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

Gender differences in the associations between childhood adversity and psychopathology in the general population

PURPOSE

To explore gender differences of the associations between childhood adversity (CA) subtypes and psychiatric symptoms in the general population.

METHODS

Data of 791 participants were retrieved from a general population twin cohort. The Symptom Checklist-90 Revised (SCL-90) and the Childhood Trauma Questionnaire were used to assess overall psychopathology with nine symptom domains scores and total CA with exposure to five CA subtypes, respectively. The associations between CA and psychopathology were analyzed in men and women separately and were subsequently compared.

RESULTS

Total CA was associated with total SCL-90 and all symptom domains without significant gender differences. However, the analyses of CA subtypes showed that the association between emotional abuse and total SCL-90 was stronger in women compared to men [χ2(1) = 4.10, P = 0.043]. Sexual abuse was significantly associated with total SCL-90 in women, but emotional neglect and physical neglect were associated with total SCL-90 in men. Exploratory analyses of CA subtypes and SCL-90 subdomains confirmed the pattern of gender-specific associations. In women, emotional abuse was associated with all symptom domains, and sexual abuse was associated with all except phobic anxiety and interpersonal sensitivity. In men, emotional neglect was associated with depression, and physical neglect was associated with phobic anxiety, anxiety, interpersonal sensitivity, obsessive-compulsive, paranoid ideation, and hostility subdomains.

CONCLUSION

CA is a trans-syndromal risk factor regardless of gender. However, differential associations between CA subtypes and symptom manifestation might exist. Abuse might be particularly associated with psychopathology in women, whereas neglect might be associated with psychopathology in men.

How first-episode psychosis patients' subjective beliefs about their childhood trauma's causal effect provide support for potential schizophrenia subtypes

BACKGROUND

Childhood and adolescent trauma is a risk factor for developing psychosis-spectrum disorders. The current study aimed to assess how childhood trauma might predict psychosis symptomatology, and how patients' beliefs of whether trauma is the cause of psychosis might affect this association.

METHODS

Ninety-six first-episode psychosis patients were assessed for childhood traumatic experiences with the Brief Betrayal Trauma Survey, and for psychosis symptoms with the Positive and Negative Syndrome Scale.

RESULTS

Non-interpersonal trauma predicted higher positive symptoms, whereas more trauma domains experienced predicted lower negative symptoms. Almost half of the participants believed trauma to be related to psychosis, were 12 times more likely to reexperience trauma through psychosis, and had higher excitative and emotional symptoms. Non-interpersonal trauma also predicted higher positive symptoms in this group. Those who did not believe trauma to be the cause of psychosis had higher negative symptoms, and a negative dose-response was found for negative and disorganised symptoms, in which more trauma domains experienced predicted lower scores.

CONCLUSIONS

Results imply two traumagenic pathways to psychosis, one characterised by positive, excitative, and emotional symptoms, and one negative subtype, characterised by negative and disorganised symptoms. Clinical implications for how findings might contribute to better treatments are discussed.

Synergistic effects of childhood adversity and polygenic risk in first-episode psychosis: the EU-GEI study

BACKGROUND

A history of childhood adversity is associated with psychotic disorder, with an increase in risk according to the number of exposures. However, it is not known why only some exposed individuals go on to develop psychosis. One possibility is pre-existing polygenic vulnerability. Here, we investigated, in the largest sample of first-episode psychosis (FEP) cases to date, whether childhood adversity and high polygenic risk scores for schizophrenia (SZ-PRS) combine synergistically to increase the risk of psychosis, over and above the effect of each alone.

METHODS

We assigned a schizophrenia-polygenic risk score (SZ-PRS), calculated from the Psychiatric Genomics Consortium (PGC2), to all participants in a sample of 384 FEP patients and 690 controls from the case-control component of the EU-GEI study. Only participants of European ancestry were included in the study. A history of childhood adversity was collected using the Childhood Trauma Questionnaire (CTQ). Synergistic effects were estimated using the interaction contrast ratio (ICR) [odds ratio (OR)exposure and PRS - ORexposure - ORPRS + 1] with adjustment for potential confounders.

