Attention Deficit- Hyperactivity Disorder (ADHD)
Introduction
At some point, everyone has experienced having trouble concentrating on the task at hand. Especially as children, most of us probably would have rather been outside on a nice day instead of sitting in a classroom concentrating on schoolwork. Even so, most of us could focus if we needed to. Now, imagine being a child or an adult who is not able to focus on or complete any task, no matter how hard he or she tries. Or imagine being hyperactive all the time and not having the ability to control it...this is what life is like for a person with attention deficit-hyperactivity disorder (ADHD).
What is it?
Documented cases of ADHD can be found as early as the 1930s, but it wasn't until the 1990s that ADHD gained notice as a true psychiatric condition. ADHD, or ADD as it is sometimes called, is defined as "a disorder of inattention, hyperactivity, and impulsivity that presents early in life." This condition is thought to be predominately genetic in nature. Most of the patients that are diagnosed with ADHD will have a family history of ADHD or another psychiatric condition. Risk factors play an important role in how this condition develops. Currently there is no cure, but treatment is available to help patients function better in society and in their daily lives.
What causes it?
ADHD is related to brain function, but the true cause is still under investigation. One theory is that ADHD is caused by abnormalities in the anatomy of the brain; specifically in the prefrontal cortex, the part of the brain associated with response inhibition. Another theory involves abnormal levels of certain brain chemicals -- called neurotransmitters -- which are used to help brain cells communicate with each other. The brain chemicals that are thought to be affected in people with ADHD are dopamine, norepinephrine, and serotonin.
Symptoms of ADHD may result because the brain does not produce enough dopamine, which then leads to the impulsive symptoms and the lack of self-control commonly seen in patients with ADHD. It is speculated that if the brain does not produce enough norepinephrine, hyperactivity that is consistent with this condition can result. The final brain chemical that may play a part in ADHD is serotonin. If the child shows signs of aggression, then the brain may be producing too much serotonin.
At this point, the exact cause or causes of ADHD are not known, only theorized. As scientists advance their knowledge of the brain, the understanding of the causes of ADHD is expected to grow substantially.
Who has it?
ADHD is the most commonly diagnosed psychiatric illness in children. At present, it is estimated that, of the grade school age population (ages 6-12 years old), about 4%-12% suffer from ADHD. This translates into about two million children in the United States. To put this into perspective, in an average classroom of about 25 to 30 children at least one child will have ADHD.
ADHD affects both boys and girls, but it seems to affect boys about three times more often than it affects girls. Girls tend to prominently show the symptom of decreased attention whereas boys usually present with the symptom of hyperactivity, but this is not always the case.
About 18%-35% of children diagnosed with ADHD will also present with an additional psychiatric disorder such as depression, Tourrette's syndrome, or obsessive-compulsive disorder. The child of a parent with ADHD has a 50% chance of inheriting the disorder. In studies of identical twins with ADHD, if one identical twin has the disorder, there is a 92% chance that the other identical twin will also have ADHD.
Even though ADHD is a condition often diagnosed in childhood, the child usually does not grow out of it. ADHD will typically persist into adulthood, although symptoms of hyperactivity will usually not persist beyond middle childhood. Also, it is not uncommon for adult patients that are not diagnosed in childhood to be diagnosed with ADHD later in life. As patients with ADHD grow older and mature, the symptoms of ADHD may become less noticeable as the patients are able to learn strategies to cope with the disorder.
What are the risk factors?
Risk factors are characteristics that can predispose you to developing a condition. The following are common risk factors for ADHD:
- Mother's use of alcohol and other drugs during pregnancy
- Injury to or illness of the child before birth or around the time of birth such as infections, premature delivery, meningitis, or seizures that are caused by high fevers.
- Family residence near toxins in the environment (for example, lead)
- Family history of ADHD or other psychiatric condition
- History of child abuse or neglect
What are the symptoms?
Not everyone who is overly hyperactive, inattentive, or impulsive has ADHD. Everyone shows some of these behaviors at times, but the diagnosis requires that such behavior be demonstrated to a degree that is inappropriate for the person's age.
Diagnosis is based on symptoms and the length of time these symptoms are present. The list below describes the signs associated with the three main symptoms (inattention, hyperactivity, and impulsivity) of ADHD. To meet standard diagnostic criteria for ADHD, the child or adult must show at least six signs of inattention or six signs of either hyperactivity or impulsivity or both. These signs must be present for six months or more and must be severe enough to interfere with mental and physical development. The diagnostic behaviors must appear early in life, before age 7.
- Inattention, which includes making careless mistakes, paying poor attention to details, daydreaming, switching from one task to another without finishing the first task, giving effortless answers, interrupting/intruding, not listening when spoken to, difficulty in organization, and losing objects needed for tasks (toys, pencils, books, etc.).
