Cognitive Profile in Ultra High Risk for Psychosis and Schizophrenia: A Comparison Using Coordinated Norms

Abnormalities in cognitive-related functional connectivity can be used to identify patients with schizophrenia and individuals in clinical high-risk

BACKGROUND

Clinical high-risk (CHR) refers to prodromal phase before schizophrenia onset, characterized by attenuated psychotic symptoms and functional decline. They exhibit similar but milder cognitive impairments, brain abnormalities and eye movement change compared with first-episode schizophrenia (FSZ). These alterations may increase vulnerability to transitioning to the disease. This study explores cognitive-related functional connectivity (FC) and eye movement abnormalities to examine differences in the progression of schizophrenia.

METHODS

Thirty drug-naive FSZ, 28 CHR, and 30 healthy controls (HCs) were recruited to undergo resting-state functional magnetic resonance imaging (rs-fMRI). Connectome-based predictive modeling (CPM) was employed to extract cognitive-related brain regions, which were then selected as seeds to form FC networks. Support vector machine (SVM) was used to distinguish FSZ from CHR. Smooth pursuit eye-tracking tasks were conducted to assess eye movement features.

RESULTS

FSZ displayed decreased cognitive-related FC between right posterior cingulate cortex and right superior frontal gyrus compared with HCs and between right amygdala and left inferior parietal gyrus (IPG) compared with CHR. SVM analysis indicated a combination of BACS-SC and CFT-A scores, and FC between right amygdala and left IPG could serve as a potential biomarker for distinguishing FSZ from CHR with high sensitivity. FSZ also exhibited a wide range of eye movement abnormalities compared with HCs, which were associated with alterations in cognitive-related FC.

CONCLUSIONS

FSZ and CHR exhibited different patterns of cognitive-related FC and eye movement alteration. Our findings illustrate potential neuroimaging and cognitive markers for early identification of psychosis that could help in the intervention of schizophrenia in high-risk groups.

Psychometric properties of the Spanish version of the measure of insight into cognition-self-report in psychosis-risk and non-clinical Mexican young adults

AIM

Cognitive disturbances typically precede the onset of overt psychotic symptoms and represent a neurobiological marker for psychosis risk that is also associated with poor functional outcomes. The Measure of Insight into Cognition-Self Report (MIC-SR) is a widely used 12-item questionnaire that assesses the perceived frequency of cognitive impairment in the domains of executing functioning, attention, and memory. However, the MIC-SR is not available in Spanish, one of the most widely spoken languages worldwide. The present study aimed to provide a Spanish version of the MIC-SR and examine its psychometric properties in psychosis-risk and non-clinical Mexican young adults.

METHODS

The sample comprised 621 participants who completed a battery of self-report measures via an online survey. Of the participants, 478 were non-clinical, and 143 met the screening criteria for a clinical high-risk for psychosis (CHR-positive).

RESULTS

Confirmatory Factor Analyses supported a one-factor model, consistent with the findings for the original MIC-SR. The results showed adequate fit indices for the general model and the independent models for both groups, with high Cronbach's alpha coefficients. Furthermore, the CHR-positive group showed more frequent subjective cognitive problems on each of the 12 items, higher total scores, and higher average frequency than the non-clinical group.

CONCLUSION

To our knowledge, this is the first translation of the MIC-SR into Spanish. Using the MIC-SR at the CHR stage may contribute to our understanding of cognitive processes associated with the onset of a psychotic disorder and provide valuable information in the context of detection and early intervention efforts.

Montreal Cognitive Assessment (MoCA) as a screening tool for cognitive impairment in early stages of psychosis

Background

Cognitive alterations have been reported in early stages of psychosis including people with First Episode Psychosis (FEP), Clinical High-Risk Mental State (CHR), and Psychotic-Like Experience (PLE). This study aimed to compare the cognitive function in early stages of psychosis using the Montreal Cognitive Assessment (MoCA), a low-cost and brief assessment tool of cognitive functions.

