Diagnosis of ADHD in childhood

By Dr Linda Kelly

Attention Deficit Hyperactivity Disorder (ADHD) is a common neurodevelopmental disorder, often first diagnosed in early childhood. Population surveys estimate a prevalence rate of around 5% for children although the rate may be higher depending on the area surveyed. It’s considered to be a lifelong condition, and recent research has focused on how ADHD presents differently across the lifespan.

Know the criteria
According to the Diagnostic and Statistical Manual (DSM) V Manual of Psychiatric Conditions, the diagnosis is based on the essential occurrence of inattentive symptoms and (or) hyperactive impulsive symptoms that significantly interfere with daily functioning and development. Some of the symptoms need to be present before 12 years of age, and they need to occur in more than one setting.

There are, as yet, no specific diagnostic tests for ADHD such as blood tests, brain scans or EEGs. The diagnosis is made by taking a careful clinical history of the child’s symptoms from the caregivers, as well as information from teachers, therapists and anyone else who knows the child well.

Psychological and educational testing may be able to assist in confirming the symptoms but are not diagnostic in themselves. They’re useful because they demonstrate how ADHD symptoms are affecting behavioural and educational functioning and may also highlight any learning difficulties or disabilities.

There are a number of rating scales available which can be given to teachers, parents and therapists to confirm symptoms and also demonstrate changes in symptoms once treatment has been commenced.

Spot the signs
Inattentive symptoms include distractibility, losing focus, disorganisation, daydreaming, and forgetfulness, not listening to or following through on instructions, poor planning and losing belongings. Tasks of low interest to the child are often the hardest to focus their attention on. This often includes school work, but not technology and TV.

Hyperactivity symptoms include restlessness, inability to sit still, fidgetiness, noisy behaviour, excessive talking and being ‘on the go’. Children may run or climb when it’s not appropriate or fidget and move constantly in their seats in the classroom.

Impulsivity symptoms comprise of both behaviour and speech which aren’t properly thought through, intolerance of frustration, social intrusiveness, interrupting others and impatience. This behaviour may lead to the child experiencing unanticipated consequences because of a lack of thought before acting or speaking. These symptoms often cause a great deal of distress because the child receives a lot of negative feedback.

ADHD sub-types
There are 3 sub-types of ADHD. Some children have a predominance of one of these types of symptoms. For example, inattentive symptoms are more prominent in girls and may be missed for longer than in those children who have mainly hyperactive or impulsive symptoms, which are more common in boys.

The biggest proportion of children have a combination of all three groups of symptoms known as the combined sub-type of ADHD.

There’s also a range of severity of symptoms from mild to severe and this, together with the degree the symptoms cause difficulties in daily functioning, would play a role in determining what type of treatment is appropriate the child.

Co-morbid conditions
A very important issue in the diagnosis of ADHD is that of other conditions – both psychiatric and medical – that may present with some of the symptoms and look similar. Inattention itself isn’t a diagnosis but may be a symptom in many other conditions. It’s therefore very important to assess the child’s physical health to exclude conditions that could present in a similar way.

Just as importantly, it’s necessary to assess whether there are any other psychiatric disorders present, because this is very common, more the rule than the exception. These other conditions will need to be diagnosed and treated alongside ADHD, sometimes being the more prominent condition and needing treatment first.

In summary, ADHD is a common neuro-developmental condition. Early and accurate diagnosis can prevent many of the complications that may develop if the condition isn’t recognised.