Why do depression, conduct, and hyperactivity symptoms co-occur across adolescence? The role of stable and dynamic genetic and environmental influences

Examining intergenerational risk factors for conduct problems using polygenic scores in the Norwegian Mother, Father and Child Cohort Study

The aetiology of conduct problems involves a combination of genetic and environmental factors, many of which are inherently linked to parental characteristics given parents' central role in children's lives across development. It is important to disentangle to what extent links between parental heritable characteristics and children's behaviour are due to transmission of genetic risk or due to parental indirect genetic influences via the environment (i.e., genetic nurture). We used 31,290 genotyped mother-father-child trios from the Norwegian Mother, Father and Child Cohort Study (MoBa), testing genetic transmission and genetic nurture effects on conduct problems using 13 polygenic scores (PGS) spanning psychiatric conditions, substance use, education-related factors, and other risk factors. Maternal or self-reports of conduct problems at ages 8 and 14 years were available for up to 15,477 children. We found significant genetic transmission effects on conduct problems for 12 out of 13 PGS at age 8 years (strongest association: PGS for smoking, β = 0.07, 95% confidence interval = [0.05, 0.08]) and for 4 out of 13 PGS at age 14 years (strongest association: PGS for externalising problems, β = 0.08, 95% confidence interval = [0.05, 0.11]). Conversely, we did not find genetic nurture effects for conduct problems using our selection of PGS. Our findings provide evidence for genetic transmission in the association between parental characteristics and child conduct problems. Our results may also indicate that genetic nurture via traits indexed by our polygenic scores is of limited aetiological importance for conduct problems-though effects of small magnitude or effects via parental traits not captured by the included PGS remain a possibility.

Network structure of adolescent social, emotional, and behavioral difficulties and their differential relationships with suicidality

BACKGROUND

Social, emotional, and behavioral difficulties (SEBDs) tend to develop during adolescence. Their presence and especially co-occurrence induce numerous disrupting consequences, including suicidality. A recently developed network analysis is suitable to investigate the symptom-level structure of comorbid psychopathology. Rather than pairwise comorbidity networks, the current study investigated a comprehensive network of SEBDs at the symptom level and explored the differential relationships between symptoms of SEBDs and suicidality.

METHODS

Recruited from four public schools in China, a sample of adolescents (N = 6974, mean age = 15.84, 50.1% boys) were assessed with the Strengths and Difficulties Questionnaire (SDQ) and one suicidality-related item. The cross-sectional network structure of the SEBD symptoms was investigated. The differential associations between individual symptoms of SEBDs and suicidality were also explored with a relative importance analysis.

RESULTS

The results showed that constantly fidgeting, worry a lot, unhappy, down-hearted, tearful, and easily scared emerged as the most central symptoms in the network of SEBDs. Worry a lot, constantly fidgeting, lose my temper, and being bullied served as bridge symptoms, connecting various domains of SEBDs. In addition, the centrality of symptoms was positively associated with the variance shared with suicidality, with worry a lot and unhappy, down-hearted, and tearful explaining a large portion of the variance of suicidality.

CONCLUSIONS

Taken together, the results were indicative of close connections among emotional, hyperactivity-inattention, peer, and conduct aspects of adolescent mental health difficulties, as well as the central role of emotional difficulties in the SEBDs network.

Longitudinal relationship between depression and antisocial behaviors in Korean adolescents

Background

It is well known that depression and delinquency in adolescents are highly correlated, but longitudinal studies on the causal relationship between them are not active in East Asia compared to in Western culture. In addition, even the results of research on causal models and sex differences are inconsistent.

Objectives

This study examines the longitudinal reciprocal effects between depression and delinquent behavior in Korean adolescents based on sex differences.

Methods

We conducted multiple-group analysis by using an autoregressive cross-lagged model (ACLM). Longitudinal data from 2,075 individuals (2011-2013) were used for analysis. The longitudinal data are from the Korean Children and Youth Panel Survey (KCYPS), and data were used beginning with students at 14 years old (in the second grade of middle school) and tracked them until they were 16 (in the first grade of high school).

Results

Boys' delinquent behaviors at 15 years (the third grade of middle school) affected their depression at 16 years (the first grade of high school). In contrast, girls' depression at 15 years (the third grade of middle school) influenced their delinquent behaviors at 16 years (the first grade of high school).

Discussion

The findings support the failure model (FM) among adolescent boys and the acting-out model (ACM) among girls. The results imply that strategies to effectively prevent and treat delinquency and depression in adolescents must consider sex effects.

