Stress reactivity links childhood trauma exposure to an admixture of depressive, anxiety, and psychosis symptoms

Daily stress reactivity and risk appraisal mediates childhood parental abuse predicting adulthood psychopathology severity: An 18-year longitudinal mediation analysis

Identifying mechanisms of childhood abuse-adulthood psychopathology relations could facilitate preventive efforts, but most prior studies used cross-sectional or two-wave designs and did not test the effects of childhood maternal and paternal abuse separately. Our 18-year three-wave study thus determined if Wave 2 daily stress reactivity and risk appraisal severity mediated Wave 1 retrospectively-reported childhood maternal and paternal abuse on Wave 3 generalized anxiety disorder (GAD), major depressive disorder (MDD), panic disorder (PD), alcohol (AUD), and substance use disorder (SUD) self-rated symptom severity. Longitudinal structural equation modeling was employed, adjusting for Wave 1 psychopathology severity. Higher childhood maternal and paternal abuse consistently predicted greater future daily stress reactivity and risk appraisal, and these mediators subsequently predicted increased GAD, MDD, and PD, but not AUD and SUD severity. Daily stress reactivity and risk appraisal consistently mediated the pathways between childhood maternal and paternal abuse predicting heightened adulthood GAD, MDD, and PD (Cohen's d = 0.333-0.888) but not AUD and SUD severity. Mediation effect sizes were stronger for childhood maternal (24.5-83.0%) than paternal (19.5-56.0%) abuse as the predictor. The latent interaction between Wave 1 childhood maternal and paternal abuse did not moderate the effect of Wave 1 maternal or paternal abuse on any Wave 3 adulthood psychopathology severity through Wave 2 daily stress reactivity and risk appraisal. Our research emphasizes the urgent requirement for continuous evaluation and intervention initiatives in trauma-informed care, both in inpatient and outpatient treatment settings.

Altered brain and physiological stress responses in early psychosis

Stress is proposed to be a crucial factor in the onset and presentation of psychosis. The early stage of psychosis provides a window into how stress interacts with the emergence of psychosis. Yet, how people with early psychosis respond to stress remains unclear. The current study examined how stress responses (brain, physiological, self-report) differ in early psychosis. Forty participants (20 early psychosis [EP], 20 healthy controls [HC]) completed a stress task in the scanner that involved viewing stressful and neutral-relaxing images. Physiological responses (cortisol, heart rate) and self-report of stress were also assessed. Region of Interest analyses were conducted with brain regions previously shown to be activated during the stress task (amygdala, hippocampus, striatum, hypothalamus, prefrontal cortex [dorsolateral, ventrolateral, medial orbital]). Linear mixed models were used to test for effects of group (EP, HC) and emotion (stress, neutral-relaxing). HC had higher hippocampus activation to stress versus neutral-relaxing conditions while EP did not show a difference (group x emotion interaction, p = 0.04). There were also significant main effects of group with EP having higher amygdala activation (p = 0.01), ventrolateral prefrontal cortex activation (vlPFC, p = 0.03), self-report of stress (p = 0.01), and heart rate (p < 0.001). Our study found preliminary evidence that people with early psychosis showed heightened response to stressful and non-threatening situations, across multiple levels of stress responses. Our findings suggest a novel perspective on stress alterations in early psychosis and highlight the importance of considering both stressful and non-stressful situations.

The effects of childhood trauma on stress-related vulnerability factors and indicators of suicide risk: An ecological momentary assessment study

BACKGROUND

Childhood trauma is experienced by approximately one third of young people in the United Kingdom and has been shown to confer an increased risk for mental health difficulties in adulthood. Understanding the associations between these factors before negative health outcomes manifest in adulthood is imperative to help inform the development of interventions. The aims of this study were two-fold; first, to investigate the effects of childhood trauma on daily stress-related vulnerability factors over a period of 7 days and to test whether any observed relationships were moderated by protective or risk factors. Second, to explore the indirect effects of childhood trauma on reasons for living, optimism, daily suicide ideation, defeat and entrapment through the daily stress-related vulnerability factors.

METHODS

212 participants were recruited to an ecological momentary assessment study to complete three diaries per day for a 7-day period. Participants completed daily measures of stress, hassles, executive functioning, impulsivity, sleep quality (stress-related vulnerability factors) as well as measures of reasons for living, optimism, daily thoughts of suicide, defeat and entrapment. The Childhood Trauma Questionnaire was also completed at baseline.

RESULTS

Analyses found that childhood trauma was significantly associated with higher scores on the daily stress-related vulnerability factors and positively related to each of the daily indicators of suicide risk. The study also uncovered key pathways whereby trauma had indirect effects on reasons for living, optimism, daily thoughts of suicide, defeat and entrapment through executive functioning, impulsivity, sleep quality and stress.

LIMITATIONS

The measures of executive function and sleep were self-reported and future research ought to replicate the current findings using more objective methods.

DISCUSSION

The findings from this study highlight the complexity of childhood trauma and its damaging effects on stress-related vulnerability factors and poorer mental health outcomes. Greater understanding of pathways by which trauma may impact later health outcomes is essential for development of interventions.

The experience sampling methodology in psychosis risk states: A systematic review

The experience sampling method (ESM) is a structured diary technique, which is used to assess thoughts, mood and appraise subjective experiences in daily life. It has been recognized as a useful tool for understanding the characteristics, dynamics, and underlying mechanisms of prodromal symptoms of psychosis. The present systematic review aimed to provide a qualitative synthesis of findings provided by the ESM studies conducted in people with psychosis risk states. A systematic review of the MEDLINE, ERIC, Academic Search Ultimate, and Health Source: Nursing/Academic Edition databases, utilizing search terms related to the ESM and the risk of psychosis was conducted. Out of 1069 publication records identified, 77 studies met the inclusion criteria for the review. Data were synthesized around the following topics: 1) assessment of symptoms dynamics and social functioning; 2) assessment of the mechanisms contributing to the emergence of psychotic experiences and 3) assessment of stress sensitivity. The studies have shown that negative emotions are associated with subsequent development of paranoia. The tendency to draw hasty conclusions, aberrant salience, self-esteem, and emotion regulation were the most frequently reported mechanisms associated with the emergence of psychotic experiences. Studies using the ESM also provided evidence for the role of stress sensitivity, in the development of psychotic symptoms. The ESM has widely been applied to studies investigating psychosis risk states, using a variety of protocols. Findings from this systematic review might inform future studies and indicate potential targets for interventions.

