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

Gene × environment effects and mediation involving adverse childhood events, mood and anxiety disorders, and substance dependence

Adverse childhood events (ACEs) contribute to the development of mood and anxiety disorders and substance dependence. However, the extent to which these effects are direct or indirect and whether genetic risk moderates them is unclear. We examined associations among ACEs, mood/anxiety disorders and substance dependence in 12,668 individuals (44.9% female, 42.5% African American/Black, 42.1% European American/white). Using latent variables for each phenotype, we modelled direct and indirect associations of ACEs with substance dependence, mediated by mood/anxiety disorders (the forward or 'self-medication' model) and of ACEs with mood/anxiety disorders, mediated by substance dependence (the reverse or 'substance-induced' model). In a subsample, we tested polygenic scores for the substance dependence and mood/anxiety disorder factors as moderators in the mediation models. Although there were significant indirect paths in both directions, mediation by mood/anxiety disorders (the forward model) was greater than that by substance dependence (the reverse model). Greater genetic risk for substance use disorders was associated with a weaker direct association between ACEs and substance dependence in both ancestry groups (reflecting gene × environment interactions) and a weaker indirect association in European-ancestry individuals (reflecting moderated mediation). We found greater evidence that substance dependence reflects self-medication of mood/anxiety disorders than that mood/anxiety disorders are substance induced. Among individuals at higher genetic risk for substance dependence, ACEs were less associated with that outcome. Following exposure to ACEs, multiple pathways appear to underlie the associations between mood/anxiety disorders and substance dependence. Specification of these pathways could inform individually targeted prevention and treatment approaches.

Adverse Childhood Experiences and Adult Mental Health Outcomes

Importance

Exposure to adverse childhood experiences (ACEs) has consistently been associated with multiple negative mental health outcomes extending into adulthood. However, given that ACEs and psychiatric disorders cluster within families, it remains to be comprehensively assessed to what extent familial confounding contributes to associations between ACEs and clinically confirmed adult psychiatric disorders.

Objective

To investigate whether associations between ACEs and adult mental health outcomes remain after adjusting for familial (genetic and environmental) confounding.

Design, Setting, and Participants

This Swedish twin cohort study used a discordant twin pair design based on monozygotic (MZ) and dizygotic (DZ) twins. A total of 25 252 adult twins (aged 18-47 years) from the Swedish Twin Registry born between 1959 and 1998 were followed up from age 19 years until 2016, with a maximum follow-up time of 39 years. Data were analyzed from April 2022 to November 2023.

Exposures

A total of 7 ACEs, including family violence, emotional abuse or neglect, physical neglect, physical abuse, sexual abuse, rape, and hate crime, were assessed with items from the Life Stressor Checklist-Revised in a web-based survey.

Main Outcomes and Measures

Adult (ages >18 years) clinical diagnosis of psychiatric disorders (ie, depressive, anxiety, alcohol or drug misuse, or stress-related disorders) were obtained from the Swedish National Patient Register.

Results

Of 25 252 twins included in the study (15 038 female [59.6%]; mean [SD] age at ACE assessment, 29.9 [8.7] years), 9751 individuals (38.6%) reported exposure to at least 1 ACE. A greater number of ACEs was associated with increased odds of any psychiatric disorder in the full cohort (odds ratio [OR] per additional ACE, 1.52; 95% CI, 1.48-1.57). The association remained but ORs per additional ACE were attenuated in DZ (1.29; 95% CI, 1.14-1.47) and MZ (1.20; 95% CI, 1.02-1.40) twin pairs. Individuals who were exposed to sexual abuse compared with those who were not exposed had increased odds of any clinically confirmed psychiatric disorder in all comparisons: full cohort (OR, 3.09; 95% CI, 2.68-3.56), DZ twin pairs (OR, 2.10; 95% CI, 1.33-3.32), and MZ twin pairs (1.80; 95% CI, 1.04-3.11).

Conclusions and relevance

This study found that associations between ACEs and adult mental health outcomes remained after controlling for shared genetic and environmental factors, which was particularly evident after multiple ACEs or sexual abuse. These findings suggest that targeted interventions may be associated with reduced risks of future psychopathology.

