Childhood maltreatment has been linked with an increased risk for multiple mental health problems, including depression, anxiety, post-traumatic stress disorder (PTSD), and substance abuse. Childhood abuse and neglect can have long-lasting impacts on an individual’s emotional and psychological development, leading to a higher risk of mental health problems in adulthood.
Abuse or neglect as a child can lead to a variety of mental health issues, according to a new study led by UCL researchers. The study, which was published in the American Journal of Psychiatry, aims to investigate the effects of childhood maltreatment on mental health while controlling for other genetic and environmental risk factors such as a family history of mental illness and socioeconomic disadvantage.
The groundbreaking study examined 34 quasi-experimental studies involving over 54,000 people. By using specialized samples (e.g., identical twins) or innovative statistical techniques to rule out other risk factors, quasi-experimental studies can better establish cause and effect in observational data. For example, in samples of identical twins, if a maltreated twin has mental health problems but their non-maltreated twin does not, the association cannot be due to genetics or the family environment shared between twins.
Researchers discovered small effects of child maltreatment on a variety of mental health problems, including internalizing disorders (such as depression, anxiety, self-harm, and suicide attempts), externalizing disorders (such as alcohol and drug abuse, ADHD, and conduct problems), and psychosis, across 34 studies.
This study provides strong evidence that childhood maltreatment has only a minor causal effect on mental health problems. Although minor, the effects of maltreatment could have far-reaching consequences, given that mental health issues predict a variety of negative outcomes, including unemployment, physical health problems, and premature death.
Dr. Jessie Baldwin
These effects held true regardless of the method or method by which maltreatment and mental health were assessed. According to the findings, preventing eight cases of child maltreatment would save one person from developing mental health problems.
Corresponding author, Dr. Jessie Baldwin (UCL Psychology & Language Sciences), said:
“It is well known that child maltreatment is associated with mental health problems, but it was unclear whether this relationship is causal, or is better explained by other risk factors.
“This study provides strong evidence that childhood maltreatment has only a minor causal effect on mental health problems. Although minor, the effects of maltreatment could have far-reaching consequences, given that mental health issues predict a variety of negative outcomes, including unemployment, physical health problems, and premature death. Interventions to prevent maltreatment are thus not only necessary for child welfare, but they may also prevent long-term suffering and financial costs associated with mental illness.”
Nevertheless, the researchers also found that part of the overall risk of mental health problems in individuals exposed to maltreatment was due to pre-existing vulnerabilities – which might include other adverse environments (eg. socioeconomic disadvantage) and genetic liability.
“Our findings also suggest that, in order to reduce the risk of mental health problems in individuals exposed to maltreatment, clinicians should address not only the maltreatment experience but also pre-existing psychiatric risk factors,” Dr. Baldwin said.
Childhood maltreatment was defined by researchers as any physical, sexual, or emotional abuse or neglect before the age of 18. Wellcome funded the research, which was carried out in collaboration with King’s College London, the University of Lausanne, Yale University School of Medicine, the University of Bristol, the NIHR Biomedical Research Center, and University Hospitals Bristol NHS Foundation Trust.
Study limitations
Each of the quasi-experimental studies examined could have been biased in some way. The findings, however, were consistent across studies using various quasi-experimental methods, indicating that the results are robust.
Furthermore, it was impossible to draw firm conclusions about the specific effects of different types of maltreatment because different types of abuse/neglect frequently occur concurrently, and studies rarely account for this.
Due to a lack of data, it was not possible to investigate the effects of maltreatment timing, the interval between maltreatment and mental health issues, or differences between racial or ethnic groups. To answer these questions, future quasi-experimental research is required.
