Summary: Children with higher genetic risk for ADHD are more likely to experience childhood maltreatment, a new study shows. Researchers found that ADHD-associated genetic variants, especially when combined with parental psychiatric diagnoses, increase the likelihood of abuse and neglect.
Girls were also more frequently maltreated, though this was not linked to genetics, highlighting societal factors at play. The findings underscore the need to understand how genetic and environmental risks interact to better support vulnerable children.
Key Facts:
- ADHD Genetics: High ADHD genetic risk correlates with higher rates of childhood maltreatment.
- Parental Impact: Risk rises further if parents have a psychiatric diagnosis.
- Gender Disparity: Girls face more maltreatment, driven by societal rather than genetic factors.
Source: Aarhus University
Children who carry a particularly high number of genetic variants associated with ADHD also have a statistically greater risk of experiencing severe neglect and childhood maltreatment.
This is shown in a new study recently published in the scientific journal JAMA Psychiatry.
Researchers from the Department of Biomedicine at Aarhus University have examined how individuals’ genetic profiles relate to their risk of being subjected to childhood maltreatment – across five major psychiatric diagnoses such as ADHD and schizophrenia.
The results show that genetics is a risk factor. This is according to Ditte Demontis, professor of psychiatric genetics at the Department of Biomedicine and one of the researchers behind the study.
“One of the most striking findings is that children with a high genetic risk for ADHD are more often subjected to childhood maltreatment across all the psychiatric diagnoses we examined. When we looked specifically at children with ADHD, we found that among those with the highest genetic risk for ADHD, 5.6% were subjected to maltreatment. In comparison, only 3.3% of children with ADHD in the low genetic risk group experienced maltreatment,” she says.
In the study, childhood maltreatment is defined as exposure to physical, sexual, or emotional abuse and/or deprivation or severe neglect during childhood. The study builds on existing knowledge and clarifies that our genetics is a risk factor.
Environment and genetics interact
The risk of childhood maltreatment is also influenced by whether the child grows up with parents who themselves have a psychiatric diagnosis.
The study found that the risk of childhood maltreatment was 5.7% in the high genetic risk group if the child’s parents had a psychiatric diagnosis. By comparison, the risk was 2.5% in the same genetic high-risk group if the parents did not have a diagnosis.
“We can conclude that the combination of a child’s genetics – which may predispose them to externalizing behavior – and a psychiatric diagnosis in the parents are factors that increase the risk of childhood maltreatment,” explains Ditte Demontis.
The child is never to blame
The study also shows that girls are generally more exposed to childhood maltreatment than boys – but this is not genetically determined.
“This suggests that there are societal or social factors that result in girls being more often affected by childhood maltreatment,” the researcher says.
She emphasizes that neglect is never the child’s fault.
“A child’s genetics is never the cause. And the study does not show that children with ‘risk genetics’ will necessarily be maltreated. But statistically, it increases the risk, and by understanding the relevance of both genetic and environmental risk factors, we as a society might be able to intervene earlier and offer support,” she says.
Relevant for researchers and practitioners
This is the first time that researchers – with such a large dataset and genetic precision – have shown how genetics and known risk factors, such as parental mental illness, contribute to a particularly high risk of childhood maltreatment and neglect.
“The study shows correlations, but we do not yet know specifically how ADHD genetics increases the risk,” says Ditte Demontis.
The findings are especially relevant for researchers and professionals in psychiatry and genetics who work to understand the interaction between genes and environment.
“What’s new and more complex is that this study shows how genetic factors can increase the risk of being exposed to childhood maltreatment, and that ADHD genetics in particular increases the risk across all the psychiatric diagnoses studied. In doing so, the study builds on existing knowledge and adds a genetic layer to our understanding,” says Ditte Demontis.
Behind the research
- The study is basic research. The researchers used polygenic scores – a measure of how many genetic variants in a person’s genome are associated with a given psychiatric diagnosis or trait – to examine genetic differences between groups.
- Collaborators: Helen Minis, School of Health and Wellbeing, University of Glasgow, and Edmund Sonuga-Barke, Department of Child and Adolescent Psychiatry, Institute of Psychiatry, Psychology & Neuroscience, King’s College London
- External funding: Lundbeck Foundation, Novo Nordisk Foundation
About this genetics, ADHD, and child abuse research news
Author: Vibe Noordeloos
Source: Aarhus University
Contact: Vibe Noordeloos – Aarhus University
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Genetic Architecture and Risk of Childhood Maltreatment Across 5 Psychiatric Diagnoses” by Ditte Demontis et al. JAMA Psychiatry
Abstract
Genetic Architecture and Risk of Childhood Maltreatment Across 5 Psychiatric Diagnoses
Importance
Childhood maltreatment (CM) is associated with psychiatric disorders. The underlying mechanisms are complex and involve genetics.
Objective
To investigate the polygenic architecture of CM-exposed individuals across psychiatric conditions and if genetics modulates absolute CM risk in the presence of high-impact risk factors such as parental psychiatric diagnoses.
Design, Setting, and Participants
The population-based case-cohort iPSYCH was used to analyze 13 polygenic scores (PGS) in CM-exposed individuals across 5 psychiatric International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) diagnoses benchmarked against controls. Individuals were stratified into PGS quantiles, and absolute CM risk was calculated using Cox regression. Sex-specific analyses were also performed. Data were analyzed from June 2022 to December 2024.
Exposures
PGS of phenotypes of psychiatric disorders, CM, educational attainment, and substance use.
Main Outcomes and Measures
PGSs were generated using summary statistics from genome-wide association studies of phenotypes representing psychiatric disorders, CM, educational attainment, and substance use and tested for their association with CM across psychiatric disorders.
Results
This study included 102 856 individuals (mean [SD] age, 22.6 [7.1] years; 54 918 male [53.4%]) 8 to 35 years old. A total of 2179 CM-exposed individuals were analyzed across individuals with attention-deficit/hyperactivity disorder (ADHD; n = 22 674), autism (n = 18 941), schizophrenia (n = 6103), bipolar disorder (n = 3061), depression (n = 28 896), and controls (n = 34 689). PGSs for ADHD and educational attainment were associated with CM across all psychiatric diagnoses.
The absolute CM risk was increased in the highest PGS groups, eg, for ADHD, the absolute CM risk was 5.6% in the highest ADHD-PGS quartile whereas it was only 3.3% in the lowest ADHD-PGS quartile (hazard rate ratio quantile 4 vs quantile 1 = 1.81; 95% CI, 1.47-2.22). CM risk was more than twice as high for children with parents with a psychiatric diagnosis (5.7%) than for children with parents without a psychiatric diagnosis (2.5%), but even in the presence of this risk factor, individuals could still be stratified into risk groups based on their genetics.
No genetic differences between CM-exposed males and females were observed, but there were striking sex differences in absolute CM risk, which reached 5.6% for females in the highest ADHD-PGS quartile and 2.0% for males.
Conclusions and Relevance
Results of this case-control study suggest that individuals with high ADHD-PRS and/or low educational attainment–PRS had an associated elevated risk of CM. Extra attention should be given to individuals at high risk for CM across all 5 psychiatric diagnoses, ie, females with a high ADHD-PGS and/or a parent diagnosed with a psychiatric disorder.