Threat Responses in Schizophrenia: A Negative Valence Systems Framework

PURPOSE OF REVIEW

Emotions are prominent in theories and accounts of schizophrenia but are largely understudied compared to cognition. Utilizing the Research Domain Criteria (RDoC) Negative Valence Systems framework, we review the current knowledge of emotions in schizophrenia. Given the pivotal role of threat responses in theories of schizophrenia and the substantial evidence of altered threat responses, we focus on three components of Negative Valence Systems tied to threat responses: responses to acute threat, responses to potential threat, and sustained threat.

RECENT FINDINGS

Individuals with schizophrenia show altered responses to neutral stimuli during acute threat, bed nucleus of the stria terminalis connectivity in response to potential threat, and threat responses associated with sustained threat. Our review concludes that Negative Valence Systems are altered in schizophrenia; however, the level and evidence of alterations vary across the types of threat responses. We suggest avenues for future research to further understand and intervene on threat responses in schizophrenia.

Examining associations, moderators and mediators between childhood maltreatment, social functioning, and social cognition in psychotic disorders: a systematic review and meta-analysis

Childhood maltreatment (CM) has been related to social functioning and social cognition impairment in people with psychotic disorders (PD); however, evidence across different CM subtypes and social domains remains less clear. We conducted a systematic review and meta-analysis to quantify associations between CM, overall and its different subtypes (physical/emotional/sexual abuse, physical/emotional neglect), and domains of social functioning and social cognition in adults with PD. We also examined moderators and mediators of these associations. A PRISMA-compliant systematic search was performed on 24 November 2022 (PROSPERO CRD42020175244). Fifty-three studies (N = 13 635 individuals with PD) were included in qualitative synthesis, of which 51 studies (N = 13 260) with 125 effects sizes were pooled in meta-analyses. We found that CM was negatively associated with global social functioning and interpersonal relations, and positively associated with aggressive behaviour, but unrelated to independent living or occupational functioning. There was no meta-analytic evidence of associations between CM and social cognition. Meta-regression analyses did not identify any consistent moderation pattern. Narrative synthesis identified sex and timing of CM as potential moderators, and depressive symptoms and maladaptive personality traits as possible mediators between CM and social outcomes. Associations were of small magnitude and limited number of studies assessing CM subtypes and social cognition are available. Nevertheless, adults with PD are at risk of social functioning problems after CM exposure, an effect observed across multiple CM subtypes, social domains, diagnoses and illness stages. Maltreated adults with PD may thus benefit from trauma-related and psychosocial interventions targeting social relationships and functioning.

Neuroticism mediates the association between childhood abuse and the well-being of community dwelling adult volunteers

BACKGROUND

Previous studies reported that the experience of maltreatment in childhood reduces subjective well-being in adulthood and that neuroticism is negatively associated with subjective well-being. However, the interrelationship between childhood maltreatment, adult life events, neuroticism, and subjective well-being has not been analyzed to date.

METHODS

A total of 404 adult volunteers provided responses to the following questionnaires: 1) Childhood Abuse and Trauma Scale, 2) Life Experiences Survey, 3) Neuroticism Subscale of the Shortened Eysenck Personality Questionnaire-Revised, and 4) Subjective Well-Being Inventory. The path model was used to analyze possible interrelationships among these parameters.

RESULTS

The effect of childhood abuse on subjective well-being was indirect and was mediated by neuroticism. The effect of neuroticism on the negative, but not positive, change score on the Life Experiences Survey was significant. The indirect effect of neuroticism on subjective well-being was not significant via either negative or positive change scores.

CONCLUSIONS

This study demonstrated that age, subjective social status, neuroticism, and negative and positive life events were significantly associated with subjective well-being. Furthermore, using path analysis, we demonstrated the mediating role of neuroticism in the indirect effect of childhood abuse on subjective well-being.

Dose-dependent changes in real-life affective well-being in healthy community-based individuals with mild to moderate childhood trauma exposure

BACKGROUND

Childhood trauma exposures (CTEs) are frequent, well-established risk factor for the development of psychopathology. However, knowledge of the effects of CTEs in healthy individuals in a real life context, which is crucial for early detection and prevention of mental disorders, is incomplete. Here, we use ecological momentary assessment (EMA) to investigate CTE load-dependent changes in daily-life affective well-being and psychosocial risk profile in n = 351 healthy, clinically asymptomatic, adults from the community with mild to moderate CTE.

FINDINGS

EMA revealed significant CTE dose-dependent decreases in real-life affective valence (p = 0.007), energetic arousal (p = 0.032) and calmness (p = 0.044). Psychosocial questionnaires revealed a broad CTE-related psychosocial risk profile with dose-dependent increases in mental health risk-associated features (e.g., trait anxiety, maladaptive coping, loneliness, daily hassles; p values < 0.003) and a corresponding decrease in factors protective for mental health (e.g., life satisfaction, adaptive coping, optimism, social support; p values < 0.021). These results were not influenced by age, sex, socioeconomic status or education.

CONCLUSIONS

Healthy community-based adults with mild to moderate CTE exhibit dose-dependent changes in well-being manifesting in decreases in affective valence, calmness and energy in real life settings, as well as a range of established psychosocial risk features associated with mental health risk. This indicates an approach to early detection, early intervention, and prevention of CTE-associated psychiatric disorders in this at-risk population, using ecological momentary interventions (EMI) in real life, which enhance established protective factors for mental health, such as green space exposure, or social support.

Disentangling heterogeneity of psychosis expression in the general population: sex-specific moderation effects of environmental risk factors on symptom networks

BACKGROUND

Psychosis expression in the general population may reflect a behavioral manifestation of the risk for psychotic disorder. It can be conceptualized as an interconnected system of psychotic and affective experiences; a so-called 'symptom network'. Differences in demographics, as well as exposure to adversities and risk factors, may produce substantial heterogeneity in symptom networks, highlighting potential etiological divergence in psychosis risk.