Patterns of Adverse Childhood Experiences and Neurocognitive Development

Importance

Early life adversity is associated with higher risk of many adult health problems, including mental illness, substance abuse, suicide attempt, and chronic diseases. Many previous studies investigated adversities one at a time or investigated the health toll associated with the cumulative number of adversities.

Objective

To examine the co-occurrence of adversities among children and how specific patterns of adversities are associated with neurocognitive development.

Design, Setting, and Participants

This cohort study used data from the Collaborative Perinatal Project (CPP), which enrolled a national sample of women during pregnancy and followed their offspring to ages 7 to 8 years, between 1959 and 1974. The CPP was a community-based study conducted in 12 US medical centers. The CPP sample was ascertained through prenatal clinics and is diverse with respect to race and socioeconomic status. Data analysis was performed from August 2023 to March 2024.

Exposures

A latent class analysis was conducted of 12 adverse childhood experiences that occurred between birth and 7 years to identify common patterns of childhood adversities.

Main Outcomes and Measures

Five neurocognitive tests were used to measure children's visual-motor, sensory-motor, auditory-vocal, intelligence quotient, and academic skills.

Results

The analysis sample included 49 853 offspring (25 226 boys [50.6%]); 24 436 children (49.0%) had low probability of experiencing any adversity, whereas the remaining half were classified into 5 groups reflecting distinct patterns of childhood adversities: parental harshness and neglect, 1625 children (3.3%); parental separation and poverty, 8731 children (17.5%); family instability, 3655 children (7.3%); family loss, instability, and poverty, 1505 children (3.0%); and crowded housing and poverty, 9901 children (19.9%). Children in 4 of these groups had lower neurocognitive scores than children with a low probability of experiencing adversity, with standardized mean differences ranging from -0.07 (95% CI, -0.11 to -0.03) to -0.86 (95% CI, -1.06 to -0.65).

Conclusions and Relevance

These findings suggest that adverse childhood experiences are associated with deficits in children's neurocognitive functions. It is important to understand the complexity in children's exposure to adversity and the resulting developmental consequences, as well as the underlying mechanisms, to help support children exposed to adversity and foster healthier and resilient trajectories of development.

Burden of Mental Disorders and Suicide Attributable to Childhood Maltreatment

Importance

The proportion of mental disorders and burden causally attributable to childhood maltreatment is unknown.

Objective

To determine the contribution of child maltreatment to mental health conditions in Australia, accounting for genetic and environmental confounding.

Design, Setting, and Participants

This meta-analysis involved an epidemiological assessment accounting for genetic and environmental confounding between maltreatment and mental health and 3 cross-sectional national surveys: the Australian Child Maltreatment Study (ACMS) 2023, National Study of Mental Health and Well-being 2020-2022, and Australian Burden of Disease Study 2023. Causal estimates were derived on the association between childhood maltreatment and mental health conditions from a meta-analysis of quasi-experimental studies. This was combined with the prevalence of maltreatment from the ACMS to calculate the population attributable fraction (PAF). The PAF was applied to the number and burden of mental health conditions in Australia, sourced from 2 population-based, nationally representative surveys of Australians aged 16 to 85 years, to generate the number and associated burden of mental disorders attributable to child maltreatment.

Exposure

Physical abuse, sexual abuse, emotional abuse, or neglect prior to age 18 years.

Main Outcomes and Measures

Proportion and number of cases, years of life lost, years lived with disability, and disability-adjusted life-years of mental health conditions (anxiety, depression, harmful alcohol and drug use, self-harm, and suicide attempt) attributable to childhood maltreatment.

Results

Meta-analytic estimates were generated from 34 studies and 54 646 participants and applied to prevalence estimates of childhood maltreatment generated from 8503 Australians. Childhood maltreatment accounted for a substantial proportion of mental health conditions, ranging from 21% (95% CI, 13%-28%) for depression to 41% (95% CI, 27%-54%) of suicide attempts. More than 1.8 million cases of depressive, anxiety, and substance use disorders could be prevented if childhood maltreatment was eradicated. Maltreatment accounted for 66 143 years of life lost (95% CI, 43 313-87 314), primarily through suicide, and 184 636 disability-adjusted life-years (95% CI, 109 321-252 887).

Conclusions and Relevance

This study provides the first estimates of the causal contribution of child maltreatment to mental health in Australia. Results highlight the urgency of preventing child maltreatment to reduce the population prevalence and burden of mental disorders.

