men (50% vs. 30.8%). Ten years later, more females continued living independently and had partners, while schizophrenia diagnoses and cannabis consumption continued to be more frequent among men. Females also presented a lower severity of negative symptoms; however, functionality and recovery differences did not show significant differences (46.7% vs. 34.4%). Between the 3- and 10-year follow-up sessions, an increase in dosage of antipsychotics was observed. These results suggest that the better outcomes seen among women during the first 3 years (while they were treated in an EIS) were in the presence of more favourable premorbid and baseline characteristics. After an average period of 10 years, with the only difference being in negative symptoms course, outcomes for women approximated those of men, drawing particular attention to the increase in dosage of antipsychotic medication once FEP patients were discharged from the EIS program towards community-based services. These findings help to pose the question of whether it is advisable to target sexes and lengthen EIS interventions.

Cognitive Impairment and Diminished Neural Responses Constitute a Biomarker Signature of Negative Symptoms in Psychosis

The treatment of negative symptoms (NS) in psychosis represents an urgent unmet medical need given the significant functional impairment it contributes to psychosis syndromes. The lack of progress in treating NS is impacted by the lack of known pathophysiology or associated quantitative biomarkers, which could provide tools for research. This current analysis investigated potential associations between NS and an extensive battery of behavioral and brain-based biomarkers in 932 psychosis probands from the B-SNIP database. The current analyses examined associations between PANSS-defined NS and (1) cognition, (2) pro-/anti-saccades, (3) evoked and resting-state electroencephalography (EEG), (4) resting-state fMRI, and (5) tractography. Canonical correlation analyses yielded symptom-biomarker constructs separately for each biomarker modality. Biomarker modalities were integrated using canonical discriminant analysis to summarize the symptom-biomarker relationships into a "biomarker signature" for NS. Finally, distinct biomarker profiles for 2 NS domains ("diminished expression" vs "avolition/apathy") were computed using step-wise linear regression. NS were associated with cognitive impairment, diminished EEG response amplitudes, deviant resting-state activity, and oculomotor abnormalities. While a connection between NS and poor cognition has been established, association to neurophysiology is novel, suggesting directions for future mechanistic studies. Each biomarker modality was related to NS in distinct and complex ways, giving NS a rich, interconnected fingerprint and suggesting that any one biomarker modality may not adequately capture the full spectrum of symptomology.

Psychiatric symptoms and quality of life in older adults with schizophrenia spectrum disorder: results from a multicenter study

The severity of psychopathology has a strong negative impact on quality of life (QoL) among older adults with schizophrenia spectrum disorder. However, because these subjects generally experience multiple psychiatric symptoms, it remains unclear whether decreased QoL in this population is due to specific symptoms (e.g., hallucinations), specific dimensions of psychopathology (e.g., negative symptoms), a general psychopathology dimension representing the shared effect across all psychiatric symptoms, or a combination of these explanations. Data were derived from the Cohort of individuals with Schizophrenia Aged 55 years or more (CSA) study, a large (N = 353) multicenter sample of older adults with schizophrenia spectrum disorder recruited from French public-sector psychiatric departments. We used structural equation modeling to examine the shared and specific effects of psychiatric symptoms on QoL, while adjusting for sociodemographic characteristics, general medical conditions, global cognitive functioning and psychotropic medications. Psychiatric symptoms and QoL were assessed face-to-face by psychiatrists using the Brief Psychiatric Rating Scale (BPRS) and the Quality of Life Scale (QLS). Among older adults with schizophrenia spectrum disorder, effects of psychiatric symptoms on QoL were exerted mostly through a general psychopathology dimension (β = - 0.43, p < 0.01). Negative symptom dimension had an additional negative effect on QoL beyond the effect of that factor (β = - 0.28, p < 0.01). Because psychiatric symptoms affect QoL mainly through two dimensions of psychopathology, i.e., a general psychopathology dimension and a negative symptom dimension, mechanisms underlying those dimensions should be considered as promising targets for therapeutic interventions to substantially improve quality of life of this vulnerable population.

Brain grey matter abnormalities in first episode non-affective psychosis patients with suicidal behaviours: The role of neurocognitive functioning

BACKGROUND

Suicide is one of the leading causes of premature death in first-episode psychosis (FEP) patients. The understanding of suicidal behaviour (SB) is limited, and new and integrative approaches focusing on the likely relationship of the biological and cognitive features of SB in the early phases of psychosis are warranted. We aimed to study the relationship of brain grey matter anomalies and cognitive functioning with SB or suicidal risk in a large sample of non-affective FEP patients.

METHODS

We used a voxel-based morphometry analysis in 145 FEP patients to investigate the pattern of structural brain abnormalities related to SB. In addition, bivariate and multivariate analyses were performed to explore the relationship between cognitive functioning and SB.

RESULTS

A reduction in grey matter volume in the frontal area, temporal gyrus, precuneus, uncus, amygdala, left cuneus and subcallosal gyrus as well as a marked regional volume reduction in the right hemisphere was linked with the presence of SB. Additionally, worse global cognitive functioning and living in urban areas were identified as suicide risk factors.

CONCLUSIONS

This study provides some insights about the brain abnormalities associated with SB in FEP patients. Specifically, the areas reported are involved in important functions related to SB, such as impulsivity, problem solving or responses to pain. Thus, the results confirm the relevant role of cognitive functioning on SB.

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.

The synergetic effect of childhood trauma and recent stressful events in psychosis: associated neurocognitive dysfunction

BACKGROUND

A higher incidence of childhood trauma (CT) has been reported in first episode of psychosis (FEP). There is, however, a lack of knowledge about the synergetic effect between CT and recent stressful events (RSE).

METHODS

Information on specific types of CT (under 17 years) and RSE (within the past 3 years) was available for 290 FEP patients and 52 healthy controls (HC). Cognitive function at baseline was assessed through a comprehensive neuropsychological test battery.

