Negative symptoms, past and present: a historical perspective and moving to DSM-5

Exploring negative symptoms heterogeneity in patients diagnosed with schizophrenia and schizoaffective disorder using cluster analysis

BACKGROUND

Dissecting the heterogeneity of schizophrenia may help foster progress in understanding its etiology and lay the groundwork for the development of new treatment options for primary or enduring negative symptoms (NS). In this regard, the present study aimed to: (1) to use cluster analysis to identify subgroups of Lebanese patients diagnosed with either schizophrenia or schizoaffective disorder based on NS clusters, and (2) to relate the statistically-derived subgroups to clinically relevant external validators (including measures if state and trait depression, stigma, insight, loneliness, social support).

METHOD

A total of 202 adult long-stay, chronic, and clinically remitted patients (166 diagnosed with schizophrenia and 36 with schizoaffective disorder) were enrolled. A cluster analysis approach was adopted to classify patients based on the five NS domains social withdrawal, emotional withdrawal, alogia, avolition and anhedonia.

RESULTS

A three-cluster solution was obtained based on unique NS profiles, and divided patients into (1) low NS (LNS; 42.6%) which characterized by the lowest mean scores in all NS domains, (2) moderate NS (MNS; 25.7%), and (3) high NS (HNS; 31.7%). Post-hoc comparisons showed that depression (state and trait), loneliness and social support could accurately distinguish the schizophrenia subgroups. Additionally, individuals in the HNS cluster had longer duration of illness, longer duration of hospitalization, and were given higher dosages of antipsychotic medication compared to those in the other clusters, but these differences did not achieve the statistical significance.

CONCLUSION

Findings provide additional support to the categorical model of schizophrenia by confirming the existence of three alternate subtypes based on NS. The determination of distinct NS subgroups within the broad heterogeneous population of people diagnosed with schizophrenia may imply that each subgroup possibly has unique underlying mechanisms and necessitates different treatment approaches.

Experiences of Everyday Life among Individuals with Co-Existence of Serious Mental Illness and Cancer-A Qualitative Systematic Literature Review

Daily life with severe mental health (SMI) and cancer comorbidity entails multiple challenges. The study aims to explore everyday life experiences among individuals with SMI and cancer comorbidity from the perspectives of patients, significant others, and involved healthcare professionals. The study is registered in PROSPERO (CRD42021259604). A qualitative systematic review was conducted through searches in the databases MEDLINE, CINAHL, PsychInfo, and Web of Sciences (last search 14 February 2023). Inclusion criteria were empirical qualitative research studies investigating experiences of healthcare and everyday life among persons living with SMI and who were subsequently diagnosed with cancer from the perspective of the individuals themselves, their significant others, and healthcare professionals involved in their care. Exclusion criteria: Literature reviews, quantitative studies, intervention studies, quantitative parts of mix-methods studies, non-English languages, persons <18 years, dementia/learning disabilities, diagnosed with anxiety/depression as a consequence of cancer. Seven articles, published between January 2011 and February 2023, were included and analysed through a thematic analysis. The PRISMA 2020 checklist guided the study. The results were presented in four themes: 'Navigating between different worlds and logics', 'Decision-making capacity depending on the assessor', 'Cancer must give way to severe mental illness or vice versa', and 'Significant others as a safety net'. Research about the everyday lives of persons with SMI and cancer comorbidities from patients' and relatives' perspectives is lacking and thus called for.

Negative symptoms in First-Episode Schizophrenia related to morphometric alterations in orbitofrontal and superior temporal cortex: the OPTiMiSE study

BACKGROUND

Negative symptoms are one of the most incapacitating features of Schizophrenia but their pathophysiology remains unclear. They have been linked to alterations in grey matter in several brain regions, but findings have been inconsistent. This may reflect the investigation of relatively small patient samples, and the confounding effects of chronic illness and exposure to antipsychotic medication. We sought to address these issues by investigating concurrently grey matter volumes (GMV) and cortical thickness (CTh) in a large sample of antipsychotic-naïve or minimally treated patients with First-Episode Schizophrenia (FES).

METHODS

T1-weighted structural MRI brain scans were acquired from 180 antipsychotic-naïve or minimally treated patients recruited as part of the OPTiMiSE study. The sample was stratified into subgroups with (N = 88) or without (N = 92) Prominent Negative Symptoms (PMN), based on PANSS ratings at presentation. Regional GMV and CTh in the two groups were compared using Voxel-Based Morphometry (VBM) and FreeSurfer (FS). Between-group differences were corrected for multiple comparisons via Family-Wise Error (FWE) and Monte Carlo z-field simulation respectively at p < 0.05 (2-tailed).

RESULTS

The presence of PMN symptoms was associated with larger left inferior orbitofrontal volume (p = 0.03) and greater CTh in the left lateral orbitofrontal gyrus (p = 0.007), but reduced CTh in the left superior temporal gyrus (p = 0.009).

CONCLUSIONS

The findings highlight the role of orbitofrontal and temporal cortices in the pathogenesis of negative symptoms of Schizophrenia. As they were evident in generally untreated FEP patients, the results are unlikely to be related to effects of previous treatment or illness chronicity.

