Attention Deficit Hyperactivity Disorder

ADHD affects about 5% of children worldwide, regardless of culture. It is more than 2-fold more
common in boys and over half of children with ADHD continue to suffer from this disorder as adults.
Diagnosis of ADHD is based on ‘hyperactivity’ (e.g. inability to sit still, lack of organisation),
‘inattentiveness’ (forgetful, poor concentration, abandoning tasks before completion) and
‘impulsivity’ (acting without considering the risks, interrupting). These three features must be
evident before the age of seven; they must be present in at least two settings (e.g., school,
workplace or home); and they must last for at least 6 months. The expression of ADHD by patients is
described as either: Predominantly Inattentive (more common in girls), Predominantly Hyperactive /
Impulsive (more common in boys) or Combined type (Inattentive and hyperactivity/impulsive), but
these are not fixed subtypes and they can change with time in individual patients. For instance,
hyperactivity usually disappears as children approach adulthood, although a feeling of ‘restlessness’
persists.