Why have rates of ADHD in kids gotten so high?

ADHD cases have risen considerably in the U.S.

As of 2022, around 1 in 9 children had been diagnosed with attention-deficit/hyperactivity disorder at some point in their lifetimes, according to a study published Wednesday. Roughly 6.5 million children ages 3 to 17 had ADHD that year — up from 5.4 million in 2016.

The study’s lead author, Melissa Danielson, a statistician at the Centers for Disease Control and Prevention, said there are two main reasons for the trend. First, doctors, parents, teachers and kids are becoming more aware of ADHD symptoms, making cases easier to identify. Second, because more treatments are available these days, doctors have more reason to test and diagnose children.

“There’s more providers that are comfortable with making those diagnoses and treating ADHD, which can allow for children to be helped by different medications or behavior therapy or school services. So since there are more opportunities for these kids to be helped, I think there’s more incentive to get that kind of diagnosis,” she said.

Because the study results suggest that more children are being screened, she added, it “could be a positive finding.”

A third factor in the trend, Danielson said, may have been the Covid-19 pandemic, which could have aggravated ADHD symptoms or allowed parents to observe their children more closely.

The estimates in her study, published in the Journal of Clinical Child & Adolescent Psychology, were based on more than 45,000 responses to the 2022 National Survey of Children’s Health. 

Mental health professionals who diagnose and treat ADHD said the data is consistent with their experiences.

“This is something that we’re seeing every day. We’re having more and more families coming in and patients wondering if they do have ADHD,” said Dr. Willough Jenkins, a psychiatrist at Rady Children’s Hospital-San Diego who was not involved in the study.

In particular, Jenkins said, doctors have gotten better at recognizing the disorder in girls and older children.

“Before, it was thought very much ADHD was an illness of just young, hyperactive boys,” she said. “In the last 15, 10 years, that’s really quite changed. And even within the last five years, we’re seeing a lot of improved diagnosis.” 

ADHD is one of the most commonly diagnosed neurodevelopmental disorders in children and teenagers. Cases have been rising for several decades as awareness has increased. The disorder is often characterized by difficulty concentrating, sitting still or exercising self-control. 

Danielson said younger children with ADHD tend to be more hyperactive or impulsive, while in adolescence, the disorder tends to shift more toward inattention — behaviors like daydreaming, hyperfocusing or having trouble finishing tasks.

Other mental health experts agree that the pandemic most likely accelerated ADHD diagnoses.

Thomas Power, director of the Center for Management of ADHD at Children’s Hospital of Philadelphia, said the stress of remote learning, social isolation, family health scares and disrupted routines may have worsened kids’ symptoms, leading them to become more visible.

“Particularly for children who had some mild attention difficulties, learning in that type of context would be that much more challenging and could be enough to trigger an attention-deficit disorder,” he said.

As parents spent more time at home, they may also have noticed their children struggling, said Yamalis Diaz, a child and adolescent psychologist at NYU Langone’s Child Study Center. 

“It gave parents a prolonged observation period of their child trying to focus and trying to do academic work,” Diaz said. “Parents are now observing, ‘My gosh, my child interrupts me 50 times a day just to do one task.’”

But Jenkins said there may have been a small uptick in misdiagnoses during the pandemic, because rates of depression and anxiety increased during that time, and the symptoms can overlap.

“People might not have realized that anxiety and depression could be a reason why you can’t pay attention,’” she said.

Discussions of ADHD on social media rose during the pandemic, as well, according to a 2022 study. Danielson said that may have led some older children to self-diagnose.

“As kids and adolescents are spending more time on social media and learning more about ADHD, they might see it a little bit more in themselves,” Danielson said. 

Excessive screen time, however, has been shown to increase the risk of ADHD, according to some past research — so it may be another, though lesser, reason for the trend, Power said.

“There’s been certainly a lot of attention recently on the downside of a lot of involvement of children in social media and in video games, so I think that those may be contributory factors,” he said.

Jenkins highlighted one other important contributor to ADHD rates: changes in diagnostic guidelines from the American Psychiatric Association. 

Until 2013, doctors would not diagnose a child with both autism and ADHD, because of concerns that attention issues related to autism would be confused with ADHD. A child also needed to have ADHD symptoms before age 7 to be diagnosed. But for the last decade-plus, an updated diagnostic manual has said children can be diagnosed with ADHD if they have autism, as well as if their symptoms appeared before age 12.

Diaz said expanding the criteria most likely helped more kids access treatment. 

“The reason for the diagnosis isn’t simply to label kids,” she said. “It really is to identify where there might be some challenges that we can actually rectify and course-correct.”

Doctors usually recommend behavior therapy for younger children with ADHD, while older children may get a combination of behavior therapy and medication.

But according to the new study, 30% of children with ADHD in 2022 did not receive behavior therapy or medication, compared with 23% in 2016.

Danielson said some kids receive behavior therapy in school, so virtual learning during the pandemic may have cut off access. The Food and Drug Administration also reported a shortage of ADHD medications starting in 2022 — an issue that continues to some degree today, though some of the shortages were resolved recently, the FDA said.

Some drugmakers have attributed the shortage, in part, to high demand due to rising ADHD diagnoses.

Diaz said it can still be hard to find appointments with doctors who treat ADHD.

“Even in places where the treatment options are saturated, like New York City, there are waiting lists everywhere,” she said. “It’s possible that parents would have wanted to or tried and just could not get access to good treatment.”

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