RESULTS

While 45.2% of FEP patients and 25% of HC reported at least one CT event, 62.7% of FEP and 21.2% of HC reported an RSE. Meanwhile, 36.2% of FEP patients and 9.6% of HC encountered both childhood and recent stressful events. The patients that just reported CT showed normality in all but the verbal memory cognitive domain; those with additive CT and RSE presented worse general cognitive function, specifically on working memory, processing speed, and executive function. RSE and general cognitive dysfunction were significant determinants of psychosis onset.

CONCLUSIONS

These results support a synergetic influence of trauma and stressful events on brain function and allow a better understanding of mediators for psychotic disorders useful in the design of specific strategies based on stress-targeted therapies.

Stopping cannabis use benefits outcome in psychosis: findings from 10-year follow-up study in the PAFIP-cohort

OBJECTIVE

To examine the long-term (up to 10 years) patterns related to cannabis use in a sample of patients with first episode of psychosis (FEP) and the effect that consumption might have on clinical, functioning, and neurocognition at long-term.

METHODS

Cannabis use was described in 209 FEP patients. Patients were divided into three groups according to cannabis use: persistent users, ex-users, and never-users. Groups were longitudinally (baseline and 10-year follow-up) compared on clinical, functional, and cognitive variables.

RESULTS

Clinical differences at 10-year follow-up were observed between persistent cannabis users and the other two groups (ex-users and never-users), showing persistent users more severe symptoms (BPRS: x²  = 15.583, P ≤ 0.001; SAPS: x²  = 12.386, P = 0.002) and poorer functionality (DAS: x²  = 6.067, P = 0.048; GAF: x²  = 6.635, P = 0.033). Patients who stopped cannabis use prior to the reassessment showed a similar pattern to those who had never consumed.

CONCLUSION

The use of cannabis could negatively affect the evolution of the psychotic disorder. Perhaps the negative effects caused by cannabis use could be reversed with the cessation of consumption. It is necessary to make an effort in the intervention toward an early withdrawal from the use of cannabis, since this could play an important role in the prognosis of the disease.

Development and validation of the DISCUS scale: A reliable short measure for assessing experienced discrimination in people with mental health problems on a global level

BACKGROUND

The Discrimination and Stigma Scale (DISC-12) was specifically developed to measure experienced and anticipated discrimination reported by people with mental health problems. However, the length of the DISC-12 may represent a disadvantage especially in country settings with limited human capacity and infrastructure. The purpose of the study was to develop a short version of DISC-12 (DISCUS) to address these limitations.

METHODS

Data from 1087 participants with major depressive disorder and 732 patients with schizophrenia were collected as part of two research network studies across 35 countries - Anti Stigma Programme European Network (ASPEN) and International Study of Discrimination and Stigma (INDIGO). We used a Meta Exploratory Factor Analysis (meta-EFA) and a Multiple Causes Multiple Indicators (MIMIC) Model to reduce the number of items in the DISC-12 scale. The validity and reliability of the reduced scale (DISCUS) was tested in 202 people with the full spectrum of mental disorders recruited in a cross-sectional study conducted in South London. Psychometric validation for the reduced scale used confirmatory factor analysis and measures of Cronbach's alpha and Pearson's correlation coefficient.

RESULTS

meta-EFA reduced twenty-one items to twelve items. An additional item was discarded with the use of the MIMIC model. The 11-item DISCUS demonstrated excellent reliability (Cronbach's alpha >0.85), good fit (Tucker Lewis Index and Comparative Fit Index value>0.9) and weak to moderate construct validity.

CONCLUSIONS

The DISCUS scale is a consistent and valid instrument to measure experienced and anticipated discrimination predominantly in personal and social relationships in global settings.

The Generative Adversarial Brain

The idea that the brain learns generative models of the world has been widely promulgated. Most approaches have assumed that the brain learns an explicit density model that assigns a probability to each possible state of the world. However, explicit density models are difficult to learn, requiring approximate inference techniques that may find poor solutions. An alternative approach is to learn an implicit density model that can sample from the generative model without evaluating the probabilities of those samples. The implicit model can be trained to fool a discriminator into believing that the samples are real. This is the idea behind generative adversarial algorithms, which have proven adept at learning realistic generative models. This paper develops an adversarial framework for probabilistic computation in the brain. It first considers how generative adversarial algorithms overcome some of the problems that vex prior theories based on explicit density models. It then discusses the psychological and neural evidence for this framework, as well as how the breakdown of the generator and discriminator could lead to delusions observed in some mental disorders.

Network Analysis Reveals the Latent Structure of Negative Symptoms in Schizophrenia

Prior studies using exploratory factor analysis provide evidence that negative symptoms are best conceptualized as 2 dimensions reflecting diminished motivation and expression. However, the 2-dimensional model has yet to be evaluated using more complex mathematical techniques capable of testing structure. In the current study, network analysis was applied to evaluate the latent structure of negative symptoms using a community-detection algorithm. Two studies were conducted that included outpatients with schizophrenia (SZ; Study 1: n = 201; Study 2: n = 912) who were rated on the Brief Negative Symptom Scale (BNSS). In both studies, network analysis indicated that the 13 BNSS items divided into 6 negative symptom domains consisting of anhedonia, avolition, asociality, blunted affect, alogia, and lack of normal distress. Separation of these domains was statistically significant with reference to a null model of randomized networks. There has been a recent trend toward conceptualizing the latent structure of negative symptoms in relation to 2 distinct dimensions reflecting diminished expression and motivation. However, the current results obtained using network analysis suggest that the 2-dimensional conceptualization is not complex enough to capture the nature of the negative symptom construct. Similar to recent confirmatory factor analysis studies, network analysis revealed that the latent structure of negative symptom is best conceptualized in relation to the 5 domains identified in the 2005 National Institute of Mental Health consensus development conference (anhedonia, avolition, asociality, blunted affect, and alogia) and potentially a sixth domain consisting of lack of normal distress. Findings have implications for identifying pathophysiological mechanisms and targeted treatments.

