For many of us who grew up in the 1990s and 2000s, attention deficit hyperactivity disorder — better known as ADHD — seemed like a condition for kids.
But that perception is changing: Of the more than 15 million adults in America diagnosed with ADHD, about half of them got that diagnosis in adulthood. Laura Knouse, a licensed clinical psychologist and professor at University of Richmond, says that the condition can be a challenge to diagnose, leading to delays.
“If we think about the core features of ADHD, it’s characterized by age-inappropriate and impairing inattention and it can occur by itself or with hyperactivity impulsivity,” she said. “What we know about these kinds of symptoms is that they can be because of ADHD, but they could be the result of so many other mental health conditions or other kinds of lifestyle factors.”
How did we get to our current understanding of ADHD? And why has there been an uptick in diagnoses? Knouse answers these and other questions in the latest episode of Explain It to Me, Vox’s weekly call-in podcast.
Below is an excerpt of our conversation, edited for length and clarity. You can listen to the full episode on Apple Podcasts, Spotify, or wherever you get podcasts. If you’d like to submit a question, send an email to askvox@vox.com or call 1-800-618-8545.
Historically, when did we first hear about ADHD?
The traits we associate with ADHD probably have existed in humans as long as they have been humans. But in terms of the medical literature, we can rewind the clock all the way back to 1775. A German physician named Melchior Adam Weikard is now the first documented clinical case description.
It was also independently discovered in different places through the 1800s.
Then in the early 1900s, we start to see more mental disorders in general. ADHD didn’t become part of the diagnostic system that’s used in the United States until 1968, and the name of it has changed a number of times. It was first referred to as the hyperkinetic reaction of childhood. Then moving into the ’70s and ’80s, it evolved to not just focus on the behavior, but also the cognitive processes. That’s where we get a name change to attention deficit disorder.
It wasn’t really until the ’90s that, even in clinical spaces, the idea that ADHD persists into adulthood became a prominent thing. We know that about 50 percent of ADHD cases persist into adulthood. But for a long time it was like, well, this kid’s just going to outgrow this so we don’t have to worry about it in adulthood. But now we know that is not the case.
Do we know what causes ADHD?
What we find when we’re talking about the core ADHD symptoms, the extent to which this varies between people is about 80 percent heritable — about as heritable as differences in human height. The place where the environment becomes exceedingly important is in the extent to which somebody with these ADHD traits experiences impairment.
One of the well-established ways to treat ADHD is with medications. Certain stimulants like Adderall and Ritalin are pretty widely used. But they don’t work for everyone. What are some of the other ways ADHD is treated? Are they just as effective?
There are non-stimulant classes of medications: atomoxetine, various other non-stimulant medications. From the research overall, they don’t tend to be as effective as the stimulants.
The other thing is everybody’s brain is a little bit different. It would be so nice if we could just say, “Well, everyone is going to respond to this drug in this way,” but if someone doesn’t like how a stimulant makes them feel, that’s totally fine. They should talk to their doctor about trying some of these alternatives.
Anyone can benefit from general supportive counseling, but where we really see the larger effects for adult ADHD is cognitive behavioral therapy for adult ADHD, where you’re working with a mental health professional on skills that address the inattentive and impulsive symptoms.
In the biological therapy space, there is some exciting stuff going on with something called transcranial magnetic stimulation. It’s a way of stimulating the brain in certain ways that is showing signs of being able to relieve symptoms, at least for limited periods of time.
And finally, with this disorder, there have been a ton of unproven or disproven treatments out there. So I encourage buyer beware. I sit on the professional advisory board for an organization called Children and Adults with ADHD, and I would just encourage listeners to go to CHADD’s website in the National Resource Center for ADHD if they have a question about what’s the evidence for this kind of treatment.
Are you seeing an increase in people who have ADHD?
That’s such a great question, and I think to answer it, you have to draw a distinction between an increase in the number of people getting diagnosed with ADHD versus if there is a true increase in what an epidemiologist would call the prevalence of ADHD in the population.
I still can’t find solid evidence that the prevalence of the well-defined, neurobiologically related traits of ADHD are increasing. However, the thing I get concerned about as a clinician is there’s clear evidence that for certain populations, ADHD is still vastly underdiagnosed and undertreated. These populations may be the ones that are least visible to us on social media and even in advocacy spaces sometimes. These are the people that probably also have the least access to care. I want to highlight that it can simultaneously be over and underdiagnosed — depending on who you’re talking about.
I think we’ve seen a real rise in people talking about ADHD on social media, and there are even ADHD influencers. How accurate is what we’re seeing online?
I had a lot of fun looking up the very recent research studies on this that are fascinating. A couple of studies have taken the top videos on TikTok, and then had experts rate the quality of the information that is in these videos. There are only a couple studies, but they all land around that basically 50 percent of what’s on #ADHD TikTok videos is not accurate. There’s a lot of what I would call misinformation: not that people are necessarily trying to spread misinformation, but I think a lot of the content tends to communicate personal experiences. There’s nothing inherently wrong with that, but I do think there is a risk of possibly overpathologizing experiences that are just part of normal human experience.
On the other hand, it’s a tremendous opportunity for awareness for advocacy. I really think we so-called experts are really dropping the ball here. In one of the studies, almost none of these top videos were put out by people like me who study this for a living. We have got to change that.
