Attention Deficit Hyperactivity Disorder (ADHD) is characterized by problems paying attention, excessive activity, or difficulty controlling behavior which is not appropriate for a person's age. These symptoms begin by ages 6 to 12, are present for more than six months, and cause problems in at least two settings (such as at school, home, or other recreational activities). In children, problems paying attention may result in poor school performance. Although it causes impairment, particularly in modern society, many children have a good attention span for tasks they find interesting.
Current models of ADHD suggest that it is associated with functional impairments in some of the brain's neurotransmitter systems, particularly those involving dopamine and norepinephrine. The dopamine pathways and norepinephrine pathways which project to the prefrontal cortex and striatum are directly responsible for modulating executive function (cognitive control of behavior), motivation, reward perception, and motor function.
Supernanny/Jo Frost: Extreme Parental Guidance episodes featuring children with ADHD
Park Family 6-year-old Kyle has ADHD
Beck Family 9-year-old Hunter has ADHD
Goins Family 6-year-old Khalin has ADHD
Prescott Family 7-year-old Daniel has ADHD
Regan and Josh 7-year-old Regan has ADHD
Signs and symptoms
Inattention, hyperactivity (restlessness in adults), disruptive behavior, and impulsivity are common in ADHD. Academic difficulties are frequent as are problems with relationships. The symptoms can be difficult to define as it is hard to draw a line at where normal levels of inattention, hyperactivity, and impulsivity end and significant levels requiring interventions begin.
ADHD can be divided into three subtypes: predominantly inattentive, predominantly hyperactive-impulsive, and combined type.
An individual with inattention may have some or all of the following symptoms:
- Be easily distracted, miss details, forget things, and frequently switch from one activity to another
- Have difficulty maintaining focus on one task
- Become bored with a task after only a few minutes, unless doing something enjoyable
- Have difficulty focusing attention on organizing and completing a task or learning something new
- Have trouble completing or turning in homework assignments, often losing things (e.g., pencils, toys, assignments) needed to complete tasks or activities
- Does not seem to listen when spoken to
- Daydream, become easily confused, and move slowly
- Have difficulty processing information as quickly and accurately as others
- Struggle to follow instructions
- Have trouble understanding minute details
An individual with hyperactivity may have some or all of the following symptoms:
- Fidget and squirm in their seats
- Talk nonstop
- Dash around, touching or playing with anything and everything in sight
- Have trouble sitting still during dinner, school, doing homework, and story time
- Be constantly in motion
- Have difficulty doing quiet tasks or activities
These hyperactivity symptoms tend to go away with age and turn into "inner restlessness" in teens and adults with ADHD.
An individual with impulsivity may have some or all of the following symptoms:
- Be very impatient
- Blurt out inappropriate comments, show their emotions without restraint, and act without regard for consequences
- Have difficulty waiting for things they want or waiting their turns in games
- Often interrupt conversations or others' activities
People with ADHD more often have difficulties with social skills, such as social interaction and forming and maintaining friendships. This is true for all subtypes. About half of children and adolescents with ADHD experience social rejection by their peers compared to 10–15% of non-ADHD children and adolescents.
Difficulties managing anger are more common in children with ADHD as are poor handwriting and delays in speech, language and motor development.
In children ADHD occurs with other disorders about ⅔ of the time. Some commonly associated conditions include:
- Learning disabilities have been found to occur in about 20–30% of children with ADHD. Learning disabilities can include developmental speech and language disorders and academic skills disorders. ADHD, however, is not considered a learning disability, but it very frequently causes academic difficulties.
- Tourette's Syndrome has been found to occur more commonly in the ADHD population.
- Oppositional Defiance Disorder (ODD) and Conduct Disorder (CD), which occur with ADHD in about 50% and 20% of cases respectively. They are characterized by antisocial behaviors such as stubbornness, aggression, frequent temper tantrums, deceitfulness, lying, and stealing.
- Primary disorder of vigilance, which is characterized by poor attention and concentration, as well as difficulties staying awake. These children tend to fidget, yawn and stretch and appear to be hyperactive in order to remain alert and active.
- Mood disorders (especially Bipolar Disorder and Manic Depressive disorder). Boys diagnosed with the combined ADHD subtype are more likely to have a mood disorder.
