Factor structure of the Positive and Negative Syndrome Scale (PANSS) in Brazil: convergent validation of the Brazilian version

Urban distance to mental healthcare units and public transport increases duration of untreated psychosis in first-episode patients

BACKGROUND

There is a growing interest in environmental and social determinants of mental health. However, how distance to healthcare and public transportation affect illness is neglected in schizophrenia research. Here, we are interested in how the availability of mental healthcare and the ways to reach it may be associated with psychosis.

AIMS

We aim to investigate the association between distances to healthcare units and subway stations and duration of untreated psychosis (DUP) and greater initial severity in an antipsychotic-naïve first episode of psychosis (FEP) sample.

METHOD

Using 212 untreated FEP patients' data, we calculated the distances from their residences to the places of interest. Diagnoses comprehended schizophrenia spectrum disorders, depressive and bipolar affective disorders, and substance-induced disorders. Linear regressions were performed with distances as independent variables, DUP and Positive and Negative Syndrome Scale (PANSS) scores as dependent variables.

RESULTS

Longer distance to emergency mental healthcare was related to longer DUP (95% CI: p = .034, B = 0.152) and higher total PANSS (95% CI: p = .007, B = 0.0189); longer distance to community mental healthcare units was related to longer DUP (95% CI: p = .004, B = 0.0204) and higher total PANSS (95% CI: p = .030, B = 0.152). Moreover, a longer distance to the closest subway station predicted longer DUP (95% CI: p = .019, B = 0.170).

CONCLUSION

Our results indicate that poor healthcare access is related to longer DUP and higher initial PANSS scores. Future research should investigate how investments in mental health access and actions to improve public transport access could impact DUP and treatment outcomes in psychosis patients.

Dysregulated noradrenergic response is associated with symptom severity in individuals with schizophrenia

Introduction

The locus coeruleus-noradrenaline (LC-NA) system is involved in a wide range of cognitive functions and may be altered in schizophrenia. A non-invasive method to indirectly measure LC activity is task-evoked pupillary response. Individuals with schizophrenia present reduced pupil dilation compared to healthy subjects, particularly when task demand increases. However, the extent to which alteration in LC activity contributes to schizophrenia symptomatology remains largely unexplored. We aimed to investigate the association between symptomatology, cognition, and noradrenergic response in individuals with schizophrenia.

Methods

We assessed task-evoked pupil dilation during a pro- and antisaccade task in 23 individuals with schizophrenia and 28 healthy subjects.

Results

Both groups showed similar preparatory pupil dilation during prosaccade trials, but individuals with schizophrenia showed significantly lower pupil dilation compared to healthy subjects in antisaccade trials. Importantly, reduced preparatory pupil dilation for antisaccade trials was associated with worse general symptomatology in individuals with schizophrenia.

Discussion

Our findings suggest that changes in LC-NA activity - measured by task-evoked pupil dilation - when task demand increases is associated with schizophrenia symptoms. Interventions targeting the modulation of noradrenergic responses may be suitable candidates to reduce schizophrenia symptomatology.

Psychometric properties of the mini international neuropsychiatric interview (MINI) psychosis module: a Sub-Saharan Africa cross country comparison

BACKGROUND

The Mini International Neuropsychiatric Inventory 7.0.2 (MINI-7) is a widely used tool and known to have sound psychometric properties; but very little is known about its use in low and middle-income countries (LMICs). This study aimed to examine the psychometric properties of the MINI-7 psychosis items in a sample of 8609 participants across four countries in Sub-Saharan Africa.

METHODS

We examined the latent factor structure and the item difficulty of the MINI-7 psychosis items in the full sample and across four countries.

RESULTS

Multiple group confirmatory factor analyses (CFAs) revealed an adequate fitting unidimensional model for the full sample; however, single group CFAs at the country level revealed that the underlying latent structure of psychosis was not invariant. Specifically, although the unidimensional structure was an adequate model fit for Ethiopia, Kenya, and South Africa, it was a poor fit for Uganda. Instead, a 2-factor latent structure of the MINI-7 psychosis items provided the optimal fit for Uganda. Examination of item difficulties revealed that MINI-7 item K7, measuring visual hallucinations, had the lowest difficulty across the four countries. In contrast, the items with the highest difficulty were different across the four countries, suggesting that MINI-7 items that are the most predictive of being high on the latent factor of psychosis are different for each country.

CONCLUSIONS

The present study is the first to provide evidence that the factor structure and item functioning of the MINI-7 psychosis vary across different settings and populations in Africa.

Factor structure and item response of psychosis symptoms among Kenyan adults

BACKGROUND

The aim of this study was to evaluate the construct validity of the psychosis module of the Mini International Neuropsychiatric Interview version 7.0.2 (MINI-7).

METHOD

We utilized data collected from 2738 participants with a primary psychotic or bipolar disorder. Participants were drawn from two Kenyan sites of a large multi-center neuropsychiatric genetic study. The factor structure of the MINI-7 psychosis items were explored using confirmatory factor analyses (CFA) and Item Response Theory approach, for the full sample and by gender.

RESULTS

The CFA revealed that a 1-factor model provided adequate fit for the MINI-7 psychosis items for the full sample (x2 = 397.92, df = 35, p < .0001; RMSEA = 0.06; CFI = 0.92; TLI = 0.90) as well as for the female (x2 = 185.16.92, df = 35, p < .0001; RMSEA = 0.06; CFI = 0.93; TLI = 0.91) and male groups (x2 = 242.09, df = 35, p < .0001; RMSEA = 0.06; CFI = 0.92; TLI = 0.89). Item thresholds for the full sample, and female and male groups were highest for 'odd beliefs' (-1.42, -1.33, and -1.51 respectively) and lowest for 'visual hallucinations' (-0.03, -0.04, and -0.01 respectively).

LIMITATIONS

Our study used a hospital-based population, which may have excluded patients with milder psychotic symptoms. Findings may therefore not be generalizable to the community setting.

CONCLUSIONS

Our findings indicate good construct validity of the MINI-7 psychosis module, and provides support for use of the tool in diagnosing psychotic disorders in clinical settings in Kenya.

