Childhood trajectories of internalising and externalising problems associated with a polygenic risk score for neuroticism in a UK birth cohort study

Neuroticism represents a personality disposition towards experiencing negative emotions more frequently and intensely. Longitudinal studies suggest that neuroticism increases risk of several psychological and physical problems. Improved understanding of how this trait manifests in early life could help inform preventative strategies in those liable to neuroticism. This study explored how a polygenic risk score (PRS) for neuroticism is expressed from infancy to late childhood across various psychological outcomes and how it associates with trajectories of internalising and externalising problems from ages 4-11 in the Avon Longitudinal Study of Parents and Children (N=5,279). We employed multivariable linear and ordinal regression models to estimate associations between a child neuroticism PRS and psychological outcomes. A three-level mixed-effect model was employed to characterise child internalising and externalising trajectories and estimate how a child PRS associated with both their overall levels and rates of change. We found evidence that the PRS for neuroticism was associated with a more sensitive temperament in early infancy in addition to higher emotional and behavioural problems and a higher risk of being diagnosed with a variety of clinical disorders, particularly anxiety disorders, in childhood. We also found strong evidence that the PRS for neuroticism was associated with overall levels of internalising and externalising trajectories, with a larger magnitude of effect on the internalising trajectory. The PRS was also associated with slower rates of reduction of internalising problems. Our findings using a large, well-characterised birth cohort study suggest that phenotypic manifestations of a PRS for adult neuroticism can be detected as early as in infancy and that this PRS associates with several mental health problems and differences in emotional trajectories across childhood.

Eating disorders symptoms and excessive internet use in adolescents: the role of internalising and externalising problems

Background Both eating disorders and excessive internet use represent significant health issues for contemporary adolescents. Yet, the link between them has seldom been investigated. We aim to study this association through their common underlying psychological factors: internalising problems and externalising problems. Methods A representative sample of 7,083 adolescents (Mage = 13.48 years; SDage = 1.32; 50.3% girls) from Slovakia was obtained from the Health Behaviour in School-aged Children (HBSC) project in 2018. Study variables included the Excessive Internet Use Scale (EIU) and the Strength and Difficulties Questionnaire (SDQ). Eating disorders symptoms (EDS) were assessed by SCOFF and selected items from the Eating Disorder Screen for Primary Care (ESP). Data were analysed separately for boys and girls with Structural Equation Modelling. Results There was a partial correlation between EDS and EIU (r = 0.36 for boys and r = 0.29 for girls) after controlling for the internalising and externalising of problems. Internalising and externalising problems were positively associated with EDS, while EIU was only associated with externalising problems. The results were comparable for both genders. Conclusion The study provides evidence that, during adolescence, EDS and EIU are related and have a tendency to occur together. Also, they are related even when controlled for their shared underlying psychological factors, namely the emotional and attentional/behavioural difficulties.

Cognition, Behaviour, and Mental Health in Struggling Learners: A Spotlight on Girls

Objectives: Fewer girls than boys are identified as struggling at school. The objectives of this study were to: i) identify dimensions of cognition, behaviour and mental health in a unique transdiagnostic sample of struggling learners; ii) test whether these constructs were equivalent for boys and girls, and; iii) compare their performance across the dimensions. Methods: 805 school-aged children, identified by practitioners as experiencing problems in cognition and learning, completed cognitive assessments, and parents/carers rated their behaviour and mental health problems. Results: Three cognitive, three behavioural, and two mental health dimensions distinguished the sample. Dimensions were structurally comparable between boys and girls, but differences in severity were present: girls had greater cognitive impairments; boys had more severe externalising problems. Conclusions: Gender biases to stereotypically male behaviours are prevalent among practitioners, even when the focus is on identifying cognitive and learning difficulties. This underscores the need to include cognitive and female-representative criteria in diagnostic systems to identify girls whose difficulties could go easily undetected.

