Psychosocial stress and psychosis. A review of the neurobiological mechanisms and the evidence for gene-stress interaction

Coronavirus Awareness and Mental Health: Clinical Symptoms and Attitudes Toward Seeking Professional Psychological Help

The current study analyzed the relationship between Coronavirus (COVID-19) Awareness, mental health, and willingness to seek professional psychological help. This was made through a quantitative approach, using online questionnaires to collect data from 855 subjects. The questionnaires included the Brief Symptom Inventory (BSI-53) to measure mental health indicators, the Attitudes Toward Seeking Professional Psychological Help Scale-Short Form, and the Coronavirus Awareness Scale-10 (CAS-10). An Exploratory Factor Analysis suggests that three factors underlie the CAS-10: Coronavirus Concern, Exaggerated Perception, and Immunity Perception. Results indicate a significant positive correlation between Coronavirus Concern and both general anxiety and phobic anxiety symptoms. Immunity Perception is positively related to paranoid ideation and psychotic symptoms. A Mediation Analysis determined that Coronavirus Concern has a significant positive direct effect on Openness to Seeking Psychological Treatment (OSPT), while Exaggerated Perception and Immunity Perception scores have significant direct negative effects on the Value and Need in Seeking Treatment (VNST) scores. Indirectly, the relationship between Coronavirus Concern and OPST is significantly mediated by anxiety symptoms. Similar results were found for the VNST subscale. There is a negative significant effect of Immunity Perception over OSPT mediated by Paranoid Ideation. However, the overall model only achieved small r 2 coefficients for the OSPT (0.060) and VNST (0.095) scores. Comparisons in Coronavirus Awareness between sex, age, and the presence of children and older adults at home were also made. These results are discussed regarding their practical implications for mental health providers and policymakers.

Environmental Risk Factors and Psychotic-like Experiences in Children Aged 9-10

OBJECTIVE

Research implicates environmental risk factors, including correlates of urbanicity, deprivation, and environmental toxins, in psychotic-like experiences (PLEs). The current study examined associations between several types of environmental risk factors and PLEs in school-age children, whether these associations were specific to PLEs or generalized to other psychopathology, and examined possible neural mechanisms for significant associations.

METHOD

The current study used cross-sectional data from 10,328 children 9-10 years old from the Adolescent Brain Cognitive Development (ABCD) Study. Hierarchical linear models examined associations between PLEs and geocoded environmental risk factors and whether associations generalized to internalizing/externalizing symptoms. Mediation models examined evidence of structural magnetic resonance imaging abnormalities (eg, intracranial volume) potentially mediating associations between PLEs and environmental risk factors.

RESULTS

Specific types of environmental risk factors, namely, measures of urbanicity (eg, drug offense exposure, less perception of neighborhood safety), deprivation (eg, overall deprivation, poverty rate), and lead exposure risk, were associated with PLEs. These associations showed evidence of stronger associations with PLEs than internalizing/externalizing symptoms (especially overall deprivation, poverty, drug offense exposure, and lead exposure risk). There was evidence that brain volume mediated between 11% and 25% of associations of poverty, perception of neighborhood safety, and lead exposure risk with PLEs.

CONCLUSION

Although in the context of cross-sectional analyses, this evidence is consistent with neural measures partially mediating the association between PLEs and environmental exposures. This study also replicated and extended recent findings of associations between PLEs and environmental exposures, finding evidence for specific associations with correlates of urbanicity, deprivation, and lead exposure risk.

Perceived skin tone discrimination and psychotic experiences among Black Americans: Findings from the National Survey of American Life

BACKGROUND

Black Americans face significant discrimination, which has been linked to risk for psychotic experiences. However, fewer studies have examined whether perceived skin tone discrimination is associated with psychotic experiences.

METHODS

Drawing data from the National Survey of American Life (NSAL), we used multivariable logistic regression to examine the associations between perceived skin tone discrimination (from Blacks and Whites) and psychotic experiences, adjusting for sociodemographic covariates, common mental disorders, and major discriminatory events.

RESULTS

In bivariate regression models, a one-unit increase in frequency of perceived skin tone discrimination from Blacks was associated with a 24% increase in odds of having any lifetime psychotic experience (AOR: 1.24; 95% CI: 1.11-1.38). A one-unit increase in frequency of perceived skin tone discrimination from Whites was associated with an 18% increase in odds of having any lifetime psychotic experience (AOR: 1.18; 95% CI: 1.03-1.34). When examining perceived skin tone discrimination from Blacks and Whites in the same models, only perceived skin tone discrimination from Blacks was significantly associated with lifetime psychotic experiences, adjusting for sociodemographic characteristics, common metal disorders, and major discriminatory events. Perceived skin tone discrimination was associated with lifetime hallucinatory experiences, but not lifetime delusional ideation.

CONCLUSION

A significant portion of the Black population reported skin tone discrimination from Blacks and Whites, which is related to lifetime psychotic experiences. Future longitudinal and qualitative studies can elaborate on these findings and further contextualize skin tone discrimination and its health effects.

Prepubertal Environmental Enrichment Prevents Dopamine Dysregulation and Hippocampal Hyperactivity in MAM Schizophrenia Model Rats

BACKGROUND

Schizophrenia (SCZ) is a neurodevelopmental disorder with a progressive, prolonged course. Early prevention for SCZ is promising but overall lacks support from preclinical evidence. Previous studies have tested environmental enrichment (EE) in certain models of SCZ and discovered a broadly beneficial effect in preventing behavioral abnormalities relevant, yet not specific, to the disorder. Nonetheless, whether EE can prevent dopamine (DA) dysregulation, a hallmark of psychosis and SCZ, had not been tested.

METHODS

Using the MAM (methylazoxymethanol acetate) rat model of schizophrenia and saline-treated control animals, we investigated the long-term electrophysiological effects of prepubertal (postnatal day 21-40) EE on DA neurons, pyramidal neurons in the ventral hippocampus, and projection neurons in the basolateral amygdala. Anxiety-related behaviors in the elevated plus maze and locomotor responses to amphetamine were also analyzed.

RESULTS

Prepubertal EE prevented the increased population activity of DA neurons and the associated increase in locomotor response to amphetamine. Prepubertal EE also prevented hyperactivity in the ventral hippocampus but did not prevent hyperactivity in the basolateral amygdala. Anxiety-like behaviors in MAM rats were not ameliorated by prepubertal exposure to EE.

CONCLUSIONS

Twenty-day prepubertal EE is sufficient to prevent DA hyperresponsivity in the MAM model, measured by electrophysiological recordings and locomotor response to amphetamine. This effect is potentially mediated by normalizing excessive firing in the ventral hippocampus without affecting anxiety-like behaviors and basolateral amygdala firing. This study identified EE as a useful preventative approach that may protect against the pathophysiological development of SCZ.

Mental health disorders as cooccuring and predictive factors of psychotic disorders in sexually abused children

BACKGROUND

Little is known about the factors associated with psychosis in sexually abused children. Many factors have been associated with both sexual abuse and psychosis, and some mental health disorders have been identified as implied in the relationship between childhood trauma and psychosis.

OBJECTIVES

This study aims to identify factors cooccurring with psychotic disorders in sexually abused youth and to determine which predict the development of psychosis in this population.

PARTICIPANTS AND SETTING

Children with a corroborated report of sexual abuse (n = 882) at a Child Protection Agency (CPA) between 2000 and 2010 and whose health data could be retrieved from public health databases were selected for this study.

METHODS

A prospective matched-cohort design was used, with administrative databases from a CPA and a public health system. Logistic regressions were performed to determine which mental health diagnoses were associated with, and which predicted, psychotic disorders.

RESULTS

Logistic regressions revealed that personality disorders were significantly associated with psychotic disorders whereas substance misuse disorders and intellectual disability significantly predicted psychotic disorders.

CONCLUSIONS

Psychotic disorders and personality disorders appear concomitantly in sexually abused youth. Having received a substance misuse disorder diagnosis increases the risk of developing a psychotic disorder in sexually abused youth. Health professionals should be aware of those risk factors to help reduce the severity of youth sexual abuse consequences and, ultimately, prevent psychosis.