Identifying strategies to improve PANSS based dimensional models in schizophrenia: Accounting for multilevel structure, Bayesian model and clinical staging

BACKGROUND

Dimensional approaches can decompose a construct in a set of continuous variables, improving the characterization of complex phenotypes, such as schizophrenia. However, the five-factor model of the Positive and Negative Syndrome Scale (PANSS), the most used instrument in schizophrenia research, yielded poor fits in most confirmatory factor analysis (CFA) studies, raising concerns about its applications. Thus, we aimed to identify dimensional PANSS CFA models with good psychometric properties by comparing the traditional CFA with three methodological approaches: Bayesian CFA, multilevel modeling, and Multiple Indicators Multiple Causes (MIMIC) modeling.

METHODS

Clinical data of 700 schizophrenia patients from four centers were analyzed. We first performed a traditional CFA. Next, we tested the three techniques: 1) a Bayesian CFA; 2) a multilevel analysis using the centers as level; and 3) a MIMIC modeling to evaluate the impact of clinical staging on PANSS factors and items.

RESULTS

CFA and Bayesian CFA produced poor fit models. However, when adding a multilevel structure to the CFA model, a good fit model emerged. MIMIC modeling yielded significant differences in the factor structure between the clinical stages of schizophrenia. Sex, age, age of onset, and duration of illness did not significantly affect the model fit.

CONCLUSION

Our comparison of different CFA methods highlights the need for multilevel structure to achieve a good fit model and the potential utility of staging models (rather than the duration of illness) to deal with clinical heterogeneity in schizophrenia. Large prospective samples with biological data should help to understand the interplay between psychometrics concerns and neurobiology research.

Longitudinal invariance of the positive and negative syndrome scale negative dimension in antipsychotic naïve first-episode schizophrenia

AIM

Construct stability over time is required for reliable inference, but evidence regarding the longitudinal invariance of negative symptoms is still limited. Thus, we examined the longitudinal invariance of the negative dimension using the positive and negative syndrome scale (PANSS) in an antipsychotic-naïve first-episode schizophrenia sample at baseline and after 10 weeks.

METHODS

Our study was conducted at a specialized early intervention service. PANSS ratings were analysed for 138 patients, and two different models were specified and tested: a unidimensional and a two-correlated factor solution.

RESULTS

The unidimensional model fulfilled criteria for longitudinal invariance, whilst the two-correlated did not.

CONCLUSION

Our study provides support for the PANSS negative unidimensional model use to evaluate negative symptoms' longitudinal change following first-episode schizophrenia.

Aging biological markers in a cohort of antipsychotic-naïve first-episode psychosis patients

Schizophrenia is a severe and multifactorial disorder with an unknown causative pathophysiology. Abnormalities in neurodevelopmental and aging processes have been reported. Relative telomere length (RTL) and DNA methylation age (DMA), well-known biomarkers for estimating biological age, are both commonly altered in patients with schizophrenia compared to healthy controls. However, few studies investigated these aging biomarkers in first-episode psychosis (FEP) and in antipsychotic-naïve patients. To cover the existing gap regarding DMA and RTL in FEP and antipsychotic treatment, we aimed to verify whether those aging markers could be associated with psychosis and treatment response. Thus, we evaluated these measures in the blood of FEP antipsychotic-naïve patients and healthy controls (HC), as well as the response to antipsychotics after 10 weeks of treatment with risperidone. RTL was measured in 392 subjects, being 80 FEP and 312 HC using qPCR, while DMA was analyzed in a subset of 60 HC, 60 FEP patients (antipsychotic-naïve) and 59 FEP-10W (after treatment) using the "Multi-tissue Predictor"and the Infinium HumanMethylation450 BeadChip Kit. We observed diminished DMA and longer RTL in FEP patients before treatment compared to healthy controls, indicating a decelerated aging process in those patients. We found no statistical difference between responder and non-responder patients at baseline for both markers. An increased DMA was observed in patients after 10 weeks of treatment, however, after adjusting for blood cell composition, no significant association remained. Our findings indicate a decelerated aging process in the early phases of the disease.

Cognitive outcomes after tDCS in schizophrenia patients with prominent negative symptoms: Results from the placebo-controlled STARTS trial

Cognitive deficits and negative symptoms in schizophrenia are associated with poor functional outcomes and limited in terms of treatment. The Schizophrenia Treatment With Electric Transcranial Stimulation (STARTS) trial has shown efficacy of transcranial direct current stimulation (tDCS) for improving negative symptoms. In this secondary analysis, we investigate its effects on cognitive performance. In STARTS, a double-blinded, sham-controlled, randomized clinical trial, patients were treated with twice-daily, 20-min, 2-mA fronto-temporal tDCS over 5 days or sham-tDCS. In 90 patients, we evaluated the cognitive performance up to 12 weeks post-treatment. We found that active-tDCS showed no beneficial effects over sham-tDCS in any of the tests. Based on a 5-factor cognitive model, improvements of executive functions and delayed memory were observed in favor of sham-tDCS. Overall, the applied active-tDCS protocol, primarily designed to improve negative symptoms, did not promote cognitive improvement. We discuss possible protocol modification potentially required to increase tDCS effects on cognition. ClinicalTrials.gov identifier: NCT02535676.

Large-scale evaluation of the Positive and Negative Syndrome Scale (PANSS) symptom architecture in schizophrenia

Although the Positive and Negative Syndrome Scale (PANSS) is widely utilized in schizophrenia research, variability in specific item loading exist, hindering reproducibility and generalizability of findings across schizophrenia samples. We aim to establish a common PANSS factor structure from a large multi-ethnic sample and validate it against a meta-analysis of existing PANSS models. Schizophrenia participants (N = 3511) included in the current study were part of the Singapore Translational and Clinical Research Program (STCRP) and the Clinical Antipsychotic Trials for Intervention Effectiveness (CATIE). Exploratory Factor Analysis (EFA) was conducted to identify the factor structure of PANSS and validated with a meta-analysis (N = 16,171) of existing PANSS models. Temporal stability of the PANSS model and generalizability to individuals at ultra-high risk (UHR) of psychosis were evaluated. A five-factor solution best fit the PANSS data. These were the i) Positive, ii) Negative, iii) Cognitive/disorganization, iv) Depression/anxiety and v) Hostility factors. Convergence of PANSS symptom architecture between EFA model and meta-analysis was observed. Modest longitudinal reliability was observed. The schizophrenia derived PANSS factor model fit the UHR population, but not vice versa. We found that two other domains, Social Amotivation (SA) and Diminished Expression (DE), were nested within the negative symptoms factor. Here, we report one of the largest transethnic factorial structures of PANSS symptom domains (N = 19,682). Evidence reported here serves as crucial consolidation of a common PANSS structure that could aid in furthering our understanding of schizophrenia.

