Download Definition

Definition
• According to the fourth edition of the American Psychiatric
Association's (APA) DSM (DSM-IV), ADHD is a behavioral and
neurocognitive condition characterized by developmentally
inappropriate and impairing levels of gross motor overactivity,
inattention, and impulsivity. There are five main diagnostic criteria:
(1) an onset before age 7 years; (2) duration greater than 6 months;
(3) an 18-item symptom list of which 6 of 9 inattention or 6 of 9
hyperactive/impulsive symptoms have persisted for at least 6
months to a degree that is maladaptive and inconsistent with
developmental level; (4) some impairment in two or more settings;
and (5) symptoms that do not occur exclusively during the course of
a pervasive developmental disorder, schizophrenia, or other
psychotic disorder and are not better accounted for by another
mental disorder, such as depression.
• ADHD is diagnosed by history taken from the
parent and at least one other adult, such as a
teacher or coach. As with many psychiatric
disorders, there is no simple objective test,
such as a blood test, that can aid in making
the diagnosis.
Etiology
• Although the etiology of ADHD yet has to be determined, there is a
growing consensus that the condition involves functional and
anatomical dysfunction in the brain's frontal cortex and basal
ganglia segments of the cortico-basal ganglia-thalamo-cortical
circuitry. These areas support the regulation of attentional
resources, the programming of complex motor behaviors, and the
learning of responses to reinforcement. Theories involving these
areas have been examined in series involving neurobiological
studies of healthy humans, humans with ADHD, and animal models.
Reviews by Castellanos and Swanson have delineated ADHD's
complexity, its theoretical diversity, and the many questions yet to
be resolved. The symptoms of ADHD are multidimensional,
suggesting the interaction of neuroanatomical and neurochemical
systems. The current evidence for the neurobiological factors
suggests that genetics and neurochemistry play key roles.
• First-degree relatives of children with ADHD
have a 20 to 25 percent risk for ADHD,
compared with 4 to 5 percent for relatives of
controls. If a parent has ADHD, 50 percent of
his or her offspring are likely to have that
condition
Thyroid Receptor B Gene
• Thyroid Receptor B Gene
• Early molecular genetic studies showed that
mutation of the thyroid receptor B gene, which
causes resistance to thyroid hormone, was
associated with high rates (61 percent) of
hyperactivity and impulsivity (but not inattention)
in affected children and adults. However, only 1
of 2,500 patients with ADHD had this thyroid
abnormality, which generally was very rare. Thus,
this gene could not be a major cause of ADHD.
• Dopamine Type D2 Receptor Gene
• Dopamine Transporter Gene
• Dopamine 4 Receptor Gene
Neuroanatomical Aspects
• Mirsky and Castellanos described neuroanatomical
correlations for the
• superior and temporal cortices with the focusing of
attention;
• external parietal and corpus striatal regions with motor
executive function;
• the hippocampus with the encoding of memory traces;
• the prefrontal cortex with the act of shifting from one
salient stimulus to another;
• and brainstem areas such as reticular thalamic nuclei
with the sustaining of attention
• Hechtman's review of magnetic resonance
imaging (MRI), positron emission tomography
(PET), single emission computed tomography
(SPECT), and functional MRI studies suggested
decreased volume and activity in prefrontal
areas, anterior cingulate, globus pallidus,
caudate, thalamus, hippocampus, and
cerebellum in children with ADHD. These
findings are supported by morphological
studies of Castellanos and colleagues
• Neurotransmitters in ADHD
• Certain brain areas have been associated with specific
neurotransmitters—for example, the caudate nucleus and
corpus striatum with dopamine and
• the median raphe with serotonin. Even so,
neuroanatomical studies of neurotransmitters have proven
to be very complex because these neuroanatomical regions
of interest receive projections from multiple nuclei and
neurotransmitter pathways, confounding theories that
posit dysfunction in a single neurotransmitter system as the
etiology of ADHD. However, for clarity, each
neurotransmitter system is discussed separately in what
follows.
• Dopamine System
• Noradrenergic System
• Serotonergic System
• Environmental Factors
• High lead exposure
• and maternal smoking
• have been associated with higher rates of diagnosis of ADHD.
However, it has been difficult for investigators working with children
affected by adversity to determine whether their ADHD symptoms
reflect a response to
• negative parenting, a harsh environment, a genetically influenced
biological problem, or some interaction among these factors. Only
with further multifaceted prospective research, such as the Centers
for Disease Control and Prevention/National Institutes of Health
National Children's Study in the United States, will there be a
clearer, more comprehensive understanding of the possible
etiology, natural history, and treatment of ADHD.