RESULTS

There was some evidence that the combined effect of childhood adversities and polygenic risk was greater than the sum of each alone, as indicated by an ICR greater than zero [i.e. ICR 1.28, 95% confidence interval (CI) -1.29 to 3.85]. Examining subtypes of childhood adversities, the strongest synergetic effect was observed for physical abuse (ICR 6.25, 95% CI -6.25 to 20.88).

CONCLUSIONS

Our findings suggest possible synergistic effects of genetic liability and childhood adversity experiences in the onset of FEP, but larger samples are needed to increase precision of estimates.

Childhood Maltreatment and Mental Health Problems: A Systematic Review and Meta-Analysis of Quasi-Experimental Studies

OBJECTIVE

Childhood maltreatment is associated with mental health problems, but the extent to which this relationship is causal remains unclear. To strengthen causal inference, the authors conducted a systematic review and meta-analysis of quasi-experimental studies examining the relationship between childhood maltreatment and mental health problems.

METHODS

A search of PubMed, PsycINFO, and Embase was conducted for peer-reviewed, English-language articles from database inception until January 1, 2022. Studies were included if they examined the association between childhood maltreatment and mental health problems using a quasi-experimental method (e.g., twin/sibling differences design, children of twins design, adoption design, fixed-effects design, random-intercept cross-lagged panel model, natural experiment, propensity score matching, or inverse probability weighting).

RESULTS

Thirty-four quasi-experimental studies were identified, comprising 54,646 independent participants. Before quasi-experimental adjustment for confounding, childhood maltreatment was moderately associated with mental health problems (Cohen's d=0.56, 95% CI=0.41, 0.71). After quasi-experimental adjustment, a small association between childhood maltreatment and mental health problems remained (Cohen's d=0.31, 95% CI=0.24, 0.37). This adjusted association between childhood maltreatment and mental health was consistent across different quasi-experimental methods, and generalized across different psychiatric disorders.

CONCLUSIONS

These findings are consistent with a small, causal contribution of childhood maltreatment to mental health problems. Furthermore, the findings suggest that part of the overall risk of mental health problems in individuals exposed to maltreatment is due to wider genetic and environmental risk factors. Therefore, preventing childhood maltreatment and addressing wider psychiatric risk factors in individuals exposed to maltreatment could help to prevent psychopathology.

A genetically informed Registered Report on adverse childhood experiences and mental health

Children who experience adversities have an elevated risk of mental health problems. However, the extent to which adverse childhood experiences (ACEs) cause mental health problems remains unclear, as previous associations may partly reflect genetic confounding. In this Registered Report, we used DNA from 11,407 children from the United Kingdom and the United States to investigate gene-environment correlations and genetic confounding of the associations between ACEs and mental health. Regarding gene-environment correlations, children with higher polygenic scores for mental health problems had a small increase in odds of ACEs. Regarding genetic confounding, elevated risk of mental health problems in children exposed to ACEs was at least partially due to pre-existing genetic risk. However, some ACEs (such as childhood maltreatment and parental mental illness) remained associated with mental health problems independent of genetic confounding. These findings suggest that interventions addressing heritable psychiatric vulnerabilities in children exposed to ACEs may help reduce their risk of mental health problems.

Prevalence, service use and clinical correlates of hallucinations and delusions in an out-patient population from India

BACKGROUND

Despite the persistent public health problem of positive psychotic symptoms, understanding of symptom specific prevalence rates, clinical correlates and service utilisation are sparse.

AIMS

The current study aimed to establish prevalence, clinical and service utilisation correlates of hallucinations and delusions in people accessing outpatient clinics in Tamil Nadu, India.

