ADHD

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Questions and Answers

What are common inattentive symptoms of ADHD in childhood?

Rides bicycles excessively

Likes to play quiet games

Has a heightened sense of awareness

Often loses things (correct)

Which demographic shows a higher prevalence of ADHD?

Children aged 5 to 10

Adults over the age of 60

Males at a ratio of 2.5:1 compared to females (correct)

A 1:1 male to female ratio

What percentage of children are estimated to be affected by ADHD?

1-2%

10-12%

4-6% (correct)

2-3%

Which of the following symptoms is indicative of impulsivity-hyperactivity in ADHD?

Often fidgets Signup and view all the answers

ADHD often persists into which stages of life?

Adolescence and adulthood Signup and view all the answers

Which of the following is not a common symptom of ADHD?

Ability to focus on multiple tasks at once Signup and view all the answers

What is a common emotional consequence of ADHD in individuals?

Increased risk of anxiety disorders Signup and view all the answers

Which neurotransmitter system is implicated in ADHD?

Catecholaminergic Signup and view all the answers

What is the initial intervention recommended for children and adolescents with ADHD symptoms that are impairing across more than one context?

Group-based ADHD-focused support Signup and view all the answers

Which medication is considered first-line treatment for adults with ADHD?

Methylphenidate Signup and view all the answers

What should be monitored before and during the treatment with stimulants for ADHD?

Heart rate and blood pressure Signup and view all the answers

Which stimulant medication primarily has therapeutic effects from its d-enantiomer?

Methylphenidate Signup and view all the answers

If a patient with ADHD does not respond to medication, what supportive intervention can be considered?

Cognitive Behavioral Therapy Signup and view all the answers

Which non-stimulant medication is indicated for ADHD after stimulants?

Guanfacine Signup and view all the answers

What effect do stimulants like methylphenidate typically have on appetite?

Decrease appetite Signup and view all the answers

Which of the following does NOT typically occur as a co-condition with ADHD?

Autism Spectrum Disorder Signup and view all the answers

What primarily modulates activity within the fronto-striatal networks associated with ADHD?

Dopamine and Norepinephrine Signup and view all the answers

Which of the following is NOT listed as an environmental risk factor for ADHD?

Excessive screen time Signup and view all the answers

Which part of the brain is primarily involved in the synthesis of dopamine?

Substantia nigra pars compacta Signup and view all the answers

Which of the following statements about ADHD neurobiology is correct?

Fronto-striatal networks show functional changes in ADHD. Signup and view all the answers

The mesocortical and mesolimbic dopaminergic pathways are primarily involved in which functions?

Emotional aspects and executive functions Signup and view all the answers

Which neurotransmitters are involved in the GABA-glutamatergic circuits associated with cognitive regulation?

Glutamate and GABA Signup and view all the answers

What type of circuits connect different parts of the cortex to the basal ganglia and thalamus?

Cortico-striatal loops Signup and view all the answers

Which condition is associated with premature birth as an ADHD risk factor?

Obstetric complications Signup and view all the answers

How do dopamine (DA) and norepinephrine (NE) influence prefrontal cortex (PFC) functions?

DA reduces noise in glutamatergic circuits, while NE enhances signal. Signup and view all the answers

What is the consequence of both excessive and insufficient catecholamine release on PFC functions?

Negative impact on cognitive functions Signup and view all the answers

What is suggested by studies regarding striatal dopamine transporter (DAT) binding in those with ADHD?

Inconsistencies may relate to previous stimulant treatments. Signup and view all the answers

Which mechanism is primarily responsible for the weakening of inappropriate connections in the brain?

DA increase in cyclic adenosine monophosphate (cAMP) signaling. Signup and view all the answers

What role do candidate gene studies play in ADHD pathophysiology?

They confirm the role of genetic factors in ADHD. Signup and view all the answers

Which of the following is a primary management strategy for preschoolers with ADHD?

ADHD-focused group parent training. Signup and view all the answers

What is the effect of chronic stimulant treatment on striatal DAT levels?

It may induce persistent DAT blockade. Signup and view all the answers

What is a significant factor influencing optimal frontal brain activity?

The balance of both dopamine and norepinephrine. Signup and view all the answers

Which of the following MRI modalities was primarily used to identify predictors of treatment response in ADHD?

Functional connectivity analysis Signup and view all the answers

What type of drug was involved in the treatment response studies mentioned?

