I do like a gargantuan research study. Hence why I once did a post on 3 of the most epic ADHD studies ever done, or why I of course couldn’t resist writing about it when a genetic study came out last year involving over 20,000 ADHDers.
As far as big studies go, there’s a new one out that might take the cake. In it, researchers analyzed psychiatric data for an entire nation. And not a small nation either – Taiwan, which has a population of 23.58 million people.
The purpose of the study was to learn about the mental health of anyone who was a first-degree relative (parent, sibling or child) of someone who’d been diagnosed with ADHD. Altogether, the researchers found that there were:
- 220,996 parents who had children with ADHD
- 174,470 children who had brothers or sisters with ADHD
- 5,875 children who had parents with ADHD
In the study, researchers matched these people with demographically comparable people who didn’t have first-degree relatives with ADHD, then looked at rates psychiatric diagnoses. It turned out that the first-degree relatives were:
- 6.87 times as likely to have ADHD
- 4.14 times as likely to have autism spectrum disorder
- 2.21 times as likely to have bipolar disorder
- 2.08 higher risk of major depressive disorder
- 1.69 times as likely to have schizophrenia
The dramatically increased risk of ADHD isn’t exactly unexpected, since we know that ADHD has a large genetic component. Still, it’s nice to have some sense of how big the risk is for relatives of ADHDers from a study with a lot of data.
The increased risk for conditions other than ADHD is interesting because it’s consistent with the idea that genes involved in ADHD overlap with genes involved in other mental health conditions. This makes a certain sense when you consider that symptoms like impaired executive functions, atypical reward processing, and emotion dysregulation show up in other disorders besides ADHD.
I often say that if you have ADHD, there’s a good chance you have something else too, as people with ADHD commonly have “comorbid” conditions. But I might have to add to that: if you have ADHD, there’s a good chance someone in your family has ADHD and something else too!
Besides the practical implications here (encourage your family to seek help for any mental health conditions!), I think there’s also a more long-term implication for understanding what ADHD is. Researchers are only starting to get a feel for what ADHD has in common with other mental health conditions, and learning more about these areas of overlap might open up promising new possibilities for diagnosing and treating ADHD.
Image: Flickr/Olivia Raxter