The relationship between type, timing and duration of exposure to adverse childhood experiences and adolescent self-harm and depression: findings from three UK prospective population-based cohorts

BACKGROUND

Adverse childhood experiences (ACEs) are well-established risk factors for self-harm and depression. However, despite their high comorbidity, there has been little focus on the impact of developmental timing and the duration of exposure to ACEs on co-occurring self-harm and depression.

METHODS

Data were utilised from over 22,000 children and adolescents participating in three UK cohorts, followed up longitudinally for 14-18 years: the Avon Longitudinal Study of Parents and Children (ALSPAC), the Millennium Cohort Study (MCS) and the Environmental Risk (E-Risk) Longitudinal Twin Study. Multinomial logistic regression models estimated associations between each ACE type and a four-category outcome: no self-harm or depression, self-harm alone, depression alone and self-harm with co-occurring depression. A structured life course modelling approach was used to examine whether the accumulation (duration) of exposure to each ACE, or a critical period (timing of ACEs) had the strongest effects on self-harm and depression in adolescence.

RESULTS

The majority of ACEs were associated with co-occurring self-harm and depression, with consistent findings across cohorts. The importance of timing and duration of ACEs differed across ACEs and across cohorts. For parental mental health problems, longer duration of exposure was strongly associated with co-occurring self-harm and depression in both ALSPAC (adjusted OR: 1.18, 95% CI: 1.10-1.25) and MCS (1.18, 1.11-1.26) cohorts. For other ACEs in ALSPAC, exposure in middle childhood was most strongly associated with co-occurring self-harm and depression, and ACE occurrence in early childhood and adolescence was more important in the MCS.

CONCLUSIONS

Efforts to mitigate the impact of ACEs should start in early life with continued support throughout childhood, to prevent long-term exposure to ACEs contributing to risk of self-harm and depression in adolescence.

Childhood maltreatment and health in the UK Biobank: triangulation of outcome-wide and polygenic risk score analyses

BACKGROUND

Childhood maltreatment is common globally and impacts morbidity, mortality, and well-being. Our understanding of its impact is constrained by key substantive and methodological limitations of extant research, including understudied physical health outcomes and bias due to unmeasured confounding. We address these limitations through a large-scale outcome-wide triangulation study.

METHODS

We performed two outcome-wide analyses (OWAs) in the UK Biobank. First, we examined the relationship between self-reported maltreatment exposure (number of maltreatment types, via Childhood Trauma Screener) and 414 outcomes in a sub-sample of 157,316 individuals using generalized linear models ("observational OWA"). Outcomes covered a broad range of health themes including health behaviors, cardiovascular disease, digestive health, socioeconomic status, and pain. Second, we examined the relationship between a polygenic risk score for maltreatment and 298 outcomes in a non-overlapping sample of 243,006 individuals ("genetic OWA"). We triangulated results across OWAs based on differing sources of bias.

RESULTS

Overall, 23.8% of the analytic sample for the observational OWA reported at least one maltreatment type. Of 298 outcomes examined in both OWAs, 25% were significant in both OWAs and concordant in the direction of association. Most of these were considered robust in the observational OWA according to sensitivity analyses and included outcomes such as marital separation (OR from observational OWA, ORo = 1.25 (95% CI: 1.21, 1.29); OR from genetic OWA, ORg = 1.06 (1.03, 1.08)), major diet changes due to illness (ORo = 1.27 (1.24, 1.29); ORg = 1.01 (1.00, 1.03)), certain intestinal diseases (ORo = 1.14 (1.10, 1.18); ORg = 1.03 (1.01, 1.06)), hearing difficulty with background noise (ORo = 1.11 (1.11, 1.12); ORg = 1.01 (1.00, 1.01)), knee arthrosis (ORo = 1.13 (1.09, 1.18); ORg = 1.03 (1.01, 1.05)), frequent sleeplessness (ORo = 1.21 (1.20, 1.23); ORg = 1.02 (1.01, 1.03)), and low household income (ORo = 1.28 (1.26, 1.31); ORg = 1.02 (1.01, 1.03)). Approximately 62% of results were significant in the observational OWA but not the genetic OWA, including numerous cardiovascular outcomes. Only 6 outcomes were significant in the genetic OWA and null in the observational OWA; these included diastolic blood pressure and glaucoma. No outcomes were statistically significant in opposite directions in the two analyses, and 11% were not significant in either OWA.