Oscillatory Deficits in the Sub-Chronic PCP Rat Model for Schizophrenia Are Reversed by mGlu5 Receptor-Positive Allosteric Modulators VU0409551 and VU0360172

The cognitive deficits of schizophrenia are linked to imbalanced excitatory and inhibitory signalling in the prefrontal cortex (PFC), disrupting gamma oscillations. We previously demonstrated that two mGlu5 receptor-positive allosteric modulators (PAMs), VU0409551 and VU0360172, restore cognitive deficits in the sub-chronic PCP (scPCP) rodent model for schizophrenia via distinct changes in PFC intracellular signalling molecules. Here, we have assessed ex vivo gamma oscillatory activity in PFC slices from scPCP rats and investigated the effects of VU0409551 and VU0360172 upon oscillatory power. mGlu5 receptor, protein kinase C (PKC), and phospholipase C (PLC) inhibition were also used to examine ‘modulation bias’ in PAM activity. The amplitude and area power of gamma oscillations were significantly diminished in the scPCP model. Slice incubation with either VU0409551 or VU0360172 rescued scPCP-induced oscillatory deficits in a concentration-dependent manner. MTEP blocked the PAM-induced restoration of oscillatory power, confirming the requirement of mGlu5 receptor modulation. Whilst PLC inhibition prevented the power increase mediated by both PAMs, PKC inhibition diminished the effects of VU0360172 but not VU0409551. This aligns with previous reports that VU0409551 exhibits preferential activation of the phosphatidylinositol-3-kinase (PI3K) signalling pathway over the PKC cascade. Restoration of the excitatory/inhibitory signalling balance and gamma oscillations may therefore underlie the mGluR5 PAM-mediated correction of scPCP-induced cognitive deficits.

Longitudinal trajectories in negative symptoms and changes in brain cortical thickness: 10-year follow-up study

BACKGROUND

Understanding the evolution of negative symptoms in first-episode psychosis (FEP) requires long-term longitudinal study designs that capture the progression of this condition and the associated brain changes.

AIMS

To explore the factors underlying negative symptoms and their association with long-term abnormal brain trajectories.

METHOD

We followed up 357 people with FEP over a 10-year period. Factor analyses were conducted to explore negative symptom dimensionality. Latent growth mixture modelling (LGMM) was used to identify the latent classes. Analysis of variance (ANOVA) was conducted to investigate developmental trajectories of cortical thickness. Finally, the resulting ANOVA maps were correlated with a wide set of regional molecular profiles derived from public databases.

RESULTS

Three trajectories (stable, decreasing and increasing) were found in each of the three factors (expressivity, experiential and attention) identified by the factor analyses. Patients with an increasing trajectory in the expressivity factor showed cortical thinning in caudal middle frontal, pars triangularis, rostral middle frontal and superior frontal regions from the third to the tenth year after the onset of the psychotic disorder. The F-statistic map of cortical thickness expressivity differences was associated with a receptor density map derived from positron emission tomography data.

CONCLUSIONS

Stable and decreasing were the most common trajectories. Additionally, cortical thickness abnormalities found at relatively late stages of FEP onset could be exploited as a biomarker of poor symptom outcome in the expressivity dimension. Finally, the brain areas with less density of receptors spatially overlap areas that discriminate the trajectories of the expressivity dimension.

Progress and Pitfalls in Developing Agents to Treat Neurocognitive Deficits Associated with Schizophrenia

Cognitive impairments associated with schizophrenia (CIAS) represent a central element of the symptomatology of this severe mental disorder. CIAS substantially determine the disease prognosis and hardly, if at all, respond to treatment with currently available antipsychotics. Remarkably, all drugs presently approved for the treatment of schizophrenia are, to varying degrees, dopamine D₂/D₃ receptor blockers. In turn, rapidly growing evidence suggests the immense significance of systems other than the dopaminergic system in the genesis of CIAS. Accordingly, current efforts addressing the unmet needs of patients with schizophrenia are primarily based on interventions in other non-dopaminergic systems. In this review article, we provide a brief overview of the available evidence on the importance of specific systems in the development of CIAS. In addition, we describe the promising targets for the development of new drugs that have been used so far. In doing so, we present the most important candidates that have been investigated in the field of the specific systems in recent years and present a summary of the results available at the time of drafting this review (May 2022), as well as the currently ongoing studies.

The Cognitive Model of Negative Symptoms in Schizophrenia: A Hierarchical Component Model With PLS-SEM

The cognitive model of negative symptoms suggests that some dysfunctional beliefs mediate the relationship between neurocognitive deficits and negative symptoms and disability. This study tested the hypothesis that dysfunctional performance beliefs mediate neurocognitive deficits, negative symptoms, and disability. We used a hierarchal component model with 85 men patients diagnosed with chronic schizophrenia. Results showed a moderate to strong correlation between dysfunctional performance beliefs, neurocognitive deficits, negative symptoms, and disability. These results support the Hierarchal component model (HCM) of the cognitive model of negative symptoms. Our results indicated that the disability in schizophrenia is mediated through dysfunctional performance beliefs, neurocognitive deficits, and negative symptoms pathway. Further, dysfunctional performance beliefs have a crucial role in this pathway. Therefore, targeting this vicious cycle of dysfunctional beliefs can improve disability in patients with schizophrenia.