EEG Microstates and Psychosocial Stress During an Exchange Year

The well-known stress vulnerability model of psychosis assumes that psychotic episodes result from the coincidence of individual trait dispositions and triggering stressors. We thus hypothesized that a transient psychosocial stressor would not only increase the number of and stress caused by psychosis-like symptoms (like delusion-like symptoms or auditory hallucinations) in healthy subjects but also elicit changes in EEG microstates that have been related to the presence of psychotic symptoms in patients with schizophrenia. Considering a radical change of one’s psychosocial environment as a significant stressor, we analyzed psychotic symptoms and EEG microstate data in teenage exchange-students at an early and a later phase of their stay. The subjects experienced a small and transient, but significant increase of stress by psychosis-like symptoms. These changes in mental state were associated with increases in microstate class A, which has previously been related to unspecific stress. microstate classes C and D, which have consistently been found to be altered in patients with psychosis, were found unaffected by the time of the recording and the subjective stress experiences. Therefore, we conclude that microstate class A appears to be a psychosis independent and rather general correlate of psychosocial stress, whereas changes in microstate classes C and D seem to be more specifically tied to the presence of psychotic symptoms.

Urban upbringing and psychotic experiences in the United States: A racial and geographic comparison

Urban upbringing has been associated with greater risk for psychotic experiences, though research is needed to confirm whether this is true in the U.S., and whether the association depends on race, type of experience, and region of the country. We analyzed data from the National Comorbidity Survey Replication (White respondents only) and the National Survey of American Life (Black respondents). Multivariable logistic regression models found that urban upbringing was not significantly associated with lifetime psychotic experiences for Whites, but was significantly associated with lower odds for Blacks, adjusting for socio-demographic covariates and common mental disorders. Rural upbringing was associated with greater odds of lifetime auditory hallucinatory experiences for Blacks. Exploratory analyses suggested growing up in a large city or 'other' environment were associated with greater odds of lifetime psychotic experiences among Whites currently residing in the Northeast, but lower odds among Whites residing in the South. For Blacks currently residing in the West, rural upbringing was associated with significantly greater odds of lifetime psychotic experiences when compared with growing up in a large city. White and Blacks may have different lived experiences in urban and rural settings, calling for more race- and location- specific research to explain these diverging patterns.

Increased RNA editing in maternal immune activation model of neurodevelopmental disease

The etiology of major neurodevelopmental disorders such as schizophrenia and autism is unclear, with evidence supporting a combination of genetic factors and environmental insults, including viral infection during pregnancy. Here we utilized a mouse model of maternal immune activation (MIA) with the viral mimic PolyI:C infection during early gestation. We investigated the transcriptional changes in the brains of mouse fetuses following MIA during the prenatal period, and evaluated the behavioral and biochemical changes in the adult brain. The results reveal an increase in RNA editing levels and dysregulation in brain development-related gene pathways in the fetal brains of MIA mice. These MIA-induced brain editing changes are not observed in adulthood, although MIA-induced behavioral deficits are observed. Taken together, our findings suggest that MIA induces transient dysregulation of RNA editing at a critical time in brain development.

The relevance of chronic stress for the acute stress reaction in people at elevated risk for psychosis

BACKGROUND

Theoretical models and empirical evidence suggest that alterations of the acute stress reaction are a vulnerability indicator of psychosis. However, more studies are needed that use laboratory stressors and a multimodal assessment of the stress reaction. Furthermore, it needs to be clarified whether alterations of the acute stress reaction result from the chronic stress level.

METHODS

We recruited participants at familial (n = 32) and symptomatic risk (n = 43) for psychosis and a low-risk control group (n = 35). We assessed their chronic stress levels (self-report, hair cortisol concentrations) and self-reported (subjective, affective, paranoia) as well as physiological (heart rate, skin conductance level, cortisol) reactions to the Trier Social Stress Test.

RESULTS

The groups did not differ in their acute stress reaction but both at-risk groups showed higher levels of self-reported chronic stress. Chronic stress predicted changes in negative affect, paranoia and skin conductance level in the total sample.

CONCLUSIONS

We could not confirm that alterations of the acute stress reaction are an early vulnerability indicator of psychosis and conclude that they might develop at a later time-point on the trajectory to psychosis. The high chronic stress level of the at-risk groups might constitute an intermediate state that increases the likelihood of altered stress reactions in later risk stages. To test this, future work needs to investigate the temporal order between chronic stress levels, acute stress reactions and symptom development across the psychosis continuum.

Urbanicity: The need for new avenues to explore the link between urban living and psychosis

AIM

A growing body of evidence suggests that urban living contributes to the development of psychosis. However, the mechanisms underlying this phenomenon remain unclear. This paper aims to explore the best available knowledge on the matter, identify research gaps and outline future prospects for research strategies.

METHOD

A comprehensive literature survey on the main computerized medical research databases, with a time limit up to August 2017 on the issue of urbanicity and psychosis has been conducted.

RESULTS

The impact of urbanicity may result from a wide range of factors (from urban material features to stressful impact of social life) leading to "urban stress." The latter may link urban upbringing to the development of psychosis through overlapping neuro- and socio-developmental pathways, possibly unified by dopaminergic hyperactivity in mesocorticolimbic system. However, "urban stress" is poorly defined and research based on patients' experience of the urban environment is scarce.

CONCLUSIONS

Despite accumulated data, the majority of studies conducted so far failed to explain how specific factors of urban environment combine in patients' daily life to create protective or disruptive milieus. This undermines the translation of a vast epidemiological knowledge into effective therapeutic and urbanistic developments. New studies on urbanicity should therefore be more interdisciplinary, bridging knowledge from different disciplines (psychiatry, epidemiology, human geography, urbanism, etc.) in order to enrich research methods, ensure the development of effective treatment and preventive strategies as well as create urban environments that will contribute to mental well-being.

Childhood adversity and psychosis: a systematic review of bio-psycho-social mediators and moderators

The association between childhood adversity (CA) and psychosis has been extensively investigated in recent years. An increasing body of research has also focused on the mediating or moderating role of biological and psychological mechanisms, as well as other risk factors that might account for the link between CA and psychosis. We conducted a systematic search of the PsychINFO, Embase, Ovid, and Web of Science databases for original articles investigating the role of genetic vulnerabilities, environmental factors, psychological and psychopathological mechanisms in the association between CA and psychosis up to August 2019. We included studies with individuals at different stages of the psychosis continuum, from subclinical psychotic experiences to diagnosed disorders. From the 28 944 records identified, a total of 121 studies were included in this review. Only 26% of the studies identified met the criteria for methodological robustness. Overall, the current evidence suggests that CA may be associated with psychosis largely independently of genetic vulnerabilities. More consistent and robust evidence supports interaction between early and recent adversities, as well as the mediating role of attachment and mood symptoms, which is suggestive of an affective pathway between CA and psychosis across the continuum from subclinical experiences to diagnosable disorder. This review highlighted numerous methodological issues with the existing literature, including selection bias, heterogeneity of measurement instruments utilised, and lack of control for potential confounders. Future research should address these limitations to more accurately estimate mediation and moderation effects on the CA-psychosis association to inform the development of preventive interventions.

Intranasal oxytocin increases heart-rate variability in men at clinical high risk for psychosis: a proof-of-concept study

Autonomic nervous system (ANS) dysfunction (i.e., increased sympathetic and/or decreased parasympathetic activity) has been proposed to contribute to psychosis vulnerability. Yet, we still lack directed therapeutic strategies that improve ANS regulation in psychosis or at-risk states. The oxytocin system constitutes a potential therapeutic target, given its role in ANS regulation. However, whether intranasal oxytocin ameliorates autonomic regulation during emerging psychosis is currently unknown. We pooled together two datasets, one of 30 men at clinical high risk for psychosis (CHR-P), and another of 17 healthy men, who had participated in two double-blinded, placebo-controlled, randomised, crossover MRI studies with similar protocols. All participants self-administered 40 IU of intranasal oxytocin or placebo using a nasal spray. We recorded pulse plethysmography during a period of 8 min at about 1 h post dosing and estimated heart rate (HR) and high-frequency HR variability (HF-HRV), an index of cardio-parasympathetic activity. CHR-P and healthy men did not differ at resting HR or HF-HRV under placebo. We found a significant condition × treatment effect for HF-HRV, showing that intranasal oxytocin, compared with placebo, increased HF-HRV in CHR-P but not in healthy men. The main effects of treatment and condition were not significant. In this proof-of-concept study, we show that intranasal oxytocin increases cardio-parasympathetic activity in CHR-P men, highlighting its therapeutic potential to improve autonomic regulation in this clinical group. Our findings support the need for further research on the preventive and therapeutic potential of intranasal oxytocin during emerging psychosis, where we lack effective treatments.