Impact of duration of untreated psychosis in short-term response to treatment and outcome in antipsychotic naïve first-episode psychosis

AIM

Duration of untreated psychosis (DUP) is one of the few potentially modifiable outcome predictors in psychosis. Previous studies have associated a longer DUP with a poor prognosis, but few of them were performed in countries with low and middle level of income. This study aimed to investigate the DUP in a Brazilian sample of antipsychotic-naïve first-episode psychosis (AN-FEP) patients and its association with clinical characteristics and treatment outcomes in a short-term follow-up.

METHODS

One hundred forty-five AN-FEP patients between 16 and 40 years were enrolled and were reassessed 10 weeks after risperidone treatment. We investigated the association between DUP and symptom severity, functionality and response to treatment, using the Positive and Negative Syndrome Scale (PANSS), the Clinical Global Impression-Severity Scale (CGI) and the Global Assessment of Functionality (GAF) scale. DUP was defined as the period between the onset of the first psychotic symptoms and the first effective antipsychotic treatment. For the analysis, we performed multivariate linear regressions.

RESULTS

The DUP's median was 61 days. At baseline, we did not find any significant association between DUP and clinical characteristics. After treatment, the longer DUP predicted worse positive and negative symptom dimensions, worse total PANSS, GAF and CGI scores and poorer response to treatment.

CONCLUSION

Our results showed that DUP is associated with worse outcomes after short treatment, but it does not modify the baseline clinical profile of the AN-FEP patients. Such results reinforce the need to develop early intervention strategies, reducing DUP.

Clinical profile in schizophrenia and schizoaffective spectrum: relation with unconjugated bilirubin in a prospective and controlled study with psychopathological and psychosocial variables

OBJECTIVE

Our objective was to assess unconjugated bilirubin (UCB) as biomarker for schizophrenia (SCZ) and schizoaffective (SAF) spectrums disorder (relapse vs. partial remission).

METHODS

Eighty-eight psychotic patients completed first assessment during relapse at ward admission, half with SCZ and half with SAF disorder. Forty-four acute bipolar patients were used as controls. After 12-month follow-up, we collected longitudinal protocol (laboratory, psychopathological, and psychosocial data) from 60 patients, half with SCZ and half with SAF disorder.

RESULTS

During psychotic relapse (N = 88), we found a statistically significant difference (analysis of variance [ANOVA]; p = .002), confirmed after post hoc multiple comparisons (Bonferroni) between SCZ (N = 44) and both SAF (N = 44; p = .05) and bipolar controls (N = 44; p = .05); a positive correlation (Pearson's r = .314) between UCB mean levels and Personal and Social Performance item (d) "disturbing and aggressive behaviors"; and a positive correlation (R2 = .223), with statistically significance (p = .008), between UCB mean levels and mean length of stay at the psychiatric ward in SAF patients who completed full protocol (N = 30). During partial remission (N = 60) we found: a statistically significant difference (ANOVA; p = .006), confirmed after post hoc multiple comparisons (Bonferroni) between SCZ (N = 30) and SAF (N = 30; p = .05); plus a negative correlation (Pearson's r = -.399) between UCB mean levels and Positive and Negative Syndrome Scale item G7 "psychomotor retardation." Comparing first and second assessments (paired samples t test) we found a statistically significant difference in UCB mean levels among SAF patients (p = .034).

CONCLUSIONS

There is potential in the research of UCB as a biological marker for SCZ and SAF spectrums disorders during relapse and partial remission of both syndromes.

A study in first-episode psychosis patients: does angiotensin I-converting enzyme (ACE) activity associated with genotype predict symptoms severity reductions after treatment with the atypical antipsychotic risperidone?

BACKGROUND

Our previous studies showed increased angiotensin I-converting enzyme (ACE) activity in chronic schizophrenia (SCZ) patients compared to healthy control (HC) volunteers, and the relevance of combining ACE genotype and activity for predicting SCZ was suggested.

METHODS

ACE activity was measured in plasma of ACE insertion/deletion (I/D) genotyped HC volunteers (N = 53) and antipsychotic-naïve first-episode psychosis (FEP) patients (N = 45), assessed at baseline (FEB-B) and also after 2-months (FEP-2M) of treatment with the atypical antipsychotic risperidone.

RESULTS

ACE activity measurements showed significant differences among HC, FEP-B and FEP-2M groups (F = 5.356, df = 2, p = 0.005), as well as between HC and FEP-2M (post-hoc Tukey's multiple comparisons test, p = 0.004). No correlation was observed for ACE activity increases and symptom severity reductions in FEP as assessed by total PANSS (r = -0.131, p = 0.434). FEP subgrouped by ACE I/D genotype showed significant ACE activity increases, mainly in the DD genotype subgroup. No correlation between ACE activity and age was observed in FEP or HC groups separately (r = 0.210, p = 0.392), but ACE activity levels differences observed between these groups were influenced by age.

CONCLUSIONS

The importance of measuring the ACE activity in blood plasma, associated to ACE I/D genotyping to support the follow-up of FEP patients did not show correlation with general symptoms amelioration in the present study. However, new insights into the influence of age and I/D genotype for ACE activity changes in FEP individuals upon treatment was demonstrated.

LINE-1 hypomethylation is associated with poor risperidone response in a first episode of psychosis cohort

Aim: We investigated the DNA methylation profile over LINE-1 in antipsychotic-naive, first-episode psychosis-patients (n = 69) before and after 2 months of risperidone treatment and in healthy controls (n = 62). Materials & methods: Patients were evaluated using standardized scales and classified as responders and nonresponders. DNA from blood was bisulfite converted and LINE-1 fragments were amplified and pyrosequencing was performed. Results: Lower LINE-1 methylation was observed in antipsychotic-naive first-episode psychosis patients than in healthy controls. Lower DNA methylation levels before treatment were associated with poor risperidone responses. A positive correlation was observed between LINE-1 methylation levels and positive symptoms response. Conclusion: Our study brings new insight regarding how epigenomic studies and clinical correlation studies can supplement psychosis treatment.