Shared genetic influences between depression and conduct disorder in children and adolescents: A systematic review

INTRODUCTION

The co-occurrence between major depression disorder (MDD) and conduct disorder (CD) is common across development and represents a significant risk factor for future psychiatric problems and long-term impairment. Large-scale quantitative genetic studies suggest that the MDD-CD co-occurrence may be partly explained by shared genetic vulnerability factors, in line with transdiagnostic models of psychopathology, but no systematic synthesis of the literature is currently available.

METHODS

We therefore conducted a systematic review of the available genetic literature on the co-occurrence between MDD and CD in children and adolescents. We identified 10 eligible studies, including 5 cross-sectional bivariate/multivariate twin studies, 3 longitudinal bivariate/multivariate twin studies, and 2 latent profile/trajectory twin studies.

RESULTS

Most of the reviewed studies found a strong contribution of shared genetic factors on the covariation between depression and conduct problems, in line with the prominent effect of a common genetic liability across development.

LIMITATIONS

The scientific literature on this psychiatric comorbidity is still limited, as it solely consists of twin studies from high income countries.

CONCLUSION

Considering the joint burden of MDD and CD on youth, families and society worldwide, future studies are needed to better investigate the shared risk processes of these frequently co-occurring conditions, in order to inform new treatments through personalized medicine.

Investigating the causal risk factors for self-harm by integrating Mendelian randomisation within twin modelling

Previous genetically informed studies have uncovered likely causal relationships between mental health problems and self-harm but resulting causal estimates may be biased due to unmediated pleiotropy. By fitting Mendelian Randomization - Direction of Causation (MR-DoC) models that explicitly model pleiotropy, we investigated the effect of four quantitatively measured mental health problems - major depressive disorder (MDD), schizophrenia, attention-deficit hyperactivity disorder (ADHD), and insomnia, on non-suicidal self-harm (NSSH) and suicidal self-harm (SSH), separately. We used data of 12,723 twins (56.6% females) in the Twins Early Development Study. Besides substantial pleiotropy, we found effects from child-rated depressive symptoms to both NSSH (β = 0.194, 95% CIs: 0.131, 0.257) and SSH (β = 0.210, 95% CIs: 0.125, 0.295). Similarly, effects flowed from parent-rated depressive symptoms to NSSH (β = 0.092, 95% CIs: 0.004, 0.181) and SSH (β = 0.165, 95% CIs: 0.051, 0.281). We did not find evidence of aetiological difference between NSSH and SSH.

Adolescent depression and adult labor market marginalization: a longitudinal cohort study

Adolescent depression is linked to adult ill-health and functional impairment, but recent research suggests that individual/contextual factors might account for this association. This study aimed to test whether the clinical heterogeneity of adolescent depression is related to marginalization from the labor market across early to middle adulthood. Data were drawn from the Uppsala Longitudinal Adolescent Depression Study, a community-based cohort initially assessed with structured clinical interviews at age 16-17. The cohort (n = 321 depressed; n = 218 nondepressed) was followed up after 2+ decades through linkage to nationwide population-based registries. Outcomes included consecutive annual data on unemployment, work disability, social welfare recipiency, and a composite marginalization measure, spanning from age 21 to 40. Longitudinal associations were examined using logistic regression analysis in a generalized estimating equations modeling framework. Subsequent depressive episodes and educational attainment in early adulthood were explored as potential pathways. The results showed that adolescent depression was associated with adult marginalization outcomes, but the strength of association varied across depressed subgroups. Adolescents with persistent depressive disorder had higher odds of all outcomes, including the composite marginalization measure (adjusted OR = 2.0, 95% CI = 1.4-2.7, p < 0.001), and this was partially (31%) mediated by subsequent depressive episodes in early adulthood. Exploratory moderation analysis revealed that entry into tertiary education mitigated the association with later marginalization, but only for adolescents with episodic major depression. In conclusion, the risk for future labor market marginalization is elevated among depressed adolescents, particularly those presenting with persistent depressive disorder. Targeted interventions seem crucial to mitigate the long-lasting impact of early-onset depression.

Association of Maternal Depressive Symptoms During the Perinatal Period With Oppositional Defiant Disorder in Children and Adolescents

IMPORTANCE

An association between perinatal maternal depression and risk of oppositional defiant disorder (ODD) in offspring has not been established. Identifying early determinants of ODD can help inform preventative intervention efforts.

OBJECTIVE

To investigate the association between maternal perinatal depressive symptoms and the risk of ODD in offspring aged 7 to 15 years.

DESIGN, SETTING, AND PARTICIPANTS

This population-based longitudinal birth cohort study used data from the Avon Longitudinal Study of Parents and Children (ALSPAC), in Bristol, UK. All pregnant women residents in Avon, UK, with expected delivery dates from April 1, 1991, to December 31, 1992, were invited to participate in the study. The study cohort ranged from approximately 8000 (at 7 years of age) to 4000 (at 15 years of age) mother-offspring pairs. Data were analyzed from November 2020 to July 2021.