Ten-year trajectory and outcomes of negative symptoms of patients with first-episode schizophrenia spectrum disorders

This study explored the 10-year trajectories and outcomes of negative symptoms in patients with first-episode schizophrenia-spectrum disorder. Patients were from the historical control study comparing 10-year outcomes between standard care and early intervention services. A total of 298 patients were identified, 214 were successfully interviewed at 10-year follow-up for clinical and functional outcomes and 209 patients were included for final analyses. Information from clinical records were obtained systematically using standardized data entry forms. These information including negative symptoms, hospitalization and employment, monthly for year 1-3 and trimonthly for the year 4-10. Hierarchical cluster analysis was used to explore the 10-year negative symptom clusters. Demographics and early clinical characteristics related to the cluster memberships and different components of negative symptom at 10-year follow-up were further explored. The cluster analysis identified three longitudinal clusters of negative symptoms and 15% of patients were in the relapsed group. There was no difference in cluster membership between the intervention groups. Male gender and duration of hospitalizations in year four were found to be significant determinants of relapse negative symptoms. Lower education level, higher year-one negative symptom score and more months of unemployment during the first 3 years predicted overall negative symptoms at 10-year follow-up. Male gender was found to be a predictor only for avolition and anhedonia and duration of untreated psychosis only predicted anhedonia. These results highlighted the heterogeneity of longitudinal outcomes and the importance of personalized interventions.

Effects of Roluperidone (MIN-101) on two dimensions of the negative symptoms factor score: Reduced emotional experience and reduced emotional expression

BACKGROUND

Recent research has suggested that negative symptoms (NS) can be considered in terms of two different dimensions: reduced expression (expressive deficit) and reduced experience (experiential deficit). Roluperidone, a compound with high affinities for 5 HT2A and sigma2 receptors, has previously shown superiority over placebo on improving NS in a prospective study in patients with schizophrenia. The objective here is to explore the effect of roluperidone compared to placebo, on the 2 domains of the Negative Symptoms.

METHODS

This was a multi-national Phase 2b trial that enrolled 244 symptomatically stable patients with schizophrenia who had baseline scores ≥20 on the NS subscale of the PANSS. Patients were randomized to daily monotherapy with roluperidone 32 mg, roluperidone 64 mg, or placebo in a 1:1:1 ratio. All enrolled patients were Caucasian, and 137 (56%) were male. The 3 treatment groups were balanced on all demographic and illness-related baseline characteristics.

RESULTS

Both doses of roluperidone were superior to placebo on both domains: Reduced Experience (p ≤ .006 for the 32 mg; p ≤ .001 for the 64 mg) with persistent superiority from Week 2 for the 64 mg dose and Week 8 for the 32 mg dose; Reduced Expression (p ≤ .003 for 32 mg; p ≤ .001 for 64 mg) with similar persistence.

IMPLICATIONS

Both doses of roluperidone previously improved PANSS negative symptoms in general and demonstrated tolerability in stable schizophrenia patients. The post hoc analysis reported here found the drug to work on both the reduced emotional experience and reduced emotional expression sub-scales empirically derived from the PANSS.

Negative Symptoms in Schizophrenia: A Review and Clinical Guide for Recognition, Assessment, and Treatment

Schizophrenia is frequently a chronic and disabling disorder, characterized by heterogeneous positive and negative symptom constellations. The objective of this review was to provide information that may be useful for clinicians treating patients with negative symptoms of schizophrenia. Negative symptoms are a core component of schizophrenia that account for a large part of the long-term disability and poor functional outcomes in patients with the disorder. The term negative symptoms describes a lessening or absence of normal behaviors and functions related to motivation and interest, or verbal/emotional expression. The negative symptom domain consists of five key constructs: blunted affect, alogia (reduction in quantity of words spoken), avolition (reduced goal-directed activity due to decreased motivation), asociality, and anhedonia (reduced experience of pleasure). Negative symptoms are common in schizophrenia; up to 60% of patients may have prominent clinically relevant negative symptoms that require treatment. Negative symptoms can occur at any point in the course of illness, although they are reported as the most common first symptom of schizophrenia. Negative symptoms can be primary symptoms, which are intrinsic to the underlying pathophysiology of schizophrenia, or secondary symptoms that are related to psychiatric or medical comorbidities, adverse effects of treatment, or environmental factors. While secondary negative symptoms can improve as a consequence of treatment to improve symptoms in other domains (ie, positive symptoms, depressive symptoms or extrapyramidal symptoms), primary negative symptoms generally do not respond well to currently available antipsychotic treatment with dopamine D₂ antagonists or partial D₂ agonists. Since some patients may lack insight about the presence of negative symptoms, these are generally not the reason that patients seek clinical care, and clinicians should be especially vigilant for their presence. Negative symptoms clearly constitute an unmet medical need in schizophrenia, and new and effective treatments are urgently needed.