Negative symptom configuration in first episode Schizophrenia: findings from the "Parma Early Psychosis" program

Purpose: Identifying distinct dimensions of negative symptoms in First Episode Schizophrenia (FES) might result in a better understanding and treatment of this invalidating symptomatology. Aim of this study was to examine negative symptom structure in FES patients using the Positive and Negative Syndrome Scale (PANSS).Materials and Methods: All 147 participants, aged 12-35 years, completed the PANSS and the Global Assessment of Functioning (GAF) scale. A principal component analysis with varimax rotation was performed to investigate PANSS negative symptom structure in the FES total sample.Results: A 2-factor model (i.e. "Expressive Deficits" and "Asociality" dimensions) was identified. Only "Expressive Deficits" domain had a significant negative correlation with baseline GAF score.Conclusions: This bipartite solution seems to be adequate to describe the phenomenological variety of negative symptoms experienced by FES individuals at the point of entry in early intervention services.

Decreased Serum EGF in First-episode and Chronic Schizophrenia Patients: Negative Correlation with Psychopathology

Previous studies have demonstrated that neurotrophic factors may play a critical role in the severity of clinical symptoms in schizophrenia. However, it remains unknown whether serum levels of epidermal growth factor (EGF) in schizophrenia are similar to those observed in the case of other neurotrophic factors. Therefore, we compared serum EGF concentrations in first-episode drug-naive (FEP) patients and medicated chronic schizophrenic patients with healthy controls in order to explore whether EGF levels are related to psychopathological symptoms. We measured the serum levels of EGF in 78 first-episode medication-naive schizophrenia patients, 76 medicated chronic schizophrenic patients, and 75 healthy controls using the sandwich ELISA method. Disease severity were measured using the positive and negative syndrome scale (PANSS). Serum EGF levels showed a significant decrease in schizophrenia patients in comparison to healthy subjects. Serum EGF levels in FEP patients are indistinguishable from chronic cases. EGF levels were related to PANSS general symptom subscales in both FEP never-medicated and medicated patients. It is interesting that serum EGF levels were negatively correlated with the PANSS cognitive subscales, with the exception of the patients with chronic schizophrenia. Our preliminary results indicated that EGF may play a role in this illness and that it could be used as a potential biomarker of disease severity. Moreover, EGF may be associated with cognitive subscales of PANSS in FEP patients. Future studies should investigate the relationship between EGF and cognitive function as measured using standardized neuropsychological assessments to identify potential biomarkers related with cognition.

A symptom combination predicting treatment-resistant schizophrenia - A strategy for real-world clinical practice

Early identification of symptoms that can predict treatment-resistant schizophrenia (TRS) could help clinicians to avoid delays in clozapine therapy. This study aims to investigate symptom patterns that could predict TRS using a discovery/replication study design. First, we followed a cohort of inpatients with schizophrenia (n = 164) in which the most discriminative items at baseline of the Positive and Negative Syndrome Scale (PANSS) were determined using logistic regression with TRS status as an outcome. Using Receiver Operating Characteristic (ROC) curves, we tested the prediction performance of multiple combinations of the identified items. The same items' combination was tested in an independent replication sample of (n = 207) outpatients with schizophrenia. In the discovery sample, the best combination to predict TRS at the discharge was the sum of three baseline PANSS items - conceptual disorganization (P2), difficulty in abstract thinking (N5), and unusual thought content (G9). The P2 + N5 + G9 model yielded an area under the curve (AUC) of 0.881, a sensitivity of 77.8%, and a specificity of 83.3%. In the outpatient sample, the model P2 + N5 + G9 predictive accuracy for TRS was only in the range of "acceptable" with an AUC of 0.756 and sensitivity of 72.3% and a specificity of 74.4%. Overall, the P2 + N5 + G9 model corresponds to the construct of formal thought disorder composed of disorganized thinking, concrete thinking, and bizarre-idiosyncratic thinking. Pronounced levels of these symptoms are easily identifiable in clinical practice and may be a feasible strategy in TRS. Replicating in first-episode cohorts is desirable to understand the likely clinical utility.

Meta-analysis of the positive and Negative Syndrome Scale (PANSS) factor structure

A meta-analysis of the results of 45 factor analyses (n = 22,812) of the Positive and Negative Syndrome Scale (PANSS) was conducted. Meta-analyses of the PANSS was conducted using both a co-occurrence similarity matrix and reproduced correlations. Both methods produced similar results. Five factors (Positive Symptoms, Negative Symptoms, Disorganization, Affect and Resistance) emerged clearly across both analyses. The factors and the items defining them were Positive Symptoms (P1 Delusions, G9 Unusual thought content, P3 Hallucinatory behavior, P6 Suspiciousness and persecution, P5 Grandiosity), Negative Symptoms (N2 Emotional withdrawal, N1 Blunted affect, N4 Passive apathetic social withdrawal, N6 Lack of spontaneity, N3 Poor rapport, G7 Motor retardation, G16 Active social avoidance), Disorganization often termed Cognitive (P2 Conceptual disorganization, G11 Poor attention, N5 Difficulty in abstract thinking, G13 Disturbance of volition, N7 Stereotyped thinking, G5 Mannerisms/posturing, G15 Preoccupation, G10 Disorientation), Affect often termed Depression-Anxiety (G2 Anxiety, G6 Depression, G3 Guilt feelings, G4 Tension, G1 Somatic concern) and a small fifth factor that might be characterized as Resistance or Excitement/Activity (P7 Hostility, G14 Poor impulse control, P4 Excitement, G8 Uncooperativeness). Items G1, G4, G10, P5, G5, G15 may not be core items for the PANSS factors and G12 lack of judgment is not a core item. Results of the PANSS meta-analyses were relatively similar to those for meta-analysis of both the BPRS and BPRS-E all of which contain the original 18 BPRS items. The PANSS is distinguished by a much larger number of items to clearly define and measure Negative Symptoms as well as a sufficient number of items to much more clearly identify a Disorganization factor than the BPRS or BPRS-E.