Metabolic dysfunctions in the kynurenine pathway, noradrenergic and purine metabolism in schizophrenia and bipolar disorders

BACKGROUND

We aimed at exploring potential pathophysiological processes across psychotic disorders, applying metabolomics in a large and well-characterized sample of patients and healthy controls.

METHODS

Patients with schizophrenia and bipolar disorders (N = 212) and healthy controls (N = 68) had blood sampling with subsequent metabolomics analyses using electrochemical coulometric array detection. Concentrations of 52 metabolites including tyrosine, tryptophan and purine pathways were compared between patients and controls while controlling for demographic and clinical characteristics. Significant findings were further tested in medication-free subsamples.

RESULTS

Significantly decreased plasma concentrations in patients compared to healthy controls were found for 3-hydroxykynurenine (3OHKY, p = 0.0008), xanthurenic acid (XANU, p = 1.5×10-5), vanillylmandelic acid (VMA, p = 4.5×10-5) and metanephrine (MN, p = 0.0001). Plasma concentration of xanthine (XAN) was increased in the patient group (p = 3.5×10-5). Differences of 3OHKY, XANU, VMA and XAN were replicated across schizophrenia spectrum disorders and bipolar disorders subsamples of medication-free individuals.

CONCLUSIONS

Although prone to residual confounding, the present results suggest the kynurenine pathway of tryptophan metabolism, noradrenergic and purinergic system dysfunction as trait factors in schizophrenia spectrum and bipolar disorders. Of special interest is XANU, a metabolite previously not found to be associated with bipolar disorders.

Glutamatergic and dopaminergic function and the relationship to outcome in people at clinical high risk of psychosis: a multi-modal PET-magnetic resonance brain imaging study

Preclinical models of psychosis propose that hippocampal glutamatergic neuron hyperactivity drives increased striatal dopaminergic activity, which underlies the development of psychotic symptoms. The aim of this study was to examine the relationship between hippocampal glutamate and subcortical dopaminergic function in people at clinical high risk for psychosis, and to assess the association with the development of psychotic symptoms. ¹H-MRS was used to measure hippocampal glutamate concentrations, and ¹⁸F-DOPA PET was used to measure dopamine synthesis capacity in 70 subjects (51 people at clinical high risk for psychosis and 19 healthy controls). Clinical assessments were undertaken at baseline and follow-up (median 15 months). Striatal dopamine synthesis capacity predicted the worsening of psychotic symptoms at follow-up (r = 0.35; p < 0.05), but not transition to a psychotic disorder (p = 0.22), and was not significantly related to hippocampal glutamate concentration (p = 0.13). There were no differences in either glutamate (p = 0.5) or dopamine (p = 0.5) measures in the total patient group relative to controls. Striatal dopamine synthesis capacity at presentation predicts the subsequent worsening of sub-clinical total and psychotic symptoms, consistent with a role for dopamine in the development of psychotic symptoms, but is not strongly linked to hippocampal glutamate concentrations.

How environments get to the skin: biosensory ethnography as a method for investigating the relation between psychosis and the city

Epidemiological research in psychiatry has established robust evidence of the link between urban living and psychosis, but the situated experience of the city, as well as the precise ecology of psychosis remain largely unexplored. In this context, the aim of this paper is to discuss the productive potential of a ‘re-vitalized’ biosocial geographical thinking and researching on urban mental health. We do so through a methodological proposition. First, we discuss the need for a biosocial approach to the city/psychosis nexus and argue that a broader biological view, beyond epigenetics and neurosciences and a more precise investigation of ‘the social’ need to be developed. Second, a telling and recurring motto of recent reflections on biosocial processes is to understand how the environment or the social ‘gets under the skin’. We suggest examining a specific place in this pathway, the skin itself. This leads us to expose a methodology using electrodermal activity (EDA), combined with ethnographic observations and interviews, as a strategy for analysing ecological processes in psychosis. In doing so, we discuss the potential of ‘biosensory ethnographies’ in studies of urban mental health and more broadly as a biosocial approach to the geography of health.

Early Detection of the Risk of Developing Psychiatric Disorders: A Study of 461 Chinese University Students under Chronic Stress

Chronic stress, a characteristic of modern time, has a significant impact on general health. In the context of psychiatric disorders, insufficient coping behavior under chronic stress has been linked to higher rates of (1) depressive symptoms among subjects of the general population, (2) relapse among patients under treatment for clinical depression, and (3) negative symptoms among subjects with an elevated vulnerability to psychosis. In this normative study we assessed basic coping behavior among 461 Chinese freshman university students along with their consumption behavior and general health in terms of regular exercises, physical health, psychosomatic disturbances, and mental health. The assessments relied on two instruments that have already demonstrated their capability of (1) reliably detecting insufficient coping behavior under chronic stress and (2) reliably quantifying the interrelation between coping behavior and mental health in the Western world. Thus, we aimed to complement existing data and to develop a generally available, socioculturally independent tool that can be used for the early detection of subjects with an elevated risk of mental health problems. Structural analyses yielded essentially the same scales "activity" and "defeatism" as previous studies on 2,500 students from Switzerland, Italy, Spain, the USA, and Argentina. These scales explained 74.3% of the observed variance in coping behavior among the 461 Chinese students. We found highly significant correlations (p < 0.0001) between the "defeatism" scale on the one hand, and the scales "regular use of medicine," "psychosomatic disturbances," and "impaired mental health" on the other. Particularly intriguing was the finding that a neural net classifier could be constructed to identify students with the highest contributions to the interrelation between "coping behavior" and "mental health," yielding a correlation coefficient as high as r = 0.597 for the respective subgroup. Based on the normative data, an online tool for risk assessments was developed with immediate feedback to users. This study provided another piece of evidence regarding the close link between basic coping behavior and mental health, across cultures and ethnicities. In consequence, our approach to quantifying basic coping behavior, along with other risk factors, can be expected to clear the way for an "early" detection of students with an elevated risk of stress-related mental health problems, nota bene prior to the development of clinically relevant symptoms. The socioeconomic impact of the potential prevention of depressive -disorders, and psychiatric disorders in general, may be enormous.

Interaction of both positive and negative daily-life experiences with FKBP5 haplotype on psychosis risk

Background.

There is limited research on the interaction of both positive and negative daily-life environments with stress-related genetic variants on psychotic experiences (PEs) and negative affect (NA) across the extended psychosis phenotype. This study examined whether the FK506 binding protein 51 (FKBP5) variability moderates the association of positive and negative experiences in the moment with PEs and NA in participants with incipient psychosis and their nonclinical counterparts.

Methods.

A total of 233 nonclinical and 86 incipient psychosis participants were prompted for a 1-week period to assess their day-to-day experiences. Participants were genotyped for four FKBP5 single nucleotide polymorphisms (rs3800373, rs9296158, rs1360780, and rs9470080).

Results.

Multilevel analyses indicated that, unlike the risk haplotype, the protective FKBP5 haplotype moderated all the associations of positive experiences with diminished PEs and NA in incipient psychosis compared with nonclinical group.

Conclusions.

Participants with incipient psychosis showed symptomatic improvement when reporting positive appraisals in the interpersonal domain, which suggests that these act as a powerful coping mechanism. The fact that this occurred in daily-life underscores the clinical significance of this finding and pinpoints the importance of identifying protective mechanisms. In addition, results seem to concur with the vantage sensitivity model of gene–environment interaction, which poses that certain genetic variants may enhance the likelihood of benefiting from positive exposures.

Increased interleukin 18 activity in adolescents with early-onset psychosis is associated with cortisol and depressive symptoms

OBJECTIVE

Evidence indicates that the pathophysiology of adult psychosis involves immune dysregulation, but its associations with stress are often not considered. The inflammatory cytokine interleukin (IL)-18, which is elevated in adult schizophrenia, is suggested to be sensitive to stress. We compared the associations of IL-18 with cortisol and clinical variables in adolescents with early-onset psychosis (EOP) aged 12-18 years and age-matched healthy controls (HC).