Methods

A total of 154 individuals, including 35 with FEP, 38 CHR, 44 PLE, and 37 healthy controls (HC), were evaluated with the MoCA in Santiago, Chile. We calculated the mean total score of the MoCA and the standard deviation of the mean. Groups were assessed for a trend to lower scores in a pre-determined sequence (HC > PLE > CHR > FEP) using the Jonckheere-Terpstra test (TJT).

Results

The mean total MoCA scores were 24.8 ± 3.3 in FEP, 26.4 ± 2.4 in CHR, 26.4 ± 2.3 in PLE, and 27.2 ± 1.8 in HC. The analyses revealed a significant trend (p < 0.05) toward lower MoCA individual domain scores and MoCA total scores in the following order: HC > PLE > CHR > FEP. The mean total scores of all groups were above the cut-off for cognitive impairment (22 points).

Conclusions

The MoCA describes lower scores in cognition across early stages of psychosis and may be a useful low-cost assessment instrument in early intervention centers of poorly resourced settings.

The Comparison of Lifestyles, Mental Risks, and Physical Indices among Individuals with Ultra-High Risk of Psychosis, Patients with Schizophrenia, and the General Public

(1) Background: Early interventions may effectively reduce the risk of mental disorders in individuals with ultra-high risk. Specifying the health needs of individuals with ultra-high risk is crucial before the implementation of successful early intervention. This study aimed to explore the differences in lifestyles, mental risks, and physical indices among individuals with ultra-high risk, patients with schizophrenia, and healthy subjects. (2) Methods: A cross-section design applying seven questionnaires with physical examinations for 144 participants aged 13-45 years old was conducted in this study. The questionnaires included one about personal data, four on mental risks, and two for lifestyles. (3) Results: The individuals with ultra-high risk scored similarly in many dimensions as the patients with schizophrenia, but they displayed lower positive symptoms, lower negative symptoms, lower prodromal symptoms, higher interpersonal deficits, lower nutrition intake, and higher levels of exercise than the patients with schizophrenia. Female individuals with ultra-high risk had lower self-esteem, higher positive symptoms, lower nutrition intake, and higher exercise levels than male ones. (4) Conclusions: The study pinpointed specific health needs with interpersonal deficits, nutrition intake, and physical activity for the individuals with ultra-high risk. Future interventions targeted on improving social function, dietary pattern, and exercise will be beneficial.

Unveiling the potential of machine learning in schizophrenia diagnosis: A meta-analytic study of task-based neuroimaging data

The emergence of machine learning (ML) techniques has opened up new avenues for identifying biomarkers associated with schizophrenia (SCZ) using task-related fMRI (t-fMRI) designs. To evaluate the effectiveness of this approach, we conducted a comprehensive meta-analysis of 31 t-fMRI studies using a bivariate model. Our findings revealed a high overall sensitivity of 0.83 and specificity of 0.82 for t-fMRI studies. Notably, neuropsychological domains modulated the classification performance, with selective attention demonstrating a significantly higher specificity than working memory (β = 0.98, z = 2.11, P = 0.04). Studies involving older, chronic patients with SCZ reported higher sensitivity (P <0.015) and specificity (P <0.001) than those involving younger, first-episode patients or high-risk individuals for psychosis. Additionally, we found that the severity of negative symptoms was positively associated with the specificity of the classification model (β = 7.19, z = 2.20, P = 0.03). Taken together, these results support the potential of using task-based fMRI data in combination with machine learning techniques to identify biomarkers related to symptom outcomes in SCZ, providing a promising avenue for improving diagnostic accuracy and treatment efficacy. Future attempts to deploy ML classification should consider the factors of algorithm choice, data quality and quantity, as well as issues related to generalization.

