ADHD is a developmental disorder. It is characterized primarily by “the co-existence of attentional problems and hyperactivity, with each behaviour occurring infrequently alone” and symptoms starting before seven years of age. It is one of the most common childhood disorders and can continue through adolescence and adulthood. ADHD is a problem with inattentiveness, over-activity, impulsivity, or a combination.
Signs and symptoms
Symptoms include difficulty staying focused and paying attention, difficulty controlling behaviour, hyperactivity (over-activity) and impulsivity. The symptoms are especially difficult to define because it is hard to draw the line at where normal levels of inattention, hyperactivity, and impulsivity end and clinically significant levels requiring intervention begin.
Based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) 4th edition, criteria listed below, three types of ADHD are classified:
1. ADHD Predominantly Inattentive Type: if criterion 1A is met but criterion 1B is not met for the past six months.
2. ADHD, Predominantly Hyperactive-Impulsive Type: if criterion 1B is met but criterion 1A is not met for the past six months.
3. ADHD, Combined Type: if both criteria 1A and 1B are met for the past 6 months
IA. Six or more of the following signs of inattention have been present for at least 6 months to a point that is disruptive and inappropriate for developmental level.
Predominantly inattentive type symptoms may include:
1. Be easily distracted, miss details, forget things, and frequently switch from one activity to another
2. Have difficulty maintaining focus on one task or play activities
3. Become bored with a task after only a few minutes, unless doing something enjoyable
4. Have difficulty focusing attention on organizing and completing a task or learning something new or trouble completing or turning in homework assignments, often losing things (e.g., pencils, toys, assignments) needed to complete tasks or activities
5. Not seem to listen when spoken to directly
6. Daydream, become easily confused, and move slowly
7. Have difficulty processing information as quickly and accurately as others
8. Often does not follow instructions and fails to finish schoolwork, chores, or duties in the workplace (not due to oppositional behavior or failure to understand instructions).
9. Fails to give close attention to details or makes careless mistakes in schoolwork
10.Often loses toys, assignments, pencils, books, or tools needed for tasks or activities
11.Is often forgetful in daily activities. 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.
12.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.
13.Often does not give close attention to details or makes careless mistakes in schoolwork, work, or other activities.
14.Often avoids, dislikes, or does not want to do things that take a lot of mental effort for a long period of time (such as schoolwork or homework).
IB. Six or more of the following signs of hyperactivity-impulsivity have been present for at least 6 months to an extent that is disruptive and inappropriate for developmental level:
Predominantly hyperactive-impulsive type symptoms may include:
1. Often fidgets with hands or feet or squirms in seat.
2. Often gets up from seat when remaining in seat is expected.
3. Often runs about or climbs when and where it is not appropriate (adolescents or adults may feel very restless).
4. Often has trouble playing or enjoying leisure activities quietly.
5. Is often “on the go” or often acts as if “driven by a motor”.
6. Often talks excessively.
7. Dash around, touching or playing with anything and everything in sight
8. Be constantly in motion, “on the go,” acts as if “driven by a motor,”
9. Have difficulty doing quiet tasks or activities.
10.Most symptoms (six or more) are in the hyperactivity-impulsivity categories.
11.Fewer than six symptoms of inattention are present, although inattention may still be present to some degree.
12.Six or more symptoms of inattention and six or more symptoms of hyperactivity-impulsivity are present.
1.Often has trouble waiting one`s turn.
2.Often interrupts or intrudes on others (example: butts into conversations or games).
4.Be very impatient
5.Blurt out inappropriate comments, show their emotions without restraint, and act without regard for consequences
Combined hyperactive-impulsive and inattentive
Six or more symptoms of inattention and six or more symptoms of hyperactivity-impulsivity are present.
Most children with ADHD have the combined type.
II. Some signs that cause impairment were present before age 7 years.
III. Some impairment from the signs is present in two or more settings (such as at school/work and at home).
IV. There must be clear evidence of significant impairment in social, school, or work functioning.
V. The signs do not happen only during the course of a Pervasive Developmental Disorder, Schizophrenia, or other Psychotic Disorder. The signs are not better accounted for by another mental disorder (such as Mood Disorder, Anxiety Disorder, Dissociative Identity Disorder, or a Personality Disorder).