METHOD

We measured serum IL-18, IL-18 binding protein (IL-18BP), IL-18 receptor accessory protein (IL-18RAP), IL-18 receptor 1 (IL-18R1) and cortisol, and calculated the IL-18/IL-18BP ratio in patients (n = 31) and HC (n = 60). Psychotic symptoms were assessed using the Positive and Negative Syndrome Scale and depressive symptoms by the Mood and Feelings Questionnaire-Child version (MFQ-C). Bivariate correlation analysis was used to explore relationships between IL-18/IL-18BP ratio and cortisol, depression and other clinical characteristics. Hierarchical multiple linear regression analysis was used to assess their individual contributions to the variance of the IL-18/IL-18BP ratio.

RESULTS

Patients had significantly higher IL-18 levels and IL-18/IL-18BP ratios than HC, but similar IL-18BP, IL-18RAP and IL-18R1. Both cortisol (R² change = 0.05) and the MFQ-C score (R² change = 0.09) contributed significantly to the variance in IL-18/IL-18BP ratios after controlling for confounders.

CONCLUSION

We found increased IL-18 system activity in adolescents with EOP. Cortisol and depressive symptoms each contributed to the variance in the IL-18/IL-18BP ratio. Our findings support activation of inflammatory pathways in adolescent psychosis and suggest interactions between stress, inflammation and depressive symptoms in EOP.

Decreased Plasma Levels of Growth Differentiation Factor 11 in Patients With Schizophrenia: Correlation With Psychopathology and Cognition

Schizophrenia is linked with abnormal neurodevelopment, on which growth differentiation factor 11 (GDF-11) has a great impact. However, a direct evidence linking GDF-11 to the pathophysiology of schizophrenia is still lacking. The current study aimed to investigate the relationship between plasma GDF-11 levels and both psychopathological symptoms and cognitive function in schizophrenia. Eighty-seven schizophrenia patients and 76 healthy controls were enrolled in the present study. The symptomatology of schizophrenia was evaluated using the Positive and Negative Syndrome Scale (PANSS). Cognitive function was assessed by Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) including twelve neurocognitive tests in five aspects of cognitive function. Plasma GDF-11 levels were determined by enzyme-linked immunosorbent assay (ELISA). We found that plasma levels of GDF-11 were significantly lower in schizophrenia patients relative to healthy controls. Correlation analysis showed significant negative correlations between the GDF-11 levels and the PANSS total score, the positive symptoms score, the negative symptoms score or the general score. Additionally, positive associations were observed between plasma GDF-11 levels and the visuospatial/constructional, attention, immediate memory, or delayed memory in patients. Partial correlation analysis showed that these correlations were still significant after adjusting for age, gender, education years, body mass index, duration of illness, and age of onset except for the visuospatial/constructional and attention index. Multiple regression analysis revealed that GDF-11 was an independent contributor to the immediate memory, delayed memory and RBANS total score in patients. Collectively, the correlations between plasma GDF-11 and psychopathological and cognitive symptoms suggest that abnormal GDF-11 signaling might contribute to schizophrenic psychopathology and cognitive impairments and GDF-11 could be a potential and promising biomarker for schizophrenia.

Effects of short-term cannabidiol treatment on response to social stress in subjects at clinical high risk of developing psychosis

RATIONALE

Stress is a risk factor for psychosis and treatments which mitigate its harmful effects are needed. Cannabidiol (CBD) has antipsychotic and anxiolytic effects.

OBJECTIVES

We investigated whether CBD would normalise the neuroendocrine and anxiety responses to stress in clinical high risk for psychosis (CHR) patients.

METHODS

Thirty-two CHR patients and 26 healthy controls (HC) took part in the Trier Social Stress Test (TSST) and their serum cortisol, anxiety and stress associated with public speaking were estimated. Half of the CHR participants were on 600 mg/day of CBD (CHR-CBD) and half were on placebo (CHR-P) for 1 week.

RESULTS

One-way analysis of variance (ANOVA) revealed a significant effect of group (HC, CHR-P, CHR-CBD (p = .005) on cortisol reactivity as well as a significant (p = .003) linear decrease. The change in cortisol associated with experimental stress exposure was greatest in HC controls and least in CHR-P patients, with CHR-CBD patients exhibiting an intermediate response. Planned contrasts revealed that the cortisol reactivity was significantly different in HC compared with CHR-P (p = .003), and in HC compared with CHR-CBD (p = .014), but was not different between CHR-P and CHR-CBD (p = .70). Across the participant groups (CHR-P, CHR-CBD and HC), changes in anxiety and experience of public speaking stress (all p's < .02) were greatest in the CHR-P and least in the HC, with CHR-CBD participants demonstrating an intermediate level of change.

CONCLUSIONS

Our findings show that it is worthwhile to design further well powered studies which investigate whether CBD may be used to affect cortisol response in clinical high risk for psychosis patients and any effect this may have on symptoms.

The relationship between childhood trauma, dopamine release and dexamphetamine-induced positive psychotic symptoms: a [11C]-(+)-PHNO PET study

Childhood trauma is a risk factor for psychosis. Amphetamine increases synaptic striatal dopamine levels and can induce positive psychotic symptoms in healthy individuals and patients with schizophrenia. Socio-developmental hypotheses of psychosis propose that childhood trauma and other environmental risk factors sensitize the dopamine system to increase the risk of psychotic symptoms, but this remains to be tested in humans. We used [¹¹C]-(+)-PHNO positron emission tomography to measure striatal dopamine-2/3 receptor (D_2/3R) availability and ventral striatal dexamphetamine-induced dopamine release in healthy participants (n = 24). The relationships between dexamphetamine-induced dopamine release, dexamphetamine-induced positive psychotic symptoms using the Positive and Negative Syndrome Scale (PANSS), and childhood trauma using the Childhood Trauma Questionnaire (CTQ) were assessed using linear regression and mediation analyses, with childhood trauma as the independent variable, dexamphetamine-induced dopamine release as the mediator variable, and dexamphetamine-induced symptoms as the dependent variable. There was a significant interaction between childhood trauma and ventral striatal dopamine release in predicting dexamphetamine-induced positive psychotic symptoms (standardized β = 1.83, p = 0.003), but a mediation analysis was not significant (standardized β = -0.18, p = 0.158). There were no significant effects of dopamine release and childhood trauma on change in negative (p = 0.280) or general PANSS symptoms (p = 0.061), and there was no relationship between ventral striatal baseline D_2/3R availability and positive symptoms (p = 0.368). This indicates childhood trauma and dopamine release interact to influence the induction of positive psychotic symptoms. This is not consistent with a simple sensitization hypothesis, but suggests that childhood trauma moderates the cognitive response to dopamine release to make psychotic experiences more likely.

Recovery from daily-life stressors in early and chronic psychosis

Initial affective and psychotic reactivity to daily stressors is altered in psychosis, and most notably in early psychosis. In addition to altered initial stress reactivity, results from studies using Experience Sampling Methodology (ESM) and psychophysiological measures indicate that impaired recovery from mild stressors may also be a risk factor for mental illness. The current ESM study investigated affective recovery from daily stressors in chronic psychosis patients (CP; n = 162), individuals at early stages of psychosis (EP; n = 127), and healthy volunteers (HV; n = 220) assessing fluctuations in negative affect (NA), tension, and suspiciousness ten times a day on six consecutive days. Recovery was operationalized for all three variables as the return to baseline (i.e., level at t_-1) following the first stressful event of a day (i.e., t₀). The EP group showed a delayed recovery of NA (t₁-t₃: B = 0.185; p = .007 and B = 0.228; p = .002) and suspiciousness (t₁: B = 0.223; p = .010 and B = 0.291; p = .002) compared to HV and CP, respectively. Delayed recovery was detected for tension as well (t₁-t₂: EP > HV: B = 0.242; p = .040 and EP > CP: B = 0.284; p = .023), but contrary to both other momentary states, this effect disappeared when controlling for subsequent stressful events. There were no significant differences in recovery between HV and CP. These results suggest that in EP, stressful daily events have longer-lasting effects on overall negative affect and subclinical psychotic-like experiences. Future studies should incorporate physiological and endocrine measures in order to integrate recovery patterns of the different stress systems.