METHODS

To explore this idea in a data-driven way, we employed a novel recursive partitioning approach in the 2007 English National Survey of Psychiatric Morbidity (N = 7242). We sought to identify 'network phenotypes' by explaining heterogeneity in symptom networks through potential moderators, including age, sex, ethnicity, deprivation, childhood abuse, separation from parents, bullying, domestic violence, cannabis use, and alcohol.

RESULTS

Sex was the primary source of heterogeneity in symptom networks. Additional heterogeneity was explained by interpersonal trauma (childhood abuse and domestic violence) in women and domestic violence, cannabis use, ethnicity in men. Among women, especially those exposed to early interpersonal trauma, an affective loading within psychosis may have distinct relevance. Men, particularly those from minority ethnic groups, demonstrated a strong network connection between hallucinatory experiences and persecutory ideation.

CONCLUSION

Symptom networks of psychosis expression in the general population are highly heterogeneous. The structure of symptom networks seems to reflect distinct sex-related adversities, etiologies, and mechanisms of symptom-expression. Disentangling the complex interplay of sex, minority ethnic group status, and other risk factors may help optimize early intervention and prevention strategies in psychosis.

The role of identity in the development of depressive, anxiety, and psychosis symptoms in adolescents exposed to childhood adversity

INTRODUCTION

Childhood adversity is a major risk factor for psychiatric disorders and has especially been associated with an admixture of depressive, anxiety, and psychosis symptoms. Identity formation, a main developmental task during adolescence, may be impacted by these adverse experiences and act as an important process in the association between childhood adversity and psychopathology.

METHODS

We investigated the association between childhood adversity, identity formation, and depressive, anxiety, and psychosis symptoms cross-sectionally in 1913 Flemish adolescents between 11 and 20 years old (mean = 13.76, SD = 1.86). Adolescents completed questionnaires during the first wave of the SIGMA study between January 2018 and May 2019.

RESULTS

Childhood interpersonal adversity was associated with increased identity confusion and decreased identity synthesis. Additionally, identity confusion was associated with increased self-reported levels of psychopathology and potentially mediated the association between childhood adversity and psychopathology.

CONCLUSION

This study highlights the importance of promoting healthy identity formation in adolescents with and without exposure to adverse childhood experiences.

Low levels of Methyl-CpG binding protein 2 are accompanied by an increased vulnerability to the negative outcomes of stress exposure during childhood in healthy women

Numerous mental illnesses arise following stressful events in vulnerable individuals, with females being generally more affected than males. Adverse childhood experiences are known to increase the risk of developing psychopathologies and DNA methylation was demonstrated to drive the long-lasting effects of early life stress and promote stress susceptibility. Methyl-CpG binding protein 2 (MECP2), an X-linked reader of the DNA methylome, is altered in many mental disorders of stress origin, suggesting MECP2 as a marker of stress susceptibility; previous works also suggest a link between MECP2 and early stress experiences. The present work explored whether a reduced expression of MECP2 is paralleled by an increased vulnerability to the negative outcomes of stress exposure during childhood. To this aim, blood MECP2 mRNA levels were analyzed in 63 people without history of mental disorders and traits pertaining to depressive and anxiety symptom clusters were assessed as proxies of the vulnerability to develop stress-related disorders; stress exposure during childhood was also evaluated. Using structural equation modeling, we demonstrate that reduced MECP2 expression is accompanied by symptoms of anxiety/depression in association with exposure to stress in early life, selectively in healthy women. These results suggest a gender-specific involvement of MECP2 in the maladaptive outcomes of childhood adversities, and shed new light on the complex biology underlying gender bias in stress susceptibility.

A systematic review and meta-analysis of the association between emotional stress reactivity and psychosis

AIM

Emotional stress reactivity may be a mediating factor in the association between trauma and psychosis. This review aimed to (i) identify, summarise and critically evaluate the link between emotional stress reactivity and psychotic experiences (ii) examine evidence for a 'dose-response' relationship between stress reactivity and psychosis in the wider psychosis phenotype (i.e., sub-clinical symptoms).

METHODS

Electronic database searches (PsychINFO, MEDLINE, EMBASE) were conducted for studies which investigated the link between stress reactivity and psychosis, psychotic symptoms, or a vulnerability to developing psychosis (wider phenotype). Cross-sectional, experimental and experience sampling method study designs were eligible for inclusion.

RESULTS

Fourty five eligible articles were identified (N participants = 8830). Narrative synthesis showed that increased emotional stress reactivity was associated with psychosis and subclinical psychotic experiences across all study designs, however, findings were inconsistent across studies. The preliminary meta-analysis (k = 4, n = 383) showed increases in emotional stress reactivity was associated with higher negative affect in response to event-related stress, in those with psychosis compared to controls (mean difference in beta coefficients = 0.05, 95% CI 0.02-0.08, p = .004). However, this difference was small with a considerable degree of heterogeneity (p = .001, I²  = 81%) so results should be interpreted with caution.

CONCLUSIONS

Overall, the evidence suggests that there is a link between emotional stress reactivity and psychosis in those with psychosis, those at high risk of developing psychosis and in relation to subclinical psychotic-like experiences in the general population.

The Impact of Life Trauma on Mental Health and Suicidal Behavior: A Study from Portuguese Language Countries

Several studies report the incidence of traumatic experiences in community and clinical samples, and substantial research demonstrates the impact of traumatic events on mental health and suicidal behavior, but this area remains unexplored in the Community of Portuguese Language Countries (CPLC). Thus, this study aims to (1) describe traumatic experiences, mental health levels and suicidal behavior among individuals from Portugal, Brazil and African Countries with Portuguese as an Official Language (ACPOL); (2) assess correlations between traumatic experiences and mental health and suicidal behavior; and (3) assess the impact of exposure to a traumatic event on mental health and suicidal behavior. The measurement instruments included a sociodemographic questionnaire, Brief Trauma Questionnaire, Brief Symptoms Inventory-18, and the Portuguese version of the Suicidal Behaviors Questionnaire-Revised. ACPOL participants reported greater impact of war, Portuguese participants reported greater impact of disasters, and Brazilian participants reported greater impact of psychological and sexual abuse, assault, and death of a family member. Brazilian participants showed the worst levels of mental health and suicidal thoughts. Strong correlations were found between traumatic experiences and mental health levels and suicidal behavior. Traumatic experiences contributed to the explanation of mental health levels and probability of committing suicide.