METHODS

Secondary patient data from outpatient clinics, over a 12-month period, in 2016, was used for analysis (N = 917). Based on the presence of positive psychotic symptoms (PPSx), the sample was divided into four groups for analysis- hallucinations-only (H), delusions-only (D), both hallucinations and delusions (HD) and neither PPSx (N-PPSx).

RESULTS

Findings indicate that the most prevalent PPSx were hallucinations (10.7%) however, barriers to service utilisation and clinical correlates were associated predominantly with the D and the HD group; as was severe work impairment. Yet, this group was most likely to remain with psychiatric services. Lastly, diagnostic challenges were apparent within the sample.

CONCLUSIONS

The study revealed that despite more barriers to service utilisation, persons with PPSx remain in contact with services. Yet prognosis remains only moderate at best, indicating other mediating and underlying factors impeding recovery may be interplaying and, therefore, a need for enhanced biopsychosocial approaches.

Retrospectively assessed childhood trauma experiences are associated with illness severity in mental disorders adjusted for symptom state

Converging evidence suggests that childhood trauma is a causal factor in schizophrenia (SZ) and in bipolar disorders (BD). Here, we investigated whether retrospective reports are associated with severity of illness, independent of current symptom state in a large sample of participants with SZ or BD. We included 1260 individuals (SZ [n = 461], BD [n = 352]), and healthy controls; HC [n = 447]) recruited from the same catchment area. A history of childhood trauma was obtained with the Childhood Trauma Questionnaire (CTQ). Diagnosis and episodes were obtained with the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I). Clinical symptoms (state) were assessed with the Positive and Negative Syndrome scale (PANSS), the Calgary Depression Scale (CDSS). Trait related illness characteristics were assessed with age at illness onset, number of episodes, and lifetime suicide attempts. Patients who reported multiple types of childhood trauma experiences had significantly more severe illness course including an earlier illness onset, more mood episodes, and increased risk of at least one suicide attempt, also after adjusting for current symptom state. Retrospective assessed childhood trauma experiences are associated with illness severity in mental disorders adjusted for symptom state. Our results strengthen the role of childhood trauma in development of psychopathology.

Schizophrenia Polygenic Risk and Experiences of Childhood Adversity: A Systematic Review and Meta-analysis

BACKGROUND AND HYPOTHESIS

Schizophrenia has been robustly associated with multiple genetic and environmental risk factors. Childhood adversity is one of the most widely replicated environmental risk factors for schizophrenia, but it is unclear if schizophrenia genetic risk alleles contribute to this association.

STUDY DESIGN

In this systematic review and meta-analysis, we assessed the evidence for gene-environment correlation (genes influence likelihood of environmental exposure) between schizophrenia polygenic risk score (PRS) and reported childhood adversity. We also assessed the evidence for a gene-environment interaction (genes influence sensitivity to environmental exposure) in relation to the outcome of schizophrenia and/or psychosis. This study was registered on PROSPERO (CRD42020182812). Following PRISMA guidelines, a search for relevant literature was conducted using Cochrane, MEDLINE, PsycINFO, Web of Science, and Scopus databases until February 2022. All studies that examined the association between schizophrenia PRS and childhood adversity were included.

STUDY RESULTS

Seventeen of 650 identified studies met the inclusion criteria and were assessed against the Newcastle-Ottawa Scale for quality. The meta-analysis found evidence for gene-environment correlation between schizophrenia PRS and childhood adversity (r = .02; 95% CI = 0.01, 0.03; P = .001), but the effect was small and therefore likely to explain only a small proportion of the association between childhood adversity and psychosis. The 4 studies that investigated a gene-environment interaction between schizophrenia PRS and childhood adversity in increasing risk of psychosis reported inconsistent results.

CONCLUSIONS

These findings suggest that a gene-environment correlation could explain a small proportion of the relationship between reported childhood adversity and psychosis.

Substance use confounds associations between peer victimization and aggression in adolescence with mental disorders in adulthood: A prospective birth cohort study

INTRODUCTION

Peer victimization and aggression in adolescence are associated with later mental health morbidity. However, studies examining this association have not controlled for adolescent substance use. We aimed to study the associations between peer victimization, peer aggression, and mental disorders in adulthood, adjusting for substance use in adolescence.