Plasma prolactin levels are associated with the severity of illness in drug-naive first-episode psychosis female patients

Patients with schizophrenia frequently present hyperprolactinemia as a consequence of antipsychotic treatment. However, an increase in circulating prolactin levels has also been shown in patients without previous treatment. Our objective was to compare prolactin levels between antipsychotic-naive first-episode psychosis (AN-FEP) patients and healthy controls (HC). As part of an FEP program (Programa Asistencial Fases Iniciales de Psicosis [PAFIP]), 270 AN-FEP patients and 153 HC were eligible for this study. Serum prolactin levels were measured by an automated immunochemiluminescent assay. Subjects' sex and having an AN-FEP diagnosis both had an effect on prolactin levels, with higher levels in women than in men, and in AN-FEP patients than in HC. Moreover, plasma prolactin levels showed a negative correlation with the SAPS scores in AN-FEP female patients. AN-FEP patients have increased levels of prolactin, which might be stress-induced. This, together with the association of higher prolactin with a lower severity of the disease, suggests that prolactin might play a neuroprotective role, especially in women.

Cross-cultural Validation of the 5-Factor Structure of Negative Symptoms in Schizophrenia

OBJECTIVE

Negative symptoms are currently viewed as having a 2-dimensional structure, with factors reflecting diminished expression (EXP) and motivation and pleasure (MAP). However, several factor-analytic studies suggest that the consensus around a 2-dimensional model is premature. The current study investigated and cross-culturally validated the factorial structure of BNSS-rated negative symptoms across a range of cultures and languages.

METHOD

Participants included individuals diagnosed with a psychotic disorder who had been rated on the Brief Negative Symptom Scale (BNSS) from 5 cross-cultural samples, with a total N = 1691. First, exploratory factor analysis was used to extract up to 6 factors from the data. Next, confirmatory factor analysis evaluated the fit of 5 models: (1) a 1-factor model, 2) a 2-factor model with factors of MAP and EXP, 3) a 3-factor model with inner world, external, and alogia factors; 4) a 5-factor model with separate factors for blunted affect, alogia, anhedonia, avolition, and asociality, and 5) a hierarchical model with 2 second-order factors reflecting EXP and MAP, as well as 5 first-order factors reflecting the 5 aforementioned domains.

RESULTS

Models with 4 factors or less were mediocre fits to the data. The 5-factor, 6-factor, and the hierarchical second-order 5-factor models provided excellent fit with an edge to the 5-factor model. The 5-factor structure demonstrated invariance across study samples.

CONCLUSIONS

Findings support the validity of the 5-factor structure of BNSS-rated negative symptoms across diverse cultures and languages. These findings have important implications for the diagnosis, assessment, and treatment of negative symptoms.

Disorganisation, thought disorder and socio-cognitive functioning in schizophrenia spectrum disorders

BACKGROUND

Poor social cognition is prevalent in schizophrenia spectrum disorders. Some authors argue that these effects are symptom-specific and that socio-cognitive difficulties (e.g. theory of mind) are strongly associated with thought disorder and symptoms of disorganisation.AimsThe current review tests the strength of this association.

METHOD

We meta-analysed studies published between 1980 and 2016 that tested the association between social cognition and these symptoms in schizophrenia spectrum disorders.

RESULTS

Our search (PsycINFO, MEDLINE and Web of Science) identified 123 studies (N = 9107). Overall effect size as r = -0.313, indicating a moderate association between symptoms and social cognition. Subanalyses yielded a moderate association between symptoms and theory of mind (r = -0.349) and emotion recognition (r = -0.334), but smaller effect sizes for social perception (r = -0.188), emotion regulation (r = -0.169) and attributional biases (r = -0.143).

CONCLUSIONS

The association is interpreted within models of communication that highlight the importance of mentalisation and processing of partner-specific cues in conversational alignment and grounding.Declaration of interestsNone.

Assessing the application of latent class and latent profile analysis for evaluating the construct validity of complex posttraumatic stress disorder: cautions and limitations

Background: The diagnosis of complex posttraumatic stress disorder (CPTSD) has been suggested for inclusion in the 11th version of the International Classification of Diseases (ICD-11), with support for its construct validity coming from studies employing Latent Class Analysis (LCA) and Latent Profile Analysis (LPA). Objective: The current study aimed to critically evaluate the application of the techniques LCA and LPA as applied in previous studies to substantiate the construct validity of CPTSD. Method: Both LCA and LPA were applied systematically in one sample (n = 245), replicating the setup of previous studies as closely as possible. The interpretation of classes was augmented with the use of graphical visualization. Results: The LCA and LPA analyses indicated divergent results in the same dataset. LCA and LPA partially supported the existence of classes of patients endorsing different PTSD and CPTSD symptom patterns. However, further inspection of the results with scatterplots did not support a clear distinction between PTSD and CPTSD, but rather suggested that there is much greater variability in clinical presentations amongst adult PTSD patients than can be fully accounted for by either PTSD or CPTSD. Discussion: We argue that LCA and LPA may not be sufficient methods to decide on the construct validity of CPTSD, as different subgroups of patients are identified, depending on the statistical exact method used and the interpretation of the fit of different models. Additional methods, including graphical inspection should be employed in future studies.

The Latent Structure of Negative Symptoms in Schizophrenia

IMPORTANCE

Negative symptoms are associated with a range of poor clinical outcomes, and currently available treatments generally do not produce a clinically meaningful response. Limited treatment progress may be owing in part to poor clarity regarding latent structure. Prior studies have inferred latent structure using exploratory factor analysis, which has led to the conclusion that there are 2 dimensions reflecting motivation and pleasure (MAP) and diminished expressivity (EXP) factors. However, whether these conclusions are statistically justified remains unclear because exploratory factor analysis does not test latent structure. Confirmatory factor analysis (CFA) is needed to test competing models regarding the latent structure of a construct.

OBJECTIVE

To evaluate the fit of 4 models of the latent structure of negative symptoms in schizophrenia using CFA.