The relationship between depressive symptoms and negative symptoms in people with non-affective psychosis: a meta-analysis

The negative symptoms of psychosis and depressive symptomatology share several features, e.g. low motivation, apathy and reduced activity. Understanding the associations between these two sets of symptoms will support improved assessment and the development of interventions targeting these difficulties in people with psychosis. This is the first large systematic review and meta-analysis to quantify the relationship between these two categories of symptoms, as measured in studies to date. PsycInfo, Embase and Medline were systematically searched to identify eligible studies. Inclusion criteria ensured the studies measured both depression and negative symptoms using validated measures in a sample of over 8000 participants with non-affective psychosis diagnoses. The search led to 2020 records being screened and 56 included in the meta-analysis and review. Both meta-analyses and meta-regressions were conducted to explore the main effect and potential moderating variables. A clear pattern emerges showing that higher ratings of negative symptoms are associated with higher levels of depressive symptoms, with a small effect [standardised effect size = 0.19, p < 0.05). This did not vary greatly with the measures used (SES = 0.19-0.26) and was not moderated by demographic variables or quality ratings. Interestingly, higher depressive symptoms predict a significant relationship with co-occurring negative symptoms. However, higher negative symptoms predict that it is less likely there will be a relationship with co-occurring depressive symptoms. Heterogeneity was high across these analyses. The findings support the adoption of a symptom-specific approach to understanding the interplay between negative and depressive symptoms in psychosis, to improve assessment and intervention.

Spanish validation of the self-evaluation of negative symptoms scale SNS in an adolescent population

BACKGROUND

Negative symptoms (NS) may be observed in the general population in an attenuated form and in high-risk mental states. However, they have been less studied in the general population than positive symptoms, in spite of their importance at the insidious onset of schizophrenia and their appearance before positive symptoms. This study aimed to analyze the empirical structure of the Spanish version of the Self-Evaluation of Negative Symptoms (SNS) Scale and find its psychometric properties and invariance of measurement across sex and age in a sample of adolescents.

METHODS

The sample consisted of 4521 adolescents (53.6% female) from 11 to 18 years of age.

RESULTS

Confirmatory Factor Analysis of the SNS confirmed an internal structure of five first-order factors by the characteristic dimensions of NS: avolition, social withdrawal, diminished emotional range, anhedonia, alogia, and one second-order factor which includes the total NS score. Multi-group confirmatory factor analysis showed that the scale was invariant across sex and age. Total scale reliability was adequate. A strong relationship was found between the SNS with depressive symptomatology, moderate with ideas of reference and low with aberrant salience.

CONCLUSION

The results back use of the Spanish version of the SNS scale for detection of NS in the general population of adolescents.

Pharmacological treatment of negative symptoms in schizophrenia: update and proposal of a clinical algorithm

The clinical presentation of schizophrenia encompasses symptoms divided into three dimensions: positive, negative, and cognitive. Negative symptoms (NS), in particular, have a major impact on the quality of life of the affected subject, and, differing from positive symptoms, are often associated with a limited response to pharmacotherapy. To date, studies specifically investigating NS in schizophrenia are scant; therefore, proper selection of therapy for NS remains a major unmet medical need. Given the heterogeneity of the clinical presentation of schizophrenia, the treatment of NS, as well as therapy for other associated symptoms, should be largely individualized according to a patient's specific characteristics. In this paper, we review current knowledge on NS and construct a clinical algorithm for the treatment of schizophrenic conditions with pronounced NS. Overall, data from the literature suggest that second-generation antipsychotics, such as cariprazine and amisulpride, should be preferred over first-generation antipsychotics (FGAs), as they are associated with better functional outcomes and lower cognitive impairment. The combination of antipsychotics and antidepressants may also improve NS while addressing some affective disorders associated with schizophrenia; however, no clear information is available on the effects of this combination on primary NS or on the mechanism of action of the combination. In the proposed clinical algorithm, we suggest that cariprazine should be used as first-line treatment for patients with predominant NS, and that amisulpride should be considered as an alternative in cases of cariprazine failure. Further treatment lines may include the use of olanzapine and quetiapine, and add-on therapy with antidepressants.

Symptom recovery and relationship to structure of corpus callosum in individuals with an 'at risk mental state'

Previous studies have revealed that changes in sub-threshold psychotic symptoms observed in individuals with an 'at risk mental state' (ARMS) are associated with biological changes in the corpus callosum (CC). To elucidate the biological background for resilience against transition to psychosis, we investigated the relationship between CC structural changes and recovery of sub-threshold psychotic symptom in subjects with ARMS who did not develop psychosis (ARMS-N). Sixteen healthy controls and 42 ARMS (37 ARMS-N) subjects participated this study. The volumes of five sub-regions of the CC were analyzed using MRI. The sub-threshold psychotic symptoms of the ARMS were measured using the Scale of Prodromal Symptoms (SOPS). Imaging and symptoms were re-administered in the ARMS group 52 weeks later. Significant baseline volume differences in the mid-posterior CC, central CC and mid-anterior CC were found between the controls and the ARMS-N subjects. These findings suggest that biological abnormalities are present in a so-called "false-positive" group of individuals. For the ARMS-N subjects, improvement in negative symptoms significantly correlated with an increase in the volume of the central CC at follow-up. This finding may suggest that a neurobiological 'resilience' is associated with symptom recovery.

Are negative symptoms in schizophrenia a distinct therapeutic target?

Background and aims

The relationship between negative symptoms and cognition in schizophrenia is not clear, inconsistent findings have been reported by multiple authors and meta analyses. The aim of this study was to investigate the relationship between cognition and primary negative symptoms.

