Preschool Attention Deficit Disorder

New studies show that both drugs and parent training can be effective.

Attention-deficit/hyperactivity disorder (ADHD) is no longer just for schoolchildren. As we have been learning, it can be a lifelong disorder: the symptoms of impulsiveness, inattentiveness, and hyperactivity may occur at any age. At one end of the age scale, adult ADHD is taken increasingly seriously. At the other end, ADHD has already become the most common diagnosis for children ages 3–5 who are referred to mental health professionals. Researchers have begun to explore more systematically the use of drugs and other treatments for these preschoolers.

Applying to adults a diagnosis originally derived from the symptoms of school-age children has presented some problems; different problems arise when the diagnosis is used for younger children. It's difficult enough to define standards of hyperactivity, impulsiveness, and inattentiveness for schoolchildren. A three- or four-year-old, not spending most of the day in a classroom, is not facing the same demands for paying attention and following rules. At that young age, being fidgety or inattentive could be considered normal. To show that something more is involved than kids being kids, clinicians and researchers compare a child with others the same age to determine whether the symptoms are, as the American Psychiatric Association's diagnostic manual says, severe, frequent, persistent, and "inconsistent with developmental level."

Studies have found that ADHD symptoms under age 6 are strikingly similar to those found in older children — including the high rate of depression and oppositional defiant disorder. These children are not just rambunctious. They seem unable to wait their turn or think before acting. They may jump off playground slides, play with matches despite repeated warnings, climb into medicine cabinets, rush into traffic, and pull down objects from the shelves of stores. They are noisy and constantly interrupt other children and adults. They can sow chaos at home or in day care.

For a diagnosis of ADHD, the American Academy of Child and Adolescent Psychiatry recommends — at all ages — a general psychiatric evaluation, interviews with parents, information from schoolteachers or preschool teachers, and monitoring of the child in several settings. It's important to rule out problems arising from other psychiatric disorders, developmental disorders, medical illnesses, and, especially, the situation at home. For preschool children, the Academy specifically recommends "suspicion" of parental abuse or neglect as a possible source of ADHD-like symptoms.

Drug Treatment

Stimulant drugs, the standard treatment for ADHD in school-age children and to some degree in adults, are increasingly prescribed for younger children as well. It's estimated that 1% of preschool children have been given stimulants — chiefly methylphenidate (Ritalin and others), although the FDA has not approved it for children under age 6.

Until recently there were only ten brief studies of methylphenidate use in preschoolers, six of which found that it was effective. The NIMH-funded Preschool ADHD Treatment Study (PATS) is the first large rigorous controlled trial of the drug in children ages 3–5. Results of the 16-month study were published in 2006 in the Journal of the American Academy of Child and Adolescent Psychiatry.

The 303 children who entered the study had shown symptoms of ADHD for at least nine months in several different settings, such as home and day care. And the resulting problems were serious — for example, parents said that the child had been expelled from preschool or that they were afraid to take him (or occasionally her) into public places. The researchers took care to exclude children with adjustment disorders and psychiatric or developmental disorders such as depression, anxiety, and autism.

The study began with 10 weeks of parent training as an alternative to drugs. A week of safety testing followed, then a period of five weeks in which the most effective dose was determined for each child. Some dropped out at each of these stages. Eventually 165 entered a classical double-blind clinical trial. All of them had responded to the drug and had not responded to a placebo at earlier stages. They were divided into two groups and, for four weeks, half of them were given the dose of the drug to which they had previously responded, while the other half took a placebo.

The drug was more effective than the placebo, although not as effective as it is in school-age children. It provided more overall relief of symptoms than a placebo, but not more "excellent" responses (the difference, 22% versus 13%, was not significant). The average dose was half that given to older children. Nearly a third of the children dropped out during this phase, mainly because their behavior was deteriorating — 45% of those taking the placebo and 15% of those taking the drug.

After that, any child who had originally entered the study, including those who had dropped out before the double-blind clinical trial, could go on to take the drug on an open-label basis. Of that group, 140 chose to; 95 continued to take it for at least 10 more months.

Drug Side Effects

According to spontaneous reports from parents and symptom checklists, several symptoms occurred more often in children taking the drugs than in those taking a placebo — appetite loss, weight loss, and disturbed sleep. The researchers believe these problems can be managed by lowering the dose and providing a snack at bedtime, when the effect of the drug is wearing off. About 10% of children stopped taking the drug during the study because of side effects.

More serious adverse reactions — those presenting a medical threat or seriously interfering with the child's life — were rare. Eight such reactions occurred during the study, but only one, a seizure, was regarded as possibly related to use of the drug.

In 2006, after reports of sudden cardiac death in children taking stimulants, the FDA ordered manufacturers to revise the labels of all drugs used in the treatment of ADHD to warn about cardiovascular risks. But in PATS, such risks were not apparent. Methylphenidate had no more effect on heart rate and blood pressure than the placebo.

Despite their encouraging findings, the authors note that by FDA standards, the number of participants in the study was too small to declare methylphenidate definitely safe for preschool children.

The most significant long-term side effect involved stunted growth. Children who took methylphenidate for a year or more grew by an average of ½ inch and 3 pounds, numbers that were respectively 25% and 55% less than expected for their age. When the study began, incidentally, these children had been taller than average by ? inch and heavier than average by 4 pounds, which suggests early physical maturity. The researchers are following up as the study continues.

The Parent Training Alternative

Particularly because of concern about long-term effects on the developing brain, there are misgivings about prescribing drugs for very young children. The aim of parent training is to reduce hyperactive and impulsive behavior by changing the way parents respond to it. They are shown how to set appropriate limits and use moderate rewards and punishments. Parent training might be especially helpful for preschool children, because it can work for them before attitudes harden and the expectation of failure becomes self-fulfilling for the child, for parents, and eventually for teachers and others.

In one study, behavioral parent training was combined with an effort to encourage more constructive interactions between parents and children with ADHD. Children ages four to six who were randomly assigned to this treatment for two months had a better outcome than those who received only general counseling. The training was about as effective as methylphenidate, but it worked only when conducted by specialists with experience in behavior therapy — and it is not known how long the improvement lasts.

Too Much or Too Little?

ADHD has always been a controversial diagnosis, and it does not become less so when applied to younger and younger children. Critics believe that the diagnosis is overused and drugs are oversold as a solution. The growth of preschool programs and day care might be making excessive demands on young children for self-control and obedience to rules. But others say that ADHD is not diagnosed as often as it should be. The only two studies conducted in pediatric clinics found that it was not identified in preschool children even when their parents were worried about the child's behavior. One study found that only 23% of preschool children with possible ADHD had been referred for mental health evaluation.

Given the doubts and disputes, it is probably best to follow the recommendations of the American Academy of Child and Adolescent Psychiatry, which were also adopted in the PATS study: Be slow to make the diagnosis, and consider parent training and specialized day care before resorting to stimulant drugs.