The largest study of its kind reveals that one-third of children with ADHD still have the condition as adults and are highly susceptible to other psychiatric disorders.

Attention deficit-hyperactivity disorder, or ADHD, is typically characterized by a child’s inability to pay attention in class, but new research is poised to change our perspective on this all-too-common disorder.

A third of children diagnosed with ADHD still had ADHD symptoms as adults, and they were more likely than their peers to have another psychiatric disorder, to be arrested, or to commit suicide, according to the largest study to date on the subject.

“We suffer from the misconception that ADHD is just an annoying childhood disorder that’s over-treated,” lead investigator William Barbaresi, MD, said in a press release. “This couldn’t be further from the truth. We need to have a chronic disease approach to ADHD as we do for diabetes. The system of care has to be designed for the long haul.”

Researchers from Boston Children’s Hospital and the Mayo Clinic conducted the first population-based study of ADHD that followed 5,718 children from childhood into adulthood. Of those children, 367 were diagnosed with ADHD.

Among their findings, published in the journal Pediatrics,researchers discovered that:

  • Twenty-nine percent of the children with ADHD still had symptoms as adults, and 81 percent of these adults had at least one other psychiatric disorder.
  • The most common co-occurring disorders were substance abuse, antisocial personality disorder, hypo-manic episodes, anxiety, and major depression. (Only 35 percent of children without ADHD experienced these conditions as adults.)
  • Seven of the 367 children with ADHD had died when researchers conducted a follow-up, three of them from suicide, which was a higher suicide rate than in the control group.
  • Ten children with ADHD, or 2.7 percent, were incarcerated at the time of recruitment for the study.

“Only 37.5 percent of the children we contacted as adults were free of these really worrisome outcomes,” Barbaresi said. “That’s a sobering statistic that speaks to the need to greatly improve the long-term treatment of children with ADHD and provide a mechanism for treating them as adults.”

Researchers did note one issue with their sample population: the children in the study were largely middle class, with access to education and healthcare—including at the world-renowned Mayo Clinic.

“One can argue that this is potentially a best-case scenario,” Barbaresi said. “Outcomes could be worse in socioeconomically challenged populations.”

About three quarters of the 367 children with ADHD in the study population received treatment. It is possible that children with less-than-ideal treatment options would not fare as well.

The researchers said that parents of children with ADHD should ensure their children receive the best care possible, and that care should continue into adolescence.

They also said that children with ADHD should be evaluated for learning disabilities and associated conditions, as well as educated about substance abuse, depression, and anxiety.

If left untreated—or under-treated—ADHD can lead to a number of problems.

As the researchers noted, long-term complications of ADHD include:

  • difficulty in school, including trouble with reading, spelling, math, and writing
  • trouble in social situations and personal relationships
  • engaging in risky behaviors, such as erratic driving and drug use
  • obsessive compulsive disorder (OCD)
  • borderline personality disorder (BPD)

However, certain traits associated with ADHD, such as hyperfocus, can be advantageous, and famous people throughout history—including Bill Gates, Walt Disney, and five U.S. presidents—have used these traits to change society for the better.

Though ADHD is a chronic and debilitating condition for some, it has been linked to a higher incidence of leadership, athletic ability, and creativity. In the case of ADHD, lifelong management is truly the key.