Attention-Deficit Hyperactivity Disorder (ADHD)

Specialty: Neurology/Pediatrics/Development Disorders

Author: Nicole Nwosu

Editor:Abidemi Oseni


Attention-deficit hyperactivity disorder (ADHD) is a neuro-developmental disorder typically
associated with children. It is described as an impairment in functioning caused by inattention,
impulsiveness and hyperactivity (Holland and Sayal, 2018). In the adult population, it impacts
social interactions, work productivity and academic achievement, displaying how the disorder
has a significant influence on various areas of a patient’s life (Xue et al., 2019). ADHD is also
known to be associated with other conditions such as oppositional defiant disorder, mood
disorders, anxiety disorders, substance abuse, conduct disorder and tic disorders (Austerman,

Social Media Summary

Attention-deficit hyperactivity disorder (ADHD) is a neuro-developmental disorder typically
associated with children.Many of these children may have difficulties sitting still, waiting their
turn,being fidgety, and acting impulsively. Treatment of ADHD usually encompasses a
combination of therapy and medication intervention which in some cases includes behavioral
strategies in the form of parent management training and school intervention. Treatment for
many children often alternate between various medication options depending on the efficacy
and tolerability of the medication. The ultimate treatment goal is to improve symptoms to restore
functioning at home and at school.
Social media handle Instagram: @abidemi_oseni

Epidemiology of ADHD

Studies suggest that ADHD impacts about 5% of school-age children (Holland and Sayley,
2018). In the United States, more than 1 in 10 school-age children meet the criteria for the
diagnosis of ADHD followed by 1 in 5 for high school boys and 1 in 11 for high school-aged girls
(Manos et al., 2017). The estimated prevalence of ADHD in the adult population is 2.5% (Xue et
al., 2019). Despite research in the past stating that most children with ADHD recover in
adulthood, recent research has concluded that symptoms of ADHD continue into adulthood for
two-thirds of cases (Zue et al., 2019). In addition, prescription and diagnosis rates vary between
countries. For instance, prescribing rates in Denmark are 0.9% whereas, in Canada and
Iceland, the percentage is between 4.6-4.7% (Holland and Sayal, 2018).

Etiology of ADHD

Etiology of ADHD

Despite ADHD being considered highly heritable, the genes that contribute to the phenotypic
expression of ADHD have been hard to discover (Sciberras et al., 2017). Research has found a
number of possible genes having an impact in predicting ADHD in patients such as SNAP25
and SLC6A4. While genome-wide association studies have started to be conducted, nothing
significant has been published. While not all the risk for ADHD is genetic, there is also
environmental risk due to heritability, a factor of gene and environment interaction (Sciberras etal., 2017).

In fact, about 10 to 40% of the variability of ADHD is recorded to be because of
environmental factors. Because ADHD appears early in life, most research has been conducted
on the role the prenatal environment may have on the development of the disorder (Sciberras et
al., 2017).

Developmental Risk Factors for ADHD include (Austerman, 2015):

● Prematurity

● Prenatal complications

● An anoxic (oxygen deprivation) event

● Nutritional deficits (such as iron and zinc)

● Lack of proper socialization

● Heritability


Symptoms of ADHD

Holland and Sayal (2018) describe that those with ADHD have three core symptoms:
hyperactivity, impulsiveness and inattention, causing impairment in functioning (Holland and
Sayal, 2018). According to the DSM-5, symptoms vary but typically include numerous factors for
diagnosis that can be found in the next section (American Psychiatric Association, 2013.
Symptoms of inattention linked to ADHD include that the patient (American Psychiatric
Association, 2013:

● Is easily distracted

● Loses things essential for tasks and activities

● Forgetful in daily activities

● Avoids, dislikes or is reluctant to participate in tasks that require mental effort over a
prolonged period of time.

● Has problems organizing tasks and activities

● Does not follow through on instructions and fails to complete schoolwork, chores, or
duties in the workplace

● Does not appear to listen when directly spoken to

● Has issues holding attention on play activities or tasks

● Makes careless mistakes and fails to pay close attention to details of activities
Symptoms of hyperactivity and impulsivity linked to ADHD include that the patient (American
Psychiatric Association, 2013):

● Often runs around or climbs in circumstances where it is not appropriate (in older people
this is tied to feeling restless)

● Talks excessively

● Blurts out an answer before a question has been completed

● Fidgets with or taps hands or feet, or squirms in seat

● Leaves seat in situations when remaining seated is expected

● Is unable to play or take part in leisure activities quietly

● Interrupts or intrudes on others often

● Issues waiting their turn

● Is often “on the go”

Developmental Risk Factors for ADHD include (Austerman, 2015)

Diagnosis of ADHD

Pathological Diagnosis

ADHD is associated with cognitive and functional deficits linked to abnormalities in the brain
(Magnus et al., 2022). For instance, patients that have ADHD typically have smaller anterior
cingulate gyrus and dorsolateral prefrontal cortexes (parts of the brain). These changes are
thought to account for goal-directed behavior issues (Magnus et al., 2022). In addition, using
fMRI, activity in the frontostriatal region is reduced as well. However, ADHD is known to be a
clinical diagnosis. There are no standard laboratory or imaging results among patients with
ADHD (Magnus et al., 2022).

Clinical Diagnosis

Diagnosis of ADHD in children includes proof of inattention, hyperactivity or impulsivity or both
with a severity that impacts functioning for development in two or more settings being present
before the age of 12 and it cannot be linked to another health disorder like trauma, anxiety or
depression (Manos et al., 2017). Behaviors of ADHD had to have been present for six months
before being diagnosed. Diagnostic requirements vary within themselves (American Psychiatric
Association, 2013).

