5.2.2 ADHD

ADHD

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by inattention, hyperactivity, and impulsivity. ADHD affects about 5-10% of school-aged children, with symptoms persisting into adulthood in about 50-70% of cases.

ADHD is characterized by inattention, hyperactivity, and impulsiveness, with ICD-10 referring to these symptoms as hyperkinetic disorder. DSM-5 and ICD-11 recognize three subtypes: combined, inattentive (ADD), and hyperactive-impulsive. Symptoms must be developmentally inappropriate, present across time and situations for at least six months, and start before age 7 (DSM-5 criteria now state several symptoms present before age 12, allowing adult diagnosis). About 5% of UK schoolchildren meet DSM-5 ADHD diagnostic criteria, 1% meet ICD-10 hyperkinetic disorder criteria, and it is 2-3 times more common in males.

The controversy of ADHD: The concept of ADHD has sparked controversy, with critics arguing that it medicalizes a social issue rather than addressing the root causes. Some believe ADHD is over-diagnosed, undermining parental roles and attributing natural childhood behaviour to a disorder. The long-term benefits of medication are also debated, with questions surrounding their efficacy and potential side effects. Despite these concerns, there is a growing understanding that ADHD symptoms can persist into adulthood and may lead to adverse outcomes if left untreated. For many children and families who have experienced positive results from medication, the desire to continue treatment often outweighs the uncertainties surrounding long-term effects.

Prevalence/Incidence:

ADHD is one of the most common childhood disorders, affecting about 5-10% of school-aged children. Boys are more likely than girls to be diagnosed with ADHD, with a male-to-female ratio of about 3:1. ADHD symptoms often persist into adulthood, with estimates suggesting that 50-70% of cases continue to experience symptoms. In adults, the prevalence of ADHD is estimated to be around 2.5%.

ADHD is more common in males:

• male : female ratio in children = 2-5:1 (NICE CKS)
• male : female ratio in adults = 1-6:1

Aetiology:

The exact cause of ADHD is unknown, but both genetic and environmental factors are believed to play a role. Studies have found that ADHD is highly heritable, with a heritability estimate of around 70-80%, and the risk of ADHD in siblings is 2–3 times. Environmental factors such as prenatal exposure to nicotine, alcohol, or other toxins may also increase the risk of ADHD. Other risk factors include premature birth, low birth weight, and traumatic brain injury.

Presentation:

Behaviours and contexts:

ADHD can be associated with a range of behaviours, including self-harm, refusal to attend school, and oppositional defiant disorder (ODD). Self-harm may occur as a result of emotional dysregulation or impulsivity, while refusal to attend school may be due to academic difficulties or social problems. ODD is characterized by a pattern of negative, hostile, and defiant behaviour towards authority figures, and is often comorbid with ADHD.

ADHD may present differently in different contexts. For example, preschool-aged children with ADHD may exhibit more physical activity and difficulty following rules than their peers, while school-aged children may struggle with academic tasks and maintaining friendships. In adulthood, ADHD may manifest as difficulties with time management, organization, and executive functioning.

Treatments:

The main treatments for ADHD include medication and behavioural interventions. Stimulant medications such as methylphenidate and amphetamines are often used to manage ADHD symptoms, although non-stimulant medications such as atomoxetine may also be used.

Presently, drug therapies for ADHD offer symptomatic relief—they address the core symptoms without providing a cure. Around 70% of children with the condition will exhibit a symptomatic response to medication, as indicated by: increased focused behaviour; diminished restlessness, finger-tapping, and interruptions; decreased impulsivity; enhanced performance accuracy; lessened aggression; better compliance; ameliorated parent-child interactions; and a boost in peer status.

Prior to initiating medication, refer to cardiology if:

• There is a suggestion of cardiac pathology (history of heart disease, symptoms suggestive such as fainting, breathlessness, palpitations, or murmur)
• A history of sudden death in a first-degree relative under 40 years suggesting a cardiac disease

Medication guidelines:

• Methylphenidate or lisdexamfetamine are first-line (try one, if unsuccessful, consider the other)
• Consider dexamfetamine for those responding to lisdexamfetamine but who cannot tolerate the longer effect profile
• Offer atomoxetine for those who can’t tolerate methylphenidate or lisdexamfetamine due to side effects

Drug	Class	Indications	Side Effects
Methylphenidate	CNS stimulant	ADHD in children over 6 years	Abdominal pain, nausea, vomiting, dry mouth, anxiety, insomnia, dysphoria, headaches, anorexia, weight loss, growth suppression (monitoring advised)
Dexamfetamine/lisdexamfetamine	CNS stimulant	ADHD in children with refractory symptoms	Similar to those of methylphenidate
Atomoxetine	Non-stimulant NARI	ADHD	Anorexia, dry mouth, nausea, vomiting, headache, fatigue, dysphoria, jaundice (liver damage), suicidal thoughts
Guanfacine	Non-stimulant α2a receptor agonist	ADHD in children when stimulants are not suitable or tolerated	Sedation, hypotension, bradycardia, GI side effects, depression, mood lability, anxiety
Clonidine	α2 agonist (unlicensed for this use)	–	Hypotension, bradycardia, sedation, dizziness, risk of rebound hypertension if stopped suddenly

Medication monitoring:

• Most side effects tend to subside within a few weeks.