Methods

67 outpatients diagnosed with schizophrenia were evaluated using PANSS and the NSA-16 scale. Correlation and regression analyses were used in the present study to investigate the relationship between the primary negative symptoms and cognition.

Results

No relationship was found between the PANSS Cognitive factor and Negative factor, but when investigating the relationship of the Cognitive PANSS factor with the negative symptoms evaluated with the NSA-16 scale, it was shown that there is a significant association between cognition and motor retardation.

Conclusions

Our study reveals the relative independence of cognitive factor from the global negative domain of the psychopathology, even though the association with motor retardation was clear. These findings also support the need of using appropriate assessment tools in order to gain a more refined understanding of the phenomenology of schizophrenia.

Avolition-Apathy and White Matter Connectivity in Schizophrenia: Reduced Fractional Anisotropy Between Amygdala and Insular Cortex

The avolition/apathy domain of negative symptoms includes motivation- and pleasure-related impairments. In people with schizophrenia, structural and functional abnormalities were reported in key regions within the motivational reward system, including ventral-tegmental area (VTA), striatum (especially at the level of the nucleus accumbens, NAcc), orbitofrontal cortex (OFC), as well as amygdala (Amy) and insular cortex (IC). However, the association of the reported abnormalities with avoliton-apathy is still controversial. In the present study, we investigated white matter connectivity patterns within these regions, using a probabilistic analysis of diffusion tensor imaging (DTI) data, in male subjects with schizophrenia. Thirty-five male subjects with schizophrenia (SCZ) and 17 male healthy controls (HC) matched for age, underwent DTI. SCZ were evaluated using the Schedule for Deficit Syndrome (SDS), the Positive and Negative Syndrome Scale (PANSS), and the MATRICS Consensus Cognitive Battery (MCCB). Probabilistic tractography was applied to investigate pathways connecting the Amy and the NAcc with the OFC and IC. Reduced fractional anisotropy (FA) was observed in left Amy-ventral anterior IC connections, in SCZ compared with controls. This abnormality was negatively correlated with avolition/apathy but not with expressive deficit scores. SCZ showed also a reduced connectivity index between right NAcc and medial OFC, as compared with controls. Finally, the left NAcc-dorsal anterior IC connectivity index was negatively correlated with working memory scores. Our results indicate that only the avolition/apathy domain of negative symptoms is related to abnormal connectivity in the motivation-related circuits. The findings also demonstrate that distinct alterations underlie cognitive impairment and avolition/apathy.

Serum brain-derived neurotrophic factors in Taiwanese patients with drug-naïve first-episode schizophrenia: Effects of antipsychotics

OBJECTIVES

Brain-derived neurotrophic factors (BDNF) are known to be related to the psychopathology of schizophrenia. However, studies focussing on drug-naïve first-episode schizophrenia are still rare.

METHODS

Over a 5-year period, we investigated the serum BDNF levels in patients with first-episode drug-naïve schizophrenia and compared them to age- and sex-matched healthy controls. We also explored the association between antipsychotic doses, positive and negative syndrome scale (PANSS) scores, and serum BDNF levels before and after a 4-week antipsychotic treatment.

RESULTS

The baseline serum BDNF levels of 34 patients were significantly lower than those of the controls (df = 66, P = .001). Although the PANSS scores of 20 followed-up patients improved significantly after antipsychotic treatment, the elevation of the serum BDNF levels was not statistically significant (P = .386). In addition, Pearson's correlation test showed significant correlations between pre-treatment negative scale scores and percentage changes in BDNF (P = .002).

CONCLUSIONS

The peripheral BDNF levels in Taiwanese patients with drug-naïve first-episode schizophrenia, compared with healthy controls, did not elevate after antipsychotic treatment, and pre-treatment negative symptoms played a pivotal role in trajectories of serum BDNF levels. Large samples will be needed in future studies to verify these results.

Women and schizophrenia: planning for the future

The aim of this narrative review is to provide readers with a summary of the recent literature on women and schizophrenia and to address commonly asked questions about the role of gender in this illness. Important gender distinctions were found in the knowledge base around schizophrenia, particularly in the areas of symptom onset, hormonal and immune effects, and antipsychotic drug kinetics and their consequences. We also discuss and address commonly asked questions about gender and schizophrenia. This review concludes that gender differences influence the effectiveness of various treatments and need to be taken into account when planning comprehensive care services for individuals with schizophrenia.

Prediction of motivational impairment: 12-month follow-up of the randomized-controlled trial on extended early intervention for first-episode psychosis

BACKGROUND

Amotivation is prevalent in first-episode psychosis (FEP) patients and is a major determinant of functional outcome. Prediction of amotivation in the early stage of psychosis, however, is under-studied. We aimed to prospectively examine predictors of amotivation in FEP patients in a randomized-controlled trial comparing a 1-year extension of early intervention (Extended EI, 3-year EI) with step-down psychiatric care (SC, 2-year EI).

METHODS

One hundred sixty Chinese patents were recruited from a specialized EI program for FEP in Hong Kong after they have completed this 2-year EI service, randomly allocated to Extended EI or SC, and followed up for 12 months. Assessments on premorbid adjustment, onset profiles, baseline symptom severity and treatment characteristics were conducted. Data analysis was based on 156 subjects who completed follow-up assessments.