Methyphenidate (MPH) Signup and view all the answers

What was linked to the clinical response two months after patients received treatment?

Baseline pre-treatment brain characteristics Signup and view all the answers

Which group exhibited more brain alterations in comparison to the other in the study?

ADHD group versus healthy controls Signup and view all the answers

The study utilized machine learning techniques primarily for what purpose?

Combining biological and clinical characteristics for predictions Signup and view all the answers

What specific characteristic was enriched for biologically plausible genes in the study?

Cortical differences Signup and view all the answers

What was the primary aim of the longitudinal neuroimaging study discussed?

To identify biological predictors of treatment response in ADHD Signup and view all the answers

What type of analysis did the study conduct related to structural connectivity?

Virtual histology Signup and view all the answers

What effect do stimulants have on the default-mode network (DMN) during tasks?

They decrease its activation. Signup and view all the answers

What role do catecholamines play in the effects of PH and amphetamines on the brain?

They affect decision-making and reward processing. Signup and view all the answers

What has been observed in early structural MRI studies regarding stimulant treatment in children with ADHD?

Attenuation of grey matter volumetric alterations. Signup and view all the answers

What is the evidence regarding chronic stimulant treatment's effect on brain function?

It shows inconclusive evidence of function improvement after wash-out. Signup and view all the answers

What changes do stimulant medications cause in brain functional connectivity during tasks?

They enhance connectivity of fronto-striatal/parietal networks. Signup and view all the answers

What preliminary evidence was found in diffusion imaging studies regarding treated vs untreated individuals with ADHD?

Subtle white matter differences between the two groups. Signup and view all the answers

What contradictory findings have emerged regarding stimulant treatment effects?

Some studies do not support the brain structure-related effects of treatment. Signup and view all the answers

Study Notes

Attention-Deficit Hyperactivity Disorder (ADHD)

ADHD is a neurodevelopmental disorder characterized by inattention, impulsiveness, and hyperactivity.
Core symptoms include problems with attention, impulsivity, and hyperactivity.
ADHD presents in two main domains: inattention and hyperactivity/impulsivity.
Three presentations exist: inattentive, hyperactive/impulsive, and combined type.
Inattention symptoms in adults (at least 5/9): failing to pay attention to details, difficulty concentrating, not seeming to listen, not following instructions, difficulty organizing tasks, avoiding tasks requiring effort, easily distracted, forgetfulness.
Hyperactivity/Impulsivity symptoms in adults (at least 5/9): fidgeting, inability to stay seated, feeling restless, talking excessively, difficulty awaiting turn, interrupting others.
ADHD often persists into adolescence and adulthood with often different symptoms.
Prevalence in children is 4-6%, and in adults 2-3%.
The male-to-female ratio in childhood/adolescence is approximately 2.5:1.

Outline of Presentation

Clinical presentation of ADHD
Catecholaminergic neurotransmission (a recap)
Catecholaminergic dysfunction in ADHD
Management of ADHD
Stimulant mechanisms of action
Stimulant effects on the brain
Non-stimulant medication
Predicting treatment response

Prevalence and Demographic Differences

Prevalence of ADHD is similar across different socioeconomic regions (LMIC and HIC).
No significant differences observed in prevalence between LMIC and HIC regions.
4-6% of children exhibit ADHD, whereas 2-3% of adults show ADHD symptoms.
2.5 to 1 male-to-female ratio in children and adolescents (referral bias).
ADHD persists in adolescence (50-80%) and adulthood (30-50%), but the symptoms may change.

Adult Life

Symptoms of ADHD usually decline with age.
Functional impairment associated with ADHD decreases over time.
Approximately 15% of diagnosed ADHD cases persist with full diagnostic criteria in adulthood.

Clinical Cases

Presented with detailed examples of case studies, which included various ages and presentations of ADHD.

ADHD and Everyday Life

ADHD is associated with negative outcomes, including:
Academic problems
Employment problems
Risk-taking behaviours
Addictions
Health problems (obesity, etc.)
Emotional and conduct problems (bullying, criminal behaviours)
Teen pregnancies

Diagnosis of ADHD

Requires observable symptoms in multiple settings (e.g., home, school, etc.) for at least six months.
Symptoms emerge primarily during early to mid-childhood.
No single biological marker exists.
Psychologists use a combination of psychiatric interviews & collateral information (e.g., school reports)
Rating scales and neuropsychological test results support the clinical assessments.