Spatial attention impairments are characterized by specific electro-encephalographic correlates and partially mediate the association between early life stress and anxiety

Although impaired attention is a diagnostic feature of anxiety disorders, we lack an understanding of which aspects of attention are impaired, the neurobiological basis of these impairments, and the contribution of stressors. To address these gaps in knowledge, we developed and tested behavioral tasks designed to parse the subdomains of attention impairments associated with anxiety symptoms and used electro-encephalographic (EEG) recordings to probe the neural basis of attentional performance. Participants were n = 55 individuals aged 18-35 with mild-to-moderate mood and anxiety symptoms. We also assessed stressful life events that may impact mental health and attention abilities, including stressors that occurred in early life before age 18 years. Severity of anxiety was found to be specifically associated with impairments in spatial attention but not feature-based attention. These impairments in spatial attention also partially mediated the association between early-life stressors and anxiety symptoms. Impairments in spatial selective attention were associated with decreased posterior alpha oscillations in EEG recordings in a subsample of participants, whereas spatial divided attention impairments were associated with decreased frontocentral theta oscillations. Our results provide a thorough characterization of attention impairments associated with anxiety, their EEG correlates, and the impact of stressors both in early life and adulthood.

Psychological resilience and daily stress mediate the effect of childhood trauma on depression

OBJECTIVE

Childhood trauma (CT) is a well-recognized distal risk factor for depression. Previous studies suggested that the psychological mechanism of the impact of childhood trauma on depression may be attributed to some mediators such as daily stress and psychological resilience. This study aimed to assess how daily stress and resilience affect the relationship between childhood trauma and depression in adult clinical context.

METHOD

In this cross-section survey, a total of 569 clinical patients with psychological disorders completed a series of psychological scales such as the Childhood Trauma Questionnaire (CTQ), the Center for Epidemiologic Studies Depression Scale (CESD), the Perceived Stress Scale (PSS) and Connor-Davidson Resilience Scale (CD-RISC). To show the relationship among childhood trauma, psychological resilience, daily stress and depression, structural equation modeling (SEM) was performed.

RESULTS

The results indicated that psychological resilience and daily stress partially mediated the relationship between childhood trauma and depressive symptoms. Childhood trauma not only exerted direct effect on depressive symptoms, but also had indirect effect through the mediation pathway (resilience → daily stress) on depressive symptoms. The chain mediation pathway through resilience and daily stress was weighted 43.31%.

CONCLUSIONS

The study provides novel evidence on the underlying process between childhood trauma and depression. The distal factor childhood trauma can influence the latter depression by the chain effect of psychological resilience and daily stress. Therefore, some clinical interventions to improve psychological resilience to carry off daily stress are the way to reduce the impact of childhood trauma on depression.

Anxiety and Insomnia Among Urban Slum Dwellers in Bangladesh: The Role of COVID-19 and Its Associated Factors

Background: Although mental health is an important part of health and wellbeing, very little is known about the impact of the COVID-19 pandemic on the mental health of marginalized communities like urban slum dwellers. Our study estimated the prevalence of generalized anxiety disorder and insomnia among the residents of the informal settlements of Dhaka, Bangladesh, during the COVID-19 pandemic. Methods: A cross-sectional phone-based survey was conducted from October to November 2020 among adult residents of five informal settlements of Dhaka city randomly chosen from an existing Urban Health and Demographic Surveillance Systems (UHDSS) run by icddr,b. Data on Generalized Anxiety Disorder-7 (GAD-7) and Insomnia Severity Index (ISI) were collected. A multinomial logistic regression was performed to assess the associated factors of anxiety and insomnia. Results: Of the total 586 participants, the prevalence of mild to severe anxiety and insomnia were 53% and 43%, respectively. As per the multinomial regression analysis, participants with mild anxiety were significantly more likely to be older (>50 years) and afraid of COVID-19 infection. Likewise, participants with moderate/severe anxiety were significantly more likely to share less household facilities (e.g., toilet, kitchen, water) (OR: 2.23; 95% CI: 1.31-3.79), to have difficulties in food availability (OR: 2.76; 95% CI: 1.10-6.93), to be afraid of self (OR: 5.27; 95% CI: 2.82-9.88), and to worry about the family members (OR: 2.26; 95% CI: 1.23-4.17) getting infected. Participants with mild insomnia were significantly more likely to share fewer household facilities and be afraid of being infected with COVID-19 infection. Moreover, participants with moderate/severe insomnia were significantly more likely to be female (OR: 1.90; 95% CI: 1.02-3.56), to receive food aid (OR: 0.50; 95% CI: 0.29-0.88), to be afraid of self (OR: 3.85; 95% CI: 1.81-8.19), and to worry about someone like friends or neighbors (OR: 2.45; 95% CI: 1.07-5.58) getting infected with COVID-19. Conclusions: We found elevated prevalence of both anxiety and insomnia among the urban poor of Bangladesh in the context of COVID-19. This indicates the importance of integrating mental health in the mitigation and recovery efforts related to similar crises for the urban poor in the future.

