Attention-Deficit Hyperactivity Disorder (ADHD)

What Is It?

Attention-deficit hyperactivity disorder (ADHD), usually first diagnosed in childhood, can appear in a variety of forms and has many possible causes. People with ADHD probably have an underlying genetic vulnerability to developing it, but the severity of the problem is also influenced by the environment. Conflict and stress tend to make it worse.

The main features of this disorder are found in its name. Attention problems include daydreaming, difficulty focusing and being easily distracted. Hyperactivity refers to fidgeting or restlessness. A person with the disorder may be disruptive or impulsive, may have trouble in relationships and may be accident-prone. Hyperactivity and impulsiveness often improve as a person matures, but attention problems tend to last into adulthood.

ADHD is the most common problem seen in outpatient child and adolescent mental health settings. It is estimated that ADHD affects between 5% and 10% of school-aged children. Boys are more often diagnosed with ADHD than girls. Studies suggest that the number of ADHD diagnoses has risen significantly over the years. But whether more people have the disorder or whether it is just being diagnosed more often is not clear. The definition of the disorder has changed over the past several decades and will continue to develop as the experts explain more about the biology behind it.

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