The following conditions must be met for a diagnosis of ADHD (American Psychiatric
Association, 2013):

● That multiple inattentive or hyperactive-impulsive symptoms were present in individuals
before the age of 12.

● That multiple symptoms are present in two or more settings.

● That there is proof of evidence that the symptoms of the patient interfere with, or reduce
the quality of work, school or social functioning.

● That the symptoms presented are not explained by another mental disorder, for
instance, anxiety, dissociative, mood, or personality disorder. That the symptoms do not
happen only during the episode of schizophrenia or another psychotic disorder.

● To be diagnosed with ADHD linked to inattention, six or more symptoms of inattention
must be present in kids up to the age of 16, or five or more for 17+ children and adults.

● To be diagnosed with ADHD linked to hyperactivity-impulsivity, six or more symptoms of
hyperactivity-impulsivity must be present in kids aged 16 and below or five or more for
children 17+ and adults. For both, symptoms must have been present for at least 6

The following conditions must be met for a diagnosis of ADHD (American Psychiatric Association, 2013):

There are three types of presentations of ADHD based on symptoms (American Psychiatric
Association, 2013):

● Combined Presentation: if a specific amount of symptoms within both criteria of
inattention and hyperactivity-impulsivity have been present for six months.

● Predominantly Inattentive Presentation: If enough symptoms of inattention but not
hyperactivity-impulsivity were present for six months prior to diagnosis.

● Predominantly Hyperactive-Impulsive Presentation: if enough symptoms of hyperactivity-
impulsivity but not inattention were present for six months prior to diagnosis.

For older adults, symptoms of ADHD might appear differently compared to children. For
instance, hyperactivity in kids may be displayed as extreme restlessness or a tendency to wear
other people out with their activity for adults (American Psychiatric Association, 2013).

Treatment of ADHD

Pharmacological Treatment

Pharmacological therapy is the main view of treatment for those who have ADHD. It is divided
into stimulants and non-stimulants (Magnus et al., 2022).
Stimulants are either amphetamines or methylphenidates (Magnus et al., 2022). Both of these
stimulates are involved in blocking the neurotransmitter, dopamine in reuptake. Stimulants are
considered to be the main form of treatment for ADHD. They are effective in 70% of patients.
And there are multiple categories for the subtypes of stimulants such as immediate-release,
sustained release, long-acting or extended-release. The side effects of stimulants involve
changes in blood pressure, sleep, risk of dependency, and decreased appetite (Magnus et al.,

Drug therapies have their limitations, for instance, high dropout rates and adverse effects (Xue
et al., 2019). Some patients may show partial or no responses to the treatment they are given
as well. A number of studies over the past twenty years have researched non-pharmacologic
interventions for those with ADHD, using cognitive and behavioral methods concerning
symptoms (Xue et al., 2019).

Concerning non-stimulant options, there are two types for ADHD: antidepressants and alpha
agnosis (Magnus et al., 2022). In the former category, atomoxetine is known to be used and is
an inhibitor of the neurotransmitter, norepinephrine. It is not nearly as effective as stimulants but
it is still known to be a good option. It is usually used in kids who can’t tolerate stimulants or
have anxiety. Other antidepressants that can be used are bupropion and TCAs, which are
considered last choice options. Alpha agnostics like guanfacine and clonidine can be effective
for ADHD treatment. But they have multiple impacts such as lowering blood pressure, causing
sedation, dizziness, weight gain and more. They are typically better for children than adults
(Magnus et al., 2022).

Non-Pharmacological Treatment

Another treatment for ADHD is psychosocial treatment (Magnus et al., 2022). This includes
psycho-education for the family and patient and involves cognitive-behavioral training programs
designed specifically for the patient to obtain long and short-term goals. With pharmacotherapy,
these training programs have been proven effective (Magnus et al., 2022).
Misdiagnosis of ADHD

Manos, M. J., Giuliano, K., & Geyer, E. (2017). ADHD: Overdiagnosed and overtreated, or
misdiagnosed and mistreated? Cleveland Clinic Journal of Medicine, 84(11), 873–880.
Magnus, W., Nazir, S., Anilkumar, A. C., & Shaban, K. (2022). Attention Deficit
Hyperactivity Disorder. In StatPearls. StatPearls Publishing.


1. American Psychiatric Association. (2013). Diagnostic and statistical manual of mental
disorders (5th ed.).
2. Austerman, J. (2015). ADHD and behavioral disorders: Assessment, management, and
an update from DSM-5. Cleveland Clinic Journal of Medicine, 82(11 suppl 1), S2–S7.
3. Holland, J., & Sayal, K. (2019). Relative age and ADHD symptoms, diagnosis and
medication: A systematic review. European Child & Adolescent Psychiatry, 28(11),
4. Magnus, W., Nazir, S., Anilkumar, A. C., & Shaban, K. (2022). Attention Deficit
Hyperactivity Disorder. In StatPearls. StatPearls Publishing.

5. Manos, M. J., Giuliano, K., & Geyer, E. (2017). ADHD: Overdiagnosed and overtreated,
or misdiagnosed and mistreated? Cleveland Clinic Journal of Medicine, 84(11),
6. Sciberras, E., Mulraney, M., Silva, D., & Coghill, D. (2017). Prenatal Risk Factors and
the Etiology of ADHD-Review of Existing Evidence. Current Psychiatry Reports, 19(1), 1.
7. Xue, J., Zhang, Y., & Huang, Y. (2019). A meta-analytic investigation of the impact of
mindfulness-based interventions on ADHD symptoms. Medicine, 98(23), e15957.
8. Pliszka S; AACAP Work Group on Quality Issues. Practice parameter for the
assessment and treatment of children and adolescents with attention-deficit/hyperactivity
disorder. J Am Acad Child Adolesc Psychiatry. 2007 Jul;46(7):894-921.

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