Most people exhibit some of these behaviors, but not to the degree where such behaviors significantly interfere with a person’s work, relationships, or studies—and in the absence of significant interference or impairment, a diagnosis of ADHD is normally not appropriate. The core impairments are consistent even in different cultural contexts.Some children with ADHD primarily have the inattentive type. Others may have a combination of types. Those with the inattentive type are less disruptive and are more likely to not be diagnosed with ADHD.
Scientists are not sure what causes ADHD, although many studies suggest that genes play a large role. ADHD probably results from a combination of factors like genetics, environmental factors, and the social and physical environment.
Inherited from our parents, genes are the “blueprints” for who we are. Results from several international studies of twins show that ADHD often runs in families. Children with ADHD who carry a particular version of a certain gene have thinner brain tissue in the areas of the brain associated with attention. This research showed that the difference was not permanent, however, and as children with this gene grew up, the brain developed to a normal level of thickness. Their ADHD symptoms also improved.
PET scan: ADHD brains
Twin studies indicate that the disorder is highly heritable and that genetics are a factor in about 75 percent of all cases. Hyperactivity also seems to be primarily a genetic condition; however, other causes do have an effect. Researchers believe that a large majority of ADHD cases arise from a combination of various genes.The broad selection of targets indicates that ADHD does not follow the traditional model of “a simple genetic disease” and should therefore be viewed as a complex interaction among genetic and environmental factors. Even though all these genes might play a role, to date no single gene has been shown to make a major contribution to ADHD.
Twin studies have suggested that approximately 9 to 20 percent of the variance in hyperactive-impulsive-inattentive behavior or ADHD symptoms can be attributed to nonshared environmental (nongenetic) factors. Complications and infections during pregnancy and in early childhood, premature births are linked to an increased risk of developing ADHD.
The hunter vs. farmer theory is a hypothesis proposed by author Thom Hartmann about the origins of ADHD. The theory suggests that hyperactivity may be an adaptive behavior in pre-modern humans and that those with ADHD retain some of the older “hunter” characteristics associated with early pre-agricultural human society. According to this theory, individuals with ADHD may be more adept at searching and seeking and less adept at staying put and managing complex tasks over time.
Further evidence showing hyperactivity may be evolutionarily beneficial was put forth in 2006 in a study which found it may carry specific benefits for certain forms of ancient societies. In these societies, those with ADHD are hypothesized to have been more proficient in tasks involving risk or competition (i.e. hunting, mating rituals, etc.).
A genetic variant associated with ADHD (DRD4 48bp VNTR 7R allele), has been found to be at higher frequency in more nomadic populations and those with more of a history of migration. Consistent with this, another group of researchers observed that the health status of nomadic Ariaal men was higher if they had the ADHD associated genetic variant (7R alleles). However in recently sedentary (non-nomadic) Ariaal those with 7R alleles seemed to have slightly worse health.
Some researchers believe that relationships with caregivers have a profound effect on attentional and self-regulatory abilities. Behavior typical of ADHD has been found in children who have suffered violence and emotional abuse. Furthermore, Complex Post Traumatic Stress Disorder can result in attention problems that can look like ADHD.
The pathophysiology of ADHD is unclear and there are a number of competing theories. Research on children with ADHD has shown a proportionally greater reduction in the volume of the left-sided prefrontal cortex. A 2005 review of published studies involving neuroimaging, neuropsychological genetics, and neurochemistry found converging lines of evidence to suggest that four connected frontostriatal regions (the lateral prefrontal cortex, dorsal anterior cingulate cortex, caudate, and putamen) play a role in the pathophysiology of ADHD.
Diagnosis of ADHD
ADHD symptoms usually appear early in life, often between the ages of 3 and 6, and because symptoms vary from person to person, the disorder can be hard to diagnose. To be diagnosed with ADHD, symptoms must be observed in two different settings for six months or more and to a degree that is greater than other children of the same age. Children mature at different rates and have different personalities, temperaments, and energy levels. Most children get distracted, act impulsively, and struggle to concentrate at one time or another. Sometimes, these normal factors may be mistaken for ADHD.