Etiology of ADHD

The liability threshold model suggests both genetic and environmental factors determine ADHD.
Neither factor alone is sufficient to cause ADHD; accumulation of risk factors leads to symptom manifestation.
Genetic factors include polygenic risk, familiarity, and a p-factor.
Environmental factors include toxins (including alcohol and nicotine exposure during pregnancy), nutritional deficiencies, obstetric complications, low birth weight, premature birth, maternal hypertension, obesity, stress levels, and infections.

Neurobiology of ADHD

ADHD correlates with structural and functional differences that are primarily present in the fronto-striatal networks (and also the parietal and cerebellar regions).
These areas play key roles in functions like attention, inhibition, motivation, and emotion.
Catecholaminergic pathways (dopamine and norepinephrine) are essential in these brain processes.

Catecholaminergic pathways

Dopamine and norepinephrine are key neurotransmitters impacted in ADHD.
Activity within these networks is modulated by dopamine (DA) and norepinephrine (NE).
The areas in which these neurotransmitters are released have a direct impact on functions such as concentration and attention.

Cortico-striatal loops

These loops consist of GABAergic and glutamatergic circuits.
These pathways are modulated by dopamine.
Involved in motor planning, cognitive functions, and emotional processing.
Function disruption can explain the symptoms of ADHD.

Stimulant effects on brain regional structure and function

Early MRI studies show that stimulant treatment can attenuate or eliminate early grey matter differences in ADHD.
Further studies on chronic treatment showed inconsistent results, showing no conclusive evidence for longer-term brain functional improvement.

Stimulant effects on brain structural and functional connectivity

Emerging evidence suggests stimulant treatments influence brain activity and connectivity patterns.
Stimulant treatments can enhance connectivity of task-related brain regions and reduce connectivity of default mode brain networks.

Non-stimulants

Atomoxetine is a selective norepinephrine reuptake inhibitor.
It reduces NE reuptake (primarily in the prefrontal cortex).
Guanfacine is selective alpha-2A receptor agonist. It modulates norepinephrine effects within the prefrontal cortex.

Predictors of Treatment Response

Neuroimaging studies try to identify biological predictors of treatment response in adults with ADHD
Using different types of neuroimaging (MRI, fMRI, PET, and others) helps identify specific brain structures or functions that might predict who responds well to treatment or not in adults with ADHD. Brain connectivity patterns can predict treatment response.

Management of ADHD (NICE Guidelines)

Pre-schoolers (< 5 years): ADHD-focused parent training programs are an initial step. Consider medication if symptoms persist across multiple domains.
Children and adolescents (≥ 5): Consider medication, such as methylphenidate, lisdexamfetamine, or atomoxetine/guanfacine if symptoms persist across multiple domains. Consider additional support if symptoms related to Oppositional Defiant Disorder or Conduct Disorder co-occur.
Adults: Consider medication (methylphenidate, lisdexamfetamine or dexamphetamine, atomoxetine) in order; Consider supportive psychological interventions if medication is ineffective.

Indication for ADHD meds

Stimulants (methylphenidate, Ritalin, Concerta) are often first-line treatment for moderate to severe impairment.
Other options (lisdexamfetamine, atomoxetine, guanfacine) might also be considered.

Cautions/Side Effects of ADHD medication

Stimulant medication may increase blood pressure and heart rate.
Stimulants can sometimes impact appetite and sleep patterns.
Regular monitoring of blood pressure, heart rate, height, and weight during treatment is appropriate.

Different formulations of Methylphenidate Medication

Different formulations exist for methylphenidate, offering variable release patterns. This helps maintain optimal medication levels throughout the day.

MPH vs Amphetamines

Methylphenidate and amphetamines (and their derivatives) are both stimulants.
D-enantiomer of methylphenidate is responsible for most effects (unlike amphetamines).
Methylphenidate directly and indirectly affects the release of dopamine and/or norepinephrine in the brain.

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Description

Test your knowledge about Attention Deficit Hyperactivity Disorder (ADHD) focusing on its symptoms, prevalence, and treatment options. From common symptoms in children to management strategies for adults, this quiz covers the key aspects of ADHD. Perfect for students and professionals looking to enhance their understanding of this condition.