Validation of the Brief Negative Symptom Scale and its association with functioning

INTRODUCTION

The Brief Negative Symptom Scale (BNSS) includes five domains of negative symptoms suggested by the NIMH Consensus Development Conference (anhedonia, asociality, avolition, blunted affect, and alogia), which could be clustered into two factors - Motivation-Pleasure (MAP) and Emotional Expressivity (EE). Our study aims to examine the psychometric properties of BNSS, and its association with functioning.

METHODS

274 individuals with schizophrenia were assessed on the BNSS, Positive and Negative Syndrome Scale (PANSS), Scale for the Assessment of Negative Symptoms (SANS), Global Assessment of Functioning Scale (GAF), Calgary Depression Scale for Schizophrenia (CDSS), and Simpson-Angus Extrapyramidal Side Effects Scale (SAS). Internal consistency was examined using Cronbach's alpha. Concurrent, discriminant, and construct validity were examined. Factor structure of BNSS was explored using confirmatory factor analyses. Association between GAF and BNSS was examined with GAF as the dependent variable and BNSS Total, MAP and EE, and BNSS five domains as independent variables in three multiple regression models after controlling for covariates.

RESULTS

BNSS showed good internal consistency (Cronbach's alpha = 0.880) and validity. The five-factor model fit the data better than the two-factor model; a second-order model was superior to both models. More severe symptoms on BNSS Total (B = -0.438, p < .001), MAP (B = -0.876, p < .001), Avolition (B = -2.503, p < .001) and Asociality (B = -0.950, p = .001) were associated with lower GAF.

CONCLUSION

Our results lend support to the use of BNSS in clinical practice and in future research into negative symptoms. Composite scores could be computed using either the five-factor or second-order models. Negative symptoms, particularly MAP, avolition and asociality, were associated with functioning.

Cognitive and Psychiatric Evaluation in SYNE1 Ataxia

SYNE1 gene mutations were identified as a cause of late-onset pure cerebellar syndrome. Non-cerebellar symptoms, including cognitive impairment, were already described in this condition. The aim of this study was to perform a detailed cognitive and psychiatric description of patients with SYNE1 gene mutations. We performed neuropsychological and psychiatric evaluations of six patients with SYNE1 ataxia and compared their performance with 18 normal controls paired for age and education level. SYNE1 ataxia patients present cognitive dysfunction, characterized by impairment in attention and processing speed domains. Otherwise, the psychiatric assessment reported low levels of overall behavioral symptoms with only some minor anxiety-related complaints. Although this is a small sample of patients, these results suggest that SYNE1 ataxia patients may represent a model to investigate effects of cerebellar degeneration in higher hierarchical cognitive functions. For further studies, abstract thinking impairment in schizophrenia may be related to dysfunction in cerebellum pathways.

A meta-analysis of transcranial direct current stimulation for schizophrenia: "Is more better?"

Transcranial direct current stimulation (tDCS) has generated interest in recent years as a potential adjunctive treatment for patients with schizophrenia. The primary objective of this meta-analysis was to evaluate the efficacy of tDCS on positive symptoms, particularly auditory hallucinations, and negative symptoms. A literature search of randomized sham-controlled trials was conducted using the OVID database on October 9, 2018. The standardized mean differences (SMDs) were calculated to examine changes in symptom severity between active and sham groups for the following symptom domains: auditory hallucinations, positive symptoms (including auditory hallucinations), and negative symptoms. Moderator analyses were performed to examine the effects of study design and participant demographics. We identified 10 eligible studies. Main-analyses showed no effects of tDCS on auditory hallucinations (7 studies, n = 242), positive symptoms (9 studies, n = 313), or negative symptoms (9 studies, n = 313). Subgroup analyses of studies that applied twice-daily stimulation showed a significant reduction in the severity of auditory hallucinations (4 studies, n = 138, SMD = 1.04, p = 0.02). Studies that applied ≥10 stimulation sessions showed a reduction in both auditory hallucination (5 studies, n = 186, SMD = 0.86, p = 0.009) and negative symptom severity (7 studies, n = 257, SMD = 0.41, p = 0.04). Meta-regression analyses revealed a negative association between mean age and the SMDs for auditory hallucinations and negative symptoms, and a positive association between baseline negative symptom severity and the SMDs for negative symptoms. Our findings highlight the need to optimize tDCS parameters and suggest twice-daily or 10 or more stimulation sessions may be needed to improve clinical outcomes in patients with schizophrenia.

Cannabis acute use impacts symptoms and functionality in a cohort of antipsychotic naïve First Episode of Psychosis individuals

Introduction

Cannabis use increases the risk of developing psychosis, and subjects with psychosis are more likely to use cannabis. However, studies on the influence of cannabis on psychotic dimensions, response to treatment, and functional outcomes showed conflicting results. Such heterogeneity may be due the inclusion of patients who were already under treatment, and lack of specificity in evaluations. We investigated whether cannabis use yields distinct symptom profiles and functionality in a cohort of antipsychotic-naïve patients at first episode of psychosis (FEP).

Methods

This research is part of a prospective cohort study performed in Sao Paulo, Brazil. The baseline assessment was completed by 175 individuals, and 99 of them were reassessed in a ten-week follow up. We investigated the relationship between cannabis exposure variables (acute use, lifetime use and age at first use) and outcomes: symptom dimensions and functioning.

Results

Individuals who reported acute use of cannabis had higher excitement symptoms at baseline, higher excitement and positive response rates, but no significant differences at follow-up. Additionally, more days of cannabis use in the last month predicted worse functionality and clinical impression at baseline but not at follow-up.

Discussion

The acute use of cannabis influenced the clinical presentation at our FEP baseline assessment, but did not to influence symptoms or functional outcomes at 10-week follow-up. Additionally, acute cannabis users had a better response for excitement and positive symptoms. Higher excitement symptoms at presentation of FEP should raise concerns of possible acute use of cannabis. Longer follow-up times may elucidate whether the effects on functionality would be more evident later in disease development.

Component mechanisms of executive function in schizophrenia and their contribution to functional outcomes

OBJECTIVE

In schizophrenia, scores reflecting deficits in different cognitive processes are strongly correlated, making it difficult to establish a solid relationship between different cognitive mechanisms and other features of this disorder. The objective of this study was to explore whether three frequently postulated executive functions (updating, shifting, and inhibition) could be compared between groups and considered independently in terms of their respective roles in functional outcome.