Do positive and negative emotional reactions during war predict subsequent symptomatology? A prospective experience sampling study

While peritraumatic negative emotions have been associated with subsequent posttraumatic stress and depression, the predictive role of real-time emotional reactions to specific stressors during prolonged stress exposure is still unclear, particularly that of positive emotions. The current study uses experience sampling methodology to examine individual general levels of negative and positive emotions, and emotional reactivity to specific stressors during war, as prospective predictors of posttraumatic stress and depression. Ninety-six civilians exposed to rocket fire during the 2014 Israel-Gaza war reported exposure to rocket warning sirens and levels of ten negative and six positive emotions twice a day for 30 days. Symptoms of posttraumatic stress and depression were then assessed two months post-war. Participants reported higher negative emotions and lower positive emotions during assessment windows with sirens. Over time, negative emotions decreased and positive emotions increased. Higher levels of overall negative emotions predicted posttraumatic stress symptoms and depression symptoms two months later. Levels of positive emotions, and negative and positive emotional reactivity to sirens, were not associated with subsequent symptomatology. Our results indicate the stronger role of overall negative emotions as predictors of symptomatology compared with momentary emotional reactivity, and the stronger predictive role of negative compared with positive emotions.

The association between self-reported stress and cardiovascular measures in daily life: A systematic review

BACKGROUND

Stress plays an important role in the development of mental illness, and an increasing number of studies is trying to detect moments of perceived stress in everyday life based on physiological data gathered using ambulatory devices. However, based on laboratory studies, there is only modest evidence for a relationship between self-reported stress and physiological ambulatory measures. This descriptive systematic review evaluates the evidence for studies investigating an association between self-reported stress and physiological measures under daily life conditions.

METHODS

Three databases were searched for articles assessing an association between self-reported stress and cardiovascular and skin conductance measures simultaneously over the course of at least a day.

RESULTS

We reviewed findings of 36 studies investigating an association between self-reported stress and cardiovascular measures with overall 135 analyses of associations between self-reported stress and cardiovascular measures. Overall, 35% of all analyses showed a significant or marginally significant association in the expected direction. The most consistent results were found for perceived stress, high-arousal negative affect scales, and event-related self-reported stress measures, and for frequency-domain heart rate variability physiological measures. There was much heterogeneity in measures and methods.

CONCLUSION

These findings confirm that daily-life stress-dynamics are complex and require a better understanding. Choices in design and measurement seem to play a role. We provide some guidance for future studies.

Relationships between childhood trauma and perceived stress in the general population: a network perspective

BACKGROUND

Experiences of childhood trauma (CT) are associated with increased psychological vulnerability. Past research suggests that CT might alter stress processing with a subsequent negative impact on mental health. However, it is currently unclear how different domains of CT exert effects on specific subjective experiences of stress during adulthood.

METHODS

In the present study, we used network analysis to explore the complex interplay between distinct domains of CT and perceived stress in a large, general-population sample of middle-aged adults (N = 1252). We used a data-driven community-detection algorithm to identify strongly connected subgroups of items within the network. To assess the replicability of the findings, we repeated the analyses in a second sample (N = 862). Combining data from both samples, we evaluated network differences between men (n = 955) and women (n = 1159).

RESULTS

Results indicate specific associations between distinct domains of CT and perceived stress. CT domains reflecting a dimension of deprivation, i.e. experiences of neglect, were associated exclusively to a stress network community representing low perceived self-efficacy. By contrast, CT associated with threat, i.e. experiences of abuse, was specifically related to a stress community reflecting perceived helplessness. Our results replicated with high accordance in the second sample. We found no difference in network structure between men and women, but overall a stronger connected network in women.

CONCLUSIONS

Our findings emphasize the unique role of distinct domains of CT in psychological stress processes in adulthood, implying opportunities for targeted interventions following distinct domains of CT.

Burden of depression and predictors among Ethiopian stroke survivors: Cross-sectional study

BACKGROUND

stroke is a common cause of mortality and morbidity in low- and middle-income countries. It is a very sudden episode in the patients' lives and can lead to multiple psychosocial, social, and economic consequences, and psychiatric problems. poststroke depression is the most common and major neuropsychiatric consequence of stroke that affects one-third of stroke survivors. The aim of this study to assess the burden of depression and its predictors among stroke survivors with local version validated Patient Health Questionnaire.

METHODS

An institutional-based cross-sectional study was conducted among stroke patients at selected tertiary level hospitals. Data were collected by interview method using structured questionnaires, and patient medical record reviews and data were recruited by using consecutive sampling method. Bivariate and multivariable binary logistic regression model analysis was used with SPSS version 23 to identify factors associated with depression.

RESULTS

A total of one hundred eighty stroke patients participated in the study with a response rate of 88.2%. The overall prevalence of depression is 49.6% (95% CI: 42.8, 56.7). Occupation, marital status, level of education of stroke patients was significantly associated with post stroke depression with P < 0.05.

CONCLUSION

The study findings presented that nearly half of the stroke patients suffered from post stroke depression. Post-stroke depression was strongly associated with patient occupation, marital status, and level of education There is urgent need for integration of screening for and management of post-stroke depression among stroke survivors.

Clinical Outcomes of Severe Forms of Early Social Stress

Early social stress, particularly severe but nevertheless frequent forms such as abuse and neglect, are among the major risk factors for the development of mental disorders. However, we only have very limited knowledge of the psychobiological disease mechanisms underlying the influence of early life stress and stress-related disorders during this vulnerable phase of life. Early stress can have long-lasting adverse effects on the brain and other somatic systems, e.g. through influences on brain development. In adulthood, the prior experience of abuse or neglect can result in complex clinical profiles. Besides conditions such as mood and anxiety disorders as well as posttraumatic stress disorder, substance use disorders (SUD) are among the most prevalent sequelae of early social stress. Current social stress further influences the development and maintenance of these disorders, e.g., by increasing the risk of relapses. In this chapter, we will first give an overview of currently used methods to assess the phenomenology and pathophysiology of stress-related disorders and then focus on the phenomenological and neurobiological background of the interaction between early social stress and SUD. We will give an overview of important insights from neuroimaging studies and will also highlight recent findings from studies using digital tools such as ecological momentary assessment or virtual reality to capture the influence of early social stress as well as current social stress in everyday life of persons with SUD.