METHODS

Participants were from the prospective Northern Finland Birth Cohort 1986. Data were available for 6682 individuals (70.8% of the original sample). Peer victimization and peer aggression were assessed with items from the Achenbach Youth Self Report at ages 15-16 years. Outcomes were nonorganic psychosis, anxiety disorder, mood disorder, substance use disorder, and any mental disorder (a none-vs-any indicator) at age 33 years collected from nationwide health care, insurance, and pension registers. Family structure, alcohol intoxication frequency, daily smoking, illicit drug use, and baseline psychopathology using Youth Self-Report total score, and parental mental disorders were considered as confounding factors.

RESULTS

In multivariable analyses, the association between peer victimization and psychosis (Hazard ratio [HR]: 2.9, 95% confidence interval [CI]: 1.2-6.9, p = .020) and mood disorder (HR: 1.7, 95% CI: 1.2-2.4, p = .012) in females remained significant after adjusting for confounders. Other associations between female and male peer victimization or aggression and the studied outcomes attenuated after adjustments.

CONCLUSIONS

Some associations between peer victimization and aggression and later mental health morbidity are explained by adolescent substance use. For females, substance use does not account for the increased risk of psychosis and mood disorder in those who experience peer victimization.

Childhood trauma in children at familial high risk of schizophrenia or bipolar disorder: A longitudinal study. The Danish High Risk and Resilience Study - VIA 7 and VIA 11

OBJECTIVES

Childhood trauma increases the risk of developing mental illness as does being born to parents with schizophrenia or bipolar disorder. We aimed to compare prevalence of lifetime childhood trauma among 11-year-old children at familial high risk of schizophrenia (FHR-SZ) or bipolar disorder (FHR-BP) compared with population-based controls (PBCs).

DESIGN

The study is a longitudinal, prospective cohort study of children at FHR-SZ, FHR-BP, and PBCs.

METHODS

A cohort of 512 children at FHR-SZ (N = 199), FHR-BP (N = 118), and PBCs (N = 195) were examined at baseline (mean age 7.8, SD 0.2) and 451 children at FHR-SZ (N = 172), FHR-BP (N = 104), and PBCs (N = 175) were examined at four-year follow-up (mean age 11.9, SD 0.2, retention rate 87.3%). Childhood trauma was measured with a semi-structured interview.

RESULTS

Children at FHR-BP had an elevated risk of exposure to any lifetime trauma (age 0-11 years) compared with PBCs (OR 2.082, 95%CI 1.223-3.545, p = .007) measured with binary logistic regression. One-way ANOVA revealed that both FHR-groups had a higher lifetime prevalence of exposure to a greater number of types of trauma compared with PBCs (FHR-SZ: observed mean: 1.53, 95%CI 1.29-1.77; FHR-BP: observed mean: 1.56, 95%CI 1.26-1.85; PBCs: observed mean: 0.99, 95%CI 0.82-1.17; p < .001). Binary logistic regression showed that the lifetime risk of exposure to interpersonal trauma (age 0-11 years) was elevated for both FHR-groups (FHR-SZ: OR 3.773, 95%CI 2.122-6.710, p < .001; FHR-BP: OR 3.602, 95%CI 1.913-6.783, p < .001).

CONCLUSIONS

Children at FHR-SZ and FHR-BP are at increased risk for being exposed to childhood trauma compared with PBCs. This study underscores the need for early detection, support, and prevention of childhood trauma in children at FHR-SZ and FHR-BP.

