Attention-Deficit/Hyperactivity Disorder (ADHD)

Inattention

At least 6 of the following symptoms have persisted for at least 6 months to a degree that is inconsistent with developmental level and that negatively impacts directly on social and academic/occupational activities:

1. Often fails to give close attention to details or makes careless mistakes in schoolwork, at work, or during other activities (e.g. - overlooks or misses details, work is inaccurate).
2. Often has difficulty sustaining attention in tasks or play activities (e.g. - has difficulty remaining focused during lectures, conversations, or lengthy reading)
3. Often does not seem to listen when spoken to directly (e.g. - mind seems else where, even in the absence of any obvious distraction)
4. Often does not follow through on instructions and fails to finish schoolwork, chores, or duties in the workplace (e.g. - starts tasks but quickly loses focus and is easily sidetracked).
5. Often has difficulty organizing tasks and activities (e.g. - difficulty managing sequential tasks; difficulty keeping materials and belongings in order; messy, disorganized work; has poor time management; fails to meet deadlines).
6. Often avoids, dislikes, or is reluctant to engage in tasks that require sustained mental effort (e.g. - schoolwork or homework; for older adolescents and adults, preparing reports, completing forms, reviewing lengthy papers).
7. Often loses things necessary for tasks or activities (e.g. - school materials, pencils, books, tools, wallets, keys, paperwork, eyeglasses, mobile telephones).
8. Is often easily distracted by extraneous stimuli (for older adolescents and adults, may include unrelated thoughts).
9. Is often forgetful in daily activities (e.g., doing chores, running errands; for older adolescents and adults, returning calls, paying bills, keeping appointments).

Hyperactivity and Impulsivity

At least 6 of the following symptoms have persisted for at least 6 months to a degree that is inconsistent with developmental level and that negatively impacts directly on social and academic/occupational activities:

1. Often fidgets with or taps hands or feet or squirms in seat.
2. Often leaves seat in situations when remaining seated is expected (e.g. - leaves his or her place in the classroom, in the office or other workplace, or in other situations that require remaining in place).
3. Often runs about or climbs in situations where it is inappropriate (Note: In adolescents or adults, may be limited to feeling restless.)
4. Often unable to play or engage in leisure activities quietly
5. Is often “on the go,” acting as if “driven by a motor” (e.g. - is unable to be or uncomfortable being still for extended time, as in restaurants, meetings; may be experienced by others as being restless or difficult to keep up with)
6. Often talks excessively
7. Often blurts out an answer before a question has been completed (e.g. - completes people’s sentences; cannot wait for turn in conversation).
8. Often has difficulty waiting his or her turn (e.g. - while waiting in line)
9. Often interrupts or intrudes on others (e.g. - butts into conversations, games, or activities; may start using other people’s things without asking or receiving per mission; for adolescents and adults, may intrude into or take over what others are doing).

• ADHD is likely overdiagnosed.^{[23][24][25][26][27][28][29][30]}
• It is important to be aware of diagnostic creep and overdiagnosis! True ADHD is a debilitating condition that presents largely in childhood and absolutely should be treated.
• However, we are likely in a culture of overdiagnosis right now, especially with the ease of prescribing stimulants and short assessments in primary care settings. A short or incomplete assessment means a thorough differential diagnosis has not been considered.
• Since individuals both with and without ADHD can experience improved attention and decreased restlessness while taking stimulants, medication response alone is not and cannot be the basis for diagnosing the disorder.^[31][32][33]
  • However, this is often a common diagnostic fallacy that most clinicians make.

• It is also important to note that the increase in ADHD diagnoses is multifactorial.
• Factors such as greater awareness of mental health, ADHD itself, and its treatments are contributors.
• Social factors, cultural factors, and the influence of pharmaceutical marketing also plays a role.
• Finally, insufficient diagnostic training (e.g. - diagnosis in primary care without a detailed psychiatric and developmental history assessment) and lack of resources devoted to non-pharmacological management of childhood behavioural problems may further compound the issue.