METHODS

This study relied on confirmatory factor analysis of schizophrenia patients (n=141) and healthy controls (n=119). The main analyses examined the degree to which three executive functions (updating, set-shifting, and inhibition) could be separated in schizophrenia and compared this model among groups. Structural equation modeling analysis was also performed to examine the extent to which executive function components contribute to functional outcome in schizophrenia.

RESULTS

Multiple-group confirmatory factor analysis with unconstrained model parameters indicated that the full three-factor model may fit the data in both groups (χ2 = 61.48, degrees of freedom = 34, p < 0.001, comparative fit index = 0.95; standardized root mean square residual = 0.037; root mean square error of approximation = 0.04; Akaike's information criteria = 169.49; normed fit index = 0.90), although there was also a good data fit for the patient group with a two-factor model. In the patient group, structural equation modeling suggested that shifting and (principally) updating were associated with the general measure of functional outcome (regression path coefficients: 0.34, p < 0.005; 0.39, p < 0.005, respectively), although when combined the mechanisms fail to contribute.

CONCLUSION

This data suggests that the factor structure may be similar but not identical between groups, and both updating and shifting may play an important role in functional outcome in schizophrenia.

Polygenic risk score analyses of symptoms and treatment response in an antipsychotic-naive first episode of psychosis cohort

In this study, we aimed to test if the schizophrenia (SCZ) polygenic risk score (PRS) was associated with clinical symptoms in (a) the first episode of psychosis pre-treatment (FEP), (b) at nine weeks after initiation of risperidone treatment (FEP-9W) and (c) with the response to risperidone. We performed a detailed clinical assessment of 60 FEP patients who were antipsychotic-naive and, again, after nine weeks of standardized treatment with risperidone. After blood collection and DNA isolation, the samples were genotyped using the Illumina PsychArrayChip and then imputed. To calculate PRS, we used the latest available GWAS summary statistics from the Psychiatric Genomics Consortium wave-2 SCZ group as a training set. We used Poisson regression to test association between PRS and clinical measurements correcting for the four principal components (genotyping). We considered a p-value < 0.0014 (Bonferroni correction) as significant. First, we verified that the schizophrenia PRS was also able to distinguish cases from controls in this south-eastern Brazilian sample, with a similar variance explained to that seen in Northern European populations. In addition, within-cases analyses, we found that PRS is significantly correlated with baseline (pre-treatment) symptoms, as measured by lower clinical global assessment of functioning (-GAF), higher depressive symptoms and higher scores on a derived excitement factor. After standardized treatment for nine weeks, the correlation with GAF and the excitement factor disappeared while depressive symptoms became negatively associated with PRS. We conclude that drug (and other treatments) may confound attempts to understand the aetiological influence on symptomatology of polygenic risk scores. These results highlight the importance of studying schizophrenia, and other disorders, pre-treatment to understand the relationship between polygenic risk and phenotypic features.

Need for information in a representative sample of outpatients with schizophrenia disorders

BACKGROUND

Providing adequate information and involving patients in treatment have become an essential component of mental health care. Despite this, research regarding the extent to which this need has been met in clinical services is still scarce.

AIMS

To investigate the need for information about psychiatric condition and treatment among outpatients with schizophrenia disorders and how this need is associated with service use, adjusting for sociodemographic and clinical characteristics.

METHODS

Need for information about condition and treatment, using the corresponding domain in the Camberwell Assessment of Need (CAN), in a representative sample of 401 schizophrenia outpatients in Santos, Brazil was assessed. Hierarchical logistic regression was used to investigate the association of information as a reported need and as an unmet need with service use variables, adjusting for sociodemographic and clinical characteristics.

RESULTS

Need for information was reported by 214 (53.4%) patients, being met in 101 (25.2%) and unmet in 113 (28.2%). Hierarchical regression indicated a significant association of a reported need with higher age of onset, family monitoring medication use last year and lower education level, which was only associated with an unmet need.

CONCLUSION

Information was a commonly reported need and which was often unmet, showing no significant association with service use. Greater attention should be given by mental health services to information provision.

The Brief Negative Symptom Scale: Validation in a multicenter Brazilian study

BACKGROUND

Negative symptoms are a core feature of schizophrenia. The Brief Negative Symptom Scale (BNSS) is a scale developed to measure negative symptoms in schizophrenia.

METHODS

The present study aimed to examine the construct validity of BNSS, by using convergent and divergent validities as well as factor analysis, in a Brazilian sample of 111 outpatients diagnosed with schizophrenia by DSM-5. Patients were evaluated by the Brazilian version of the BNSS and positive and negative subscales of the Positive and Negative Syndrome Scale (PANSS).

RESULTS

Assessment of patients by both instruments revealed an excellent internal consistency (Cronbach's alpha = 0.938) or inter-rater reliability (ICC = 0.92), as well as a strong correlation between BNSS and Marder negative PANSS (r = 0.866) and a weak correlation of the instrument with the positive PANSS (r = 0.292), thus characterizing convergent and discriminant validities, respectively. The exploratory factor analysis identified two distinct factors, namely, motivation/pleasure and emotional expressivity, accounting for 68.63% of the total variance.

CONCLUSION

The study shows that the Brazilian version of the BNSS has adequate psychometric properties and is a reliable instrument for the assessment of negative symptoms in schizophrenia, either for clinical practice or research.

Effects of transcranial direct current stimulation on working memory and negative symptoms in schizophrenia: a phase II randomized sham-controlled trial

BACKGROUND

The lack of efficacy of pharmacological treatments for cognitive and negative symptoms in schizophrenia highlights the need for new interventions. We investigated the effects of tDCS on working memory and negative symptoms in patients with schizophrenia.

METHOD

Double-blinded, randomized, sham-controlled clinical trial, investigating the effects of 10 sessions of tDCS in schizophrenia subjects. Stimulation used 2 mA, for 20 min, with electrodes of 25 cm2 wrapped in cotton material soaked in saline solution. Anode was positioned over the left DLPFC and the cathode in the contralateral area. Twenty-four participants were assessed at baseline, after intervention and in a three-months follow-up. The primary outcome was the working memory score from MATRICS and the secondary outcome the negative score from PANSS. Data were analyzed using generalized estimating equations.