DESIGN, SETTING, AND PARTICIPANTS

Three cross-sectional studies were conducted on outpatients with schizophrenia who were rated on the 3 most conceptually contemporary measures: Scale for the Assessment of Negative Symptoms (SANS), Brief Negative Symptom Scale (BNSS), and Clinical Assessment Interview for Negative Symptoms (CAINS). Confirmatory factor analysis evaluated the following 4 models: (1) a 1-factor model; (2) a 2-factor model with EXP and MAP factors; (3) a 5-factor model with separate factors for the 5 domains of the National Institute of Mental Health consensus development conference (blunted affect, alogia, anhedonia, avolition, and asociality); and (4) a hierarchical model with 2 second-order factors reflecting EXP and MAP and 5 first-order factors reflecting the 5 consensus domains.

MAIN OUTCOMES AND MEASURES

Outcomes included CFA model fit statistics derived from symptom severity scores on the SANS, BNSS, and CAINS.

RESULTS

The study population included 860 outpatients with schizophrenia (68.0% male; mean [SD] age, 43.0 [11.4] years). Confirmatory factor analysis was conducted on each scale, including 268 patients for the SANS, 192 for the BNSS, and 400 for the CAINS. The 1- and 2-factor models provided poor fit for the SANS, BNSS, and CAINS as indicated by comparative fit indexes (CFIs) and Tucker Lewis indexes (TLIs) less than 0.950, RMSEAs that exceeded the 0.080 threshold, and WRMRs greater than 1.00. The 5-factor and hierarchical models provided excellent fit, with the 5-factor model being more parsimonious. The CFIs and TLIs met the 0.95 threshold and the 1.00 threshold for both factor models with all 3 measures. Interestingly, the RMSEAs for the 5-factor model and the hierarchical model fell under the 0.08 threshold for the BNSS and the CAINS but not the SANS.

CONCLUSIONS AND RELEVANCE

These findings suggest that the recent trend toward conceptualizing the latent structure of negative symptoms as 2 distinct dimensions does not adequately capture the complexity of the construct. The latent structure of negative symptoms is best conceptualized in relation to the 5 consensus domains. Implications for identifying pathophysiological mechanisms and targeted treatments are discussed.

The component structure of the scales for the assessment of positive and negative symptoms in first-episode psychosis and its dependence on variations in analytic methods

A secondary analysis was undertaken on Scales for the Assessment of Positive and Negative Symptoms (SAPS/SANS) data from 345 first-episode psychosis (FEP) patients gathered in the West London FEP study. The purpose of this study was to determine: (i) the component structure of these measures in FEP (primary analyses), and (ii) the dependence of any findings in these primary analyses on variations in analytic methods. Symptom ratings were exposed to data reduction methods and the effects of the following manipulations ascertained: (i) level of analysis (individual symptom vs. global symptom severity ratings), (ii) extraction method (principal component vs. exploratory factor analysis) and (iii) retention method (scree test vs. Kaiser criterion). Whilst global ratings level analysis rendered the classic triad of psychotic syndromes (positive, negative and disorganisation), symptom level analyses revealed a hierarchical structure, with 11 first-order components subsumed by three second-order components, which also mapped on to this syndrome triad. These results were robust across data reduction but not component retention methods, suggesting that discrepancies in the literature regarding the component structure of the SAPS/SANS partly reflect the level of analysis and component retention method used. Further, they support a hierarchical symptom model, the implications of which are discussed.

The dynamic relationship between insight and suicidal behavior in first episode psychosis patients over 3-year follow-up

Studies have established the high risk of suicide in first episode psychosis (FEP). Between 15% and 26% of FEP patients attempt suicide at least once before their first contact with psychiatric services and 2-5% die from suicide. Also, many patients with schizophrenia spectrum disorders lack insight into having a mental disorder. However, the relationship between insight changes and suicidal behavior in FEP remains poorly understood. In the present study information about suicidal behavior over a 3 years period was available on a cohort of 397 FEP patients, of whom 270 were assessed in the three dimensions of insight (into mental illness, the need for treatment, and the social consequences) at baseline, 1 and 3 years after treatment initiation. Survival analyses examined time to suicidal behavior in relation to (i) insight at baseline, (ii) the closest insight measure to the suicide attempt, and (iii) changes in insight during the follow-up. No associations were found between baseline insight dimensions and time to suicidal behavior. However, poor insight at the evaluation closest to the suicide attempt was associated with an increased risk of suicide. Stability of insight did not affect the risk of suicidal behavior, while changes in either direction were linked with an increased risk of suicidal behavior, particularly worsening insight. Insight in psychosis is a dynamic concept and we demonstrated the relationship between insight and suicide risk to be equally dynamic. Poor insight seems to increase the risk, especially when insight levels change. Repeated insight assessment to detect change from early psychosis may play a role in suicide prevention.

Dietary patterns and respiratory health in adults from nine European countries-Evidence from the GA2 LEN study

BACKGROUND

Dietary patterns defined using principal component analysis (PCA) offer an alternative to the analysis of individual foods and nutrients and have been linked with asthma and allergic disease. However, results have not been reproducible in different settings.

OBJECTIVE

To identify dietary patterns common to different European countries and examine their associations with asthma and allergic symptoms.

METHODS

In sixteen study centers in nine European countries, 3206 individuals aged 15-77 years completed a common, internationally validated, food frequency questionnaire and a respiratory symptoms questionnaire. The outcomes of interest were current asthma, asthma symptoms score (derived based on responses to 5 asthma symptom-related questions), atopy (positive skin prick test). Spirometry was used to estimate forced expiratory volume in 1 second (FEV₁ ), forced vital capacity (FVC), the FEV₁ /FVC, spirometric restriction (FVC below the lower limit of normal (<LLN)) and FEV₁ /FVC < LLN. A novel meta-analytic approach was used to identify dietary patterns using PCA and to examine associations with asthma and allergic symptoms.

RESULTS

Two dietary patterns emerged, generally correlating with the same foods in different countries: one associated with intake of animal proteins and carbohydrates; the other with fruit and vegetables. There was evidence that the former pattern was associated with a higher asthma score (RR 1.63, 95% CI: 1.33-2.01), current asthma (RR 2.03, 95% CI: 1.52-2.71), wheeze (RR 1.84, 95% CI: 1.30-2.60), atopic status (RR 1.68, 95% CI: 1.16-2.44) and with decreased lung function, including an FVC <LLN (RR 4.57, 95% CI: 2.27-9.21).

