Preschoolers can be inattentive or hyperactive even on the best of days, so it can be difficult to accurately diagnose attention-deficit hyperactivity disorder. But a growing body of research has shown that early treatment can help struggling children and frazzled parents.

The diagnosis of young children with ADHD is “very contentious” since there is a blurry line between common developmental changes and symptoms of the mental disorder, says ADHD researcher Stephen Hinshaw, PhD, chair of the psychology department at the University of California at Berkeley. “The symptoms for ADHD are very ubiquitous and very age-relevant,” he says. “It’s hard to know if you’re seeing the signs of a disorder or just the signs of a young kid.”

Hinshaw and some other researchers believe ADHD can be reliably diagnosed in children as young as 3 after thorough evaluations. In one study of school-age children, mothers reported that symptoms of ADHD appeared at or before age 4 in two-thirds of the children (Journal of Developmental & Behavioral Pediatrics, Vol. 23, No. 1).

Researchers disagree about whether ADHD is overdiagnosed, which may lead to unnecessary medication of healthy children. There is a tendency to overdiagnose young children with ADHD because of a lack of understanding about normative development in toddlerhood and the early preschool years, says Susan Campbell, PhD, a psychology professor at the University of Pittsburgh who has researched ADHD for more than three decades. “The only reason to diagnose a young child is to access appropriate services to help the child and family,” she says. “Sometimes the earlier the better.”

Overall, more children of all ages are being diagnosed with ADHD since there is greater awareness of the disorder and improvements in treatment, says Russell Barkley, PhD, a psychologist and professor at the Medical University of South Carolina who studies ADHD. Some inaccurate media reports have fueled a public misperception that ADHD is overdiagnosed, Barkley says. But only 20 percent of children with ADHD received any treatment in the 1960s and ’70s, compared with roughly 70 percent to 80 percent today, he says.

“The rise in diagnosis is not bad news. It’s good news,” Barkley says. “Frankly, we were doing an awful job 20 or 30 years ago.”

Medication issues

Often the first line of treatment for ADHD in school-age children is medication with stimulants, which have been found to be generally safe and effective. But drugs have less positive results for preschoolers. “I’m very opposed to the use of medication with young children because we don’t really know the implications for brain development,” Campbell says.

Approximately 4 million children — or 8 percent of all minors in the United States — have been diagnosed with ADHD, and more than half of them take prescription drugs. Methylphenidate hydrochloride (Ritalin) is the most commonly prescribed medication, but its use in children under 6 years old hasn’t been approved by the Food and Drug Administration, which cites a lack of research for this age group. As a result, doctors are prescribing methylphenidate off label for preschoolers with ADHD.

The most comprehensive study on medication of preschoolers with ADHD showed mixed results for 3- to 5-year-old children. Funded by the National Institute of Mental Health, the multisite Preschool ADHD Treatment Study enrolled 303 preschoolers and their parents in a 10-week behavioral therapy course. Children with severe symptoms who didn’t respond to therapy were given low doses of methylphenidate or a placebo. The medicated children showed a marked reduction in symptoms compared with the placebo group, according to the study results published in 2006.

More troublesome, though, was the fact that almost a third of parents reported that their medicated children experienced moderate to severe side effects, including weight loss, insomnia, loss of appetite, emotional outbursts and anxiety. Eleven percent of the preschoolers dropped out of the study because of their reactions to methylphenidate. During the study, the medicated children also grew about half an inch less in height and weighed about three pounds less than expected based on average growth rates (Journal of the American Academy of Child & Adolescent Psychiatry, Vol. 45, No. 11).

“The bottom line to me is for this age group, I don’t believe stimulant medication is a first-line treatment,” says George DuPaul, PhD, a professor of school psychology at Lehigh University who studies ADHD.

Embracing other methods

Parental training and school-based interventions can be effective in treating preschoolers with ADHD, DuPaul says. His book, “Young Children With ADHD: Early Identification and Intervention” (APA, 2011), co-written with Lehigh University colleague Lee Kern, PhD, describes one of their studies of nondrug interventions with 135 preschoolers with ADHD.

Parents were given 20 training sessions on behavior problems, basic math and language skills, and child safety since children with ADHD often suffer accidental injuries because of their hyperactivity and impulsivity. One group of children also received individual assessments in the home and at preschool or day care. Both groups of children showed marked improvements in ADHD symptoms, although there was no significant advantage for the children with individual assessments (School Psychology Review, Vol. 36, No. 2). One limitation of the study was the lack of a control group because of ethical considerations about providing no treatment.

While older children can sometimes be taught to manage their ADHD symptoms, the training of preschool children has been more difficult, in part because cognitive-behavioral therapy doesn’t work, Barkley says. Preschoolers with ADHD are delayed in communication skills, and language hasn’t been internalized yet, so they can’t use mental instructions or self-monitoring to change their behavior.

“It failed so we abandoned that after multiple studies found it had little or no influence,” Barkley says.

But some behavioral management techniques are effective, including a token reward system and praise to provide extra motivation for preschoolers with ADHD, Barkley says. Teachers can seat children with ADHD near the teacher’s desk and provide detailed explanations of class rules and disciplinary procedures, such as time-out or loss of tokens. Frequent class breaks and shorter work assignments also can help maintain children’s attention and reduce outbursts.

Symptoms of ADHD can be exacerbated in children by impulsive parents who also have ADHD, Campbell says. Parents who are quick to anger and who frequently use physical punishment also can be detrimental. “There is going to be an interaction between the genetic risk and the support or lack of parental support the child has,” she says.

Looking ahead

As the diagnosis of preschoolers with ADHD has increased, so have questions about the lack of age-specific symptoms in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. “It’s crazy to me that we use the same criteria for a 3-year-old as we do for a 35-year-old,” DuPaul says.

Scheduled for publication in 2013, the fifth DSM edition should require a greater number of symptoms for diagnosing young children with ADHD and more age-specific symptoms instead of generic descriptions such as fidgeting or running around and climbing, DuPaul says. “How do we apply that to a 17-year-old kid in a high school classroom?” he says. “They don’t run about and climb on things.”

Despite the risks, early identification and treatment of ADHD can provide substantial benefits for children and their families, Campbell says. “It can help so that when the child gets to the first grade, he isn’t the only child no one else wants to play with and no teachers want in their class,” she says.

Brendan L. Smith is a writer in Washington, D.C.