The Phenomenology and Neurobiology of Visual Distortions and Hallucinations in Schizophrenia: An Update

Schizophrenia is characterized by visual distortions in ~60% of cases, and visual hallucinations (VH) in ~25-50% of cases, depending on the sample. These symptoms have received relatively little attention in the literature, perhaps due to the higher rate of auditory vs. visual hallucinations in psychotic disorders, which is the reverse of what is found in other neuropsychiatric conditions. Given the clinical significance of these perceptual disturbances, our aim is to help address this gap by updating and expanding upon prior reviews. Specifically, we: (1) present findings on the nature and frequency of VH and distortions in schizophrenia; (2) review proposed syndromes of VH in neuro-ophthalmology and neuropsychiatry, and discuss the extent to which these characterize VH in schizophrenia; (3) review potential cortical mechanisms of VH in schizophrenia; (4) review retinal changes that could contribute to VH in schizophrenia; (5) discuss relationships between findings from laboratory measures of visual processing and VH in schizophrenia; and (6) integrate findings across biological and psychological levels to propose an updated model of VH mechanisms, including how their content is determined, and how they may reflect vulnerabilities in the maintenance of a sense of self. In particular, we emphasize the potential role of alterations at multiple points in the visual pathway, including the retina, the roles of multiple neurotransmitters, and the role of a combination of disinhibited default mode network activity and enhanced state-related apical/contextual drive in determining the onset and content of VH. In short, our goal is to cast a fresh light on the under-studied symptoms of VH and visual distortions in schizophrenia for the purposes of informing future work on mechanisms and the development of targeted therapeutic interventions.

Polygenic liability for schizophrenia and childhood adversity influences daily-life emotion dysregulation and psychosis proneness

OBJECTIVE

To test whether polygenic risk score for schizophrenia (PRS-S) interacts with childhood adversity and daily-life stressors to influence momentary mental state domains (negative affect, positive affect, and subtle psychosis expression) and stress-sensitivity measures.

METHODS

The data were retrieved from a general population twin cohort including 593 adolescents and young adults. Childhood adversity was assessed using the Childhood Trauma Questionnaire. Daily-life stressors and momentary mental state domains were measured using ecological momentary assessment. PRS-S was trained on the latest Psychiatric Genetics Consortium schizophrenia meta-analysis. The analyses were conducted using multilevel mixed-effects tobit regression models.

RESULTS

Both childhood adversity and daily-life stressors were associated with increased negative affect, decreased positive affect, and increased subtle psychosis expression, while PRS-S was only associated with increased positive affect. No gene-environment correlation was detected. There is novel evidence for interaction effects between PRS-S and childhood adversity to influence momentary mental states [negative affect (b = 0.07, P = 0.013), positive affect (b = -0.05, P = 0.043), and subtle psychosis expression (b = 0.11, P = 0.007)] and stress-sensitivity measures.

CONCLUSION

Exposure to childhood adversities, particularly in individuals with high PRS-S, is pleiotropically associated with emotion dysregulation and psychosis proneness.

TwinssCan — Gene-Environment Interaction in Psychotic and Depressive Intermediate Phenotypes: Risk and Protective Factors in a General Population Twin Sample

Meta-analyses suggest that clinical psychopathology is preceded by dimensional behavioral and cognitive phenotypes such as psychotic experiences, executive functioning, working memory and affective dysregulation that are determined by the interplay between genetic and nongenetic factors contributing to the severity of psychopathology. The liability to mental ill health can be psychometrically measured using experimental paradigms that assess neurocognitive processes such as salience attribution, sensitivity to social defeat and reward sensitivity. Here, we describe the TwinssCan, a longitudinal general population twin cohort, which comprises 1202 individuals (796 adolescent/young adult twins, 43 siblings and 363 parents) at baseline. The TwinssCan is part of the European Network of National Networks studying Gene-Environment Interactions in Schizophrenia project and recruited from the East Flanders Prospective Twin Survey. The main objective of this project is to understand psychopathology by evaluating the contribution of genetic and nongenetic factors on subclinical expressions of dimensional phenotypes at a young age before the onset of disorder and their association with neurocognitive processes, such as salience attribution, sensitivity to social defeat and reward sensitivity.

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.

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.