HPA axis in psychotic major depression and schizophrenia spectrum disorders: Cortisol, clinical symptomatology, and cognition

The Hypothalamic Pituitary Adrenal (HPA) axis has been implicated in the pathophysiology of a variety of mood and cognitive disorders. Neuroendocrine studies have demonstrated HPA axis overactivity in major depression, a relationship of HPA axis activity to cognitive performance, and a potential role of HPA axis genetic variation in cognition. In schizophrenia differential HPA activity has been found, including higher rates of non-suppression to dexamethasone challenge and higher salivary cortisol levels, which have been a premonitory risk factor for conversion to psychosis in adolescents at risk for developing schizophrenia. The present study investigated the simultaneous roles HPA axis activity and clinical symptomatology play in poor cognitive performance. Patients with major depression with psychosis (PMD) or schizophrenia spectrum disorder (SCZ) and healthy controls (HC) were studied. All participants underwent a diagnostic interview and psychiatric ratings, a comprehensive neuropsychological battery, and overnight hourly blood sampling for cortisol. Cognitive performance did not differ between the clinical groups, though they both performed more poorly than the HC's across a variety of cognitive domains. Across all subjects, cognitive performance was negatively correlated with higher cortisol, and PMD patients had higher evening cortisol levels than did SCZ and HCs. Cortisol and clinical symptoms, as well as age, sex, and antipsychotic use predicted cognitive performance. Diathesis stress models and their links to symptomatology, cognition, and HPA function are discussed.

Inefficient neural system stabilization: a theory of spontaneous resolutions and recurrent relapses in psychosis

A striking feature of psychosis is its heterogeneity. Presentations of psychosis vary from transient symptoms with no functional consequence in the general population to a tenacious illness at the other extreme, with a wide range of variable trajectories in between. Even among patients with schizophrenia, who are diagnosed on the basis of persistent deterioration, marked variation is seen in response to treatment, frequency of relapses and degree of eventual recovery. Existing theoretical accounts of psychosis focus almost exclusively on how symptoms are initially formed, with much less emphasis on explaining their variable course. In this review, I present an account that links several existing notions of the biology of psychosis with the variant clinical trajectories. My aim is to incorporate perspectives of systems neuroscience in a staging framework to explain the individual variations in illness course that follow the onset of psychosis.

Catechol-O-methyltransferase gene expression in stress-induced and non-stress induced schizophrenia

INTRODUCTION

As schizophrenia is a complex mental disorder and the outcome of gene-gene-environmental interactions, there are different possible pathophysiological mechanisms in different schizophrenia subtypes corresponding to various risk factors. This study was aimed at examining the impact of one of the most likely interactions, that is, 'dopamine and stress', in schizophrenia pathogenesis.

METHODS

Here, we investigated the interaction between 'war-related psychological trauma' without brain trauma and catechol-O-methyltransferase gene. Using real-time PCR analysis we measured catechol-O-methyltransferase gene expression level in the blood cells of 66 male subjects in four groups, namely veteran schizophrenia patients as 'stress-exposed schizophrenia' (S-schizophrenia), their healthy brothers as 'their genetically closest relatives' (S-siblings), schizophrenia patients without any history of significant stress as 'non-stress-exposed schizophrenia' (NoS-schizophrenia), and the control group. The results were analyzed by Relative Expression Software Tool 2009 software.

RESULTS

The catechol-O-methyltransferase gene expression was not significantly different between the S-schizophrenia and NoS-schizophrenia groups. However, compared to the control group, the catechol-O-methyltransferase expression was significantly decreased in three groups of S-schizophrenia, their healthy siblings, and NoS-schizophrenia patients.

CONCLUSION

This data supports that reduced blood catechol-O-methyltransferase expression, which may be associated with higher dopamine level, is involved both in stress-induced and non-stress-induced schizophrenia.

Hair cortisol concentrations as an indicator of potential HPA axis hyperactivation in risk for psychosis

A chronic hyperactivation of the hypothalamic-pituitary-adrenal (HPA) axis is assumed to be an important indicator of vulnerability for psychosis. Despite the considerable research on this topic, putative social origins of HPA axis hyperactivation have received little attention in the literature so far. Also, the inconsistency of previous findings calls for new and reliable methods in the assessment of HPA axis activation. To address these issues, we used hair cortisol concentrations as an indicator of chronic HPA axis activation in participants at elevated risk for psychosis (clinical risk: n = 43, familial risk: n = 32) and low-risk controls (n = 35), and assessed its relation with a variety of social stressors. We also tested the interaction effect between social stressors and familial risk status on hair cortisol concentrations (moderation analysis). Participants at elevated risk for psychosis did not show significantly higher hair cortisol concentrations than low-risk controls. However, severe social stressors (child abuse experiences, traumatic events) predicted hair cortisol concentrations in the total sample. This relationship was not significantly moderated by familial risk status (as a marker of genetic risk). The results challenge the assumption that HPA axis hyperactivation is an early vulnerability indicator for psychosis but leave the possibility that it manifests only at more severe risk stages. Furthermore, the findings suggest that acquired experiences contribute to the emergence of HPA axis hyperactivation, which might occur via a gene-environment correlation rather than via a gene-environment interaction.

Acute transient psychotic disorder precipitated by Brexit vote

A man in his 40s was brought to the accident and emergency department in an acute psychotic state, 3 weeks after the European Union referendum results in the UK were declared. His mental health had deteriorated rapidly following the announcement of the results, with significant concerns about Brexit. He presented as agitated, confused and thought disordered. He had auditory hallucinations, and paranoid, referential, misidentification and bizarre delusions. He recovered completely within 2 weeks after a brief admission and treatment with olanzapine. He had experienced a similar episode of much less severity 13 years previously after major work related stress which resolved completely within a few days. He was experiencing stress related to work and family prior to the current episode which could potentially have been a contributory factor. Political events can act as major psychological stressors and have a significant impact on the mental health of people, especially those with a predisposition to develop mental illness.

The psychosis risk timeline: can we improve our preventive strategies? Part 2: adolescence and adulthood

Current understanding of psychosis development is relevant to patients' clinical outcomes in mental health services as a whole, given that psychotic symptoms can be a feature of many different diagnoses at different stages of life. Understanding the risk factors helps clinicians to contemplate primary, secondary and tertiary preventive strategies that it may be possible to implement. In this second article of a three-part series, the psychosis risk timeline is again considered, here focusing on risk factors more likely to be encountered during later childhood, adolescence and adulthood. These include environmental factors, substance misuse, and social and psychopathological aspects.

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DECLARATION OF INTEREST:

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Evidence for interaction between genetic liability and childhood trauma in the development of psychotic symptoms

PURPOSE

Whilst childhood trauma (CT) is a known risk factor across the spectrum of psychosis expression, little is known about possible interplay with genetic liability.

METHODS

The TwinssCan Study collected data in general population twins, focussing on expression of psychosis at the level of subthreshold psychotic experiences. A multilevel mixed-effects linear regression analysis was performed including 745 subjects to assess the interaction between genetic liability and CT. The Symptom Checklist-90 (SCL-90-R) score of the co-twin was used as an indirect measure of genetic liability to psychopathology, while the Childhood Trauma Questionnaire Short-Form (CTQ-SF) was used to assess CT in the domains of physical, emotional and sexual abuse, as well as physical and emotional neglect. The Community Assessment of Psychic Experience (CAPE) questionnaire was used to phenotypically characterize psychosis expression.

RESULTS

In the model using the CAPE total score, the interaction between CT and genetic liability was close to statistical significance (χ² = 5.6, df = 2, p = 0.06). Analyses of CAPE subscales revealed a significant interaction between CT and genetic liability (χ² = 8.8, df = 2, p = 0.012) for the CAPE-negative symptoms subscale, but not for the other two subscales (i.e. positive and depressive).

CONCLUSION

The results suggest that the impact of CT on subthreshold expression of psychosis, particularly in the negative subdomain, may be larger in the co-presence of significant genetic liability for psychopathology.

The Trier Social Stress Test in first episode psychosis patients: Impact of perceived stress, protective factors and childhood trauma

Psychosis has been associated with abnormalities in hypothalamic-pituitary-adrenal axis functioning, which may emerge through heightened stress sensitivity following early life adversity - ultimately resulting in illness onset and progression. The present study assessed cortisol levels during an established psychosocial stress task and their association with current stress perception, putative protective factors and adverse childhood experiences in patients with a first episode of psychosis (FEP). A total of 100 volunteers participated in the study, 57 of whom were patients with a FEP (mean age 23.9 ± 3.8) and 43 healthy community controls (mean age 23.2 ± 3.9). Salivary cortisol, heart rate and blood pressure were measured at eight time points before and after the Trier Social Stress Test. Subjective stress and protective factors were assessed with the Perceived Stress Scale, the Self-Esteem Rating Scale and the Brief COPE. Early life adversity was assessed with the Childhood Trauma Questionnaire. Patients compared to controls showed significantly lower cortisol levels (F = 7.38; p = .008) throughout the afternoon testing period, but no difference in the cortisol response to the TSST. Heart rate was elevated and protective factors were lower in patients compared to controls. Attenuated cortisol levels were associated with higher levels of perceived stress, poor protective factors and more physical neglect during childhood. Our results suggest that attenuated baseline cortisol levels and not a blunted response during an acute stress task might be an indicator of heightened stress vulnerability and poor resilience in psychosis. The possible influence of childhood adversity and antipsychotic medication is discussed.

