Attention Deficit Hyperactivity Disorder (ADHD) – Causes, Signs and Symptoms

ADHD

Also called: Attention Deficit Disorder, ADD, ADHD, Attention Deficit Hyperactive Disorder

Summary

Attention deficit hyperactivity disorder (ADHD) is a set of chronic conditions marked by an inability to pay attention, hyperactivity and a tendency to engage in impulsive acts. Children with ADHD often struggle academically and may have difficulty establishing friendships and other relationships. As a result, they may develop poor self-esteem.

There are three different forms of ADHD that affect children. They are:

  • Predominantly inattentive ADHD. Marked by difficulty paying attention.
  • Predominantly hyperactive/impulsive ADHD. Marked by difficulty controlling behavior.
  • Combined ADHD. Combines symptoms of the other two forms of ADHD. It is the most common form of ADHD.

Between 3 and 5 percent of school-aged children – or about 2 million children in the United States – have ADHD, according to the National Institute of Mental Health(NIMH). Boys are significantly more likely to be diagnosed with ADHD, but the disorder affects girls as well.

The exact cause of ADHD remains unknown, although scientists now believe that changes in brain structure are a leading cause of the disease. Heredity and exposure to certain environmental chemicals also appear to play a role in ADHD. Poor parenting or disruptions at home or school cannot cause ADHD, although they may exacerbate the condition.

Diagnosis of ADHD usually involves a variety of tests and interviews with parents, teachers and other adults who can describe aspects of the child’s behavior that may indicate ADHD.Medications called psychostimulant drugs are the most common treatment for ADHD and appear to be extremely effective. Psychotherapy is also helpful, particularly in children who are diagnosed with other disorders associated with ADHD. Specialized learning techniques can help children with ADHD to perform better in school. Parents can help their children to better deal with ADHD by providing additional structure to the child’s life and making expectations clear.

About attention deficit hyperactivity disorder

Attention deficit hyperactivity disorder (ADHD) is a set of chronic conditions marked by an inability to pay attention, hyperactivity and impulsive acts. It begins in childhood and can affect all areas of a patient’s life. Between 3 and 5 percent of school-aged children – or about 2 million children in the United States – have ADHD, according to the National Institute of Mental Health(NIMH). Boys outnumber girls by at least a three to one ratio, according to National Mental Health Association.

For many years, controversy has surrounded ADHD as some experts have differed over exactly what constitutes ADHD. In recent years, the NIMH has declared definitively that ADHD is a mental health condition.

Children with ADHD may develop low self-esteem resulting from difficulties in their relationships and struggles at school associated with the condition. Although ADHD always begins in childhood, it may persist into adulthood.

In some children, ADHD symptoms will diminish over time, but others will experience symptoms well into adulthood. Medications, psychotherapy and the support of family, teachers and other adults can help children to meet the challenges presented by ADHD.

Types and differences of ADHD

There are three major types of attention deficit hyperactivity disorder (ADHD). They include:

  • Predominantly inattentive ADHD. Marked by difficulty paying attention. Patients may struggle to concentrate and complete tasks and may be forgetful and easily distracted. They tend to have poor organizational skills and may appear to be lethargic and constantly daydreaming. This condition is most often diagnosed in adolescent girls, and is diagnosed if six or more symptoms of inattention have persisted for more than six months, according to the American Psychiatric Association (APA).
  • Predominantly hyperactive/impulsive ADHD. Marked by difficulty controlling behavior. Patients often fidget and are excessively restless. They may blurt out comments that are inappropriate and often do not think before they act. This condition is diagnosed if six or more symptoms of hyperactivity and impulsivity have persisted for more than six months.
  • Combined ADHD. Combines symptoms of the other two forms of ADHD. It is the most common form of ADHD. This condition is most often diagnosed in boys of elementary-school age. It is diagnosed when six or more symptoms associated with each of the two major forms of ADHD are present.

Some people use the term ADD to refer to attention-deficit disorder. However, this term is not used officially by the APA.