CONCLUSIONS AND CLINICAL RELEVANCE

Our findings suggest an increase in sensitisation to common allergens, an increase in asthma symptoms, and a reduction in lung function in those eating a diet rich in animal proteins and carbohydrates. We found little evidence of an association between these outcomes and eating a diet rich in fruits and vegetables.

Premorbid IQ subgroups in first episode non affective psychosis patients: Long-term sex differences in function and neurocognition

BACKGROUND

Low IQ has been associated with schizophrenia, even to the point of being posited as a possible causal factor for psychosis. However, individuals with normal and high IQ also develop psychotic illnesses. The aim of this study was to characterize premorbid IQ subgroups at first episode of psychosis (FEP).

METHODS

The study sample comes from a large epidemiological, 3-year longitudinal, intervention program on psychosis containing individuals living in a catchment area in Spain. Estimated premorbid IQ (epIQ) scores were used to build low (<90), normal (90-110) and high (>110) epIQ subgroups in samples of FEP patients (N=292) and healthy controls (N=199). The epIQ subgroups were compared in sociodemographic, neuropsychological, clinical and premorbid characteristics. Long-term functional and cognitive outcome, with a focus on sex differences, were also explored.

RESULTS

Low-epIQ was more frequently found in FEP patients (28.8%) than in healthy controls (14.6%). Low-epIQ patients were more likely to have worse premorbid adjustment, belong to low socioeconomic status families, have less years of education, and to be single, unemployed, and younger. They presented more severe impairments in processing speed, executive and global cognitive function. Female patients with low-epIQ showed better baseline function and more stable outcome than males.

CONCLUSIONS

Our results indicate that low premorbid IQ is a morbid manifestation, easily detected in a subgroup of FEP patients that predicts poorer outcome particularly in males. This perspective provides important information for the tailoring of subgroup-specific early intervention programs for psychosis.

Predicting suicidal behaviour after first episode of non-affective psychosis: The role of neurocognitive functioning

BACKGROUND

Suicide has been recognised as one of the major causes of premature death in psychosis. However, predicting suicidal behaviour (SB) is still challenging in the clinical setting and the association of neurocognition with SB in psychosis remains poorly understood. This study aimed to investigate the role of neurocognitive performance as predictor of SB. Also, we sought to explore differences in the evolution of clinical and neurocognitive functioning between participants with/without history of suicide attempts (SA) over follow-up period.

METHODS

The sample of the study is composed by 517 patients. Sociodemographic, clinical, functional and neurocognitive measures were evaluated at baseline as well as 1-year and 3 years after first episode of psychosis. Bivariate and multivariate analyses explored the influence of these variables as putative baseline predictors of SB. Repeated measures analyses of variance tested differences in clinical and neurocognitive outcomes at 1- and 3-year follow-up.

RESULTS

Global cognitive functioning (GCF) (OR = 1.83, 95% CI = 1.25-2.67) and severe depressive symptoms (OR = 1.17, 95% CI = 1.07-1.28) predicted SB. Longitudinal analyses revealed that patients with SB at follow-up presented with higher levels of remission in terms of positive psychotic symptoms and depression. In addition, those with a history of SB had worse GCF and visual memory than those without such antecedents.

CONCLUSIONS

GCF was found to be the most robust predictor of SB along with severe depressive symptomatology. Hence, poorer cognitive performance in FEP appears to emerge as a risk factor for suicidal behaviour from early stages of the illness and a comprehensive neurocognitive assessment may contribute to risk assessment.

Cognitive and psychopathology correlates of brain white/grey matter structure in severely psychotic schizophrenic inpatients

The brain structural correlates of cognitive and psychopathological symptoms within the active phase in severely psychotic schizophrenic inpatients have been rarely investigated. Twenty-eight inpatients with a DSM-5 diagnosis of Schizophrenia (SZ), admitted for acute psychotic decompensation, were assessed through a comprehensive neuropsychological and psychopathological battery. All patients underwent a high-resolution T1-weighted magnetic resonance imaging investigation. Increased psychotic severity was related to reduced grey matter volumes in the medial portion of the right superior frontal cortex, the superior orbitofrontal cortex bilaterally and to white matter volume reduction in the medial portion of the left superior frontal area. Immediate verbal memory performance was related to left insula and inferior parietal cortex volume, while long-term visuo-spatial memory was related to grey matter volume of the right middle temporal cortex, and the right (lobule VII, CRUS1) and left (lobule VI) cerebellum. Moreover, psychotic severity correlated with cognitive inflexibility and negative symptom severity was related to visuo-spatial processing and reasoning disturbances. These findings indicate that a disruption of the cortical-subcortical-cerebellar circuit, and distorted memory function contribute to the development and maintenance of psychotic exacerbation.

Duration of active psychosis and functional outcomes in first-episode non-affective psychosis

BACKGROUND

The duration of untreated psychosis (DUP) has been associated with negative outcomes in psychosis; however, few studies have focused on the duration of active psychotic symptoms after commencing treatment (DAT). In this study, we aimed to evaluate the effect of DUP and DAT on functional long-term outcomes (3 years) in patients with early psychosis.

METHODS

We evaluated the Scale for the Assessment of Positive Symptoms (SAPS) at frequent intervals for 3 years after presentation to determine the DAT for 307 individuals with first-episode psychosis together with DUP and clinical variables. The functional outcomes were assessed using the Disability Assessment Scale (DAS) at three years, and functional recovery was defined as minimal impairment and return to activity. Associated variables, DAT and DUP were included in logistic regression models to predict functional outcomes. Receiver operating characteristic curves and Youden's index were applied to assess the best cut-off values.

RESULTS

DAT, (Wald: 13.974; ExpB: 1.097; p < 0.001), premorbid adjustment, initial BPRS score, gender, age of onset and schizophrenia diagnosis were significant predictors of social functioning, whereas only premorbid adjustment (Wald: 11.383; ExpB:1.009), DAT (Wald: 4.850; ExpB: 1.058; p = 0.028) and education were significant predictors of recovery. The optimal cut-off of DAT for predicting social functioning was 3.17 months for DAT (sensitivity: 0.68; specificity: 0.64; Youden's index: 0.314).