RESULTS

Amotivation at 12-month follow-up was associated with premorbid adjustment, allocated treatment condition, and levels of positive symptoms, disorganization, amotivation, diminished expression (DE) and depression at study intake. Hierarchical multiple regression analysis revealed that Extended EI and lower levels of DE independently predicted better outcome on 12-month amotivation.

CONCLUSION

Our findings indicate a potentially critical therapeutic role of an extended specialized EI on alleviating motivational impairment in FEP patients. The longer-term effect of Extended EI on amotivation merits further investigation.

Fine-mapping of antipsychotic response genome-wide association studies reveals novel regulatory mechanisms

Aim: Noncoding variation has demonstrated regulatory effects on disease treatment outcomes. This study investigated the potential functionality of previously implicated noncoding variants on schizophrenia treatment response. Materials & methods: Predicted regulatory potential of variation identified from antipsychotic response genome-wide association studies was determined. Prioritized variants were assessed for association(s) with treatment outcomes in a South African first episode schizophrenia cohort (n = 103). Results: Bioinformatic and association results implicated a relationship between regulatory variants, expression of MANBA, COL9A2 and NFKB1, and treatment response. Three SNPs were associated with poor outcomes (rs230493: p = 1.88 × 10-6; rs3774959: p = 1.75 × 10-5; and rs230504: p = 1.48 × 10-4). Conclusion: This study has thoroughly investigated previous GWAS to pinpoint variants that may play a causal role in poor schizophrenia treatment outcomes, and provides potential candidate genes for further study in the field of antipsychotic response.

Metabolic Abnormalities in the Hippocampus of Patients with Schizophrenia: A 3D Multivoxel MR Spectroscopic Imaging Study at 3T

BACKGROUND AND PURPOSE

Schizophrenia is well-known to be associated with hippocampal structural abnormalities. We used ¹H-MR spectroscopy to test the hypothesis that these abnormalities are accompanied by NAA deficits, reflecting neuronal dysfunction, in patients compared with healthy controls.

MATERIALS AND METHODS

Nineteen patients with schizophrenia (11 men; mean age, 40.6 ± 10.1 years; mean disease duration, 19.5 ± 10.5 years) and 11 matched healthy controls (5 men; mean age, 33.7 ± 10.1 years) underwent MR imaging and multivoxel point-resolved spectroscopy (TE/TR, 35/1400 ms) ¹H-MRS at 3T to obtain their hippocampal GM absolute NAA, Cr, Cho, and mIns concentrations. Unequal variance t tests and ANCOVA were used to compare patients with controls. Bilateral volumes from manually outlined hippocampal masks were compared by using unequal variance t tests.

RESULTS

Patients' average hippocampal GM Cr concentrations were 19% higher than that of controls, 8.7 ± 2.2 versus 7.4 ± 1.2 mmol/L (P < .05); showing no differences, concentrations in NAA were 8.8 ± 1.6 versus 8.7 ± 1.2 mmol/L; in Cho, 2.3 ± 0.7 versus 2.1 ± 0.3 mmol/L; and in mIns, 6.1 ± 1.5 versus 5.2 ± 0.9 (all P > .1). There was a positive correlation between mIns and Cr in patients (r = 0.57, P = .05) but not in controls. The mean bilateral hippocampal volume was ∼10% lower in patients: 7.5 ± 0.9 versus 8.4 ± 0.7 cm³ (P < .05).

CONCLUSIONS

These findings suggest that the hippocampal volume deficit in schizophrenia is not due to net loss of neurons, in agreement with histopathology studies but not with prior ¹H-MR spectroscopy reports. Elevated Cr is consistent with hippocampal hypermetabolism, and its correlation with mIns may also suggest an inflammatory process affecting some cases; these findings may suggest treatment targets and markers to monitor them.

Validation of the French Autism Spectrum Quotient scale and its relationships with schizotypy and Eysenckian personality traits

BACKGROUND

Autism and schizophrenia spectra were long considered distinct entities. Yet, recent studies emphasized overlapping clinical and personality features suggesting common mechanisms and liabilities. Independent notions, however, highlight that the two spectra oppose each other socially (positive schizotypal hyper-mentalism versus autistic hypo-mentalism).

METHODS

To clarify these relationships, we used data from 921 French-speaking Swiss undergraduates to firstly validate the French Autism Spectrum Questionnaire (AQ) identifying an optimal factor structure. Secondly, we assessed relationships between this AQ structure and schizotypic personality traits.

RESULTS

Results from correlational and principal component analyses replicated both overlapping and opposing relationships.

CONCLUSIONS

We conjecture that autistic traits opposing positive schizotypy represent autistic mentalizing deficits. We discuss implications of our findings relative to theories of autism and schizophrenia spectrum relationships.