CONCLUSIONS

Our findings underscore the far-reaching negative effects of childhood maltreatment in later life and the utility of an outcome-wide triangulation design with sensitivity analyses for improving causal inference.

Emotion Regulation, Parenting, and Psychopathology: A Systematic Review

The presence of a parental mental disorder can lead to adverse outcomes for children. Difficulties in emotion regulation are observed across a range of mental health problems and may play a crucial role in this context. Following PRISMA guidelines, we systematically searched Medline, PsycINFO, Embase, and Web of Science for studies examining the association between emotion regulation in parents with psychopathology at a clinical or subclinical level and their parenting. The protocol was registered with the PROSPERO international prospective register of systematic reviews (CRD42021224954; January 2021). A total of 23 studies were included in the qualitative synthesis. Emotion regulation was predominantly assessed using self-report on the general ability (e.g., Difficulties in Emotion Regulation Scale). The assessment of parenting encompassed a broad range of aspects and operationalizations. Across psychopathology in parents, several aspects of difficulties in emotion regulation were associated with unfavorable emotion socialization, more negative parenting, and partially with less positive parenting. Slightly different effects were observed for posttraumatic stress disorder and anxiety disorders. For parents with depressive disorders, specific emotion regulation strategies (suppression, reappraisal) seem to buffer against negative parenting. Since the majority of studies refer only to mothers, generalization to fathers is limited. Furthermore, conclusions are limited due to study heterogeneity and lack of prospective studies. Nevertheless, findings suggest that interventions should target the improvement of emotion regulation in parents with psychopathology.

Editorial Perspective: Misaligned incentives in mental health research - the case for Registered Reports

Current incentive structures reward mental health researchers for producing positive, novel, and clean results. This can promote questionable research practices which contribute to a distorted evidence base, in turn limiting progress in mental health research. Registered Reports (RRs) offer a solution to realign the incentives towards conducting high-quality, rigorous, and accurate studies, by preventing publication and reporting biases. However, the uptake of RRs in mental health research has so far been limited. This editorial perspective highlights the advantages of RRs for mental health research, before discussing potential challenges and how they can be addressed. Greater uptake of RRs in mental health research could help to promote a fairer research culture, limit publication bias and questionable research practices, and ultimately, improve understanding of mental health.

Improving the Way that We Conceptualise Adverse Childhood Experiences - A Commentary on Sisitsky et al. (2023)

Research on adverse childhood experiences (ACEs) has traditionally relied on cumulative ACE scores, which prevents understanding about the effects of distinct adversities and their mechanistic pathways. Dimensional and person-centred approaches have been proposed as alternative methods to conceptualise ACEs, which address limitations of the cumulative ACE score. In this issue, Sisitsky et al. (Research on Child and Adolescent Psychopathology, 2023) apply these approaches to identify dimensions of ACEs and profiles of children with distinct patterns of early exposure, in a large, racially diverse cohort from the US. The authors also examine the longitudinal associations between profiles of early adversity in early childhood with later mental health and telomere length. In this commentary, we discuss key findings from the study and recommend future avenues for improving the conceptualisation of ACEs.

Genetic Decomposition of the Heritable Component of Reported Childhood Maltreatment

Background

Decades of research have shown that environmental exposures, including self-reports of trauma, are partly heritable. Heritable characteristics may influence exposure to and interpretations of environmental factors. Identifying heritable factors associated with self-reported trauma could improve our understanding of vulnerability to exposure and the interpretation of life events.

Methods

We used genome-wide association study summary statistics of childhood maltreatment, defined as reporting of abuse (emotional, sexual, and physical) and neglect (emotional and physical) (N = 185,414 participants). We calculated genetic correlations (rg) between reported childhood maltreatment and 576 traits to identify phenotypes that might explain the heritability of reported childhood maltreatment, retaining those with |rg| > 0.25. We specified multiple regression models using genomic structural equation modeling to detect residual genetic variance in childhood maltreatment after accounting for genetically correlated traits.