CONCLUSIONS

DAT is strongly related to functional outcomes independent of the DUP period or other variables. As a modifiable variable, the reduction of the DAT should be considered a main focus of intervention from the onset of the illness to improve long-term outcomes.

Social cognition and self-other distinctions in neuropsychiatry: Insights from schizophrenia and Tourette syndrome

Impairments in social cognition may reflect dysfunction of disorder specific or disorder general mechanisms. Although cross-disorder comparison may prove insightful, few studies have compared social cognition in different neuropsychiatric disorders. Parallel investigation of schizophrenia and Tourette syndrome (TS) is encouraged by similarities including the presence of problematic social behavior, echophenomena, emotional dysregulation and dopamine dysfunction. Focusing on tests of social cognition administered in both disorders, this review aims to summarize behavioral, neurophysiological and neuroimaging findings, before exploring how these may contribute to clinical symptoms. Studies investigating social cognition (imitation, emotion recognition, and understanding of beliefs or intentions) in patients with schizophrenia or TS were identified through Web of Science and PubMed searches. Although findings indicate that social cognitive deficits are more apparent in schizophrenia, adults with TS can exhibit similar task performance to patients with paranoia. In both disorders, behavioral and neuroimaging findings raise the possibility of increased internal simulation of others' actions and emotions, in combination with a relative under-application of mentalizing. More specifically, dysfunction in neurobiological substrates such as temporo-parietal junction and inferior frontal gyrus may underlie problems with self-other distinctions in both schizophrenia and TS. Difficulties in distinguishing between actions and mental states linked to the self and other may contribute to a range of psychiatric symptoms, including emotional dysregulation, paranoia, social anhedonia and socially disruptive urges. Comparing different patient populations could therefore reveal common neuro-cognitive risk factors for the development of problematic social behaviors, in addition to markers of resilience, coping strategies and potential neuro-compensation mechanisms.

Validating dimensions of psychosis symptomatology: Neural correlates and 20-year outcomes

Heterogeneity of psychosis presents significant challenges for classification. Between 2 and 12 symptom dimensions have been proposed, and consensus is lacking. The present study sought to identify uniquely informative models by comparing the validity of these alternatives. An epidemiologic cohort of 628 first-admission inpatients with psychosis was interviewed 6 times over 2 decades and completed an electrophysiological assessment of error processing at year 20. We first analyzed a comprehensive set of 49 symptoms rated by interviewers at baseline, progressively extracting from 1 to 12 factors. Next, we compared the ability of resulting factor solutions to (a) account for concurrent neural dysfunction and (b) predict 20-year role, social, residential, and global functioning, and life satisfaction. A four-factor model showed incremental validity with all outcomes, and more complex models did not improve explanatory power. The 4 dimensions-reality distortion, disorganization, inexpressivity, and apathy/asociality-were replicable in 5 follow-ups, internally consistent, stable across assessments, and showed strong discriminant validity. These results reaffirm the value of separating disorganization and reality distortion, are consistent with recent findings distinguishing inexpressivity and apathy/asociality, and suggest that these 4 dimensions are fundamental to understanding neural abnormalities and long-term outcomes in psychosis. (PsycINFO Database Record

Cannabis use in male and female first episode of non-affective psychosis patients: Long-term clinical, neuropsychological and functional differences

BACKGROUND

Numerous studies show the existence of a high prevalence of cannabis use among patients with psychosis. However, the differences between men and women who debut with a first episode of psychosis (FEP) regarding cannabis use have not been largely explored. The aim of this study was to identify the specific sex factors and differences in clinical evolution associated with cannabis use.

METHOD

Sociodemographic characteristics at baseline were considered in our sample of FEP patients to find differences depending on sex and the use of cannabis. Clinical, functional and neurocognitive variables at baseline, 1-year, and 3-years follow-up were also explored.

RESULTS

A total of 549 patients, of whom 43% (N = 236) were cannabis users, 79% (N = 186) male and 21% (N = 50) female, were included in the study. There was a clear relationship between being male and being a user of cannabis (OR = 5.6). Cannabis users were younger at illness onset. Longitudinal analysis showed that women significantly improved in all three dimensions of psychotic symptoms, both in the subgroup of cannabis users and in the non-users subgroup. Conversely, subgroups of men did not show improvement in the negative dimension. In cognitive function, only men presented a significant time by group interaction in processing speed, showing a greater improvement in the subgroup of cannabis users.

CONCLUSION

Despite knowing that there is a relationship between cannabis use and psychosis, due to the high prevalence of cannabis use among male FEP patients, the results showed that there were very few differences in clinical and neurocognitive outcomes between men and women who used cannabis at the start of treatment compared to those who did not.

White matter integrity and symptom dimensions of schizophrenia: A diffusion tensor imaging study

Impaired fiber bundle connectivity between brain regions is a key neuropathological finding in schizophrenia. Symptom dimensions in schizophrenia can be clustered into factor models. Single syndromes have been related to grey and white matter brain structure alterations. We associated all core syndromes of schizophrenia in a single patient group with changes in white matter integrity. Diffusion weighted images (3T MRI) and SAPS/SANS scores were measured in 26 male patients and 26 healthy controls. First, group differences in fractional anisotropy (FA) were calculated with TBSS. Second, core symptom dimensions of schizophrenia were correlated with FA within these altered tracts. We found differences between groups in nine white matter tracts. Hallucinations were positively correlated with FA in the left uncinate fasciculus and left corticospinal tract. Ego-disturbances (passivity phenomena) showed a positive correlation with FA in the right anterior thalamic radiation. Positive formal thought disorders (FTD) corresponded negatively with FA in the right cingulum bundle. Negative symptoms were positively associated with the right anterior thalamic radiation and negatively with the right ventral cingulum bundle. For the first time, we analyzed the whole range of psychopathological factors in one schizophrenia patient group. We could validate our novel results for positive FTD and passivity phenomena by replicating findings for hallucinations and negative symptoms. Only those brain circuits which are most vulnerable at a given time during neurodevelopment are affected by a particular pathological impact (genetic, environmental). This scenario could explain the predominance of particular psychopathological syndromes related to specific white matter anomalies.