Prefrontal neuronal integrity predicts symptoms and cognition in schizophrenia and is sensitive to genetic heterogeneity

Schizophrenia is a genetically complex syndrome with substantial inter-subject variability in multiple domains. Person-specific measures to resolve its heterogeneity could focus on the variability in prefrontal integrity, which this study indexed as relative rostralization within the anterior cingulate cortex (ACC). Twenty-two schizophrenia cases and 11 controls underwent rigorous diagnostic procedures, symptom assessments (PANSS, Deficit Syndrome Scale) and intelligence testing. All underwent multivoxel MRSI at 3T to measure concentrations of the neuronal-specific biomarker N-acetylaspartate (NAA) in all of the voxels of the ACC. The concentrations of NAA were separately calculated and then compared across the rostral and caudal subregions to generate a rostralization ratio, which was examined with respect to the study measures and to which cases carried a missense coding polymorphism in PTPRG, SCL39A13, TGM5, NTRK1 or ARMS/KIDINS220. Rostralization significantly differed between cases and controls (χ(2)=18.40, p<.0001). In cases, it predicted verbal intelligence (r=.469, p=.043) and trait negative symptoms (diminished emotional range (r=-.624, p=.010); curbed interests, r=-.558, p=.025). Rostralization was similar to controls for missense coding variants in TGM5 and was significantly greater than controls for the PTPRG variant carrier. This is the first study examining the utility of MRS metrics in describing pathological features at both group and person-specific levels. Rostralization predicted core illness features and differed based on which signaling genes were disrupted. While future studies in larger populations are needed, ACC rostralization appears to be a promising measure to reduce the heterogeneity of schizophrenia for genetic research and selecting cases for treatment studies.

Confirmatory Factor Analysis and Differential Relationships of the Two Subdomains of Negative Symptoms in Chronically Ill Psychotic Patients

Research suggests a two factor structure for negative symptoms in patients with psychotic disorders: social amotivation (SA) and expressive deficits (ED). Applying this two-factor structure in clinical settings may provide valuable information with regard to outcomes and to target treatments. We aimed to investigate 1) whether the factor structure is also supported in chronically ill patients with a psychotic disorder and 2) what the relationship is between these factors and functioning (overall functioning and living situation), depressive symptoms and quality of life. 1157 Patients with a psychotic disorder and a duration of illness of 5 years or more were included in the analysis (data selected from the Pharmacotherapy Monitoring Outcome Survey; PHAMOUS). A confirmatory factor analysis was performed using items of the Positive and Negative Syndrome Scale that were previously identified to reflect negative symptoms (N1-4, N6, G5, G7, G13, G16). Subsequently, regression analysis was performed on outcomes. The results confirmed the distinction between SA (N2, N4, G16) and ED (N1, N3, N6, G5, G7, G13) in chronically ill patients. Both factors were related to worse overall functioning as measured with the Health of the Nation Outcome Scales, ED was uniquely associated with residential living status. Higher scores for SA were associated with more depressive symptoms and worse quality of life. Thus, SA is most strongly related to level of social-emotional functioning, while ED are more related to living situation and thereby are indicative of level of everyday functioning. This subdivision may be useful for research purposes and be a valuable additional tool in clinical practice and treatment development.

Are negative symptoms really related to cognition in schizophrenia?

Previous studies have generally found a relationship between negative and cognitive symptoms in schizophrenia. The present study investigated the relationship between the 5 PANSS factors of a recent consensus model developed by NIMH researchers, and cognitive performance as assessed with the MATRICS Consensus Cognitive Battery (MCCB) in 80 patients with schizophrenia using correlation and regression analyses. The PANSS Cognitive factor showed a small to moderate significant association with MCCB Speed of processing, Working memory, Verbal learning, the Neurocognitive composite score, and the Overall composite score. Notably, however, no relationship was found between the PANSS Negative factor and any of the MCCB scores. The Positive, Excited and Depressed factors also did not show associations with the MCCB. These results highlight the need for refined assessment instruments and support the relative independence of cognition from other domains of psychopathology, including negative symptoms, in patients with schizophrenia.

The course of negative symptoms over the first five years of treatment: Data from an early intervention program for psychosis

BACKGROUND

Cross-sectional studies suggest that negative symptoms are constituted by separable domains of reduced expressiveness and reduced motivation, but there is little data on the longitudinal course of these symptoms. We examined evidence for differences in the course and correlates of these two domains in a prospective study of patients presenting with a first episode of psychosis.

METHODS

Of 132 patients who were followed up for five years, it was possible to monitor reduced expressiveness and motivation on a weekly basis for 127. Information on treatment delay, premorbid adjustment, intellectual functioning, anxiety, depression and psychosocial functioning were also collected.

RESULTS

Over the five year follow-up, symptoms of reduced motivation occurred in 95.3% of patients and reduced expressiveness in 68.5%; and deficits in motivation were more likely to be unremitting (15.7%) than expressive deficits (5.5%). There were differences in the correlates of the proportion of time each patient experienced symptoms of each domain. Depression, weeks of full time occupation and weeks on a disability pension were associated with both domains. Anxiety was associated only with diminished motivation. Lower performance IQ; extrapyramidal symptoms (EPS) and dysrhythmic EEG were associated only with proportion of time showing reduced expressiveness.

CONCLUSIONS

The prospective data support previous cross-sectional findings that, while these domains of negative symptoms are correlated, they do show differences in prevalence over time and in their correlates.