Potential causes of ADHD

Although the causes of attention deficit hyperactivity disorder (ADHD) are not fully understood, increasing numbers of experts believe that changes in brain structure are a leading cause of the disease. Brain scans have shown alterations of neural pathways that normally carry messages transmitted by the neurotransmitter dopamine. Normally, these messages reach the brain and affect attention, movement and motivation. However, impairment to these neural pathways may prevent the messages from reaching the brain, leading to inattention, lack of planning, increased impulsivity of behavior and lack of motor control. 

Other brain scans have found that patients with ADHD have lower levels of metabolic activity in the areas of the brain that dictate attention, social judgment and movement.

Additional factors that may contribute to the development of ADHD include:

  • Heredity. ADHD tends to run in families. Studies have shown that up to one-quarter of the close relatives of a child with ADHD are likely to have the disorder themselves, according to the National Institute of Mental Health(NIMH). Identical twins usually both have the disorder.
  • Maternal exposure to chemicals during pregnancy. Pregnant women who smoke, abuse alcohol and drugs, and are exposed to certain environmental poisons are more likely to give birth to children who are later diagnosed with ADHD. Environmental poisons associated with ADHD include polychlorinated biphenyls [PCBs], which have been banned in the United States, but remain in the environment. They are found in high levels in breast milk, which attracts the contaminants due to its high fat content.
  • Exposure to chemicals during childhood. Young children who are exposed to environmental toxins such as PCBs or lead (found mainly in paint and pipes of older buildings) are at increased risk for developmental and behavioral problems associated with ADHD symptoms.
  • Gender. Boys are three times as likely to develop the condition as girls, according to the NIMH.

Earlier theories suggested that minor head injuries or brain damage caused by infections or birthing complications might be responsible for ADHD. However, experts have not found evidence to support this hypothesis. Theories that too much or too little sugar may cause ADHD also appear to be unfounded. Poor parenting skills do not cause a child’s ADHD. Nonetheless, problems in the home or difficulties in school or community environments can exacerbate ADHD.

Signs and symptoms of ADHD

Attention deficit hyperactivity disorder (ADHD) typically manifests in an inability for a child to consistently pay attention coupled with hyperactive and impulsive behavior. The first symptoms are likely to appear between the ages of 4 and 6, although in many cases it is not apparent until the child begins school. Symptoms of hyperactivity and impulsiveness typically precede inattention by up to a year or more.

Inattention may become evident in careless mistakes during schoolwork or an inability to properly listen to the conversation or direction of others. Children with ADHD frequently struggle to finish tasks and are often forgetful. Rather than appearing hyperactive, children who struggle predominantly with inattention may appear sluggish, passive and unmotivated.

Hyperactive children may fidget excessively or squirm in their seats. They may run or climb a lot and have difficulty playing quietly. Excessive talking and interrupting of others also are typical signs of hyperactivity.

A child with ADHD is unlikely to display all of the symptoms associated with the disorder. Gender may also play a role in which symptoms are exhibited. For example, boys are more likely to be hyperactive whereas girls are more likely to be inattentive. In regard to inattentiveness, girls are more likely to daydream whereas boys are more likely to play aimlessly.

Children with ADHD are often more sensitive to various sights, sounds and textures than those without the disorder. When a child with ADHD becomes overstimulated, they may lose control in a way that manifests as aggressive behavior or giddiness. Children with ADHD may have difficulty making friends and developing other meaningful relationships. This is at least partially because they have difficulty following rules and waiting their turn, and may talk excessively. These qualities may be off-putting to peers.

Children with ADHD are at much higher risk of academic difficulty than other children. Between 40 and 60 percent of children with ADHD have major learning difficulities, according to the National Mental Health Association. Hyperactivity, poor organizational skills and difficulty paying attention may all contribute to this lack of school success. Minor trauma, such as fractures and lacerations, is also more common in children with ADHD. Teenagers with ADHD are significantly more likely to be involved in automobile accidents than those without ADHD. Troublesome behaviors such as delinquency or drug and alcohol abuse may also be associated with some people with untreated ADHD.