Investigation of Neurocognitive Deficits, Quality of Life, and Functional Performance in Ultra-High-Risk Individuals Compared to Familial High-Risk Individuals for Schizophrenia

Objective: This study aimed to investigate neurocognitive functioning, quality of life, and global functional performance in Ultra-High Risk (UHR) individuals compared to Familial High-Risk (FHR) individuals for developing schizophrenia. Method : An observational cross-sectional study was conducted using a convenient sampling method at Roozbeh Hospital in Tehran, Iran, from June 2017 to January 2020. The study included 40 UHR individuals based on the Structured Interview for Psychosis Syndrome (SIPS) interview, as well as 34 FHR individuals due to genetic risk. Neurocognitive functioning, quality of life, and global functional performance were assessed by using the Cambridge Automated Neuropsychological Test Battery (CANTAB) and Controlled Oral Word Association Test (COWAT), Quality of Life Scale (QLS), and Global Assessment of Functioning (GAF). Results: UHR individuals for schizophrenia demonstrated significant lower scores in phonemic and semantic verbal fluency (t = 6.218, P < 0.001; t = 4.184, P < 0.001, respectively), more total errors for spatial working memory (t = -5.874, P < 0.001), and fewer problems solved in minimum moves in Stocking of Cambridge (SOC) (t = -2.706, P < 0.01) compared to FHR individuals. Intra-Extra Dimension (IED) did not differ significantly between the two groups. Moreover, the study indicated significant GAF decline (F = 79.257, P < 0.001) and lower total score on the QLS (t = -10.655, P < 0.001) in UHR compared to FHR individuals. Conclusion: It is possible to differentiate UHR individuals from FHR individuals through neurocognitive, quality of life, and global functioning assessment.

Patterns of Impaired Neurocognitive Performance on the Global Neuropsychological Assessment, and Their Brain Structural Correlates in Recent-onset and Chronic Schizophrenia

Objective

Schizophrenia is associated with impairment in multiple cognitive domains. There is a paucity of research on the effect of prolonged illness duration (≥ 15 years) on cognitive performance along multiple domains. In this pilot study, we used the Global Neuropsychological Assessment (GNA), a brief cognitive battery, to explore the patterns of cognitive impairment in recent-onset (≤ 2 years) compared to chronic schizophrenia (≥ 15 years), and correlate cognitive performance with brain morphometry in patients and healthy adults.

Methods

We assessed cognitive performance in patients with recent-onset (n = 17, illness duration ≤ 2 years) and chronic schizophrenia (n = 14, duration ≥ 15 years), and healthy adults (n = 16) using the GNA and examined correlations between cognitive scores and gray matter volumes computed from T1-weighted magnetic resonance imaging images.

Results

We observed cognitive deficits affecting multiple domains in the schizophrenia samples. Selectively greater impairment of perceptual comparison speed was found in adults with chronic schizophrenia (p = 0.009, η2partial = 0.25). In the full sample (n = 47), perceptual comparison speed correlated significantly with gray matter volumes in the anterior and medial temporal lobes (TFCE, FWE p < 0.01).

Conclusion

Along with generalized deficit across multiple cognitive domains, selectively greater impairment of perceptual comparison speed appears to characterize chronic schizophrenia. This pattern might indicate an accelerated or premature cognitive aging. Anterior-medial temporal gray matter volumes especially of the left hemisphere might underlie the impairment noted in this domain in schizophrenia.

Associations between saliva alpha-amylase, heart rate variability, saliva cortisol and cognitive performance in individuals at ultra high-risk for psychosis

BACKGROUND

Cognitive impairments are present in individuals at ultra-high risk (UHR) of psychosis and UHR individuals exhibit a hyperactive and dysfunctional HPA-axis. Increasing stress levels could potentially lead to cognitive impairments and no previous studies have examined the association between physiological stress biomarkers and cognition in UHR individuals. This study aims to examine the association between saliva alpha amylase (SAA), heart rate variability (HRV), saliva cortisol, and cognition in UHR individuals.

METHOD

We included 72 UHR individuals, aged 18-40, fulfilling criteria of the comprehensive assessment of at-risk mental state (CAARMS). Cognitive tests indexed the 7 core domains as stated by Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS). Physiological stress levels were observed for one day: saliva was collected at awakening, 30 min and 60 min after awakening and at bedtime. HRV was measured during sleep and before awakening. We used generalized linear model and controlled for multiple testing using false discovery rate (FDR).

