Attention-deficit/hyperactivity disorder (ADHD) is a brain disorder marked by an ongoing pattern of inattention and/or hyperactivity-impulsivity that interferes with functioning or development.
ADHD has three subtypes
- Most symptoms (six or more) are in the hyperactivity-impulsivity categories.
- Fewer than six symptoms of inattention are present, although inattention may still be present to some degree.
- The majority of symptoms (six or more) are in the inattention category and fewer than six symptoms of hyperactivity-impulsivity are present, although hyperactivity-impulsivity may still be present to some degree.
- Children with this subtype are less likely to act out or have difficulties getting along with other children. They may sit quietly, but they are not paying attention to what they are doing. Therefore, the child may be overlooked, and parents and teachers may not notice that he or she has ADHD.
Combined hyperactive-impulsive and inattentive
- Six or more symptoms of inattention and six or more symptoms of hyperactivity-impulsivity are present.
- Most children have the combined type of ADHD.
A short history of ADHD
In 1980, DSM III defines “Attention Deficit Disorder, with or without hyperactivity”, thus distinguishing between ADD and ADHD, and listing “inattention, impulsivity and hyperactivity” as essential features. Virginia Douglas investigates specific disabilities of hyperactive children in 1970, suggesting that a core group of symptoms involving inability to sustain attention and to control impulsivity can account for most of the deficits.
ADHD prevalence rates may vary depending on several factors:
- Age – ADHD can affect people of all ages, and ADHD prevalence rates are known to vary between children, adolescents and adults
- Gender – a higher prevalence of ADHD is often reported in males
- Presentation of ADHD – the predominantly inattentive presentation of ADHD is considered most prevalent in school-age children, adolescents and adults
- ADHD is often present alongside psychiatric comorbidities such as oppositional defiant disorder, conduct disorder, anxiety disorder, personality disorders and depression, which may further complicate understanding of true prevalence rates.
Reported ADHD prevalence rates vary worldwide, mainly due to methodological differences between studies. A meta-analysis of studies (n=102) of children and adolescents diagnosed with ADHD found that the prevalence of ADHD in individuals aged ≤18 years varied between countries worldwide; the prevalence estimate for Europe specifically was just under 5%
The cause(s) and risk factors for ADHD are unknown, but current research shows that genetics plays an important role. In addition to genetics, there are other possible causes and risk factors including:
- Brain injury
- Exposure to environmental (e.g., lead) during pregnancy or at a young age
- Alcohol and tobacco use during pregnancy
- Premature delivery
- Low birth weight
Signs and symptoms
- Inattention means a person wanders off task, lacks persistence, has difficulty sustaining focus, and is disorganized;
The main signs of inattentiveness are:
- Short attention span and being easily distracted
- Making careless mistakes – for example, in schoolwork
- Appearing forgetful or losing things
- Being unable to stick at tasks that are tedious or time-consuming
- Appearing to be unable to listen to or carry out instructions
- Constantly changing activity or task
- Having difficulty organizing tasks
- Hyperactivity means a person seems to move about constantly, including in situations in which it is not appropriate; or excessively fidgets, taps, or talks.
The main signs of hyperactivity and impulsiveness are:
- Being unable to sit still, especially in calm or quiet surroundings
- Constantly fidgeting
- Being unable to concentrate on tasks
- Excessive physical movement
- Impulsivity means a person makes hasty actions that occur in the moment without first thinking about them and that may have high potential for harm; or a desire for immediate rewards or inability to delay gratification.
- Excessive talking
- Being unable to wait their turn
- Acting without thinking
- Interrupting conversations
- Little or no sense of danger
Diagnosis and test
There’s no specific test for ADHD, but making a diagnosis will likely include:
- Medical exam, to help rule out other possible causes of symptoms
- Information gathering, such as any current medical issues, personal and family medical history, and school records
- Interviews or questionnaires for family members, your child’s teachers or other people who know your child well, such as baby sitters and coaches
- ADHD criteria from the Diagnostic and Statistical Manual of Mental DisordersDSM-5, published by the American Psychiatric Association
- ADHD rating scales to help collect and evaluate information about your child
Treatment and medications
The first line of treatment for ADHD is stimulants.
- Stimulants: Stimulants are effective because the medication increases the brain chemical dopamine, which plays essential roles in thinking and attention.
- Non-Stimulants: These medications take longer to start working than stimulants, but can also improve focus, attention, and impulsivity in a person with ADHD. Two examples of non-stimulant medications include atomoxetine and guanfacine.
- Antidepressants: Although antidepressants are not approved by the U.S. Food and Drug Administration (FDA) specifically for the treatment of ADHD, antidepressants are sometimes used to treat adults with ADHD. Older antidepressants, called tricyclics, sometimes are used because they, like stimulants, affect the brain chemicals norepinephrine and dopamine.
Adding therapy to an ADHD treatment plan may help patients and families better cope with daily challenges.
- Behavioral therapy is a type of psychotherapy that aims to help a person change his or her behavior. It might involve practical assistance, such as help organizing tasks or completing schoolwork, or working through emotionally difficult events.
- Family and marital therapy can help family members and spouses find better ways to handle disruptive behaviors, to encourage behavior changes, and improve interactions with the patient.