Diagnosis methods for ADHD

Parents are usually urged to contact a physician if their child is having trouble concentrating, remaining still or behaving properly. Despite the fact that symptoms of ADHD appear before age 7, many experts agree that ADHD should not be diagnosed in a child prior to age 7. This is because many of the symptoms associated with ADHD are often present in a milder form in younger children who do not have the condition. For example, children and adolescents are often noted for having higher energy levels and shorter attention spans than adults. 

Diagnosing ADHD is not easy. There is no single test that reveals the presence of the disorder. A physician will perform a complete physical examination and compile a thorough medical history. The physician may use questionnaires or interviews with parents, teachers, babysitters, coaches and others who may describe behaviors typically associated with ADHD. Teachers in particular may be asked to record their observations on standard evaluation forms called behavior rating scales. These forms take advantage of a teacher’s experience working with various children by asking the teacher to compare the child’s behavior to others of the same age group. The physician will look for behaviors that have a long history, and will note when they occur.

Questions that may be asked by the physician include:

  • At what age did the child first begin displaying symptoms of potential ADHD?
  • Do problems tend to appear periodically or are they chronic?
  • Does the child struggle academically?
  • Does the child have trouble maintaining relationships?
  • Are there other problems or symptoms that may be apparent?

Standardized testing also may be used to evaluate a child’s mental health status, intelligence level, learning abilities and social adjustment.

Before diagnosing ADHD, the physician will rule out other potential causes of symptoms. Sleep disorders such as sleep apnea (temporary cessation of breathing during sleep) are frequently the cause of inattention in children. Other disorders that cause symptoms similar to ADHD include hyperthyroidism (excessive production of thyroid hormone), seizure disorders, and vision or hearing problems. Sudden life changes (such as the death of a loved one) can also cause emotional disruption in children that may appear similar to ADHD.

A diagnosis of ADHD is often made in concert with other health professionals such as psychiatrists, developmental and behavioral pediatricians, and behavioral neurologists. Parents are urged to seek out the care of health professionals who have experience in diagnosing children with ADHD.

A diagnosis of ADHD is made according to certain criteria established by the American Psychiatric Association. Patients should exhibit six or more symptoms in at least one of two categories that persist for at least six months and that are maladaptive and inconsistent with developmental level.

Regarding inattention, the symptoms include:

  • Fails to pay close attention to details or makes careless errors in schoolwork, work or other activities.
  • Has difficulty staying focused on tasks or play activities.
  • Does not appear to listen when spoken to directly.
  • Fails to carry out instructions or to finish schoolwork, chores or workplace duties. This cannot be the result of oppositional behavior or a failure to understand directions.
  • Has difficulty with organization of tasks or activities.
  • Avoids or dislikes tasks that involve concentrated mental effort.
  • Loses items necessary to complete tasks or activities, such as books and pencils or toys.
  • Becomes easily distracted by extraneous stimuli.
  • Is forgetful in daily activities.

Regarding hyperactivity and impulsivity, the symptoms include:

  • Fidgets with hands or feet or squirms in seat.
  • Leaves seat in classroom when expectation is to remain seated.
  • Runs about or climbs excessively in inappropriate situations.
  • Has difficulty playing or engaging in leisure activities quietly.
  • Is often “on the go” or acts as if “driven by a motor.”
  • Talks excessively.
  • Blurts out answers before question is finished.
  • Has dfficulty awaiting turn.
  • Interrupts or intrudes on others.

These symptoms should be present before the age of 7, and the impairment should be present in two or more settings.

In addition, the patient must have clinically significant impairment in social, academic or occupational functioning, and symptoms cannot be due to an autistic spectrum disorder, schizophrenia, or another psychotic disorder and cannot be better accounted for by another mental disorder. 

Patients are diagnosed with predominantly inattentive ADHD if they have symptoms that fit this category but not the hyperactive-impulsive type over a period of six months. They are diagnosed with hyperactive-impulsive ADHD if the opposite is true. Finally, the patient will be diagnosed with combined ADHD if the criteria from both of the two major categories are met over a period of six months.