RESULTS

We did not find group ∗ time interaction for the working memory (p = 0.720) score or any other cognitive variable (p > 0.05). We found a significant group ∗ time interaction for PANSS negative (p < 0.001, d = 0.23, CI.95 = -0.59-1.02), general (p = 0.011) and total scores (p < 0.001). Exploratory analysis of PANSS 5 factors suggests tDCS effect on PANSS negative (p = 0.012), cognitive (p = 0.016) and depression factors (p = 0.029).

CONCLUSION

The results from this trial highlight the therapeutic effects of tDCS for treatment of persistent symptoms in schizophrenia, with reduction of negative symptoms. We were not able to confirm the superiority of active tDCS over sham to improve working memory performance. Larger sample size studies are needed to confirm these findings.

Hemoencephalography self-regulation training and its impact on cognition: A study with schizophrenia and healthy participants

BACKGROUND

Cognitive impairments in schizophrenia are strongly correlated to functional outcome and recovery rates, with no pharmacological agent approved for its treatment. Neurofeedback has emerged as a non-pharmacological approach to enhance neuroplasticity, which consists in inducing voluntary control of brain responses through operant conditioning.

METHOD

The effects of hemoencephalography neurofeedback (HEG-NFBK) in 4 brain sites (F7, Fp1, Fp2 and F8) was studied in 8 patients with schizophrenia (SCH, mean age 36.5±9.98) and 12 health controls (mean age 32.17±5.6). We analyzed groups' performance (10 sessions) and cognitive differences in 3 time points (baseline, after training and follow-up) with generalized estimated equations. For SCH we also evaluate the impact on psychopathology.

RESULTS

We found a group∗time interaction for HEG-NFBK performance in the left hemisphere sites (F7 an Fp1) and a near-to-significant in the right frontotemporal region (F8), with no group differences and a significant time effect. Most of cognitive domains improved after intervention, including information processing speed, attention processing, working memory, executive functioning, verbal and visual learning. No group∗time interaction was found. Results suggest that both groups benefit from HEG-NFBK training regardless of cognitive differences at baseline. No significant time effects were found for Calgary and PANSS total scale and subscales (positive, negative neither general).

CONCLUSION

To our knowledge, this is the first controlled trial showing effects of NFBK on cognitive performance improvement in schizophrenia. Further research investigating the effects of HEG-NFBK training in schizophrenia should be performed.

Metabolomics and lipidomics analyses by 1H nuclear magnetic resonance of schizophrenia patient serum reveal potential peripheral biomarkers for diagnosis

Using ¹H NMR-based metabolomics in association to chemometrics analysis, we analyzed here the metabolic differences between schizophrenia patients (SCZ) compared to healthy controls (HCs). HCs and SCZ patients underwent clinical interview using the Structured Clinical Interview for DSM Disorders (SCID). SCZ patients were further assessed by Positive and Negative Syndrome Scale (PANSS), Calgary Depression Scale, Global Assessment of Functioning Scale (GAF), and Clinical Global Impressions Scale (CGI). Using the principal component analysis (PCA) and supervised partial least-squares discriminate analysis (PLS-DA) in obtained NMR data, a clear group separation between HCs and SCZ patients was achieved. Interestingly, all metabolite compounds identified as exclusively present in the SCZ group, except for the gamma-aminobutyric acid (GABA), were never previously associated with mental disorders. Although the initial perception of an absence of obvious biological link among the different key molecules exclusively observed in each group, and no identification of any specific pathway yet, the present work represents an important contribution for the identification of potential biomarkers to inform diagnosis, as it was possible to completely separate the affected SCZ patients from HCs, with no outliers or exceptions. In addition, the data presented here reinforced the role of the modulation of glycolysis pathway and the loss of GABA interneuron/hyperglutamate hypothesis in SCZ.

Psychosis in Machado-Joseph Disease: Clinical Correlates, Pathophysiological Discussion, and Functional Brain Imaging. Expanding the Cerebellar Cognitive Affective Syndrome

Machado-Joseph disease (MJD) is the most common spinocerebellar ataxia worldwide with a broad range of clinical manifestations, but psychotic symptoms were not previously characterized. We investigated the psychiatric manifestations of a large cohort of Brazilian patients with MJD in an attempt to characterize the presence of psychotic symptoms. We evaluated 112 patients with clinical and molecular diagnosis of MJD from February 2008 to November 2013. Patients with psychotic symptoms were referred to psychiatric evaluation and brain perfusion single-photon emission computed tomography (SPECT) analysis. A specific scale-Positive and Negative Syndrome Scale (PANSS)-was used to characterize psychotic symptoms in MJD patients. We also performed an autopsy from one of the patients with MJD and psychotic symptoms. Five patients presented psychotic symptoms. Patients with psychotic symptoms were older and had a late onset of the disease (p < 0.05). SPECT results showed that MJD patients had significant regional cerebral blood flow (rCBF) decrease in the cerebellum bilaterally and vermis compared with healthy subjects. No significant rCBF differences were found in patients without psychotic symptoms compared to patients with psychotic symptoms. The pathological description of a patient with MJD and psychotic symptoms revealed severe loss of neuron bodies in the dentate nucleus and substantia nigra. MJD patients with a late onset of the disease and older ones are at risk to develop psychotic symptoms during the disease progression. These clinical findings may be markers for an underlying cortical-cerebellar disconnection or degeneration of specific cortical and subcortical regions that may characterize the cerebellar cognitive affective syndrome.

New evidence in support of staging approaches in schizophrenia: Differences in clinical profiles between first episode, early stage, and late stage

Few studies have examined the progression of symptom dimensions in schizophrenia patients over the course of the illness. The objective of this study was to investigate whether clinical and psychopathological differences exist between first-episode schizophrenia (FES) and multiple-episode patients in an inpatient setting. Patients (N=203) were evaluated using the Positive and Negative Syndrome Scale (PANSS) over time. Five different generalized estimating equations were built for the PANSS factors using the following as covariates: sex, patient's age, assessment time point (i.e., moment of patient's evaluation, with a minimum of two and a maximum of four assessments throughout the study timeframe). The FES group was used as the reference to which the groups with up to five years of illness and more than five years of illness were compared. Remission rates and treatment resistance (TRS) rates were also compared. Generalized estimating equations were used to allow for different numbers of assessments over the study period. Patients with FES showed significantly milder severity in positive, disorganized, and hostility factors. Also, FES patients were more likely to achieve remission (P=0.002) and had lower rates of TRS (P=0.001). First-episode schizophrenia seems to be the critical period to improve outcome, as multiple-episode patients were similar in clinical characteristics regardless of illness duration.