• Diagnostic Criteria for Attention-Deficit/Hyperactivity
Disorder According to the Text Revision of the Fourth
Edition of the Diagnostic and Statistical Manual of
Mental Disorders
• Either (1) or (2):
– six (or more) of the following symptoms of inattention
have persisted for at least 6 months to a degree that is
maladaptive and inconsistent with developmental level:
Inattention
• often fails to give close attention to details or makes careless
mistakes in schoolwork, work, or other activities
• often has difficulty sustaining attention in tasks or play activities
• often does not seem to listen when spoken to directly
• often does not follow through on instructions and fails to finish
schoolwork, chores, or duties in the workplace (not due to
oppositional behavior or failure to understand instructions)
• often has difficulty organizing tasks and activities
• often avoids, dislikes, or is reluctant to engage in tasks that require
sustained mental effort (such as schoolwork or homework)
• often loses things necessary for tasks or activities (e.g., toys,
school assignments, pencils, books, or tools)
• is often easily distracted by extraneous stimuli
• is often forgetful in daily activities
• six (or more) of the following symptoms of
hyperactivity impulsivity have persisted for at
least 6 months to a degree that is maladaptive
and inconsistent with developmental level:
Hyperactivity
• often fidgets with hands or feet or squirms in seat
• often leaves seat in classroom or in other situations in
which remaining seated is expected
• often runs about or climbs excessively in situations in
which it is inappropriate (in adolescents or adults, may
be limited to subjective feelings of restlessness)
• often has difficulty playing or engaging in leisure
activities quietly
• is often “on the go” or often acts as if “driven by a
motor”
• often talks excessively
• Impulsivity
• often blurts out answers before questions have been
completed
• often has difficulty awaiting turn
• often interrupts or intrudes on others (e.g., butts into
conversations or games)
• Some hyperactive impulsive or inattentive symptoms that
caused impairment were present before age 7 years.
• Some impairment from the symptoms is present in two or
more settings (e.g., at school [or work] and at home).
• There must be clear evidence of clinically significant
impairment in social, academic, or occupational
functioning.
• The symptoms do not occur exclusively during the course of
a pervasive developmental disorder, schizophrenia, or
other psychotic disorder and are not better accounted for
by another mental disorder (e.g., mood disorder, anxiety
disorder, dissociative disorder, or a personality disorder).
• Associated Factors
• Children with ADHD might have areas of
impairment that are not listed under the DSMIV symptom criteria covered exactly by the 18
symptom exemplars of hyperactivity,
impulsivity, or inattention
•
•
•
•
Behavioral
Children with ADHD often
lack persistence.
They become bored with interactive games with
peers, and leave such games early before they are
finished. They find it
• difficult to delay gratification.
• They show variable performance on tasks, which
may negatively affect self-esteem
• Cognitive
• Children and adolescents with ADHD often show
difficulty with time management and do not develop
an internal sense of pace in planning tasks.
• This poor sense of time leads to problems in
estimating the actual
• difficulty of waiting in line,
• planning how much time a task requires,
• or even knowing when to come home when out
playing with other children
Deficit of Behavioral Inhibition and
Executive Functioning
• Lack of behavioral inhibition has been postulated to lead to
impairments in
• motivation, arousal, ability to delay gratification, working memory,
and self-regulation of affect.
• Dysfunction in these areas is said to impair executive functioning,
interfering with goal-directed behavior.
• However, executive functioning problems occur in other psychiatric
disorders of childhood, such as depression, and are not specific to
ADHD. Neuropsychological tests often used by clinicians tap into
but do not totally explain a child's or adolescent's executive
functioning.
• Recent data show that academic functioning is more strongly
affected by an impulsive need to get through tests quickly, a deficit
closely linked to poor behavioral inhibition rather than poor
executive functioning.
• Poor inhibitory control has been postulated to lead to
impairments in
• motivation, arousal, delay of gratification, working
memory, and self-regulation of affect.
• This has been assessed in the laboratory using Stop
Signal Tasks and the Go-No Go test. Other deficits
include greater intraindividual variability of reaction
time, cerebellar associated deficits in motor timing,
inability to delay response to reward, and possible
alternations in synchronization in the cingulateprecuneus default mode network
• Dysfunction in these areas is said to impair executive functioning,
interfering with
• goal-directed behavior
• . However, executive functioning problems occur in other
psychiatric disorders of childhood, such as depression, and are not
specific to ADHD. On any given measure of executive function, less
than half of children with ADHD have been found to be impaired.