RESULTS

Higher levels of SAA were significantly associated with lower cognitive performance in the domains of verbal and visual learning and memory, sustained attention, working memory and global neurocognition looking at unadjusted data. Controlling for FDR visual memory, sustained attention and global neurocognition remained significant associated with SAA. We discovered no associations between cortisol and cognition.

CONCLUSION

Visual learning and memory, sustained attention and global neurocognition remained significantly associated with SAA. This finding supports our hypothesis that an association between abnormal stress biomarkers and impaired cognition might be present in UHR individuals.

The role of semantic clustering in the relationship between verbal memory and psychosocial functioning in schizophrenia and bipolar disorder: Possible distinct cognitive pathway compared to healthy controls

BACKGROUND

Verbal memory (VM) is impaired in schizophrenia (SZ) and bipolar disorder (BD), and predicts psychosocial functioning. However, there is a lack of research exploring the role of VM component processes, including semantic clustering, in these disorders. Semantic clustering might impact this association, as effective semantic memory strategies may reflect unimpaired executive control, leading to an adequate functioning. We aimed to investigate VM components in SZ and BD, and the role of semantic clustering in the relationship between VM and functioning.

METHODS

We included 495 participants (156 SZ, 172 BD, and 167 healthy controls (HC)) that underwent an assessment using the Hopkins Verbal Learning Test - Revised for VM and the Functioning Assessment Short Test for psychosocial functioning. We compared groups through ANOVAs and investigated the effect of semantic clustering in the relationship between VM total immediate free recall and functioning through linear regression models.

RESULTS

SZ had worse overall VM performance compared to BD, which performed worse than HCs. HCs used more semantic clustering than SZ and BD, but there were no differences between the two clinical groups. In HCs, semantic clustering impacted the relationship between VM performance and functioning, while no interaction was observed in SZ or BD.

LIMITATIONS

Cross-sectional design; no medication effects or other cognitive functions were assessed.

CONCLUSIONS

SZ and BD may use an alternative cognitive pathway in which the relationship between VM and functioning is independent of complex cognitive processes such as semantic clustering, supporting the cognitive remediation targeting of VM in these disorders.

Associations between symptom and neurocognitive dimensions in clinical high risk for psychosis

Introduction

Clinical high risk for psychosis (CHR) is associated with mild cognitive impairments. Symptoms are clustered into positive, negative and disorganization symptoms. The association between specific symptom dimensions and cognitive functions remains unclear. The aim of this study was to investigate the associations between cognitive functions and positive, negative, and disorganization symptoms.

Method

53 CHR subjects fulfilling criteria for attenuated psychotic syndrome in the Structural Interview for Prodromal Syndromes (SIPS) were assessed for cognitive function. Five cognitive domain z-scores were defined by contrasting with observed scores of a group of healthy controls (n = 40). Principal Components Analyses were performed to construct general cognitive composite scores; one using all subtests and one using the cognitive domains. Associations between cognitive functions and symptoms are presented as Spearman's rank correlations and partial Spearman's rank correlations adjusted for age and gender.

Results

Positive symptoms were negatively associated with executive functions and verbal memory, and disorganization symptoms with poorer verbal fluency. Negative symptoms were associated with better executive functioning. There were no significant associations between the general cognitive composites and any of the symptom domains, except for a trend for positive symptoms.

Conclusion

In line with previous research, data indicated associations between positive symptoms and poorer executive functioning. Negative symptoms may not be related to executive functions in CHR the same way as in psychosis. Our results could indicate that attenuated positive symptoms are more related to cognitive deficits in CHR than positive symptoms in schizophrenia and FEP.