Young Adulthood Outcomes of Joint Mental Health Trajectories: A Group-Based Trajectory Model Analysis of a 13-Year Longitudinal Cohort Study

Developmental trajectories of common mental health issues such as ADHD symptoms, internalising problems, and externalising problems can often be usefully summarised in terms of a small number of ‘developmental subtypes’ (e.g., ‘childhood onset’, ‘adolescent onset’) that may differ in their profiles or levels of clinically meaningful variables such as etiological risk factors. However, given the strong tendency for symptoms in these domains to co-occur, it is important to consider not only developmental subtypes in each domain individually, but also the joint developmental subtypes defined by symptoms trajectories in all three domains together (e.g., ‘late onset multimorbid’, ‘pure internalising’, ‘early onset multimorbid’). Previous research has illuminated the joint developmental subtypes of ADHD symptoms, internalising problems, and externalising problems that emerge from normative longitudinal data using methods such as group-based trajectory modelling, as well as predictors of membership in these developmental subtypes. However, information on the long-term outcomes of developmental subtype membership is critical to illuminate the likely nature and intensity of support needs required for individuals whose trajectories fit different developmental subtypes. We, therefore, evaluated the relations between developmental subtypes previously derived using group-based trajectory modelling in the z-proso study (n = 1620 with trajectory data at ages 7, 8, 9, 10, 11, 12, 13, 15) and early adulthood outcomes. Individuals with multimorbid trajectories but not ‘pure’ internalising problem elevations showed higher levels of social exclusion and delinquency at age 20. These associations held irrespective of the specific developmental course of symptoms (e.g., early versus late onset versus remitting). There was also some evidence that intimate partner violence acts as a form of heterotypic continuity for earlier externalising problems. Results underline the need for early intervention to address the pathways that lead to social exclusion and delinquency among young people with multiple co-occurring mental health issues.

Sibling Bullying: A Prospective Longitudinal Study of Associations with Positive and Negative Mental Health during Adolescence

It is well documented that sibling bullying is associated with poor mental health. The prospective longitudinal relationships between sibling bullying and both positive and negative mental health remain unclear. Additionally, the developmental course of negative mental health after sibling bullying involvement is yet to be investigated. Regression models were fitted to data from a UK-based Millennium Cohort Study (n=17,157, 48% female). Adolescents self-reported on sibling bullying in early- (age 11 years) and mid-adolescence (14 years) and on positive (general well-being and self-esteem) and negative mental health (internalising problems, externalising problems, psychological distress, and self-harm) in late adolescence (17 years). Primary caregivers also reported on internalising and externalising problems throughout adolescence. Sibling bullying involvement as a victim-only or bully-victim in early adolescence was associated with more symptoms of negative mental health and lower levels of positive mental health in late adolescence compared to those not involved in any sibling bullying. Being a bully-only was associated with externalising problems but no other aspect of mental health in late adolescence. Persistent sibling bullying victimisation in early- and mid-adolescence was associated with more symptoms of negative mental health and reduced positive mental health in late adolescence. Finally, the developmental course of externalising, but not internalising, problems during adolescence differed depending on the sibling bullying role in early adolescence. These findings suggest that, if causality can be established, sibling bullying in early adolescence likely affects the developmental course of externalising problems and has a detrimental effect both positive and negative mental health in late adolescence.

Is frontoamygdalar connectivity in the resting brain linked with externalising behaviours during development?

Externalising problems tend to vary over the course of development, but often peak in late adolescence. Data suggest that the frontoamygdalar brain circuitry (involved in emotion regulation) might have an important role in mediating externalising behaviour.

Mediating Factors in Within-Person Developmental Cascades of Externalising, Internalising and ADHD Symptoms in Childhood

This study investigated the role of parental involvement alongside academic achievement and peer problems in mediating within-person developmental cascades from externalising to internalising problems and from ADHD symptoms to internalising and externalising problems using autoregressive latent trajectory models with structured residuals. Models were fit for parent- and teacher-reports on children’s psychosocial development as measured by the Social Behaviour Questionnaire (SBQ) collected over ages 7, 9, and 11 in a Swiss longitudinal cohort study (zproso; N=1387, 51% male). Results indicated that none of the considered factors acted as significant mediators in longitudinal relations between ADHD, internalising and externalising problems; hence, a full picture of the mediating mechanisms in developmental cascades remains to be identified.