• Although many ADHD guidelines continue to suggest that prevalence rates are stable, and that overdiagnosis is not occurring, the epidemiological data is increasingly showing the opposite.
• A 2015 systematic review and meta-analysis (the most comprehensive to date) provided a conservative benchmark overall pooled estimate prevalence of 7.2% using 36 years of ADHD studies^[35]
• In the United States, from 1997 to 2016, the estimated prevalence of diagnosed attention-deficit/hyperactivity disorder in US children and adolescents increased from 6.1% in 1997 to 10.2% in 2016.^[36]
  • This far exceeds the baseline estimated prevalence rates from the systematic review, suggesting that overdiagnosis may be occurring.

Psychiatric

• Oppositional defiant disorder (ODD)
  • Children with ODD have distinct characteristics, including refusal to comply with rules, deliberately annoying others, blaming others for their own mistakes, and/or being spiteful or vindictive. Overlapping symptoms with ADHD include losing temper, anger, resentment, irritability, and argumentative behaviours
• Conduct disorder
  • The essential characteristic of conduct disorder is repetitive and persistent behavior such as violation of others' fundamental rights or of social rules/norms
• Disruptive mood dysregulation disorder (DMDD)
• Specific learning disorder
• Generalized anxiety disorder (GAD)
• Obsessive-compulsive disorder (OCD)
• Major depressive disorder (MDD)
  • A recent drop in mood is different from the lifelong demoralization that may be seen in ADHD. Moderate to severe depression should be treated first and suicide must be assessed in all cases
• Autism spectrum disorder (ASD)
  • Until the publication of the DSM-5, ASD was an exclusionary criterion in making the diagnosis of ADHD. Thus its relationship to ADHD remains poorly understood, between 30 to 70% of patients with ASD may meet criteria for ADHD
• Bipolar I disorder or Bipolar II disorder
  • Many symptoms of bipolar disorder overlap with ADHD symptoms (e.g. - insomnia, impulsive sexual behaviours, impulsivity), which can be diagnosis challenging. Bipolar disorder is distinct in that there is grandiosity, and episodic symptoms (versus chronic in ADHD)
• Personality disorders
  • Borderline personality disorder
    • The symptoms of impulsivity, mood dysregulation, and poor concentration/focus may be better explained by BPD.
• Psychotic disorders
• Substance use disorders

Medication-related

• Medication with cognitive dulling side effect
  • Think about mood stabilizers and antipsychotics
• Medication with psychomotor activation
  • Think about decongestants and beta agonists

Other Factors

• Unsafe or disruptive learning environment
• Family dysfunction or poor parenting
• Child abuse or neglect
• Attachment disorders
• Intellectual giftedness
  • Individuals with giftedness may be misdiagnosed with ADHD in two ways. They may have high energy and over-excitability in school contexts (particularly in those with little academic stimulation), or individuals may meet full diagnostic criteria for ADHD but are able to concentrate for long periods of time, thus may not be diagnosed with ADHD.