Cognitive Patterns and Conversion in a Representative Sample of Individuals at Risk for Psychosis

ABSTRACT

Clinical high-risk (CHR) individuals belong to a heterogeneous group, of which only a few will cross the threshold for a clinical diagnosis. Cognitive disturbances are present in CHR subjects and may be indicative of transition. Our study aims to identify such deficits in a representative CHR for psychosis sample. Our sample comprised 92 CHR individuals and 54 controls from a representative cohort of the general population. They were followed up for a mean of 2.5 years, with 15 individuals converting to schizophrenia or other Diagnostic and Statistical Manual of Mental Disorders, 5th Edition diagnoses. Neurocognitive assessment was performed with the University of Pennsylvania Computerized Neuropsychological Testing, and CHR status was assessed with the Structured Interview for Prodromal Syndromes (SIPS). Baseline scores were entered in a latent profile analysis model. Our study brought forward a four-class model on cognitive performance. One class displayed better performance, whereas the other three performed worse, all compared with controls. The class with lower executive function also had the highest score on disorganized communication (SIPS P5 = 1.36, p < 0.05), although unrelated to conversion. Among the low performers, the class significantly related to conversion (p = 0.023) had the highest score in decreased expression of emotion (SIPS N3 = 0.85, p < 0.05). Our study brings new and relevant data on non-help-seeking CHR individuals and the relationship between cognitive patterns and conversion. We have highlighted a specific cognitive signature, associated with negative symptoms, which represents a stable trait with presumed lower conversion to a psychiatric illness.

Heterogeneous trajectories in schizophrenia: insights from neurodevelopment and neuroprogression models

OBJECTIVES

The notion that schizophrenia is a neuroprogressive disorder is based on clinical perception of cumulative impairments over time and is supported by neuroimaging and biomarker research. Nevertheless, increasing evidence has indicated that schizophrenia first emerges as a neurodevelopmental disorder that could follow various pathways, some of them neuroprogressive. The objective of this review is to revisit basic research on cognitive processes and neuroimaging findings in a search for candidate keys to the intricate connections between neurodevelopment and neuroprogression in schizophrenia. In the complete panorama, schizophrenia is a neurodevelopmental disorder, possibly associated with an additional burden over the course of the disease through pathologically accelerated aging, and cognitive heterogeneity may explain the different trajectories of each patient.

The association between cytokines and psychomotor speed in a spectrum of psychotic disorders: A longitudinal study

Background

In schizophrenia, impaired psychomotor speed is a common symptom predicting worse functional outcome. Inflammation causes changes in white matter integrity, which may lead to reduced psychomotor speed. Therefore, we wanted to investigate if peripheral inflammation assessed with cytokines affected performance on psychomotor speed in patients with a spectrum of psychotic disorders.

Methods

The current study is a prospective cohort study, including participants from a pragmatic, randomised controlled trial comparing three atypical antipsychotics in patients with a spectrum of psychotic disorders. For the purposes of this sub-study, we analysed drug treatment groups collectively. Psychomotor speed was assessed at baseline, and at weeks 6, 12, 26 and 52 of follow-up, using the neuropsychological tests trail making test (TMT) A and B, and symbol coding. Serum concentration of the following cytokines were measured: interleukin (IL)-β, IL-2, IL-4, IL-6, IL-10, IL12 p70, IL-17a, interferon (IFN)-γ and tumor necrosis factor (TNF)-α. Blood samples were collected at baseline and after 1, 3, 6, 12, 26, 39 and 52 weeks. We analysed the effect of cytokines levels on psychomotor speed over time in linear mixed effects models.

Results

In our linear mixed effects models controlling for possible confounders, IFN-γ had a significant negative effect on TMT-A and symbol coding performance. None of the other tests for psychomotor speed were significantly associated with cytokines. Overall psychomotor speed performance increased significantly across the study period while cytokine levels remained stable.

Conclusion

Our study indicates a negative association between IFN-γ and psychomotor speed, which might be of importance when understanding the mechanisms behind psychomotor deviations in psychotic disorders.

•

The cytokine interferon (IFN) – γ is related to psychomotor speed in patients with psychotic disorders.

•

For majority of cytokines, we found no significant association with psychomotor speed.

•

Cytokines remained stable during the study period of 52 weeks.

