Attention deficit hyperactivity disorder (ADHD) is one of the disorders of greater occurrence in childhood and adolescence. Studies in many countries show that ADHD is present in 5 to 10% of the school-aged children.

Behavior typical of children and adolescents with ADHD include difficulty to focus their attention on a single object, they are easily distracted, appear not to listen when spoken to, and daydream. They may not finish their homework, show great difficulty organizing themselves, and frequently lose school material, keys, money, or toys.

The child may show to be restless, not being able to stay seated, leaves his seat in the classroom or from the dining table at home. He always seems to be agitated, talks excessively, and hardly ever plays quietly. He is always screaming. Patients with this diagnosis have poor academic and social performance because it is difficult for them to be organized, to keep focus in the classroom, and to do school work, or to remain seated and quiet.

The causes for ADHD still have not been established. Studies indicate it is of multifactorial origin, where genetics is the most important factor.

Many of the children with ADHD have relatives (parents, uncles, grandparents, brothers and sisters) with the same diagnosis. Incidence can reach up to ten times more in families with children with ADHD when compared to the population in general. Some studies associate the genetic heritage linked to the genes of the receptor and transporter of dopamine, a substance that along with other substances enable the communication between neurons. Children of hyperactive parents have greater chances of having the disorder, as well as a brother or sister of hyperactive children have twice as much chances of presenting the diagnosis in comparison to siblings without the disorder.

Studies have already shown that the brains of children with ADHD function differently from children without the disorder. These children present an imbalance of chemical substances that help the brain control behavior. Neuropsychological studies suggest alterations in the prefrontal cortex and subcortex structures of the brain. Poor results in tests measuring attention, learning, and the following of instructions also suggest a deficit in inhibitory behavior and in executive functions (involved in processes such as planning, cognitive flexibility, abstract thinking, rule acquisition, initiating appropriate actions and inhibiting inappropriate actions, and selecting relevant sensory information). Neuroimaging shows decreased blood flow in the brain and metabolic rates in the frontal lobe regions of children with ADHD.

Two neurotransmitters, dopamine and noradrenaline, had their activity diminished in the prefrontal cortex of the brain, which is a highly important area responsible for attention control. The stimulant medications used for treatment, increase these substances, improving the activity of these neurotransmitters in these regions of the brain and facilitating attention control.

Complications during pregnancy or delivery which cause damage to the baby’s brain are hypothetically related to ADHD, as traumas, intoxications, and infections. However, it is worth mentioning that such complications are related to diseases in general and not specifically to ADHD.

How is diagnosis done?

ADHD diagnosis is essentially clinical. There are no laboratory or image screenings. ADHD investigation takes detailed clinical studies through assessments with the parents, the child, and the school. Standardized tests for the parents and teachers can be used. The assessment with the parents must include a detailed history of the child or adolescent’s development, all the way back from the mother’s pregnancy to the current days.

Inattention Symptoms

• Does not pay attention to details or makes careless mistakes in school activities, at work, and other activities.
• Has difficulty sustaining attention in tasks or recreational activities.
• Seems to not listen when spoken to.
• Does not follow instructions and fails to finish schoolwork, home chores or professional responsibilities (not due to oppositional behavior or inability to understand instructions).
• Has trouble organizing tasks and activities.
• Avoids and is reluctant to engage in tasks that require sustained mental effort (such as schoolwork or home chores).
• Loses things that are necessary for accomplishing tasks or activities (for example toys, schoolwork, pencil, books, or other material).
• Gets easily distracted
• Is forgetful in daily activities

Hyperactivity/impulsiveness symptoms

• Fidgetiness with hands or feet or squirming when seated
• Leaves his seat in the classroom or in other situations in which remaining seated is expected.
• Inappropriate running and climbing (in adolescence or adulthood, this may be limited to subjective feelings of restlessness)
• Difficulty playing or engaging in leisure activities quietly
• Seems to be constantly on the go
• Talks excessively
• Blurts out answers before questions have been completed
• Difficulty waiting for his turn
• Inappropriate interruptions or interference into conversations (such as, butting in when others are talking or playing)

Impairment must be evident in social, academic or occupational functioning of the child or adolescent. No impairment, no disorder diagnosis.

What are the consequences of ADHD?