A longitudinal study of childhood trauma impacting on negative emotional symptoms among college students: a moderated mediation analysis

The present study investigated the possible mediation of resilience in the relationship between childhood trauma and negative emotional symptoms (depression, anxiety, and stress) and whether this mediation depends on the levels of trait mindfulness. A total of 629 college students (female: 189, 30.0%; age: M= 18.43, SD = .90) completed the childhood trauma questionnaire (CTQ), the Connor-Davidson resilience scale (CD-RISC), and the mindful attention awareness scale (MAAS) at baseline assessment (T1), and completed the depression anxiety stress scale (DASS) three months later (T2). After controlling for age and gender, the moderated mediation analysis with longitudinal data suggested that resilience mediated the link between childhood trauma and negative emotional symptoms, and the indirect effect of childhood trauma on negative emotional symptoms was moderated by trait mindfulness. Specifically, the indirect effect was weaker among individuals with a high level of mindfulness compared to those with a low level of mindfulness. The findings suggested that trait mindfulness significantly influenced the indirect effect of childhood trauma on negative emotional symptoms via resilience. However, when the model was analyzed for males and females, respectively, the results suggested that the moderated mediating effects were only found for males, but not for females.

Structural equation modeling approach to explore the influence of childhood maltreatment in adults

Background

Childhood maltreatment affects social functioning in the general adult population. However, how child abuse affects functional disability in adulthood remains unknown. Thus, we investigated the correlation between child abuse, depressive symptoms, cognitive complaints, and functional disability in adult community volunteers.

Methods

Participants (N = 556) completed the Child Abuse and Trauma Scale, Patient Health Questionnaire-9, Cognitive Complaints in Bipolar Disorder Rating Assessment, and Sheehan Disability Scale. Multiple regression analyses and structural equation modeling were performed to evaluate scale correlations.

Results

Structural equation modeling showed that the direct effect of childhood maltreatment on depressive symptoms, the indirect effect of childhood maltreatment on cognitive function via depressive symptoms, and the indirect effects of childhood maltreatment on functional disability via depressive symptoms and via cognitive function were all significant. The direct effects of childhood maltreatment on cognitive function and functional disability were not significant. There was no significant association between variables.

Limitations

Cross-sectional designs cannot identify causal relationships between parameters. Participants were adult volunteers from the community; therefore, results may not be generalizable to individuals with psychiatric disorders. Sociodemographic variability was a limitation because we used self-reported childhood maltreatment.

Conclusions

Childhood maltreatment indirectly affects functional disability via depressive symptoms and via cognitive function through depressive symptoms. We suggest that depressive symptoms and cognitive function play crucial roles in the influence of childhood maltreatment on functional disability in adult community volunteers.

Stress perception following childhood adversity: Unique associations with adversity type and sex

Childhood adversity is associated with poor mental and physical health outcomes across the life span. Alterations in the hypothalamic-pituitary-adrenal axis are considered a key mechanism underlying these associations, although findings have been mixed. These inconsistencies suggest that other aspects of stress processing may underlie variations in this these associations, and that differences in adversity type, sex, and age may be relevant. The current study investigated the relationship between childhood adversity, stress perception, and morning cortisol, and examined whether differences in adversity type (generalized vs. threat and deprivation), sex, and age had distinct effects on these associations. Salivary cortisol samples, daily hassle stress ratings, and retrospective measures of childhood adversity were collected from a large sample of youth at risk for serious mental illness including psychoses (n = 605, mean age = 19.3). Results indicated that childhood adversity was associated with increased stress perception, which subsequently predicted higher morning cortisol levels; however, these associations were specific to threat exposures in females. These findings highlight the role of stress perception in stress vulnerability following childhood adversity and highlight potential sex differences in the impact of threat exposures.

Pituitary dysmaturation affects psychopathology and neurodevelopment in 22q11.2 Deletion Syndrome

BACKGROUND

22q11.2 Deletion Syndrome (22q11DS) confers strongly increased genetic risk for multiple psychiatric disorders. Similarly to the general population, rates of psychiatric comorbidity suggest that common disease mechanisms are shared across dimensions of psychopathology. Such pleiotropic disease mechanisms remain however currently unknown. We hypothesized that pituitary dysmaturation, indicative of HPA-axis dysregulation, could correlate to reduced tolerance to daily life stressors and reflect pleiotropic risk factor for psychopathology. Moreover HPA-axis dysregulation could affect atypical cortical and hippocampal development previously described in 22q11DS.

METHODS

Pituitary volume, hippocampal volume and cortical thickness measures were obtained from T1-weighted MRI images in a large longitudinal cohort of youth with 22q11DS (115 subjects, 260 scans, age-range = 5.4-31.6) and healthy controls (151 subjects, 280 scans, age-range = 5.1-32.3). We explored effects of pituitary dysmaturation on tolerance to stress, psychopathology and neurodevelopment employing mixed-models linear regression. Associations of pituitary and cortical development were correlated with the expression pattern of glucocorticoid receptor gene NR3C1 obtained from the Allen-Human-Brain-Atlas.

RESULTS

We observed aberrant pituitary developmental trajectories in 22q11DS, with volumetric reductions emerging by young-adulthood (P = 0.0006). Longitudinal pituitary decline was associated with to reduced tolerance to stress (P = 0.04), higher overall psychopathology (P = 0.0003) and increased risk of psychiatric comorbidity (P = 0.02). Moreover, pituitary decline correlated with blunted growth of the right hippocampus (P = 0.03) and to increased cortical thinning of mostly temporal and orbitofrontal regions mediated by NR3C1 gene expression.

CONCLUSION

Atypical pituitary development could reflect progressive extinction of HPAA due to chronic hyper-activation, in agreement with existing biochemical evidence in 22q11DS. HPAA dysregulation could represent and endophenotype that confers pleiotropic vulnerability to psychopathology and atypical neurodevelopment in 22q11DS.

Stressful experiences affect the course of co-occurring obsessive-compulsive and psychotic symptoms: A focus on within-subject processes

OBJECTIVE

Obsessive-compulsive symptoms (OCS) frequently occur in patients with psychotic disorders and are associated with higher burden and poorer prognosis. This study prospectively investigated the effect of stressful experiences on the severity of OCS and co-occurring psychotic and affective symptoms, with a focus on within-subject processes.