The role of attachment anxiety in the relationship between childhood trauma and schizophrenia-spectrum psychosis

Childhood trauma (CT) is a comprehensive concept encompassing experiences of sexual, physical, and emotional abuse, and neglect during childhood and adolescence. Patients with schizophrenia-spectrum psychosis (SSP) display higher rates of CT than healthy controls. Among the potential mediators of this association, insecure attachment has gained attention and empirical validation. The present study aimed to extend existing knowledge on this field by exploring the role of the two attachment dimensions, attachment anxiety and attachment avoidance, in the CT-SSP association. A clinical sample of 63 SSP inpatients was compared to a healthy control group on CT and attachment style measures. Correlations between CT, attachment dimensions and psychopathology were sought. Mediation analyses were also performed to examine whether attachment anxiety and/or attachment avoidance mediated the CT-SSP association. Patients displayed higher rates of CT and insecure attachment than controls. Attachment anxiety and severity of Mother Antipathy were linked to severity of hallucinations. Attachment anxiety was recognized as the sole mediator of the CT-SSP association. Our findings suggest that individuals with severe CT and increased attachment anxiety represent a risk population warranting early clinical attention, regular monitoring and tailored therapeutic interventions aimed at reducing the psychological impact of trauma.

Perceived Racial Discrimination and Pain Intensity/Disability Among Economically Disadvantaged Latinos in a Federally Qualified Health Center: The Role of Anxiety Sensitivity

The present study examined the role of anxiety sensitivity (AS; fear of the negative consequences of anxiety) in the relation between perceived racial discrimination and pain-related problems among Latinos seeking health services at a Federally Qualified Health Center. Participants included 145 adult Latinos (87.80% female, M_age = 38.07 years, SD = 11.98, and 96.2% reported Spanish as their first language). Results indicated that perceived racial discrimination was indirectly related to the pain intensity and pain disability through AS. These effects were evident above and beyond the variance accounted for by gender, age, marital status, educational status, employment status, years living in the United States, and number of axis I diagnoses. Overall, the present findings highlight the merit in focusing further scientific attention on the interplay between perceived racial discrimination and AS to better understand and inform interventions to reduce pain problems among Latinos in primary care.

Proteomic analysis of oxidized proteins in the brain and liver of the Nile tilapia (Oreochromis niloticus) exposed to a water-accommodated fraction of Maya crude oil

Crude oil (CO) is a super mixture of chemical compounds whose toxic effects are reported in fish species according to international guidelines. In the current study a proteomic analysis of oxidized proteins (ox) was performed on the brain and liver of Nile tilapia exposed to WAF obtained from relevant environmental loads (0.01, 0.1 and 1.0 g/L) of Maya CO. Results have shown that oxidation of specific proteins was a newly discovered organ-dependent process able to disrupt key functions in Nile tilapia. In control fish, enzymes involved on aerobic metabolism (liver aldehyde dehydrogenase and brain dihydrofolate reductase) and liver tryptophan--tRNA ligase were oxidized. In WAF-treated liver specimens, fructose-bisphosphate aldolase (FBA), β-galactosidase (β-GAL) and dipeptidyl peptidase 9 (DPP-9) were detected in oxidized form. oxDPP-9 could be favorable by reducing the risk associated with altered glucose metabolism, the opposite effects elicited by oxFBA and oxβ-GAL. oxTrypsin showed a clear adverse effect by reducing probably the hepatocyte capacity to achieve proteolysis of oxidized proteins as well as for performing the proper digestive function. Additionally, enzyme implicated in purine metabolism adenosine (deaminase) was oxidized. Cerebral enzymes of mitochondrial respiratory chain complex (COX IV, COX5B), of glycosphingolipid biosynthesis (β-N-acetylhexosaminidase), involved in catecholamines degradation (catechol O-methyltransferase), and microtubule cytoskeleton (stathmin) were oxidized in WAF-treated specimens. This response suggests, in the brain, an adverse scenario for the mitochondrial respiration process and for ATP provision as for ischemia/reoxygenation challenges. Proteomic analysis of oxidized proteins is a promising tool for monitoring environmental quality influenced by hydrocarbons dissolved in water.

Childhood Trauma in Schizophrenia: Current Findings and Research Perspectives

Schizophrenia is a severe neuropsychiatric disorder with persistence of symptoms throughout adult life in most of the affected patients. This unfavorable course is associated with multiple episodes and residual symptoms, mainly negative symptoms and cognitive deficits. The neural diathesis-stress model proposes that psychosocial stress acts on a pre-existing vulnerability and thus triggers the symptoms of schizophrenia. Childhood trauma is a severe form of stress that renders individuals more vulnerable to developing schizophrenia; neurobiological effects of such trauma on the endocrine system and epigenetic mechanisms are discussed. Childhood trauma is associated with impaired working memory, executive function, verbal learning, and attention in schizophrenia patients, including those at ultra-high risk to develop psychosis. In these patients, higher levels of childhood trauma were correlated with higher levels of attenuated positive symptoms, general symptoms, and depressive symptoms; lower levels of global functioning; and poorer cognitive performance in visual episodic memory end executive functions. In this review, we discuss effects of specific gene variants that interact with childhood trauma in patients with schizophrenia and describe new findings on the brain structural and functional level. Additive effects between childhood trauma and brain-derived neurotrophic factor methionine carriers on volume loss of the hippocampal subregions cornu ammonis (CA)4/dentate gyrus and CA2/3 have been reported in schizophrenia patients. A functional magnetic resonance imaging study showed that childhood trauma exposure resulted in aberrant function of parietal areas involved in working memory and of visual cortical areas involved in attention. In a theory of mind task reflecting social cognition, childhood trauma was associated with activation of the posterior cingulate gyrus, precuneus, and dorsomedial prefrontal cortex in patients with schizophrenia. In addition, decreased connectivity was shown between the posterior cingulate/precuneus region and the amygdala in patients with high levels of physical neglect and sexual abuse during childhood, suggesting that disturbances in specific brain networks underlie cognitive abilities. Finally, we discuss some of the questionnaires that are commonly used to assess childhood trauma and outline possibilities to use recent biostatistical methods, such as machine learning, to analyze the resulting datasets.

Childhood abuse and psychotic experiences in adulthood: findings from a 35-year longitudinal study

BACKGROUND

The extent to which exposure to childhood sexual and physical abuse increases the risk of psychotic experiences in adulthood is currently unclear.AimsTo examine the relationship between childhood sexual and physical abuse and psychotic experiences in adulthood taking into account potential confounding and time-dynamic covariate factors.

METHOD

Data were from a cohort of 1265 participants studied from birth to 35 years. At ages 18 and 21, cohort members were questioned about childhood sexual and physical abuse. At ages 30 and 35, they were questioned about psychotic experiences (symptoms of abnormal thought and perception). Generalised estimating equation models investigated covariation of the association between abuse exposure and psychotic experiences including potential confounding factors in childhood (socioeconomic disadvantage, adverse family functioning) and time-dynamic covariate factors (mental health, substance use and life stress).

RESULTS

Data were available for 962 participants; 6.3% had been exposed to severe sexual abuse and 6.4% to severe physical abuse in childhood. After adjustment for confounding and time-dynamic covariate factors, those exposed to severe sexual abuse had rates of abnormal thought and abnormal perception symptoms that were 2.25 and 4.08 times higher, respectively than the 'no exposure' group. There were no significant associations between exposure to severe physical abuse and psychotic experiences.

CONCLUSIONS

Findings indicate that exposure to severe childhood sexual (but not physical) abuse is independently associated with an increased risk of psychotic experiences in adulthood (particularly symptoms of abnormal perception) and this association could not be fully accounted for by confounding or time-dynamic covariate factors.Declaration of interestNone.

