Therapy focus: ADHD

Attention deficit hyperactivity disorder (ADHD) is a complex neurobiological condition which, globally, affects about 5.3 per cent of the population, 2-6 per cent of pre-school children and 6-13 per cent of adolescents. Some people think that children grow out of ADHD, but research shows that symptoms can remain relatively stable into adulthood. In fact, ADHD affects about 2 per cent of the world's adult population and as many as 65 per cent of children with ADHD may still have symptoms as adults.

ADHD is a psychiatric disorder with symptoms of inattention and/or impulsivity and hyperactivity that are more frequent and severe than in other people at the same level of development. ADHD impacts upon many areas of everyday life, affecting not only the patients themselves, but also their families and carers.

The majority of children with ADHD experience problems in their school, social and home lives, leading to educational underachievement and difficulty in making and keeping friends. As the condition often results in disruptive behaviour in the classroom, teachers are often best placed to identify ADHD when a child starts school.

In a review of 340 studies, untreated ADHD was shown to have a substantial, long-term, negative impact on all major areas of life, including schooling, work/employment, behaviour, social functioning, self esteem, health and public services use.

Cost in numbers
A conservative estimate of the annual societal cost of illness for ADHD in children and adolescents globally was €31.5bn, based on a prevalence rate of five per cent in 2005. This figure was calculated by researchers in a study published in 2007 in Ambulatory Pediatrics. They also calculated that, on an individual basis, the estimated annual cost of illness for ADHD in children and adolescents was approximately €10,800 in 2005.

At school, children with ADHD:

• Tend to have problems with academic achievement and are more likely to drop out or be at the bottom of the class
• Are at more than 100 times greater risk of being permanently excluded from school than other children; the impact of exclusion has shown to increase the likelihood of criminal behaviour
• Have been shown to have lower language, mathematics and reading scores
• Are more likely to repeat years, have fewer years of total schooling and are less likely to gain university or college degrees.

Around two-thirds of young offenders and up to half of the adult prison population have ADHD. Crimes committed by people with ADHD are estimated to cost society between €1.4-2.8bn per year.

People with ADHD are more likely to be unemployed than people without ADHD. According to a Norwegian study, published in the Journal of Attention Disorder in 2009, only 24 per cent of ADHD patients reported being in work, compared to 79 per cent in the control group.

Cause
Over the last hundred years, as technology has progressed and understanding of the brain and central nervous system has improved, the understanding of the aetiology for ADHD has changed dramatically.

It is important to separate myth from fact. Parenting and discipline styles do not cause ADHD and the influence of food additives on ADHD has not been sufficiently established.

While the exact origin of ADHD is not known, scientists speculate that the disorder may be caused by an imbalance of neurotransmitters (or chemicals in the brain) believed to play an important role in the ability to focus and pay attention to tasks. The consensus is that ADHD results from complex interactions between genetic and environmental factors.

Studies estimate that genetic effects account for 80 per cent of ADHD symptoms, and several genes that may largely be associated with ADHD have been identified, reinforcing the view that ADHD may be caused by a problem in the growth and development of the brain or central nervous system.

More males than females are seen to have ADHD. However, there are differences in how ADHD-related problems appear in girls. For instance, when compared to boys with ADHD, girls are less likely to demonstrate comorbid disruptive behaviour disorders and learning disabilities. This could mean that diagnosing ADHD in girls is either delayed or never happens.

Diagnosis
Diagnosing ADHD is a complex process involving recognition of symptoms and classification into a subtype using approved diagnostic criteria, tools and assessment scales.

Throughout most of the EU, diagnosis can only be made by a specialist and requires a full review of symptoms (see below).

 

Due to a lack of specialists in this area and the complex diagnostic criteria, ADHD can be extremely challenging to diagnose.

• In Europe, it takes, on average, more than two years (almost 27 months) for parents to reach a diagnosis of ADHD for their child – using DSM-IV criteria (see below)
• Almost two out of every five (38 per cent) parents need to see three or more doctors before receiving a diagnosis for a child with ADHD.

This delay in diagnosis has a significant impact, because a child's time in school is limited. The window of opportunity to act lasts for only a finite duration, because years lost before a diagnosis is made and treatment is started are years of learning that cannot be regained.

What makes an ADHD diagnosis even more complex is that many children, adolescents and adults with ADHD also have other co-existing (or comorbid) behavioural or psychiatric disorders. More than 85 per cent of ADHD patients have at least one other behavioural or psychiatric condition and approximately 60 per cent of patients have at least two other conditions. These conditions may overlap with ADHD and complicate the specialist's ability to diagnose and prescribe the right treatment.

The key diagnostic criteria tools currently used to identify ADHD are the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV-TR), published by the American Psychiatric Association (APA), and the International Classification of Mental and Behavioural Disorders, 10th revision (ICD-10), published by the World Health Organisation.