General Medical Conditions

• Sleep disorders
  • Insomnia disorder
    • Insomnia in both children and adults can cause decreased attention, difficulties in emotional and behavioural regulation, decreased cognitive functioning (e.g., poor memory), and worse academic performance. Thus, a careful sleep history should be done to rule out the impact of sleep on the individuals symptoms. Additionally, stimulants can worsen sleep, and it is important to monitor for this
  • Obstructive sleep apnea or central sleep apnea
    • Sleep apnea can mimic or aggravate ADHD symptoms, once sleep apnea is properly treated, ADHD symptoms may resolve on their own.^[54]
• Traumatic brain injury
  • Since underlying ADHD can increase risk for head trauma, it is important to look for timing of cognitive symptoms apparition (present before, or appeared or worsened after head trauma).
• Seizure disorders
  • Absence seizures where an individual appears to lose attention or focus may be misdiagnosed as ADHD.^[55]
  • Anti-epileptic medications side effects can impair attention and learning, may be confused with ADHD symptoms.
• Hearing impairment or vision impairment
  • Order audiology and vision assessment if there are any concerns
• Thyroid disorders
  • Order TSH levels to check for hypothyroidism or hyperthyroidism
• Hypoglycemia
  • Check blood glucose levels
• Anemia
  • Order CBC
• Lead poisoning
  • Order blood lead levels
• Fragile X syndrome (FXS)
  • Molecular genetic testing for the FMR-1 gene confirms the diagnosis of Fragile X.
• Phenylketonuria
• Neurofibromatosis
• Fetal alcohol spectrum disorder (FASD) and Intellectual disability
  • Consider the presence of intellectual disability and FASD by observing for growth deficiency and facial features and FASD. Ask a thorough developmental history around prenatal alcohol exposure risk. Further psychoeducational testing may also be helpful.

Psychoeducation involves discussing the impact of ADHD on day-to-day functioning, treatment options, and strategies for optimizing function. Psychoeducation can help empower patients and families by providing information on ADHD.^[56] It has been found to increase knowledge, enhance treatment adherence, and improve attitudes and intended behaviours towards the person with ADHD.^[57] Psychoeducation typically involves:

• Explaining the rationale for the diagnosis, referencing examples of symptoms and impairment given by the parents and child/adolescent
• Explaining that although ADHD has a genetic component, environmental interventions can still be immensely helpful
• Reviewing the natural course and prognosis of ADHD and discuss comorbid conditions
• Discussing available treatment options (both pharmacological and non-pharmacological)
• Conveying a message of hope and optimism, telling the patient and family that ADHD tends to improve over time and is among the most treatable of psychiatric disorders

1. Long-acting stimulants are preferred as first-line treatment agents.
   • There should be an adequate trial of both classes of long-acting stimulants before moving onto a trial of a second-line agent.
2. Short- and intermediate-acting stimulants, and non-stimulants (i.e. - guanfacine, atomoxetine) are second-line treatment agents, and can be used for patients who experience significant side effects on first-line agents, have had poor response on first-line, or do not have access to first-line medications^[69]
   • Second-line stimulants can additionally be used for:
     • As a PRN for certain activities, and/or
     • To augment long-acting formulations early or late in the day, or early in the evening
   • Second-line non-stimulants can also be used:
     • In combination with first-line agents as a potential augmentation for first-line treatment suboptimal responders
     • In patients where stimulants are contraindicated (e.g. - high risk of stimulant misuse or diversion)
3. Third-line treatments include agents such as bupropion, clonidine, imipramine, modafinil, and atypical antipsychotics. These medications are off-label use, and may be used in adjunct with other first or second line agents. These medications have higher risks, higher side-effect profile, or lower efficacy.
   • There is no significant difference between picking clonidine and guanfacine in terms of efficacy as an adjunct.

Having an approach to prescribing can help the clinician assess whether a medication is working, and provides a systematic approach to monitoring prescribing:

1. Start the medication on weekend so parents can see how the child responds to the drug throughout the day (not on a school day!)
   • Educating parents about the length of action of each medication is very important!
   • Children may appear “not be responding” because the effect of the medication has actually worn off by the time they come home from school
2. Wait approximately 1 week to see if they are having a good response to the medication before making any changes
   • This different than titrating an antidepressant where one might wait longer
3. Titrating the medication:
   • Start low and titrate the dose by small increments, and monitor closely
   • Continue the titration until one of these events happen:
     • Optimal response is achieved
     • Intolerable adverse effects develop
     • Maximum dose is reached
   • The trick is finding the “sweet spot” dose – not too low such that there is no effect, and not too high that it causes side effects
4. If there is non-response, also consider trying a different formulation in the same class (methylphenidate or amphetamine) before switching to another class.