South Korean Population Study Finds Child ADHD Impacts Maternal, but Not Paternal, Mental Health

A large international research team has just released a detailed analysis of studies looking at the connection between parents' mental health conditions and their children's mental health, particularly focusing on ADHD (Attention Deficit Hyperactivity Disorder). This analysis, called a meta-analysis, involved carefully examining previous studies on the subject. By September 2022, they had found 211 studies, involving more than 23 million people, that could be combined for their analysis.

Most of the studies focused on mental disorders other than ADHD. However, when they specifically looked at ADHD, they found five studies with over 6.7 million participants. These studies showed that children of parents with ADHD were more than eight times as likely to have ADHD compared to children whose parents did not have ADHD. The likelihood of this result happening by chance was extremely low, meaning the connection between parental ADHD and child ADHD is strong.

Understanding the Numbers: How Likely Is It for a Child to Have ADHD?

The researchers wanted to figure out how common ADHD is among children of parents both with and without ADHD. To do this, they first analyzed 65 studies with about 2.9 million participants, focusing on children whose parents did not have ADHD. They found that around 3% of these children had ADHD.

Next, they analyzed five studies with over 44,000 cases where the parents did have ADHD. In this group, they found that 32% of the children also had ADHD, meaning about one in three. This is a significant difference—children of parents with ADHD are about ten times more likely to have the condition than children whose parents who do not have ADHD.

How Does This Compare to Other Mental Disorders in Parents?

The researchers also wanted to see if other mental health issues in parents, besides ADHD, were linked to ADHD in their children. They analyzed four studies involving 1.5 million participants and found that if a parent had any mental health disorder (like anxiety, depression, or substance use issues), the child’s chances of having ADHD increased by 80%. However, this is far less than the 840% increase seen in children whose parents specifically had ADHD. In other words, ADHD is much more likely to be passed down in families compared to other mental disorders.

Strengths and Weaknesses of the Research

The study had a lot of strengths, mainly due to the large number of participants involved, which helps make the findings more reliable. However, there were also some limitations:

• The researchers did not look into "publication bias," which means they didn’t check whether only certain types of studies were included (those showing stronger results, for example), which could make the findings seem more extreme.
• The team reported that differences between the studies were measured, but they didn’t explain clearly how these differences affected the results.
• Most concerning, the researchers admitted that 96% of the studies they included had a "high risk of bias," meaning that many of the studies might not have been entirely reliable.

Conclusion

Despite these limitations, the research team concluded that their analysis provides strong evidence that children of parents with ADHD or other serious mental health disorders are at a higher risk of developing mental disorders themselves. While more research is needed to fill in the gaps, the findings suggest that it would be wise to carefully monitor the mental health of children whose parents have these conditions to provide support and early intervention if needed

‍

Raising children is not easy. I should know.

As a clinical psychologist, I've helped parents learn the skills they need to be better parents. And my experience raising three children confirmed my clinical experience.

Parenting is a tough job under the best of circumstances, but it is even harder if the parent has ADHD.

For example, an effective parent establishes rules and enforces them systematically. This requires attention to detail, self-control, and good organizational skills. Given these requirements, it is easy to see how ADHD symptoms interfere with parenting. These observations have led some of my colleagues to test the theory that treating ADHD adults with medication would improve their parenting skills. I know about two studies that tested this idea.

In 2008, Dr. Chronis-Toscano and colleagues published a study using a sustained-release form of methylphenidate for mothers with ADHD. As expected, the medication decreased their symptoms of inattention and hyperactivity/impulsivity. The medication also reduced the mother's use of inconsistent discipline and corporal punishment and improved their monitoring and supervision of their children.

In a 2014 study, Waxmonsky and colleagues observed ADHD adults and their children in a laboratory setting once when the adults were off medication and once when they were on medication. They used the same sustained-release form of amphetamine for all the patients. As expected, the medications reduced ADHD symptoms in the parents. This laboratory study is especially informative because the researchers made objective ratings of parent-child interactions, rather than relying on the parents' reports of those interactions. Twenty parents completed the study. The medication led to less negative talk and commands and more praise by parents. It also reduced negative and inappropriate behaviors in their children.

Both studies suggest that treating ADHD adults with medication will improve their parenting skills. That is good news. But they also found that not all parenting behaviors improved. That makes sense. Parenting is a skill that must be learned. Because ADHD interferes with learning, parents with the disorder need time to learn these skills. Medication can eliminate some of the worst behaviors, but doctors should also provide adjunct behavioral or cognitive-behavioral therapies that could help ADHD parents learn parenting skills and achieve their full potential as parents.

Previous population studies have shown that children with ADHD have a much higher risk of traumatic injuries than their normally developing peers, and that such risk can be greatly reduced with methylphenidate treatment.

But what about the parents of children with ADHD? How does their risk compare with that of parents of normally developing children?

Taiwan has a single-payer public health insurance system that maintains comprehensive healthcare records of virtually every resident.

A Taiwanese research team availed itself of the Taiwan Maternal and Child Health Database, which covers 99.8% of all births, to identify 81,401 fathers and 87,549 mothers who had at least one offspring with ADHD and 1,646,100 fathers and 1,730,941 mothers with no offspring with ADHD.

The team determined children's ADHD status based on either an inpatient diagnosis or four or more  diagnoses.

It looked for parental traumatic injuries including burn injury, fracture, and traumatic brain injury.

To address covariates, it adjusted for age, urbanicity, low-income level, and competing risk of death.

Adjusted for those covariates, parents of children with ADHD were 20% more likely to suffer bone fractures, 27% more likely to have traumatic brain injuries, and 30% more likely to have burn injuries requiring medical treatment than parents of normally developing children.

The elevated risks were significant across the board, but roughly twice as much s for mothers as for fathers of children with ADHD - up 30% vs 15% for bone fractures, up 35% vs 23% for burn injuries, and up 45% vs 21% for traumatic brain injuries.

The authors noted that ADHD is highly heritable and that the findings may in part point to undiagnosed adult ADHD.

Another contributing factor, they suggested, is that "studies have revealed that a high proportion of parents having children with ADHD experience depression and anxiety. Stress-related negative emotions (depression and anxiety) were shown to cause loss of concentration, thereby increasing the likelihood of accidental events such as traffic accidents and contributing to the increased risks of traumatic injury among parents of children  ADHD."

The much-higher elevated risk for mothers seems to support this hypothesis, because mothers continue to be the principal caregivers in Taiwan, and are thus more exposed to the behaviors of their children. The authors cited a study indicating that "diagnosis of ADHD for children was reported to be a predictor of increased caregiver burden."

They concluded, "Given that knowledge is fundamental to act, it is essential to educate the parents of children with ADHD on the increased risk of traumatic injuries they may have. ... The need for behavioral and pharmacological intervention in parents of children with ADHD should be evaluated, especially in the parents with undiagnosed ADHD or sub-threshold ADHD symptoms. It deserves further prospective studies with longer follow-up periods to explore whether undiagnosed ADHD, care burden of parents, and children's aggressive behaviors contribute to the increased risks of traumatic injuries in parents of children with ADHD."