ADHD should be diagnosed via a psychiatric assessment; to rule out other potential causes or comorbidities, physical examination, radiological imaging, and laboratory tests may be used.
Parents may first notice that their child loses interest in things sooner than other children, or seems constantly “out of control.” Often, teachers notice the symptoms first, when a child has trouble following rules, or frequently “spaces out” in the classroom or on the playground. No single test can diagnose a child as having ADHD. Instead, a licensed health professional needs to gather information about the child, and his or her behaviour and environment.
A specialist will also check school and medical records for clues, to see if the child`s home or school settings appear unusually stressful or disrupted, and gather information from the child`s parents and teachers. Coaches, babysitters, and other adults who know the child well also may be consulted.
Treating ADHD is a partnership between the physician/psychologist, parents or caregivers, and the child. It usually involves combination of medications, psychotherapy, behavior modifications and lifestyle changes. A 2005 study found that medical management and behavioral treatment is the most effective ADHD management strategy, followed by medication alone, and then behavioral treatment.
The most common type of medication used for treating ADHD is called a “stimulant.” Although it may seem unusual to treat ADHD with a medication considered a stimulant, it actually has a calming effect on children with ADHD. Many types of stimulant medications are available. One nonstimulant drug is also approved for the treatment of ADHD and is less likely to be misused.
Different types of psychotherapy are used for ADHD. Behavioral therapy aims to help a child change his or her behavior. It might involve practical assistance, such as help organizing tasks or completing schoolwork, or working through emotionally difficult events. It also teaches a child how to monitor his or her own behavior. Learning to give oneself praise or rewards for acting in a desired way, such as controlling anger or thinking before acting, is another goal of behavioral therapy. Parents and teachers also can give positive or negative feedback for certain behaviors. Clear rules, chore lists, and other structured routines can help a child control his or her behavior. Talk therapy for both the child and family can help everyone understand and gain control of the stressful feelings related to ADHD.
ADHD in adults
Symptoms may persist into adulthood for up to half of children diagnosed with ADHD. Many adults, however, remain untreated. Untreated adults with ADHD often have chaotic lifestyles, may appear to be disorganized and may rely on non-prescribed drugs and alcohol to get by. They often have such associated psychiatriccomorbidities as depression, anxiety disorder, bipolar disorder, substance abuse, or a learning disability.
ADHD in adults remains a clinical diagnosis. The signs and symptoms may differ from those during childhood and adolescence due to the adaptive processes and avoidance mechanisms learned during the process of socialization. Many adults who have the disorder don`t know it. These adults may have a history of failure at school, problems at work, or difficult or failed relationships. Many have had multiple traffic accidents. They may seem restless and may try to do several things at once, most of them unsuccessfully.
Treatment in adults
ADHD medications, including extended-release forms, often are prescribed for adults with ADHD, but not all of these medications are approved for adults. However, those not approved for adults still may be prescribed by a doctor on an “off-label” basis.
Psychotherapy, including cognitive behavioral therapy, also can help change one`s poor self-image by examining the experiences that produced it. The therapist encourages the adult with ADHD to adjust to the life changes that come with treatment, such as thinking before acting, or resisting the urge to take unnecessary risks.
– It is the most commonly studied and diagnosed psychiatric disorder in children, affecting about 3 to 5 percent of children globally and diagnosed in about 2 to 16 percent of school aged children.
– It is a chronic disorder with 30 to 50 percent of those individuals diagnosed in childhood continuing to have symptoms into adulthood. Those affected are likely to develop coping mechanisms as they mature, thus compensating for their previous ADHD.
– Medications have at least some effect in about 80% of the patients.
– ADHD exists alone in only about 1/3 of the children diagnosed with it. 2/3 appears in combination with other psychiatric diagnosis.
– ADHD is diagnosed two to four times more frequently in boys than in girls.
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