- Anxiety disorders have been found to occur more commonly in the ADHD population.
- Obsessive-Compulsive Disorder (OCD) can co-occur with ADHD and shares many of its characteristics.
- Substance use disorders. Adolescents and adults with ADHD are at increased risk of developing a substance use problem. The reason for this may be an altered reward pathway in the brains of ADHD individuals.
- Restless legs syndrome has been found to be more common in those with ADHD and is often due to iron deficiency anaemia.
- Sleep disorders such as Sleep Apnea and ADHD commonly co-exist. They can also occur as a side effect of medications used to treat ADHD.
The cause of most cases of ADHD is unknown; however, it is believed to involve interactions between genetic and environmental factors. Certain cases are related to previous infection of or trauma to the brain.
Twin studies indicate that the disorder is often inherited from one's parents with genetics determining about 75% of cases.
Environmental factors are believed to play a lesser role. Alcohol intake during pregnancy can cause fetal alcohol spectrum disorders which can include ADHD or symptoms like it. Exposure to tobacco smoke during pregnancy can cause problems with central nervous system development and can increase the risk of ADHD. Children exposed to lead, even low levels, or polychlorinated biphenyls may develop problems which resemble ADHD and fulfill the diagnosis. Exposure to the organophosphate insecticides chlorpyrifos and dialkyl phosphate is associated with an increased risk; however, the evidence is not conclusive.
Very low birth weight, premature birth and early adversity also increase the risk as do infections during pregnancy, at birth, and in early childhood. These infections include, among others, various viruses (measles, varicella, rubella, enterovirus and streptococcal bacterial infection. At least 30% of children with a traumatic brain injury later develop ADHD and about 5% of cases are due to brain damage.
Some children may react negatively to food dyes or preservatives. It is possible that certain food coloring may act as a trigger in those who are genetically predisposed but the evidence is weak. In a minority of children, food intolerances, food allergies, or both may trigger or worsen symptoms.
The diagnosis of ADHD can represent family dysfunction or a poor educational system rather than an individual problem. Behavior typical of ADHD occurs more commonly in children who have experienced violence and emotional abuse.
Per social construction theory it is societies that determine the boundary between normal and abnormal behavior. Members of society, including physicians, parents, and teachers, determine which diagnostic criteria are used and, thus, the number of people affected. This leads to the current situation where the DSM-IV arrives at levels of ADHD three to four times higher than those obtained with the ICD-10. Thomas Szasz, a supporter of this theory, has argued that ADHD was "invented and not discovered.
The management of ADHD typically involves counseling or medications either alone or in combination. While treatment may improve long-term outcomes, it does not get rid of negative outcomes entirely.
There is good evidence for the use of behavioral therapies in ADHD and they are the recommended first line treatment in those who have mild symptoms or are preschool-aged. Psychological therapies used include: psychoeducational input, behavior therapy, cognitive behavioral therapy (CBT), interpersonal psychotherapy, family therapy, school-based interventions, social skills training, behavioral peer intervention, organization training, parent management training, and neurofeedback. Behavior modification and neurofeedback have the best support.
Regular physical exercise, particularly aerobic exercise, is an effective add on treatment for ADHD, although the best type and intensity is not currently known. In particular, physical exercise has been shown to result in better behavior and motor abilities without causing any side effects.
Medications used include stimulants, atomoxetine, alpha-2 adrenergic receptor agonists, and sometimes antidepressants.
Stimulant medications are the pharmaceutical treatment of choice. They have at least some effect in the short term in about 80% of people. Methylphenidate appears to improve symptoms as reported by teachers and parents.
There are a number of non-stimulant medications, such as atomoxetine, bupropion, guanfacine, and clonidine that may be used as alternatives. There are no good studies comparing the various medications; however, they appear more or less equal with respect to side effects. Stimulants appear to improve academic performance while atomoxetine does not. There is little evidence on their effects on social behaviors.
Medications are not recommended for preschool children, as the long-term effects in this age group are not known.
Dietary modifications may be of some benefit. Tentative evidence supports free fatty acids supplementation and reduced exposure to food coloring. Removing food coloring may only benefit those people with food intolerances. Removing other foods from the diet is controversial.