METHOD

Monthly assessments over 6 months in patients with a psychotic disorder (n = 56) and unaffected siblings (n = 49) resulted in 309 and 277 observations, respectively. Linear mixed-effects models investigated the disaggregated effects of within-subject changes and between-subject differences in stressful events on OCS, positive, negative and depressive symptoms. Subsequently, moderating effects of coping strategies and dysfunctional metacognitive beliefs were assessed. Mediation analyses investigated direct and indirect effects of stressful events on OCS four weeks later.

RESULTS

Stressful experiences were associated with severity in almost all symptom domains on the between- and within-subject levels. Dysfunctional coping and metacognitive beliefs moderated these associations. Patients and siblings with a tendency for passive coping showed higher within-subject increase in depressive symptoms, whereas passive coping and dysfunctional beliefs moderated the association between stressful experiences and severity of positive symptoms and OCS on the between-subject level. Effects of stressful experiences on OCS four weeks later were partially mediated by depressive and positive symptoms in patients and siblings.

CONCLUSIONS

Findings suggest that severity and variability of co-occurring psychopathology can partly be explained by recent stressful events and the way individuals cope with these experiences. The implementation of coping-oriented interventions could possibly help to prevent development and/or aggravation of co-occurring symptom severity.

The impact of childhood trauma on psychosocial functioning and physical health in a non-clinical community sample of young adults

OBJECTIVE

Given the fundamental emotional, social and physical development that occurs during the early years of life, childhood experiences are formative in shaping a person's life trajectory. Childhood trauma is a prevalent, multifaceted issue with well-documented long-term adverse health effects in clinical populations however; the impact of childhood trauma in the community is less clear. To address this, this study investigated how childhood trauma may impact physical and psychological health, sleep quality and autonomic function in a non-clinical community sample of adults.

METHOD

Participants completed questionnaires, an in-laboratory autonomic assessment (including stress reactivity to mental and physical stressors) and overnight autonomic and sleep monitoring. Overall childhood trauma and its subtypes (e.g. physical abuse, emotional neglect) were defined using the Childhood Trauma Questionnaire.

RESULTS

We identified 22 childhood trauma cases (total score > 36) and, of the 89 non-childhood trauma cases, some individuals also experienced significant levels of trauma in one or more of the childhood trauma subtypes. Childhood trauma and some trauma subtypes were significantly correlated with a myriad of negative physiological and physical health outcomes including elevated psychological distress, increased sleep disturbances, reduced emotional wellbeing and lower perceived social support. Autonomic dysregulation was found in those with high levels of childhood trauma, which was reflected in an increased stress response to laboratory tasks. Notably, the experience of physical abuse in childhood was significantly associated with alterations in nocturnal heart rate and heart rate variability.

CONCLUSION

Together, these results highlight that childhood trauma can have lasting detrimental consequences on an individual's emotional and physical health, sleep quality and stress reactivity.

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.

Neurobehavioural mechanisms of threat generalization moderate the link between childhood maltreatment and psychopathology in emerging adulthood

BACKGROUND

Childhood maltreatment is a transdiagnostic risk factor for later psychopathology and has been associated with altered brain circuitry involved in the processing of threat and safety. Examining threat generalization mechanisms in young adults with childhood maltreatment and psychiatric symptoms may elucidate a pathway linking early-life adversities to the presence of subclinical psychopathology.

METHODS

We recruited youth aged 16–25 years with subclinical psychiatric symptomatology and healthy controls. They were dichotomized into 2 groups: 1 with a high level of childhood maltreatment (n = 58) and 1 with no or a low level of childhood maltreatment (n = 55). Participants underwent a functional MRI threat generalization paradigm, measuring self-reported fear, expectancy of an unconditioned stimulus (US) and neural responses.

RESULTS

We observed interactions between childhood maltreatment and threat generalization indices on subclinical symptom load. In individuals reporting high levels of childhood maltreatment, enhanced generalization in self-reported fear and US expectancy was related to higher levels of psychopathology. Imaging results revealed that in the group with high levels of childhood maltreatment, lower activation in the left hippocampus during threat generalization was associated with a higher symptom load. Associations between threat generalization and psychopathology were nonsignificant overall in the group with no or low levels of childhood maltreatment.

LIMITATIONS

The data were acquired in a cross-sectional manner, precluding definitive insight into the causality of childhood maltreatment, threat generalization and psychopathology.

CONCLUSION

Our results suggest that threat generalization mechanisms may moderate the link between childhood maltreatment and subclinical psychopathology during emerging adulthood. Threat generalization could represent a vulnerability factor for developing later psychopathology in individuals being exposed to childhood maltreatment.

Mediating role of aberrant salience and self-disturbances for the relationship between childhood trauma and psychotic-like experiences in the general population

INTRODUCTION

The relationship between childhood trauma and the risk of psychosis is well established. However, the mechanisms of the relationship are still unknown. We investigated whether two factors involved in the risk of psychosis - self-disturbances and aberrant salience - mediate the relationship between childhood trauma and psychotic-like experiences in the general population.

METHODS

We tested parallel mediation models which assume that the relationship between childhood trauma (Childhood Trauma Questionnaire, the CTQ) and psychotic-like experiences (Prodromal questionnaire, PQ-16) is mediated by both self-disturbances and aberrant salience (Aberrant Salience Inventory, the ASI) in a general population sample (N = 649). Separate parallel mediation models were calculated for cumulative childhood trauma, exposure to abusive behaviors (emotional, physical and sexual abuse) and neglect (emotional and physical neglect) controlling for gender.

RESULTS

Childhood traumatic life events predicted psychotic-like experiences. Childhood trauma was also related to self-disturbances and aberrant salience. Self-disturbances and aberrant salience were related to psychotic-like experiences. Models of mediation for the relationship between cumulative childhood trauma and neglect and psychotic-like experiences revealed an indirect-only mediation by self-disturbances and aberrant salience. The model for childhood abuse suggested a complementary mediation and was affected by gender.

CONCLUSIONS

Our results provide tentative evidence that self-disturbances and aberrant salience are important factors in the translation of childhood trauma into the risk of psychosis in the general population. Causal relationships could not be inferred from this cross-sectional data. Hence, longitudinal studies on a clinical sample are warranted.