Diagnosis and neurocognitive profiles in first-episode non-affective psychosis patients

This study explored whether there are distinguishable neurocognitive profiles in diagnostic subgroups of first-episode non-affective psychosis (FEP) patients. Four hundred and eighty-seven individuals with diagnoses of non-affective psychosis disorders were evaluated 6 months after first contact with psychiatric services. Individuals with schizophrenia (n = 257), schizophreniform (n = 141), brief psychotic disorder (n = 54), and psychosis not otherwise specified (n = 35) were compared on baseline neuropsychological variables using analyses of variance and covariance with potential clinical, premorbid, and sociodemographic confounders. The brief psychotic disorder subgroup was the least impaired on global cognitive function, in particular when compared to the schizophrenia subgroup, and specifically on executive function, processing speed, and motor dexterity domains. However, with the exception of the processing speed domain, profile differences could be explained by sex, age, psychotic and negative symptoms, years of education, and premorbid IQ. These results suggest processing speed as a diagnostic marker for brief psychotic disorder in FEP patients. Further, there are quantitative and qualitative differences across the schizophrenia spectrum disorders subgroups, indicating different profiles with varying degrees of deficit.

Positive Allosteric Modulation of the Muscarinic M1 Receptor Improves Efficacy of Antipsychotics in Mouse Glutamatergic Deficit Models of Behavior

Current antipsychotics are effective in treating the positive symptoms associated with schizophrenia, but they remain suboptimal in targeting cognitive dysfunction. Recent studies have suggested that positive allosteric modulation of the M₁ muscarinic acetylcholine receptor (mAChR) may provide a novel means of improving cognition. However, very little is known about the potential of combination therapies in extending coverage across schizophrenic symptom domains. This study investigated the effect of the M₁ mAChR positive allosteric modulator BQCA [1-(4-methoxybenzyl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid], alone or in combination with haloperidol (a first-generation antipsychotic), clozapine (a second-generation atypical antipsychotic), or aripiprazole (a third-generation atypical antipsychotic), in reversing deficits in sensorimotor gating and spatial memory induced by the N-methyl-d-aspartate receptor antagonist, MK-801 [(5R,10S)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine]. Sensorimotor gating and spatial memory induction are two models that represent aspects of schizophrenia modeled in rodents. In prepulse inhibition (an operational measure of sensorimotor gating), BQCA alone had minimal effects but exhibited different levels of efficacy in reversing MK-801-induced prepulse inhibition disruptions when combined with a subeffective dose of each of the three (currently prescribed) antipsychotics. Furthermore, the combined effect of BQCA and clozapine was absent in M₁^-/- mice. Interestingly, although BQCA alone had no effect in reversing MK-801-induced memory impairments in a Y-maze spatial test, we observed a reversal upon the combination of BQCA with atypical antipsychotics, but not with haloperidol. These findings provide proof of concept that a judicious combination of existing antipsychotics with a selective M₁ mAChR positive allosteric modulator can extend antipsychotic efficacy in glutamatergic deficit models of behavior.

Evidence for Trait Related Theory of Mind Impairment in First Episode Psychosis Patients and Its Relationship with Processing Speed: A 3 Year Follow-up Study

This study aimed to confirm whether first-episode psychosis patients present a stable trait impairment in theory of mind (ToM) and to examine the potential relationship between ToM and clinical symptomatology and neurocognition. Patients with a first episode of psychosis (N = 160) and healthy controls (N = 159) were assessed with an extensive neuropsychological test battery, which included a mental state decoding task known as “The Reading the Mind in the Eyes” (Eyes test), at baseline and reassessed after 1 and 3 years. The clinical group performed below healthy controls on the Eyes test while not showing test-retest differences between baseline and follow-up administrations. Analyses revealed age, education and premorbid IQ as potential moderators. Poorer performance on the Eyes test was not linked to clinical symptomatology but was associated with greater neurocognitive deficit, particularly related to processing speed. The persistence of ToM deficits in patients suggests that there are trait related metalizing impairments in first episode psychosis. This study shows the influence of processing speed and moderator variables on efficient ToM.

Improving classification of psychoses

Psychosis has been recognised as an abnormal state in need of care throughout history and by diverse cultures. Present classifications of psychotic disorder remain based on the presence of specific psychotic symptoms, relative to affective and other symptoms, and their sequence and duration. Although extant diagnostic classifications have restricted validity, they have proven reliability and most clinicians and some patients find them useful. Moreover, these classifications have yet to be replaced by anything better. We propose that an expansion of the subgrouping approach inherent to classification will provide incremental improvement to present diagnostic constructs-as has worked in the rest of medicine. We also propose that subgroups could be created both within and across present diagnostic classifications, taking into consideration the potential value of continuous measures (eg, duration of psychotic symptoms and intelligence quotient). Health-care workers also need to work with service users and carers to develop and adapt approaches to diagnosis that are seen as helpful.

Suicidal behaviour in first-episode non-affective psychosis: Specific risk periods and stage-related factors

Suicide is a major cause of premature death in psychosis. Earlier stages have been associated with higher risk. However, such risk periods have not been specifically determined and risk factors for suicidal behaviour may change over those periods, which may have crucial implications for suicide prevention. The aim of this study was to determine and characterize the highest risk period for suicide in a representative sample of first-episode psychosis (FEP) patients. Suicidal behaviour prior to first presentation of psychosis and during a 3-year follow-up was examined in a sample of 397 individuals. Risk factors for suicidal behaviour during specific time periods were investigated and compared. The greatest suicide risk was found during the month before and 2 months after first contact with psychiatric services (i.e., 'early' attempts). Severity of depressive symptoms and cannabis use emerged as predominant risk factors across time. 'Early' attempters were characterized as being male, living in urban areas, having poor premorbid adjustment, requiring hospitalization, scoring higher on anxiety measures and unusual thought content than non-attempters. Greater suspiciousness and more severe depressive symptoms distinguished the 'late' attempters. In conclusion, there is a specific high risk period for suicide in FEP around the time of the first presentation. Early intervention programmes targeting phase-specific risk factors, particularly psychotic symptoms management and secondary depression prevention strategies may be useful for suicide prevention in psychosis.