Although findings of executive function deficits can appear in the
results of testing children with ADHD, the lack of such deficits does
not rule out the disorder. Some neuropsychologists use the
Behavior Rating Inventory of Executive Function (BRIEF) as part of
their evaluation battery, but this measure has not been used in a
prospective manner to assess the effect of stimulant medications
• Emotional
• ADHD is often associated with dysregulation of
affect, resulting in temper outbursts, mood
lability, and reactivity. Moods can change
dramatically with no obvious connection with
what's going on in the environment.
• The reaction of others and the consequences of
an action are often poorly understood by the
individual with ADHD, who has moved on to
something else and does not understand what
the fuss is about.
• Social
• Individuals with ADHD may have problems accurately interpreting
nonverbal social cues and thus react inappropriately.
• This is associated with reports from peers, who report these
individuals to be intrusive, bossy, and insensitive to the needs of
others. There is trouble cooperating with other children and
following rules in games. Children with ADHD often have strong
reactions, overreacting to situations that can be predictably
triggered by others, leading to teasing and ridicule. Their tendency
to respond to frustration in social situations can lead to verbal or
physical aggression, a strong stimulus for peer rejection, which has
been shown to be a reliable long-term negative predictor of
development, particularly in adolescence
• Course and Prognosis
• Parents often notice very high levels of gross motor
activity when the child with ADHD is a toddler, just
when the child has learned to walk independent of the
parent's help. However, the energy, oppositionality,
and curiosity of toddlers can be confused with the
excessive, almost random motion of older children
with ADHD, so that one must be cautious when
applying the ADHD diagnosis to a preschooler. Usually,
the ADHD diagnosis is first applied in primary school,
during grades 1 to 6, when adjustment to the
sedentary learning style is compromised.
• The motor and attentional symptoms and impairment create a consistent
picture through early adolescence, when often the external overactivity
lessens but the internal restlessness does not.
• Whereas the school-age child is mostly at risk for
• academic failure and peer rejection, the adolescent with ADHD who is
untreated has other risks in excess of peers with no mental disorder,
including a threefold increase in substance use and abuse, trouble with
the law, and an increased rate of automobile accidents when the teenager
begins to drive.
• Approximately 60 percent of those who develop childhood ADHD continue
to be impaired well into adult life, with prevalence estimates suggesting
that 4 percent of adults may suffer from ADHD. These individuals may
show instability in job status and relationships, even if the numbers of
ADHD symptoms do not meet the threshold required for the childhood
diagnosis.
‫شیوع ‪• %7-3‬‬
‫سن شروع‪4‬و‪5‬و‪• 6‬‬
‫جنس پسرها‪6‬به ‪1‬از نظر هوشی •‬
‫غذا •‬
‫عواقب اختالل سلوک –اختالل یادگیری‪-‬وسواس‪-‬تیک‪• -‬‬
‫افسردگی‪-‬اختالل دوقطبی‪-‬مصرف مواد‪-‬اختالل هماهنگی‬
‫حرکتی‪-‬اختالل اضطراب •‬
‫زمان دارو •‬
‫عوارض دارو •‬
‫تا کی به مصرف ادامه می دهیم •‬
‫توقع خود را کم کنید •‬
‫هرزمان به یک مشکل رفتاری توجه کنید •‬
‫دستورات ساده •‬
‫تشویق بهتر از تنبیه •‬
‫مدیریت زمان •‬
‫ورزش •‬
‫ارتباط با معلمان •‬
‫محیط ارام •‬
• Treatment
• Stimulants
• Amphetamines and methylphenidates are two groups of stimulant
medication that have received U.S. Food and Drug Administration (FDA)
approval for the treatment of youth with ADHD. They are marketed in
both immediate release (IR) and long-acting preparations and can be
purchased as either generic or branded versions. Since 2000, multiple
stimulants have been marketed with FDA approval for ADHD treatment,
including long-duration mixed salts of amphetamine, dexmethylphenidate,
osmotic-release methylphenidate, the prodrug lisdexamfetamine, and
beaded methylphenidate. All of these products include either
amphetamine or methylphenidate as the active ingredient. These
chemicals structurally resemble the catecholamine neurotransmitters
dopamine (DA) and norepinephrine (NE). All can be described as
psychostimulants, which refers to their ability to increase central nervous
system activity in brain regions (Table 42.1-2).
• Nonstimulant Medication in the Treatment of
Children with ADHD
• Atomoxetine HCl
• Tricyclic Antidepressants
• α-Adrenergic Agents
• Bupropion
• Psychosocial Treatment of Children with ADHD
• Multimodal Treatment (MTA Study)