- Hyperactivity, which includes acting driven or "on the go," excessive talking, getting out of a seat when remaining seated is expected, restlessness and fidgeting while seated, feeling the need to touch everything, running/climbing in inappropriate situations, or not being able to play or participate in activities quietly.
- Impulsivity, which includes acting without thinking, not being able to take turns, not being able to wait in line, not being able to wait for something they want, becoming violent (hitting another child) to get what they want, or making inappropriate comments.
Diagnosis of ADHD is not always straightforward because it sometimes presents with another psychiatric condition that may mask its symptoms, such as bipolar disorder, major depression, obsessive-compulsive disorder, and schizophrenia (most typically in adults).
Not all children with the disorder display each sign of ADHD all the time. Some children may have a pattern of being hyperactive and impulsive, but not inattentive. Other children may be inattentive, but not hyperactive. As a result, professionals have started recognizing three specific subtypes of ADHD.
- Predominately hyperactive-impulsive type, in which the child does not show significant inattention
- Predominately inattentive type, in which the child does not show significant hyperactivity or impulsivity.
- Combined type, in which the child displays both inattentive and hyperactive-impulsive symptoms.
How is it treated?
ADHD is a complex condition that can mimic other disorders; therefore, diagnosis plays a crucial role in the disorder. A physical exam by a doctor will help rule out physical illness such as a thyroid disorder, hunger, constipation, infection, or other disorders that could cause hyperactivity or inattentiveness. After the diagnosis of ADHD is made, options for treatment should begin with behavioral therapy and medication. Sometimes behavioral therapy is used alone but most often it is a combination of behavioral and medication therapies that are most effective.
The behavioral therapies include dividing large assignments into smaller more manageable tasks, giving the child rewards for completing certain tasks, speaking with a therapist, finding a support group, and manipulating situations to benefit the child's needs. Giving the child no time limits while taking a test, seating the child away from as many distractions as possible, and giving the child less homework may benefit a child with ADHD. To learn more about behavioral therapies, click on the "Helping Yourself" link above.
Medication is also a first-line option, but should typically not be used without behavioral therapy. At this time there are only a few medications that are approved for the treatment of ADHD. One class of drugs is called stimulants, and they work to improve concentration and allow the child or adult to focus on activities. This drug class includes dextroamphetamine (Dexedrine) and methylphenidate (Ritalin). Stimulants have been shown in studies to be effective in children with ADHD, with 70%-95% of children responding positively. If one stimulant medication does not work, another in the same class should be tried. The effects of long-term treatment with stimulants are not completely understood. It does not appear that stimulants stunt the growth of children as was previously thought. It is recommended that treatment with stimulants be reevaluated every year. Some unwanted effects from stimulants may be increased jitteriness, and decreased appetite; these effects tend to diminish over time with repeated use. Additional adverse effects may occur if more than the prescribed dose is taken, or use is not closely monitored by a healthcare professional.
Recently, drug companies have been making newer longer acting formulations of stimulant drugs. This includes a newly developed skin patch containing methylphenidate that can be worn on the hip. The patch, called Daytrana, is approved for use in children aged 6 to 12 and carries the same side effects as other methylphenidate medications. These new longer-acting medications are helpful because they allow ADHD medication to be dosed just once a day. This also avoids the problem of children having to take a dose of their medication while in school.
A more recent drug available for the treatment of ADHD is atomoxetine (Straterra). Atomoxetine is a non-stimulant medication that has been shown to be effective in children and adults with ADHD. It is currently considered a second line agent, and used after two unsuccessful treatment attempts with stimulants.
Antidepressants are another class of drugs that are used when treating ADHD. Antidepressants are considered second-line therapy to be used in patients that have ADHD with depression or when the stimulants are not working. Tricyclic antidepressants work in the body to prevent the nerves from taking up the chemicals such as dopamine and norepinephrine believed to be low in the brain in ADHD. The medication allows these chemicals to stay around longer in the blood and be used by the body in a more productive manner. Two tricyclic antidepressants are sometimes used to treat ADHD -- imipramine and desipramine. There are other medications that have been used for the treatment of ADHD but are not approved by the FDA. This type of treatment is called "off-label" use. These drugs include bupropion, clonidine, and guanfacine.
To learn more about first-line drug therapies for ADHD, click on the link below.
Helping Yourself
Treatment with medications should be supplemented with behavioral modification. The following are ways that parents and teachers can help a child with ADHD:
- Communicate regularly with the child's teachers, caregivers, and doctors about the progress of the child. This is especially important when the child begins medication or the child's dose of medication has been changed.
- Allow the child to have more time when taking a test.
- Give the child less homework so they can better focus.
