The Preschool ADHD Treatment Study (PATS)
Another problem in diagnosing infants, toddlers, and preschoolers with ADHD is how to effectively treat symptoms. PATS, a study conducted by the National Institute of Mental Health (NIMH) in 2006, was the first long-term study designed to look at the effectiveness of treating preschoolers with ADHD with behavior therapy and/or methylphenidate. The study looked at 300 preschoolers with severe ADHD, including a history of preschool expulsion and rejection by peers.
In the first stage of the study, the preschoolers and their parents took part in a ten-week behavior therapy course. Parents were trained in behavior modification techniques, including using consistent praise, ignoring negative behavior, and using timeouts. More than a third of the children responded so favorably to behavior modification that they did not go on to the medication phase of the study.
Children with extreme ADHD symptoms who did not improve with behavior therapy participated in a double-blind study comparing low doses of methylphenidate (Ritalin) with a placebo. Methylphenidate treatment resulted in a significant reduction in ADHD symptoms, as measured by standard rating forms and observations at home and at school.
However, the study reported that the children's ability to tolerate the drugs was less than expected. Eleven percent of the children ultimately stopped treatment, despite improvements in ADHD symptoms, because of moderate to severe side effects. These included a reduction in appetite, an increase in insomnia and anxiety, emotional outbursts, repetitive behaviors and thoughts, and irritability. Preschoolers appeared to be more susceptible to side effects than children in elementary school.
One adverse effect of stimulant medication is that it appears to slow the growth rate of preschoolers. Children who participated in the PATS study and took stimulant drugs grew a half inch less and weighed three pounds less than normal growth rates.
The Medication Controversy
Experts remain divided on whether preschool children should take drugs to control ADHD symptoms. Some feel that the methodology for diagnosing infants and toddlers is unreliable, as is the effect of drugs on a developing brain, and that more research is needed before infants, toddlers, and preschoolers are given medication for ADHD. Others argue that because the PATS study showed that some young children with ADHD benefited from ADHD medication, those with severe ADHD should be treated to control out-of-control behavior.