Interaction between childhood adversity and functional polymorphisms in the dopamine pathway on first-episode psychosis

BACKGROUND

There is consistent evidence of a cumulative relationship between childhood adversity and psychosis, with number of adversities experienced increasing the probability of psychosis onset. It is possible that genetic factors moderate the association between childhood adversity and psychosis, potentially by influencing how an individual reacts biologically and/or psychologically following exposure to adversity, in such a way as to set them off on the path to psychosis. However, identifying the specific genetic variants involved and how they interact with childhood adversity remains challenging. We examined whether the association between cumulative exposure to childhood adversity and development of psychotic disorder was moderated by the COMT Val¹⁵⁸Met, AKT1 rs2494732 or DRD2 rs1076560 polymorphisms, known to affect dopamine levels.

METHODS

Participants were 285 first-presentation psychosis cases and 256 geographically-matched controls drawn from the Genetics and Psychosis (GAP) study. Childhood adversity was assessed using the Childhood Experience of Care and Abuse Questionnaire (CECA.Q) and blood- and cheek-derived genotype data were collected.

RESULTS

Our findings revealed no main effect of COMT Val¹⁵⁸Met, AKT1 rs2494732 and DRD2 rs1076560 polymorphisms on psychosis case status or reports of childhood adversity. Individuals reporting a history of multiple adversities were more likely to be psychosis patients than controls, regardless of their genetic risk. There was no evidence of candidate genotype by childhood adversity interactions in relation to psychosis onset.

CONCLUSION

These findings did not provide evidence of a possible role of COMT Val¹⁵⁸Met, AKT1 rs2494732 or DRD2 rs1076560 genotypes in modifying the association between childhood adversity and onset of psychosis.

Age-Associated Deviations of Amygdala Functional Connectivity in Youths With Psychosis Spectrum Disorders: Relevance to Psychotic Symptoms

OBJECTIVE

The authors created normative growth charts of amygdala functional connectivity in typically developing youths, assessed age-associated deviations of these trajectories in youths with psychosis spectrum disorders, and explored how these disruptions are related to clinical symptomatology.

METHODS

Resting-state functional neuroimaging data from four samples (three cross-sectional, one longitudinal) were collected for 1,062 participants 10-25 years of age (622 typically developing control youths, 194 youths with psychosis spectrum disorders, and 246 youths with other psychopathology). The authors assessed deviations in the psychosis spectrum and other psychopathology groups in age-related changes in resting-state functional MRI amygdala-to-whole brain connectivity from a normative range derived from the control youths. The authors explored relationships between age-associated deviations in amygdala connectivity and positive symptoms in the psychosis spectrum group.

RESULTS

Normative trajectories demonstrated significant age-related decreases in centromedial amygdala connectivity with distinct regions of the brain. In contrast, the psychosis spectrum group failed to exhibit any significant age-associated changes between the centromedial amygdala and the prefrontal cortices, striatum, occipital cortex, and thalamus (all q values <0.1). Age-associated deviations in centromedial amygdala-striatum and centromedial amygdala-occipital connectivity were unique to the psychosis spectrum group and were not observed in the other psychopathology group. Exploratory analyses revealed that greater age-related deviation in centromedial amygdala-thalamus connectivity was significantly associated with increased severity of positive symptoms (r=0.19; q=0.05) in the psychosis spectrum group.

CONCLUSIONS

Using neurodevelopmental growth charts to identify a lack of normative development of amygdala connectivity in youths with psychosis spectrum disorders may help us better understand the neural basis of affective impairments in psychosis, informing prediction models and interventions.

Reductions in reported persecutory ideation and psychotic-like experiences during exposure therapy for posttraumatic stress disorder

While psychotic-like experiences (PLEs), including persecutory ideation and auditory or visual hallucinations, are common in PTSD, questions remain about their relationships to core PTSD symptoms and responsiveness to treatment. This study examined data from a waitlist (WL) controlled clinical study of the effect of virtual reality (VR) and prolonged exposure (PE) in a sample of active-duty service members with deployment-related trauma (n = 161). PLEs were assessed and examined with regard to their responsiveness to trauma focused treatment (combining conditions) relative to the WL, as well as their relationships to PTSD symptoms. Persecutory ideation symptoms, which were most closely related to PTSD Cluster C (avoidance and numbing) symptoms, were reduced post-treatment in the trauma-focused condition relative to WL. Auditory and visual hallucinations-which were most closely associated with PTSD re-experiencing-decreased from baseline to post-treatment assessments for WL and exposure therapy participants. The presence of PLEs at baseline did not predict a reduced PTSD symptom response to treatment. Trauma-focused treatments appear effective in addressing psychotic-like experiences that can emerge in individuals with PTSD.

Cognitive Restructuring and Graded Behavioral Exposure for Persecutory Paranoia and Agoraphobic Anxiety in Complex Psychosis

Cognitive behavioral models of psychosis assert the notion of cognitive mediation, in which threat-oriented subjective misinterpretations of anomalous experiences lead to increased levels of emotional distress. Thus, paranoid appraisals of auditory hallucinations often result in hypervigilance and associated anxiety. The prevalence of diagnostic comorbidity between psychosis and anxiety disorders has been shown to be considerable. Among the evidence-based psychological treatments for complex mental ill-health, Cognitive Behavioral Therapy for psychosis (CBTp) has been supported with particularly promising research outcomes. Yet, despite such encouraging empirical data, the treatment provision often remains insufficient, predominantly among individuals with more acute presentations. Likewise, literature demonstrating the actual utilization of CBTp with complex psychoses appears above all relevant to the daily clinical practice in the specialism of severe mental ill-health. This methodologically rigorous case study describes a successful implementation of CBTp undertaken with a socially withdrawn individual diagnosed with paranoid schizophrenia and comorbid agoraphobic anxiety disorder. The intervention focused on cognitive restructuring of paranoid appraisals of voices and graded behavioral exposure to anxiety-inducing stimuli. Standardized measurement, behavior frequency sampling, and subjective data were utilized to evaluate the outcomes, indicating a considerable reduction in both paranoia and associated anxiety, and an overall improvement in the client’s behavioral and interpersonal functioning. The article highlights the importance of direct intellectual engagement with the content of paranoia, alongside methodically facilitated graded behavioral exposure and response prevention in the treatment of severe, socially debilitating psychoses with comorbid mood disorders.

Past-year relational victimization is associated with a blunted neural response to rewards in emerging adults

Anhedonia is associated with multiple forms of psychopathology, yet relatively, little is known about how anhedonia develops. Emerging evidence suggests that anhedonia is the result of interactions between life stress and the brain's reward systems, and that social stress, in particular, may drive these processes. One potent form of social stress is peer victimization, but very little research has focused on peer victimization beyond adolescence, and even less has examined the associations between peer victimization and neural response to rewards. The present study sought to identify associations between past-year history of peer victimization and neural response to rewards in emerging adults (N = 61). Relational and physical forms of victimization were assessed separately since these distinct types of social stress have different trajectories across development and different associations with psychopathology. Reward sensitivity was indexed with the event-related potential component known as the reward positivity, which was elicited using a forced-choice monetary reward guessing task. Results demonstrated that past-year relational, but not physical, victimization was associated with a blunted neural response to rewards. These findings provide insight into one potential mechanism in the etiology of anhedonia, which may, in turn, help us to better identify pathways to multiple psychopathologies.

Reported Childhood Abuse and Stress Reactivity in Psychosis: A Conceptual Replication and Exploration of Statistical Approaches

A previous study observed that reported childhood abuse moderated psychotic and emotional reactivity to stress among patients with non-affective psychotic disorder. However, that study used a type of analysis unsuited for skewed data. This study aimed (1) to replicate the study and (2) to examine whether we would obtain similar results using a statistical approach better suited to skewed data. Fifty-nine patients with non-affective psychotic disorder were examined for up to 6 days using an intensive diary method to assess levels of negative affect, psychosis, and daily-life stress. A mixed-linear regression largely replicated earlier findings, but a two-component analysis failed to replicate the moderating effect of reported childhood abuse. These results illustrate the importance of exploring different statistical approaches to skewed data. They may also indicate that stress sensitization does not offer a complete account for the effect of reported childhood abuse on psychotic symptom severity.