MAIN OUTCOMES AND MEASURES

Maternal depressive symptoms were measured using the Edinburgh Postnatal Depression Scale (EPDS) antenatally at 18 and 32 weeks of gestation and postnatally at 8 weeks and 8 months. This study primarily used a cutoff score of 12 or more on the EPDS to identify mothers with symptoms of depression, and the continuous EPDS scores were used to confirm the results of the main analyses. Offspring ODD at 7, 10, 13, and 15 years of age were diagnosed using the parent-reported Development and Well-Being Assessment.

RESULTS

Of 7994 mother-offspring pairs for whom data were available on offspring ODD at 7 years, 4102 offspring (51.3%) were boys. The mean (SD) age of mothers was 28.6 (4.6) years. Maternal antenatal depressive symptoms (measured at 32 weeks of gestation) were associated with offspring ODD (adjusted odds ratio [AOR], 1.75; 95% CI, 1.33-2.31). Offspring of mothers with postpartum depressive symptoms at 8 weeks and 8 months were more than 2 times more likely to have a diagnosis of ODD over time (AOR at 8 weeks, 2.24 [95% CI, 1.74-2.90]; AOR at 8 months, 2.04 [95% CI, 1.55-2.68]), and maternal persistent depressive symptoms were associated with a 4-fold increased risk of offspring ODD (AOR, 3.59; 95% CI, 1.98-6.52).

CONCLUSIONS AND RELEVANCE

These findings suggest that perinatal depressive symptoms are associated with ODD in offspring and further support the need for early identification and management of prenatal and postnatal depression in women of childbearing age.

Adverse childhood experiences, daytime salivary cortisol, and depressive symptoms in early adulthood: a longitudinal genetically informed twin study

Dysregulated hypothalamic-pituitary-adrenal (HPA)-axis function might underlie the relationship between adverse childhood experiences (ACEs) and depression. However, limited research has examined the possible mediating role of the HPA-axis among young people using longitudinal data. Moreover, it remains unclear whether genetic influences could contribute to these associations. Participants were 290 children from the Twins Early Development Study. ACEs were assessed from age 3-11 years. We calculated a cumulative risk score and also derived different ACEs clusters using factor analysis and latent class analysis. HPA-axis activity was indexed by daytime salivary cortisol at age 11. Depressive symptoms were ascertained at age 21. Genetic liability to altered cortisol levels and elevated depressive symptoms was measured using a twin-based method. We performed causal mediation analysis with mixed-effects regression models. The results showed that ACEs cumulative exposure (b = -0.20, p = 0.03), bullying (b = -0.61, p = 0.01), and emotional abuse (b = -0.84, p = 0.02) were associated with lower cortisol levels at age 11. Among participants exposed to multiple ACEs, lower cortisol was related to higher depressive symptoms at age 21 (b = -0.56, p = 0.05). Lower cortisol levels mediated around 10-20% of the total associations of ACEs cumulative exposure, bullying, and dysfunctional parenting/emotional abuse with higher depressive symptoms. Genetic factors contributed to these associations, but the mediation effects of cortisol in the associations of ACEs cumulative exposure (b = 0.16 [0.02-0.34]) and bullying (b = 0.18 [0.01-0.43]) remained when genetic confounding was accounted for. In conclusion, ACEs were linked to elevated depressive symptoms in early adulthood partly through lower cortisol levels in early adolescence, and these relationships were independent of genetic confounding.

Advances in early identification of children and adolescents at risk for psychiatric illness

PURPOSE OF REVIEW

Childhood and adolescence are a crucial time window for the early identification of perspectival risk for adult psychopathology. This article reviews current advances in the field.

RECENT FINDINGS

Converging developmentally focused and predictive approaches are rapidly expanding in the field of early identification of children and adolescents at risk for psychiatric illness. Although the former emphasizes early phenotypic trajectories emerging in childhood and adolescence, the latter operate in terms of clinical risk staging. Decisive advances in the field include the metaanalytical evidence of the predictive value of clinical high-risk criteria in childhood-adolescence; the systematization of premorbid manifestations of psychotic vulnerability and bipolar prodromes; the corroboration of certain sets of anomalous subjective experiences as transdiagnostic index of familial genetic risk (i.e., basic symptoms) and early developmental expression of schizophrenia spectrum vulnerability (i.e., self-disorders).

SUMMARY

Childhood phenotypic manifestations of liability to mental disorders are often cooccurrent and undergo a plastic, heterotypic modification along the transition to adolescence. In general, they represent epiphenomenic flags of a broad vulnerability for the subsequent structuration of mental illness. This perspective coheres with the p-factor model of psychopathology and complements the clinical staging model which informs the early detection paradigm of severe mental disorders.