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Attention Deficit Hyperactivity Disorder (ADHD): Children at Risk

Children at Risk

Three to five percent of all children have this disorder, with some estimates as high as 15%. That means that more than a million children in the U.S. have ADHD.


Although signs of ADHD may be apparent during the preschool years, most families seek help when the child starts is in elementary school and the child's behavior interferes with his adjustment and learning.

ADHD is a chronic, not an episodic, illness. It generally starts early and may get worse over time as the demands on the child increase. Early and mid-adolescence are particularly difficult times for children with ADHD. In some children the symptoms diminish or disappear during late adolescence. They may depend on medication to function to their capacity in academic and social situations. About half of the children with this disorder may outgrow the symptoms by early adulthood; the other half learn strategies for getting work done and getting along with other people. In a small proportion, the disorder will persist through the rest of their lives.


Children with ADHD is more prevalent in boys than girls, with the ratio estimated at anywhere from 4:1 to 9:1. (The ratio may shift as we come to learn more about how the specific manifestations of ADHD differ between boys and girls.)

Family History

ADHD is not the fault of the parent or the child. Children are born with a vulnerability to this disorder. There is evidence that ADHD is genetic; parents of children diagnosed with ADHD showed symptoms associated with the disorder when they were younger. Among twins, ADHD is more likely to occur in those who are identical than among those who are fraternal.