Gene expression alterations related to mania and psychosis in peripheral blood of patients with a first episode of psychosis

Psychotic disorders affect ~3% of the general population and are among the most severe forms of mental diseases. In early stages of psychosis, clinical aspects may be difficult to distinguish from one another. Undifferentiated psychopathology at the first-episode of psychosis (FEP) highlights the need for biomarkers that can improve and refine differential diagnosis. We investigated gene expression differences between patients with FEP-schizophrenia spectrum (SCZ; N=53) or FEP-Mania (BD; N=16) and healthy controls (N=73). We also verified whether gene expression was correlated to severity of psychotic, manic, depressive symptoms and/or functional impairment. All participants were antipsychotic-naive. After the psychiatric interview, blood samples were collected and the expression of 12 psychotic-disorder-related genes was evaluated by quantitative PCR. AKT1 and DICER1 expression levels were higher in BD patients compared with that in SCZ patients and healthy controls, suggesting that expression of these genes is associated more specifically to manic features. Furthermore, MBP and NDEL1 expression levels were higher in SCZ and BD patients than in healthy controls, indicating that these genes are psychosis related (independent of diagnosis). No correlation was found between gene expression and severity of symptoms or functional impairment. Our findings suggest that genes related to neurodevelopment are altered in psychotic disorders, and some might support the differential diagnosis between schizophrenia and bipolar disorder, with a potential impact on the treatment of these disorders.

Increased expression of NDEL1 and MBP genes in the peripheral blood of antipsychotic-naïve patients with first-episode psychosis

Schizophrenia is a multifactorial neurodevelopmental disorder with high heritability. First-episode psychosis (FEP) is a critical period for determining the disease prognosis and is especially helpful for identifying potential biomarkers associated with the onset and progression of the disorder. We investigated the mRNA expression of 12 schizophrenia-related genes in the blood of antipsychotic-naïve FEP patients (N=73) and healthy controls (N=73). To evaluate the influences of antipsychotic treatment and progression of the disorder, we compared the gene expression within patients before and after two months of treatment with risperidone (N=64). We observed a significantly increased myelin basic protein (MBP) and nuclear distribution protein nudE-like 1 (NDEL1) mRNA levels in FEP patients compared with controls. Comparing FEP before and after risperidone treatment, no significant differences were identified; however; a trend of relatively low NDEL1 expression was observed after risperidone treatment. Animals chronically treated with saline or risperidone exhibited no significant change in Ndel1 expression levels in the blood or the prefrontal cortex (PFC), suggesting that the trend of low NDEL1 expression observed in FEP patients after treatment is likely due to factors other than risperidone treatment (i.e., disease progression). In addition to the recognized association with schizophrenia, MBP and NDEL1 gene products also play an essential role in the functions that are deregulated in schizophrenia, such as neurodevelopment. Our data strengthen the importance of these biological processes in psychotic disorders, indicating that these changes can be detected peripherally and potentially represent putative novel blood biomarkers of susceptibility and disorder progression.

Angiotensin converting enzyme activity is positively associated with IL-17a levels in patients with schizophrenia

Previous studies of our group showed increased plasmatic Angiotensin-I Converting Enzyme (ACE) activity in schizophrenia (SCZ) patients compared to healthy controls, which was also associated to poor cognitive functioning. The ACE main product angiotensin II (Ang-II) has pro-inflammatory properties. Activated immune-inflammatory responses in SCZ and their association with disease progression and cognitive impairments are also well-described. Therefore, we examined here the association of plasma ACE activity and inflammatory mediators in 33 SCZ patients and 92 healthy controls. Non-parametric correlations were used to investigate the association of the enzyme activity and the peripheral levels of immune inflammatory markers as interleukins, tumor necrosis factor (TNF-α), and interferon (IFN-γ). Although no significant correlations could be observed for ACE activity and measured cytokines levels in healthy controls, a significant positive correlation for ACE enzymatic activity and IL-17a levels was observed in SCZ patients. Correcting for gender did not change these results. Moreover, a significant association for ACE activity and IFN-γ levels was also observed. To our knowledge, this is the first study to show a significant association between higher ACE activity and the levels of cytokines, namely IL-17a and IFN-γ, in patients with SCZ.

ACE I/D genotype-related increase in ACE plasma activity is a better predictor for schizophrenia diagnosis than the genotype alone

BACKGROUND

Angiotensin-I converting enzyme (ACE) is a key component of the renin-angiotensin system (RAS). Although the several contradictory data, ACE has been associated with schizophrenia (SCZ) pathophysiology. Here the ACE activity of SCZ patients and healthy controls (HCs), and its possible correlations with the ACE polymorphism genotype and symptomatic dimensions, was investigated.

METHODOLOGY

ACE activity of 86 SCZ patients and 100 HCs paired by age, gender and educational level was measured, using the FRET peptide substrate and the specific inhibitor lisinopril. The ACE insertion/deletion (I/D) genotypes were assessed by the restriction fragment length polymorphism (RFLP) technique.

RESULTS

Significantly higher ACE activity was observed in SCZ patients compared to HCs (t=-5.09; p<0.001). The area under the receiver operating characteristic (ROC) curve was 0.701. Mean ACE activity levels were higher for the D-allele carriers (F=5.570; p=0.005), but no significant difference was found among SCZ patients and HCs for genotypes frequencies (Chi-squared=2.08; df=2; p=0.35). Interestingly, we found that the difference between the measured ACE activity for each SCZ patient and the expected average mean value for each respective genotype group (for control subjects) was a better predictor of SCZ than the ACE dichotomized values (high/low) or ACE I/D.

CONCLUSION

Our results suggest that higher levels of ACE activity are associated with SCZ with stronger impact when the genetic background of each individual is considered. This may explain the heterogeneity of the results on ACE previously reported.