Learning from the past and looking to the future: Emerging perspectives for improving the treatment of psychiatric disorders

Modern neuropsychopharmacology commenced in the 1950s with the serendipitous discovery of first-generation antipsychotics and antidepressants which were therapeutically effective yet had marked adverse effects. Today, a broader palette of safer and better-tolerated agents is available for helping people that suffer from schizophrenia, depression and other psychiatric disorders, while complementary approaches like psychotherapy also have important roles to play in their treatment, both alone and in association with medication. Nonetheless, despite considerable efforts, current management is still only partially effective, and highly-prevalent psychiatric disorders of the brain continue to represent a huge personal and socio-economic burden. The lack of success in discovering more effective pharmacotherapy has contributed, together with many other factors, to a relative disengagement by pharmaceutical firms from neuropsychiatry. Nonetheless, interest remains high, and partnerships are proliferating with academic centres which are increasingly integrating drug discovery and translational research into their traditional activities. This is, then, a time of transition and an opportune moment to thoroughly survey the field. Accordingly, the present paper, first, chronicles the discovery and development of psychotropic agents, focusing in particular on their mechanisms of action and therapeutic utility, and how problems faced were eventually overcome. Second, it discusses the lessons learned from past successes and failures, and how they are being applied to promote future progress. Third, it comprehensively surveys emerging strategies that are (1), improving our understanding of the diagnosis and classification of psychiatric disorders; (2), deepening knowledge of their underlying risk factors and pathophysiological substrates; (3), refining cellular and animal models for discovery and validation of novel therapeutic agents; (4), improving the design and outcome of clinical trials; (5), moving towards reliable biomarkers of patient subpopulations and medication efficacy and (6), promoting collaborative approaches to innovation by uniting key partners from the regulators, industry and academia to patients. Notwithstanding the challenges ahead, the many changes and ideas articulated herein provide new hope and something of a framework for progress towards the improved prevention and relief of psychiatric and other CNS disorders, an urgent mission for our Century.

Negative symptoms of schizophrenia: clinical characteristics, pathophysiological substrates, experimental models and prospects for improved treatment

Schizophrenia is a complex and multifactorial disorder generally diagnosed in young adults at the time of the first psychotic episode of delusions and hallucinations. These positive symptoms can be controlled in most patients by currently-available antipsychotics. Conversely, they are poorly effective against concomitant neurocognitive dysfunction, deficits in social cognition and negative symptoms (NS), which strongly contribute to poor functional outcome. The precise notion of NS has evolved over the past century, with recent studies - underpinned by novel rating methods - suggesting two major sub-domains: "decreased emotional expression", incorporating blunted affect and poverty of speech, and "avolition", which embraces amotivation, asociality and "anhedonia" (inability to anticipate pleasure). Recent studies implicate a dysfunction of frontocortico-temporal networks in the aetiology of NS, together with a disruption of cortico-striatal circuits, though other structures are also involved, like the insular and parietal cortices, amygdala and thalamus. At the cellular level, a disruption of GABAergic-glutamatergic balance, dopaminergic signalling and, possibly, oxytocinergic and cannibinoidergic transmission may be involved. Several agents are currently under clinical investigation for the potentially improved control of NS, including oxytocin itself, N-Methyl-d-Aspartate receptor modulators and minocycline. Further, magnetic-electrical "stimulation" strategies to recruit cortical circuits and "cognitive-behavioural-psychosocial" therapies likewise hold promise. To acquire novel insights into the causes and treatment of NS, experimental study is crucial, and opportunities are emerging for improved genetic, pharmacological and developmental modelling, together with more refined readouts related to deficits in reward, sociality and "expression". The present article comprises an integrative overview of the above issues as a platform for this Special Issue of European Neuropsychopharmacology in which five clinical and five preclinical articles treat individual themes in greater detail. This Volume provides, then, a framework for progress in the understanding - and ultimately control - of the debilitating NS of schizophrenia.

Hyperschematia after right brain damage: a meaningful entity?

In recent years we reported three right-brain-damaged patients, who exhibited a left-sided disprortionate expansion of drawings, both by copying and from memory, contralateral to the side of the hemispheric lesion (Neurology, 67: 1801, 2006, Neurocase 14: 369, 2008). We proposed the term "hyperschematia" for such an expansion, with reference to an interpretation in terms of a lateral leftward distortion of the representation of extra-personal space, with a leftward anisometric expansion (relaxation) of the spatial medium. The symptom-complex shown by right-brain-damaged patients with "hyperschematia" includes: (1) a disproportionate leftward expansion of drawings (with possible addition of details), by copy and from memory (also in clay modeling, in one patient); (2) an overestimation of left lateral extent, when a leftward movement is required, associated in some patients with a perceptual underestimation; (3) unawareness of the disorder; (4) no unilateral spatial neglect. In most right-brain-damaged patients, left "hyperschematia" involves extra-personal space. In one patient the deficit was confined to a body part (left half-face: personal "hyperschematia"). The neural underpinnings of the disorder include damage to the fronto-temporo-parietal cortices, and subcortical structures in the right cerebral hemisphere, in the vascular territory of the middle cerebral artery. Here, four novel additional patients are reported. Finally, "hypeschematia" is reconsidered, in its clinical components, the underlying pathological mechanisms, as well as its neural underpinnings.