To be diagnosed with ADHD, the person needs to demonstrate:

• At least six of nine symptoms of inattention, one of four symptoms of impulsivity and three of five symptoms of hyperactivity according to the ICD-10 or at least six of nine symptoms of inattention, and/or at least six of nine symptoms of hyperactivity/impulsivity according to the DSM-IV-TR
• A persistent pattern of inattention and/or hyperactivity-impulsivity that is more frequent and severe than in individuals at the same level of development
• Symptoms that have been present for at least six months
• Some symptoms that were present before the age of seven
• That impairment from the symptoms is present in two or more settings – for example, at school or work and at home
• Clinically significant impairment in social, academic or occupational functioning
• Symptoms that cannot be better explained by another psychiatric disorder.

Treatment
Treatment and interventions for children and young people with ADHD are varied and provided in a range of settings. The specific treatment used will depend on the patient's symptoms and on his or her response to each type of approach.

Although ADHD has no cure, experts agree that a combination of medication, behavioural modifications and teaching support is the most effective at managing the inattention, hyperactivity and impulsivity symptoms associated with it.

Medication
For many people, medication is an important part of their treatment to manage their ADHD. It is, however, important to note that medication for children and adolescents with ADHD should be given only as part of a comprehensive treatment plan that includes psychological, behavioural and educational advice and interventions.

Evidence shows that medication alone, or in combination with behavioural therapy, gives more positive results than behavioural therapy alone. In a recent review of 340 studies, pharmacological treatment alone – or in combination with non-pharmacological treatments – was responsible for 98 per cent of outcomes stabilised or improved, compared with untreated ADHD.

The most commonly prescribed ADHD medications are from a class of drugs called stimulants – comprised of two main types: methylphenidate and amphetamines – although non-stimulants are also effective.

Stimulants are thought to enhance the availability of two of the brain's chemical messengers to help correct a presumed chemical imbalance in the brain. In numerous studies, stimulant medications have been proven to reduce symptoms such as inattention, impulsivity and hyperactivity and improve physical co-ordination and the ability to focus, work and learn.

Although parents may be worried that treatment with a stimulant could lead to drug abuse in later life, in fact the opposite seems to be true. Children diagnosed early and treated effectively with stimulant medication are less likely to go on to abuse substances, when compared with children with untreated ADHD.

Children taking stimulant medication for their ADHD have been shown to demonstrate increased accuracy and productivity, academic efficiency, and decreased disruptive behaviour. The most common side effects of stimulant medication are nervousness, headache and insomnia.

Non-stimulants are viable alternatives for ADHD patients who do not respond to stimulant treatment, do not tolerate stimulant medicines well or have decided against treatment with stimulants for personal, non-medical reasons.

The most commonly prescribed non-stimulant is atomoxetine. It is believed to work by increasing the amount of noradrenaline (one of the brain's chemical messengers), which helps manage the symptoms of ADHD by increasing attention span and reducing impulsive behaviour and hyperactivity. The most common side effects of atomoxetine are decreased appetite, headache, abdominal pain, vomiting, sleepiness and nausea.

Psychological therapies
All psychological interventions for ADHD aim to improve patients' daily functioning by improving their behaviour and relationships with family, friends and peers.

Psychological interventions can be used to:

• Limit difficult behaviour  
• Provide a sense of self-worth and achievement  
• Reduce the frustration of family members, care givers and other people with whom the patient interacts.

Depending on a person's needs, behavioural approaches used to help manage ADHD include cognitive behavioural therapy (CBT), social skills training and family therapy.

Teaching support
As school is often the place where the challenges faced by children with ADHD are first recognised, the joint role of the parent and the teacher is critical. An example of a resource providing teaching support is the ADHD Partnership Support Pack that has just been launched for use by teaching/educational networks, family organisations and ADHD advocacy groups. It has been developed by Shire Pharmaceuticals in collaboration with ADHD Europe and an expert European ADHD Awareness Taskforce.

Combination therapy
Combining pharmacological and psychological approaches may have the potential to deliver both immediate effects on ADHD symptoms through medication and more long-lasting effects through the development of behavioural and cognitive skills and strategies.

The future
ADHD is a diverse condition where every person with the disorder is different, the consequence of which is that treatment decisions for ADHD are complex.

As such, every person with ADHD should receive care that is tailored to his or her specific needs and preferences. To achieve this, patients and the healthcare professionals treating them need access to a wide range of therapeutic options, including medicines, which address the complexities of ADHD management.

A pan-European survey, published in Child and Adolescent Psychiatry and Mental Health in 2008, highlighted the importance of treatments that provide consistent control of ADHD symptoms throughout the full active day, outside the school environment. However, not all stimulants are currently licensed in Europe for the treatment of ADHD. In particular, amphetamines are not available in most European countries.

To date, the personalised, multimodal treatment approach which combines medication, behavioural modifications and teaching support remains the most effective, as it is more likely to meet the specific needs of individuals, by taking a variety of factors into account over time.

The Author
Eugene Osei-Bonsu is international marketing director at Shire