Cognitive change and antipsychotic medications: Results from a pragmatic rater-blind RCT

Cognitive impairment is a core aspect of psychotic disorders and difficult to treat. Atypical antipsychotics (AAs) might have differential effects on cognitive impairment, but rigid study designs and selective sampling limit the generalizability of existing findings. This pragmatic, semi-randomized, industry-independent study aimed to investigate and compare the effect of amisulpride, aripiprazole and olanzapine on cognitive performance in psychosis over a 12-month period controlling for diagnostic group. This sub study of the BeSt InTro study recruited adults with ongoing psychosis in the schizophrenia spectrum of disorders (ICD-10 diagnoses F20-F23, F25, F28 or F29; n = 104) from Bergen and Stavanger, Norway; and Innsbruck, Austria. Participants were randomized to amisulpride, aripiprazole, or olanzapine and they completed neuropsychological assessments at baseline, 6 weeks, 6 and 12 months. The test battery targeted working memory, verbal ability, and processing speed. We used Longitudinal mixed effect (LME) models to assess cognitive change for intention to treat (ITT) and per protocol (PP) medication groups, as well as comparing cognitive performance between F20 and non-F20 participants. The sample baseline global cognitive performance t-score was 42.20. Global performance improved significantly to every follow-up, including for the F20 group. There were however no significant differences in cognitive change over time between neither ITT nor PP medication groups.

Reaction Time and Visual Memory in Connection with Alcohol Use in Schizophrenia and Schizoaffective Disorder

The purpose of this study was to explore the association between cognition and hazardous drinking and alcohol use disorder in schizophrenia and schizoaffective disorder. Cognition is more or less compromised in schizophrenia, and schizoaffective disorder and alcohol use might aggravate this phenomenon. The study population included 3362 individuals from Finland with diagnoses of schizophrenia or schizoaffective disorder. Hazardous drinking was screened with the AUDIT-C (Alcohol Use Disorders Identification Test for Consumption) screening tool. Alcohol use disorder (AUD) diagnoses were obtained from national registrar data. Participants performed two computerized tasks from the Cambridge Automated Neuropsychological Test Battery (CANTAB) on a tablet computer: The Five-Choice Serial Reaction Time Task (5-CSRTT) or the reaction time (RT) test and the Paired Associative Learning (PAL) test. The association between alcohol use and the RT and PAL tests was analyzed with log-linear regression and logistic regression, respectively. After adjustment for age, education, housing status, and the age at which the respondents had their first psychotic episodes, hazardous drinking was associated with a lower median RT in females and less variable RT in males, while AUD was associated with a poorer PAL test performance in terms of the total errors adjusted scores (TEASs) in females. Our findings of positive associations between alcohol and cognition in schizophrenia and schizoaffective disorder are unique.

Oxidative-Antioxidant Imbalance and Impaired Glucose Metabolism in Schizophrenia

Schizophrenia is a neurodevelopmental disorder featuring chronic, complex neuropsychiatric features. The etiology and pathogenesis of schizophrenia are not fully understood. Oxidative-antioxidant imbalance is a potential determinant of schizophrenia. Oxidative, nitrosative, or sulfuric damage to enzymes of glycolysis and tricarboxylic acid cycle, as well as calcium transport and ATP biosynthesis might cause impaired bioenergetics function in the brain. This could explain the initial symptoms, such as the first psychotic episode and mild cognitive impairment. Another concept of the etiopathogenesis of schizophrenia is associated with impaired glucose metabolism and insulin resistance with the activation of the mTOR mitochondrial pathway, which may contribute to impaired neuronal development. Consequently, cognitive processes requiring ATP are compromised and dysfunctions in synaptic transmission lead to neuronal death, preceding changes in key brain areas. This review summarizes the role and mutual interactions of oxidative damage and impaired glucose metabolism as key factors affecting metabolic complications in schizophrenia. These observations may be a premise for novel potential therapeutic targets that will delay not only the onset of first symptoms but also the progression of schizophrenia and its complications.