Evidence that the association of childhood trauma with psychosis and related psychopathology is not explained by gene-environment correlation: A monozygotic twin differences approach

BACKGROUND

Converging evidence supports childhood trauma as possible causal risk for psychosis and related psychopathology. However, studies have shown that baseline psychotic symptoms may actually increase risk for subsequent victimization, suggesting that exposure to CT is not random but may result from pre-existing vulnerability. Therefore, studies testing whether the association between CT and psychopathology persists when accounting for gene-environment correlation are much needed.

METHODS

A monozygotic (MZ) twin differences approach was used to examine whether differences in CT exposure among MZ twin pairs would be associated with MZ differences in symptoms. As MZ twins are genetically identical, within-pair correlations between CT exposure and psychopathology rule out the possibility that the association is solely attributable to gene-environment correlation. 266 monozygotic twins (133 pairs) from a larger general population study were available for analysis.

RESULTS

CT was associated with symptoms of psychosis (B = 0.62; SE = 0.08, p < .001) and overall psychopathology (B = 43.13; SE = 6.27; p < .001). There were measurable differences within pairs in CT exposure and symptoms, allowing for meaningful within-pair differences. Within-pair differences in CT exposure were associated with within-pair differences in symptoms of psychosis (B = 0.35; SE = 0.16; p = .024), as well as with overall psychopathology (B = 29.22; SE = 12.24; p = .018), anxiety (B = 0.65; SE = 0.21; p = .002) and depression (B = 0.37; SE = 0.18; p = .043).

CONCLUSION

While it is not unlikely that pre-existing vulnerability may increase the risk for traumatic exposures, such gene-environment correlation does not explain away the association between CT and psychopathology. The present findings thus suggest that at least part of the association between CT and psychopathology may be causal.

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.

Experience sampling methodology in mental health research: new insights and technical developments

In the mental health field, there is a growing awareness that the study of psychiatric symptoms in the context of everyday life, using experience sampling methodology (ESM), may provide a powerful and necessary addition to more conventional research approaches. ESM, a structured self-report diary technique, allows the investigation of experiences within, and in interaction with, the real-world context. This paper provides an overview of how zooming in on the micro-level of experience and behaviour using ESM adds new insights and additional perspectives to standard approaches. More specifically, it discusses how ESM: a) contributes to a deeper understanding of psychopathological phenomena, b) allows to capture variability over time, c) aids in identifying internal and situational determinants of variability in symptomatology, and d) enables a thorough investigation of the interaction between the person and his/her environment and of real-life social interactions. Next to improving assessment of psychopathology and its underlying mechanisms, ESM contributes to advancing and changing clinical practice by allowing a more fine-grained evaluation of treatment effects as well as by providing the opportunity for extending treatment beyond the clinical setting into real life with the development of ecological momentary interventions. Furthermore, this paper provides an overview of the technical details of setting up an ESM study in terms of design, questionnaire development and statistical approaches. Overall, although a number of considerations and challenges remain, ESM offers one of the best opportunities for personalized medicine in psychiatry, from both a research and a clinical perspective.

Evidence for altered brain reactivity to norepinephrine in Veterans with a history of traumatic stress

Background

Increases in the quantity or impact of noradrenergic signaling have been implicated in the pathophysiology of posttraumatic stress disorder (PTSD). This increased signaling may result from increased norepinephrine (NE) release, from altered brain responses to NE, or from a combination of both factors. Here, we tested the hypothesis that Veterans reporting a history of trauma exposure would show an increased association between brain NE and mental health symptoms commonly observed after trauma, as compared to Veterans who did not report a history of trauma exposure, consistent with the possibility of increased brain reactivity to NE after traumatic stress.

Methods

Using a convenience sample of 69 male Veterans with a history of combat-theater deployment, we examined the relationship between trauma-related mental health symptoms and the concentration of NE in cerebrospinal fluid (CSF). CSF NE levels were measured by HPLC in CSF from morning lumbar puncture. Behavioral symptoms associated with diagnoses of PTSD, depression, insomnia, or post-concussive syndrome (PCS), which together cover a wide variety of symptoms associated with alterations in arousal systems, such as sleep, mood, concentration, and anxiety, were assessed via self-report (PTSD Checklist [PCL] for PTSD, Patient Health Questionnaire 9 [PHQ9] for depression, Pittsburgh Sleep Quality Index [PSQI] for sleep problems including insomnia, and Neurobehavioral Symptom Inventory [NSI] for PCS) and structured clinical interview (Clinician-Administered PSTD Scale [CAPS]). Individuals meeting criterion A of the DSM-IV diagnostic criteria for PTSD were considered trauma-exposed. Linear regression models were used to quantify the association between CSF NE and symptom intensity in participants with and without a history of trauma exposure, as well as in participants with a history of trauma exposure who were currently taking the noradrenergic receptor antagonist prazosin.

Results

Fifty-two Veterans met criteria for a history of trauma exposure; of these, 36 met criteria for PTSD. CSF NE levels were not significantly different in Veterans with a history of trauma compared to those without, nor in Veterans with PTSD as compared to those without. Veterans with a history of trauma and who were not using the medication prazosin demonstrated a significantly more positive correlation between CSF NE and behavioral symptom expression than Veterans who had not experienced traumatic stress. No relationship between CSF NE and behavioral symptom expression was found in Veterans who had experienced traumatic stress and were taking prazosin at the time of the assessments.

Conclusions

These results are consistent with increased central nervous system responsiveness to noradrenergic signaling in individuals with a history of traumatic exposure, raising the possibility that there may be long-lasting physiologic effects of trauma-exposure that exist independently of whether an individual meets criteria for PTSD at any given point in time. Exploration of the mechanism by which brain responsiveness to NE is modulated following trauma holds the possibility of finding new strategies for both preventing and treating PTSD.

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CSF Norepinephrine (NE) and common mental health symptoms were assessed in Veterans.

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In Veterans without trauma exposure, CSF NE was inversely associated with symptoms.

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In those with trauma exposure, CSF NE was more positively associated with symptoms.

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Trauma exposure may alter central reactivity to NE.

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PTSD may occur when there is both increased release of, and reactivity to, NE.