Exploring the moderating effects of dopaminergic polymorphisms and childhood adversity on brain morphology in schizophrenia-spectrum disorders

Genetic and environmental etiologies may contribute to schizophrenia and its associated neurobiological profile. We examined the interaction between dopaminergic polymorphisms, childhood adversity and diagnosis (schizophrenia/schizoaffective disorder) on dopamine-related brain structures. Childhood adversity histories and structural MRI data were obtained from 249 (153 schizophrenia/schizoaffective, 96 controls) participants registered in the Australian Schizophrenia Research Bank. Polymorphisms in DRD2 and COMT were genotyped and a dopaminergic risk allelic load (RAL) was calculated. Regression analysis was used to test the main and interaction effects of RAL, childhood adversity and diagnosis on volumes of dopamine-related brain structures (caudate, putamen, nucleus accumbens, dorsolateral prefrontal cortex and hippocampus). A schizophrenia/schizoaffective diagnosis showed significant main effects on bilateral hippocampus, left dorsolateral prefrontal cortex and bilateral putamen volumes. RAL showed a significant main effect on left putamen volumes. Furthermore, across the whole sample, a significant two-way interaction between dopaminergic RAL and childhood adversity was found for left putamen volumes. No brain structure volumes were predicted by a three-way interaction that included diagnosis. Our finding suggests the left putamen may be particularly sensitive to dopaminergic gene-environment interactions regardless of diagnosis. However, larger studies are needed to assess whether these interactions are more or less pronounced in those with schizophrenia/schizoaffective disorders.

Neuro-metabolite profiles of rodent models of psychiatric dysfunctions characterised by MR spectroscopy

Neuroimaging endophenotypes in animal models provide an objective and translationally-relevant alternative to cognitive/behavioral traits in human psychopathologies. Metabolic alterations, such as those involved in the glutamate-cycle, have been proposed to play a preponderant role in both depression and schizophrenia. Chronic Mild Unpredictable Stress (CMUS) and sub-chronic administration of NMDA receptor antagonist generate animal models of depression and schizophrenia, respectively. The models are based on etiologically-relevant factors related to the induction and support of these psychopathologies. To test metabolic alterations within the glutamate-cycle and in other major neurochemicals, single-voxel Magnetic Resonance Spectroscopy was recorded within the hippocampus in both rat models and control animals. Surprisingly, altered glutamate-related metabolites were observed in the CMUS model, but not NMDA-based model, as indicated by decreased glutamine and increased GABA levels. However, both models presented elevated total visible choline and inositol levels relative to controls. These results indicate the presence cell membrane metabolic alterations and inflammatory processes shared in both models, comparable to evidence presented in schizophrenia and depression and other comparable animal models. These translationally-relevant biomarkers may thus form the basis for drug-development targets in both psychopathologies.

Elevated allostatic load early in the course of schizophrenia

Stress plays a significant role in schizophrenia from disease onset to exacerbation of psychotic symptoms. Allostatic load (AL) is a measure of cumulative stress to the organism. This study is an extension of our previous work on AL and its relationship to brain structures. Here, we further determined whether elevated AL is a function of illness chronicity, or if it is already present early in the course of schizophrenia. AL was compared in schizophrenia patients early in the illness (within 5 years of disease onset), patients with chronic schizophrenia (more than 5 years of illness), and two groups of healthy controls that were age-and sex-matched to the two patient groups. This work is presented with an expanded sample and includes about two-thirds of the participants who were previously reported. We found that patients with early psychosis had significantly elevated AL score compared with their age-matched controls (p = 0.005). Chronic course patients also had elevated AL compared with age-matched controls (p = 0.003). Immune and stress hormone AL subcomponents were nominally higher in early-stage patients compared with controls (p = 0.005 and 0.04, respectively). Greater AL was also associated with more severe positive psychotic symptoms in early-stage patients (r = 0.54, p = 0.01). Elevated levels of allostatic load are already present in the early years of the schizophrenia illness, particularly in patients with more severe psychotic symptoms. AL may be a useful evaluation for the need of early intervention on psychosomatic comorbidity.

Challenges and Potential Solutions of Psychophysiological State Monitoring with Bioradar Technology

Psychophysiological state monitoring provides a promising way to detect stress and accurately assess wellbeing. The purpose of the present work was to investigate the advantages of utilizing a new unobtrusive multi-transceiver system on the accuracy of remote psychophysiological state monitoring by means of a bioradar technique. The technique was tested in laboratory conditions with the participation of 35 practically healthy volunteers, who were asked to perform arithmetic and physical workload tests imitating different types of stressors. Information about any variation in vital signs, registered by a bioradar with two transceivers, was used to detect mental or physical stress. Processing of the experimental results showed that the designed two-channel bioradar can be used as a simple and relatively easy approach to implement a non-contact method for stress monitoring. However, individual specificity of physiological responses to mental and physical workloads makes the creation of a universal stress-detector classifier that is suitable for people with different levels of stress tolerance a challenging task. For non-athletes, the proposed method allows classification of calm state/mental workload and calm state/physical workload with an accuracy of 89% and 83% , respectively, without the usage of any additional a priori information on the subject.

Gene-environment interaction between the brain-derived neurotrophic factor Val66Met polymorphism, psychosocial stress and dietary intake in early psychosis

AIM

The brain-derived neurotrophic factor (BDNF) is a major participant in the regulation of food intake and may play a role in the regulation of the stress response. We aimed to investigate whether there is a gene-environment interaction in the relationship between stress and BDNF Val66Met polymorphism in relation to dietary patterns in a sample of subjects with early psychosis.

METHODS

We studied 124 early psychotic disorder (PD) patients, 36 At-Risk Mental States (ARMS) and 62 healthy subjects (HS). Dietary patterns were examined by a dietician. Physical activity, life stress and perceived stress were assessed by validated questionnaires. BDNF Val66Met polymorphism (rs6265) was genotyped. A gene-environment interaction was tested with multiple linear regression analysis while adjusting for covariates.

RESULTS

Perceived stress was not associated with calorie intake in HS. In ARMS subjects, Met-carriers who presented low-perceived stress were associated with increased caloric intake. Conversely, those who presented high-perceived stress were associated with reduced caloric intake. In PD, perceived stress was neither associated with increased calorie intake without an effect by BDNF genotype nor a gene-environment interaction. Perceived stress was associated with food craving in PD patients, independent of genotype, and in ARMS or HS who were Val homozygous.

CONCLUSIONS

This study suggests that the common Val66Met polymorphism of the BDNF gene may modulate the relationship between life stress and calorie intake in subjects at risk for psychosis.

Exploring anxiety in schizophrenia: New light on a hidden figure

Anxiety is among the least studied features of schizophrenia, despite evidence of its significant impact on disease outcome. This work aims to investigate the anxiety construct in a sample of outpatients with schizophrenia, exploring the interplay of clinical, neurocognitive and social cognitive domains, as well as adverse childhood experiences and their relative contribute in determining anxiety. A forward stepwise regression model was performed on a sample of 68 outpatients with schizophrenia, to examine the predictive effect of different variables on anxiety. Predictors have been selected based on previous literature and include psychopathological, neurocognitive and social cognitive measures, as well as premorbid environmental factors. The analysis showed a significant contribution of childhood adverse experiences, followed by personal distress, while no significant effect was found for symptom's severity, nor global cognitive efficiency. The results show that anxiety is mainly determined by early environmental factors, as well as by socio-cognitive dimensions, such as personal distress. Data also suggest that anxiety can be considered as an independent construct, rather than as a mere epiphenomenon of the illness. The study has clinical implications as it highlights the importance of implementing both standardized assessments and group interventions specifically targeting anxiety in schizophrenia.

First break psychosis in a young military veteran with cannabis use disorder: an educational case report

Psychotropic management of a first psychotic break is challenging for many psychiatrists. The literature shows that the use of cannabis is widespread in psychotic individuals. The literature also points to young males being most at risk for substance abuse. Studies also show that obstructive sleep apnea and the stress of the military lifestyle contribute to the development of psychosis. Here, we present a case study of a young non-combat veteran with a medical history of obstructive sleep apnea who presented to the Emergency Department of a Veteran's Affairs hospital with symptoms consistent with a first psychotic break. On routine admission laboratory work, his urine toxicology screen was positive for cannabis. Given the widespread use of cannabis in individuals with psychosis, we suggest that it plays an important role in the regulation of psychosis and behavior.