• Some concerns have arisen about minor growth limitations in children using psychostimulants. Consequently, certain children opt for ‘medication breaks’ to allow for growth catch-up.

• Stimulants often cause appetite suppression, so it is essential to closely monitor children’s weight and seek dietitian guidance if needed. Children and adolescents should be checked for height, weight, blood pressure, and pulse during the initial medication adjustment period and every six months thereafter, once a stable dose is achieved.

• If sleep problems occur, melatonin may prove beneficial for young individuals with neurodevelopmental issues.

Behavioural interventions such as cognitive-behavioural therapy (CBT) and parent training can also be effective in improving ADHD symptoms and associated behaviours.

Outcome:

The long-term outcome of ADHD varies depending on factors such as the severity of symptoms, comorbidities, and access to treatment. However, studies suggest that ADHD is associated with a range of negative outcomes, including academic difficulties, social problems, and increased risk of substance use disorders. Early diagnosis and intervention can improve outcomes for individuals with ADHD.

Subheading	Information
Prevalence/Incidence	ADHD is estimated to affect 5-7% of children and adolescents and 2-5% of adults. Boys are more commonly diagnosed than girls.
Aetiology	Genetic factors are believed to play a significant role in the development of ADHD. Environmental factors such as prenatal exposure to nicotine, alcohol, or other toxins may increase risk.
Presentation	Core symptoms include inattention, hyperactivity, and impulsivity. May also experience academic, social, and emotional difficulties.
Behaviours	May be associated with self-harm, refusal to attend school, and oppositional defiant disorder.
Contexts	May present differently in preschool, school-aged, and adult populations.
Treatments	The main treatments include medication and behavioural interventions such as CBT and parent training.
Outcome	Long-term outcomes depend on factors such as symptom severity, comorbidities, and access to treatment. Early diagnosis and intervention can improve outcomes.

An Understanding of How ADHD Relate to Behaviours (e.g. Self-harm, Refusal to Attend School etc.) and Contexts (e.g. Pre-school Behaviours)

Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that affects numerous aspects of a child’s life, including their behaviour and functioning in various contexts. ADHD is characterized by core symptoms such as inattention, hyperactivity, and impulsivity. These symptoms can manifest in different behaviours and have a significant impact on a child’s daily life, including self-harm, school refusal, and challenges in preschool settings.

Self-harm: Children with ADHD may struggle with emotional regulation and impulsivity, leading to a higher risk of engaging in self-harm behaviours. These behaviours can arise from feelings of frustration, low self-esteem, or difficulty managing overwhelming emotions. The impulsivity aspect of ADHD can also contribute to an increased likelihood of self-harm, as the child may act on the urge without considering the consequences.

Refusal to Attend School: ADHD can make it difficult for a child to cope with the demands of a structured school environment. Children with ADHD may struggle with organization, time management, and concentration, leading to academic underachievement and frustration. Additionally, they may experience social difficulties and have trouble forming positive relationships with peers and teachers. These challenges can contribute to school refusal, as the child may feel overwhelmed or anxious about attending school.

Pre-school Behaviors: ADHD symptoms can be particularly evident in preschool settings, where structured routines and social interactions with peers are significant components of the day. Young children with ADHD may exhibit disruptive behaviours, such as difficulty following instructions, excessive talking, or an inability to sit still. They may also struggle with emotional regulation, leading to outbursts or meltdowns. These behaviours can impact their ability to participate in activities, engage with peers, and develop essential social skills.

In conclusion, ADHD can have a profound influence on a child’s behaviour and ability to navigate different contexts. Early identification and intervention are crucial for addressing these challenges and fostering healthier emotional development and functioning. With appropriate support, therapy, and educational accommodations, children with ADHD can develop coping strategies and resilience, enabling them to better adapt to various situations and relationships.

References:

1. American Academy of Pediatrics. (2019). Clinical practice guideline for the diagnosis, evaluation, and treatment of attention-deficit/hyperactivity disorder in children and adolescents. Pediatrics, 144(4), e20192528.
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8. National Institute of Mental Health. (2021). Attention-deficit/hyperactivity disorder (ADHD). Retrieved from https://www.nimh.nih.gov/health/topics/attention-deficit-hyperactivity-disorder-adhd/index.shtml
9. Owens, E. B., Hinshaw, S. P., Kraemer, H. C., Arnold, L. E., Abikoff, H. B., Cantwell, D. P., … Swanson, J. M. (2019). Which treatment for whom for ADHD? Moderators of treatment response in the MTA. Journal of Consulting and Clinical Psychology, 87(6), 530-543.
10. Thapar, A., Cooper, M., Eyre, O., & Langley, K. (2012). Practitioner review: What have we learnt about the causes of ADHD? Journal of Child Psychology and Psychiatry, 53(1), 3-16.
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