- Take larger tasks and divide them into smaller tasks that are easier to manage. Give the child a reward for each smaller task completed.
- Praise behavior that you want to continue by giving rewards to the child.
- Giving the child a "time-out" for not completing a task.
- Emphasize the importance of appropriate behavior, such as waiting in line, sharing, or asking for help. If needed, a therapist may be able to show you how to do this.
- Remind your child that ADHD is not their fault.
- Remind your child not to be embarrassed by having to take medications at school. Other children take medications at school also (such as children with asthma).
- Join a support group. (Helpful websites to find support groups include: www.chadd.org, www.add.org, www.healthyplace.com )
- Join classes that give parents ideas and tools to help manage the child's behavior.
- Avoid over-stimulation. This may include allowing only one friend at a time to play with your child.
- Make a list of things to do for the day.
- Create a routine for yourself or your child. Stick to a routine so that it is easier for tasks to get accomplished.
What is on the horizon?
A recent brain imaging study performed by the National Institutue of Mental Health (NIMH), has found that brain development is delayed in patients with ADHD as compared to patients without ADHD. This study found that in children with ADHD, the brain develops normally. However, it is much slower to develop in certain areas, such as the frontal cortex, which is responsible for our ability to control thinking, planning, and attention. Additionally, the researchers also found a faster rate of development of the motor cortex in children with ADHD, which could account for the restless behavior found in children with ADHD. These findings may explain why many children seem to outgrow ADHD with time.
The focus of today's research is to better identify what causes ADHD and formulate a way to better diagnose this condition. These studies include brain imaging studies, genetic studies, and dietary studies. There are also ongoing studies looking at what effects long-term treatment will have on a child once they reach adulthood. In addition, there is continued research looking into non-stimulant medication for the treatment of ADHD.
References
- Popper C, West SA. Disorders Usually Diagnosed in Infancy, Childhood, or Adolescence. In Hales RE, Yudofsky SC, Talbot JA, eds: Textbook of Psychiatry. 3rd ed. Washington DC. American Psychiatric Press. 1999:827-855.
- American Academy of Pediatrics. Clinical Practice Guideline: Treatment of the School-Aged Child with Attention-Deficit/Hyperactivity Disorder. Pediatrics 2001, Oct; 108(4):1033-1044.
- Guevara JP, Stein MT. Evidence Based Management of Attention Deficit Hyperactivity Disorder. British Medical Journal, 24 Nov 2001; 323:1232-1235.
- Spencer TJ. Attention-Deficit/Hyperactivity Disorder. Archives of Neurology. 2002 Feb; 59(2):314-316.
- National Institute of Mental Health (NIMH). Attention Deficit Hyperactivity Disorder. Available at: http://www.nimh.nih.gov/publicat/helpchild.cfm Accessed March 2007.
- Diagnosis and Treatment of Attention Deficit Hyperactivity Disorder. NIH Consensus Statement Online 1998 Nov 16-18;16(2): 1-37. Available at: http://consensus.nih.gov/1998/1998AttentionDeficitHyperactivityDisorder110PDF.pdf Accessed January 2008.
- National Institute of Mental Health (NIMH). Attention Deficit Hyperactivity Disorder. Publication Number 96-3572. Revised 2003; Available at: http://www.nimh.nih.gov/publicat/adhd.cfm Accessed January 2008.
- National Institute of Neurological Disorders and Stroke. NINDS Attention Deficit-Hyperactivity Disorder Information Page. Available at: http://www.ninds.nih.gov/disorders/adhd/adhd.htm Accessed January 2008.
- Michelson D, Faries D, Wernicke J, et al. Atomoxetine in the Treatment of Children and Adolescents with Attention-Deficit/Hyperactivity Disorder: A Randomized, Placebo-Controlled, Dose Response Study. Pediatrics. 2001 Nov; 108(5):E83.
- Attention Deficit Disorder Association. AD/HD Frequently Asked Questions. Available at: http://www.add.org/help/faqs.html Accessed January 2008.
- Centers for Disease Control and Prevention. Attention Deficit Hyperactivity Disorder. Available at: http://www.cdc.gov/ncbddd/adhd/default.htm Accessed January 2008.
- Smoot LC, Boothby LA, Gillett RC. Clinical assessment and treatment of ADHD in children. International Journal of Clinical Practice. 2007 Oct; 61(10):1730-8.
Attention Deficit- Hyperactivity Disorder (ADHD) Health Condition Last Updated: January 2008
Note: The above information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist, or other healthcare professional. It is not intended to diagnose a health condition, but it can be used as a guide to help you decide if you should seek professional treatment or to help you learn more about your condition once it has been diagnosed.
- Predominately inattentive type, in which the child does not show significant hyperactivity or impulsivity.