Results

In 2 separate models, the shared genetic component of 12 health and behavioral traits and 7 psychiatric disorders accounted for 59% and 56% of heritability due to common genetic variants (single nucleotide polymorphism-based heritability [h2SNP]) of childhood maltreatment, respectively. Genetic influences on h2SNP of childhood maltreatment were generally accounted for by a shared genetic component across traits. The exceptions to this were general risk tolerance, subjective well-being, posttraumatic stress disorder, and autism spectrum disorder, identified as independent contributors to h2SNP of childhood maltreatment. These 4 traits alone were sufficient to explain 58% of h2SNP of childhood maltreatment.

Conclusions

We identified putative traits that reflect h2SNP of childhood maltreatment. Elucidating the mechanisms underlying these associations may improve trauma prevention and posttraumatic intervention strategies.

Transmit Radiant Individuality to Offspring (TRIO) study: investigating intergenerational transmission effects on brain development

Intergenerational transmission is a crucial aspect of human development. Although prior studies have demonstrated the continuity of psychopathology and maladaptive upbringing environments between parents and offspring, the underlying neurobiological mechanisms remain unclear. We have begun a novel neuroimaging research project, the Transmit Radiant Individuality to Offspring (TRIO) study, which focuses on biological parent-offspring trios. The participants of the TRIO study were Japanese parent-offspring trios consisting of offspring aged 10-40 and their biological mother and father. Structural and functional brain images of all participants were acquired using magnetic resonance imaging (MRI). Saliva samples were collected for DNA analysis. We obtained psychosocial information, such as intelligence, mental health problems, personality traits, and experiences during the developmental period from each parent and offspring in the same manner as much as possible. By April 2023, we completed data acquisition from 174 trios consisting of fathers, mothers, and offspring. The target sample size was 310 trios. However, we plan to conduct genetic and epigenetic analyses, and the sample size is expected to be expanded further while developing this project into a multi-site collaborative study in the future. The TRIO study can challenge the elucidation of the mechanism of intergenerational transmission effects on human development by collecting diverse information from parents and offspring at the molecular, neural, and behavioral levels. Our study provides interdisciplinary insights into how individuals' lives are involved in the construction of the lives of their descendants in the subsequent generation.

Protocol for secondary data analysis of 4 UK cohorts examining youth adversity and mental health in the context of intersectionality

BACKGROUND

Youth adversity (e.g., abuse and bullying victimisation) is robust risk factor for later mental health problems (e.g., depression and anxiety). Research shows the prevalence of youth adversity and rates of mental health problems vary by individual characteristics, identity or social groups (e.g., gender and ethnicity). However, little is known about whether the impact of youth adversity on mental health problems differ across the intersections of these characteristics (e.g., white females). This paper reports on a component of the ATTUNE research programme (work package 2) which aims to investigate the impact and mechanisms of youth adversity on depressive and anxiety symptoms in young people by intersectionality profiles.

METHODS

The data are from 4 UK adolescent cohorts: HeadStart Cornwall, Oxwell, REACH, and DASH. These cohorts were assembled for adolescents living in distinct geographical locations representing coastal, suburban and urban places in the UK. Youth adversity was assessed using a series of self-report questionnaires and official records. Validated self-report instruments measured depressive and anxiety symptoms. A range of different variables were classified as possible social and cognitive mechanisms.

RESULTS AND ANALYSIS

Structural equation modelling (e.g., multiple group models, latent growth models) and multilevel modelling will be used, with adaptation of methods to suit the specific available data, in accord with statistical and epidemiological conventions.

DISCUSSION

The results from this research programme will broaden our understanding of the association between youth adversity and mental health, including new information about intersectionality and related mechanisms in young people in the UK. The findings will inform future research, clinical guidance, and policy to protect and promote the mental health of those most vulnerable to the negative consequences of youth adversity.