Conditions related to ADHD

Children who are diagnosed with ADHD are often diagnosed with another form of mental illness. Some disorders that may be diagnosed in association with ADHD include:

  • Anxiety disorders. Conditions marked by debilitating or disruptive fears or anxieties. They occur in 25 percent of children diagnosed with ADHD, according to the National Alliance on Mental Illness (NAMI) and the National Institute of Mental Health (NIMH).
  • Conduct disorder. Condition marked by significant antisocial behavior such as theft and physical violence. It occurs in 20 to 40 percent of children with ADHD, according to NIMH.
  • Depression. Persistent feelings of sadness that interfere with a person’s ability to enjoy life. It occurs in about one-third of children with ADHD, according to NIMH.
  • Learning disabilities. Conditions marked by low academic performance despite normal range of intelligence. About 25 percent of children diagnosed with ADHD also have a learning disability, according to NAMI and the NIMH.
  • Bipolar disorder. A condition in which the patient’s mood cycles between intense highs (mania) and lows (depression). It occurs in one-fifth of children with ADHD, according to NIMH.
  • Oppositional defiant disorder (ODD). A pattern of negative or hostile behavior toward authority figures. It appears in about half of all children with ADHD, according to NIMH.
  • Tourette’s syndrome(TS). Neurological disorder marked by compulsive muscular or vocal tics. Although only a small percentage of patients with ADHD have Tourette’s, at least half of those diagnosed with Tourette’s also have ADHD, according to NAMI.

Treatment options for ADHD

Considerable debate remains over the best way to treat attention deficit hyperactivity disorder (ADHD). Medications called psychostimulant drugs are the most common treatment for the disorder, and are believed to boost levels of the neurotransmitter dopamine (associated with activity) and norepinephrine. This improves attention and reduces impulsiveness, hyperactivity and aggressive behavior. 

Antidepressants may also be used to treat ADHD, especially in children who are depressed or who do not respond to psychostimulant therapy. However, the U.S. Food and Drug Administration (FDA) recently required that all antidepressants include a label warning that they may increase the risk of suicidal thoughts and behaviors in children.

Children who are treated with medications may consult the physician weekly until it is clear a helpful dosage level has been established. At that point, visits are likely to be scheduled every few months. Parents are urged to consult a physician about any side effects associated with medication use, including loss of appetite, problems sleeping, increased irritability, excessive weight loss and suicidal thoughts. Changes in dosage levels can usually reduce or eliminate these side effects.

Up to 90 percent of children with ADHD respond to medication, according to the National Mental Health Association (NMHA). However, the drugs do not cure ADHD, and many patients find that a combination of medications, special attention in the classroom, and family and community support remain the best treatment approach. About 80 percent of children who take medications for their ADHD continue to need the drugs during their teen years, according to the National Institute of Mental Health (NIMH).

Various forms of therapy including standard psychotherapy, behavior therapy, family therapy and social skills training, may also help relieve ADHD symptoms.Parents may benefit from taking parenting skills training that teach special techniques for addressing the unique challenges of raising a child with ADHD. For example, parents may learn to use a token or point system to reward their child for good behavior. Therapy is particularly helpful for children who are diagnosed with both ADHD and an associated condition such as depression or anxiety.

Parents can help their children to better deal with ADHD by providing structure to the child’s life and making expectations clear. Keeping children on a schedule of activities (including eating, sleeping, homework and play times) and encouraging children’s efforts and good behavior can also help. Parents are urged to communicate with their children to make sure directions are clearly understood. All of these techniques can be improved during parenting skills training.

Questions for your doctor regarding ADHD

Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions related to attention deficit hyperactivity disorder (ADHD):

  1. How do I know if my child’s behavior is normal or might be a sign of ADHD?
  2. What behaviors should I watch for that might indicate that my child has a problem?
  3. Do I need to contact my child’s teachers, babysitters or others who might be able to help you make the proper diagnosis?
  4. Which type of ADHD do you suspect in my child? Why?
  5. Is it possible that my parenting style is responsible for my child’s ADHD?
  6. How can medications help my child’s symptoms?
  7. What are the potential side effects of these medications?
  8. Based on your examination, is possible that my child has another emotional disorder related to ADHD?
  9. What steps can I take to help my child meet the day-to-day challenges of ADHD?
  10. Will my child outgrow his/her ADHD or is it likely to last a lifetime?
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