No progression of the alterations in the cortical thickness of individuals with schizophrenia-spectrum disorder: a three-year longitudinal magnetic resonance imaging study of first-episode patients

BACKGROUND

Cortical thickness measurement offers an index of brain development processes. In healthy individuals, cortical thickness is reduced with increasing age and is related to cognitive decline. Cortical thinning has been reported in schizophrenia. Whether cortical thickness changes differently over time in patients and its impact on outcome remain unanswered.

METHOD

Data were examined from 109 patients and 76 healthy controls drawn from the Santander Longitudinal Study of first-episode schizophrenia for whom adequate structural magnetic resonance imaging (MRI) data were available (n = 555 scans). Clinical and cognitive assessments and MRIs were acquired at three regular time points during a 3-year follow-up period. We investigated likely progressive cortical thickness changes in schizophrenia during the first 3 years after initiating antipsychotic treatment. The effects of cortical thickness changes on cognitive and clinical variables were also examined along with the impact of potential confounding factors.

RESULTS

There were significant diagnoses × scan time interaction main effects for total cortical thickness (F 1,309.1 = 4.60, p = 0.033) and frontal cortical thickness (F 1,310.6 = 5.30, p = 0.022), reflecting a lesser thinning over time in patients. Clinical and cognitive outcome was not associated with progressive cortical changes during the early years of the illness.

CONCLUSIONS

Cortical thickness abnormalities do not unswervingly progress, at least throughout the first years of the illness. Previous studies have suggested that modifiable factors may partly account for cortical thickness abnormalities. Therefore, the importance of implementing practical actions that may modify those factors and improve them over the course of the illness should be highlighted.

Is the BPRS-5 subscale of the psychotic depression assessment scale a reliable screening tool for psychotic depression?: Results from the CRESCEND study

BACKGROUND

The detection of psychotic depression (PD) among patients with depressive disorders is important for both treatment and monitoring. Therefore, in continuation of our previous work, this study aimed to test the ability of the five-item Brief Psychiatric Rating Scale (BPRS-5) of the Psychotic Depression Assessment Scale (PDAS) in separating patients with psychotic depression from those with non-psychotic depression (non-PD) and to compare this discriminative validity to that of other item sets.

METHODS

A receiver operating characteristics curve was used to identify the optimal cut-off score of the BPRS-5 subscale for sensitive and specific distinction between PD and non-PD in a sample of 494 patients with depressive disorders (53 with PD and 441 with non-PD).

RESULTS

Using an optimal cut-off score of 1, the sensitivity and the specificity of the BPRS-5 subscale in detecting PD were 71.2% and 87.2%, respectively. The BPRS-5 outperformed other item sets of the PDAS and the positive symptom subscale of the BPRS in identifying patients with PD.

LIMITATIONS

The inter-rater reliability of the PDAS and the BPRS-5 subscale was not evaluated in this study.

CONCLUSIONS

The BPRS-5 subscale can be regarded as a more sensitive screening method for PD compared to other item sets from the PDAS and the BPRS. Hence, from a screening perspective, a positive score on any of the five symptoms of the BPRS-5 subscale (hallucinatory behavior, unusual thought content, suspiciousness, blunted affect, and emotional withdrawal) is indicative of PD, and should lead to more thorough diagnostic assessment.

A cross-sectional and longitudinal structural magnetic resonance imaging study of the post-central gyrus in first-episode schizophrenia patients

The post-central gyrus (PoCG) has received little attention in brain imaging literature. However, some magnetic resonance imaging (MRI) studies have detected the presence of PoCG abnormalities in patients with schizophrenia. Fifty-six first-episode schizophrenia patients, selected through the program of first-episode psychosis (PAFIP) and carefully assessed for dimensional psychopathology and cognitive functioning, and 56 matched healthy controls were scanned twice over 1-year follow-up. PoCG gray matter volumes were measured at both time-points and compared between the groups. Differences in volume change over time and the relationship between PoCG volume and clinical and cognitive variables were also investigated. The right PoCG volume was significantly smaller in patients than in controls at the 1-year follow-up; furthermore, it was significantly smaller in male patients compared with male controls, with no differences in female. Although there was no significant time by group interaction in the overall sample, a trend-level interaction was found for the right PoCG in males. This is the first study, as per our knowledge, to focus on PoCG in first-episode schizophrenia patients. The presence of PoCG abnormalities in the first year of schizophrenia suggests a possible contribution to the pathophysiology of the illness, probably as part of a more extensive network of abnormalities.

Childhood abuse in the etiological continuum underlying psychosis from first-episode psychosis to psychotic experiences

GOAL

The present study aimed to examine the prevalence of child abuse across the continuum of psychosis.

PATIENTS AND METHODS

The sample consisted of 198 individuals divided in three groups: (1) 48 FEP patients, (2) 77 individuals scoring high in Community Assessment of Psychic Experiences (CAPE), classified as "High CAPE" group and (3) 73 individuals scoring low, classified as "Low CAPE" group. Childhood abuse was assessed using self-report instruments. Chi(2) tests and logistic regression models controlling by sex, age and cannabis were used to perform three comparisons: (i) FEP vs. Low CAPE; (ii) FEP vs. High CAPE and (iii) High CAPE vs. Low CAPE.

RESULTS

The frequency of individuals exposed to childhood abuse for FEP, High CAPE and Low CAPE groups were 52.1%, 41.6% and 11%, respectively. FEP and High CAPE group presented significantly higher rates of childhood abuse compared to Low CAPE group, however, no significant differences were found between FEP and High CAPE groups regarding the frequency of childhood abuse.

CONCLUSION

There is an increasing frequency of childhood abuse from low subclinical psychosis to FEP patients. However, childhood abuse is equally common in FEP and at risk individuals.