ADHD: Is ADHD Inherited?
Friday, April 10, 2009 at 6:19PM 
About two weeks ago, a couple expecting their first child asked me an intriguing question as they interviewed me for the opportunity to be their pediatrician. They asked if ADHD was inherited. They were concerned because the father had been diagnosed as a child and took medication for many years. The scientific answer is clear. Yes, there is pretty good evidence that from studies of twins and epidemiologic studies of parents and children that if a parent had been diagnosed with ADHD, there was a much greater chance that the child will have ADHD.
ADHD is widely studied, and there are many things known about it. We know that children diagnosed with ADHD but untreated or ineffectively treated have much more problems in school than those whose ADHD is effectively treated. We know that teenagers with ADHD who are untreated have much higher rates of substance abuse problems than those whose ADHD is treated (yes, treated with speed-like medication). There’s a higher rate of ADHD in children raised in households without a father and in which the mother practices inconsistent, unstructured, discipline.
I started to assemble some of these facts. How would the adult with ADHD, untreated, parent a normal child? I'm guessing that there would be a lot of impulsive decisions, inconsistent discipline, and failed relationships. Growing up in a household with a parent with untreated ADHD is likely to make worse any existing problems in the child. It would make an anxious child more anxious, a depressed child more depressed. If the child had some behavior issues, these will become more of a problem with this kind of unstructured household and impulsive, distracted parenting. So a kid with some mild ADHD symptoms--and most normal kids have some (and most normal college students)--might act out enough to get in trouble at school. The impulsive parent might perceive some of these normal behaviors as impossible to manage. Now that the child is having trouble in school and at home, they might cross the diagnostic threshold and meet the official qualifications for ADHD.
Studies have shown that if you smoke, it's more likely that your children will smoke. Is smoking genetically inherited? Kids naturally follow the model behaviors of their parents, even the behaviors we don't want them to copy. But just maybe, children inherit some subtle feature of brain chemistry which responds powerfully to nicotine. So is smoking inherited? I'm not sure what that means.
Some parents with anxiety can't help but share their fears with their children. Won't this make their kids anxious? If the child has a little bit of anxiety of their own, will this make it worse? Does this mean the child inherited anxiety from the parent?
Is ADHD inherited? By studies that have been done on genetics and brain function, yes. But I suspect it is less often inherited when the affected parent has been effectively treated.
There's a couple of general parenting lessons here. First, you are not your parents. The things they did that didn't work for you as a child probably won't work on your own children. But most importantly, every child needs consistency and structure. The more disorganized and unstructured they are, the more valuable a structured environment and consistent parenting will be for them.
Next Post: Does ADHD exist?