Do we know what causes ADHD?

The precise causes of ADHD in individual cases currently remain unknown. Research has indicated that ADHD is hereditary, however, the responsible genes are not yet identified.

Prenatal and early-life exposures, including brain injury, toxins like lead, and maternal substance use (especially alcohol and tobacco), have also been linked to causes of ADHD. Premature birth and low birth weight are also identified risk factors. Contrary to popular belief, evidence does not support notions that ADHD arises solely from lifestyle factors like excessive sugar consumption or screen time.

The line between normal and ‘abnormal’ behaviour is often blurred and subjective, with many children who have other emotional or behavioural concerns also showing signs of core ADHD symptoms.

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What is ADHD?

Attention deficit hyperactivity disorder (ADHD) is a behavioural condition characterised by core experiences of hyperactivity, impulsivity, and inattention.

Some children or adults diagnosed with ADHD are predominantly hyperactive and impulsive, while others are mainly inattentive.

This neurodevelopmental condition can significantly impact various aspects of daily life. Some aspects include academic or workplace performance, social interactions, and emotional well-being. Recognising the diverse presentations of ADHD is crucial for accurate diagnosis and tailored interventions to support individuals and families affected by this condition.

Who is affected by ADHD?

ADHD symptoms typically emerge before the age of 6 and are observable in multiple settings, such as home and school. ADHD is diagnosed more frequently in boys than in girls, however awareness of ADHD in girls is increasing. It is not a condition that goes away with age, so people of all ages can be affected by ADHD, which is why many adults are also seeking diagnosis in recent years.

The signs of ADHD manifest in various behavioural patterns. They are categorised into two primary types: inattentiveness and hyperactivity/impulsiveness. While many people with ADHD experience challenges encompassing both categories, some may exhibit symptoms predominantly from one type.

How is ADHD diagnosed?

ADHD diagnosis involves a comprehensive assessment process conducted by healthcare professionals.

Two diagnostic criteria are in current use:

  • The International Classification of Mental and Behavioural Disorders 11th revision (ICD-11): This diagnostic criterion uses a narrower diagnostic category.
  • The Diagnostic and Statistical Manual of Mental Disorders 5th edition (DSM-V): DSM-V has a broader, more inclusive definition, which includes several different ADHD subtypes.

Definitive diagnosis requires the presence of symptoms before a child reaches seven years. The symptoms must:

  • continue for at least six months
  • occur in more than one setting (for instance at home, school, or with friends)
  • cause significant functional impairment
  • cannot be better explained by another psychiatric childhood condition

Diagnostic tools are used, such as questionnaires and psychometrics. They ask questions of the parents, school, and even the child (depending on their age). A detailed history will be taken to understand the child’s development and challenges. The Psychiatrist or other health professional will also spend time with the child to observe their behaviours first-hand.

How to tell the difference between ADHD and naughty behaviour

ADHD differs from naughty or boisterous behaviour in that children with ADHD can struggle with inattention, daydream, may be disorganised and might often lose things.

Children with hyperactivity problems seem to be on the go all the time and are typically restless and talkative. Although many children show some disruptive behaviour as part of growing up, those with ADHD have behavioural difficulties that disrupt their lives and can disrupt the lives of those around them.

A key consideration in differentiating naughty or boisterous behaviour from core signs of ADHD is the degree of functional issues across multiple contexts and the degree to which these concerns interfere with a child’s development.

Ready to seek an ADHD diagnosis?

An ADHD diagnosis can allow children and adults to get the educational support they may need. At Clinical Partners, our mental health specialists are here to support you and your family.

Contact us now at 0203 326 9160.

As the UK’s largest private mental health partnership, we're dedicated to supporting children, adults, families, and organisations nationwide. Let's start your journey towards clarity and support today.

Clinically reviewed

  • Amy Mowson
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