Interpersonal early adversity demonstrates dissimilarity from early socioeconomic disadvantage in the course of human brain development: A meta-analysis

It has been established that early-life adversity impacts brain development, but the role of development itself has largely been ignored. We take a developmentally-sensitive approach to examine the neurodevelopmental sequelae of early adversity in a preregistered meta-analysis of 27,234 youth (birth to 18-years-old), providing the largest group of adversity-exposed youth to date. Findings demonstrate that early-life adversity does not have an ontogenetically uniform impact on brain volumes, but instead exhibits age-, experience-, and region-specific associations. Relative to non-exposed comparisons, interpersonal early adversity (e.g., family-based maltreatment) was associated with initially larger volumes in frontolimbic regions until ∼10-years-old, after which these exposures were linked to increasingly smaller volumes. By contrast, socioeconomic disadvantage (e.g., poverty) was associated with smaller volumes in temporal-limbic regions in childhood, which were attenuated at older ages. These findings advance ongoing debates regarding why, when, and how early-life adversity shapes later neural outcomes.

Association between childhood maltreatment and callous-unemotional traits in youth: A meta-analysis

Callous-unemotional (CU) traits (i.e., lack of remorse or guilt, callous lack of empathy, deficient concern for the feelings of others) in youth with conduct problems confer risk for a particularly severe and persistent form of antisocial behaviour. Previous research has linked childhood maltreatment as a potential risk factor for CU traits, both primary (i.e., genetically underpinned) and secondary (i.e., environmentally influenced) variants, but findings have been inconsistent, and the association has not yet been tested in a meta-analysis. To address this gap, we conducted a meta-analysis to assess the nature and strength of the associations between childhood maltreatment and its subtypes with CU traits and potential variants (i.e., primary and secondary CU traits). A systematic search identified 29 eligible studies including 9,894 participants (42% female) between the ages of 3 and 18 years (Mage=14.22 years, SD = 1.07). Results revealed a significant moderate positive association between childhood maltreatment and CU traits. All subtypes of maltreatment bar sexual abuse were significantly associated with CU traits. However, it was not possible to compare primary and secondary CU traits directly due to inconsistencies in how they are defined. The limitations posed by current research signal the need for clinical and operational guidelines on how to define primary and secondary CU traits. Additionally, prospective longitudinal, genetically informed research is needed to clarify if maltreatment is a causal risk factor for CU traits.

How adverse and benevolent childhood experiences influence depression and suicidal ideation in Chinese undergraduates: a latent class analysis

BACKGROUND

There has been minimal research on the role of benevolent childhood experiences (BCEs) and how such events may offer protection from the insidious effects of adverse childhood experiences (ACEs) or later in life.

OBJECTIVES

This research aims to learn how BCEs and ACEs interact to affect adolescents' psychological distress.

METHODS

Cross-sectional survey was conducted in three cities (Xuzhou, Nanjing, and Wuhan) in China from March 2021 to May 2021. Latent class analysis (LCA) was used to classify the patterns of ACEs and BCEs. We adopted hierarchical multivariable regression to examine the influences of ACEs and BCEs on depression and suicidal ideation.

RESULTS

To explore the relationship between childhood experience and suicidal ideation and depression, LCA revealed three patterns of ACEs: (1) emotional abuse (10.57%); (2) high ACEs (0.55%); and (3) low ACEs classes (88.88%). Adolescents with emotional abuse (depression: OR = 3.82, 95%CI = 2.80-5.22, P < 0.001; suicidal ideation: OR = 5.766, 95%CI = 3.97-8.38, P < 0.001) and high ACEs class (suicidal ideation: OR = 5.93, 95%CI = 1.19-29.66, P < 0.05) had an increased risk of psychological distress (reference: low ACEs). LCA revealed four patterns of BCEs: (1) relationship support (14.54%); (2) low BCEs (4.85%); (3) high BCEs (55.34%); and (4) high quality of life classes (25.28%). Adolescents with a high quality of life (depression: OR = 0.09, 95%CI = 0.05-0.16, P < 0.001; suicidal ideation: OR = 0.22, 95%CI = 0.12-0.40, P < 0.001) and high BCEs (depression: OR = 0.05, 95%CI = 0.03-0.09, P < 0.001; suicidal ideation: OR = 0.15, 95%CI = 0.09-0.26, P < 0.001) protected the mental health of adolescents (reference: low BCEs).

CONCLUSIONS

High ACEs and emotional abuse classes were significantly associated with poorer mental health symptoms, including suicidal ideation and depression. In contrast, high BCEs and high quality of life classes were associated with better mental health. These findings point out that it is more necessary to identify and support victims of ACEs, and it is urgent to increase BCEs in early childhood.