Attention Deficit Hyperactivity Disorder (ADHD)

Managing and assessing children with Attention Deficit Hyperactivity Disorder (ADHD) requires input from a number of people involved with the child's care. Dr Sarah A El-Neil and Dr Mark Beattie outline its management

Hyperactivity in childhood is common. It is a disorder when it interferes with normal social function, learning and development. In this setting the diagnosis of ADHD has to be considered. ADHD is a neurodevelopmental disorder characterised by hyperactivity, inattention and impulsivity, features which need to be present in more than one setting. The condition is more common in boys than girls and it is not usually diagnosed in children under the age of seven years. It can occur without the hyperactivity.

Prevalence

ADHD is a heterogeneous condition with inter-observer variability in case definition. In the US, the threshold for diagnosing ADHD is lower and thus the prevalence of the condition is higher. Prevalence rates vary between 0.5 and 5 per cent of the total childhood population.

Aetiology

This is multifactorial. Many of the behaviour traits are extreme versions of normal seen in most children at some stage during their childhood. Many factors interplay in the causation. Some attribute the condition to over stimulation of children in a modern environment. There is no doubt that early childhood attachment problems and adverse family influences are a factor. However, the very high concordance in twins seen in genetic studies suggests a polygenic basis for inheritance. This implies an organic component to the disorder that many view as primary brain dysfunction.

Clinical features

The clinical features associated with ADHD are listed in Table 1. Associated problems in children with ADHD include poor self-esteem, antisocial behaviour, difficulties with peer group interaction and under achievement at school. ADHD can co-exist with specific learning disability, anxiety, depression, nocturnal enuresis and conduct disorders.

Assessment

This should be by different professionals and in different settings. The condition may be first suspected by the schoolteacher. The assessment needs to be co-ordinated by a doctor with special expertise in the condition, usually a child psychiatrist or community paediatrician. This strategy allows for a complete and accurate assessment of behaviour and helps emphasise that any management strategy needs to be consistent and agreed by the various professionals involved, particularly the school teacher. It is essential that the child and parents be involved at all stages. GPs need to refer any children who exhibit the symptoms listed in Table 1.

Rating scales are often used looking at different behaviours, for example: restless or over-activeÑnot at all, just a little, quite a lot, very much. Other parameters, which can be assessed in this way are listed in Table 2. There are various rating scales including the ConnorÕs parents and teachers rating scale (as described in Table 2) and the strengths and difficulties questionnaire. It is essential that the rating scale is only part of an overall thorough assessment, which includes a full history, examination and investigations if appropriate.

Differential diagnosis

It is important that children in whom ADHD is suspected are carefully assessed and other diagnosis considered. Hearing loss or specific learning disability (including auditory processing difficulties, dyspraxia, fragile X) needs to be excluded. Other differentials include epilepsy, autistic spectrum disorder (including AspergerÕs), thyroid disease (hypo- or hyper-thyroidism), drug ingestion, anxiety and depression. Factors such as lack of sleep, low self-esteem, poor social skills, difficult home environment and child abuse may be relevant. It is important to remember that some of the above can either co-exist or be complications of ADHD. Adverse environmental influences may be suspected when the parent or carer tells you that the behaviour is difficult in one setting (such as home) but not in other settings (such as school). It does not have to be home that is the adverse environment.

Management

Behavioural. Behavioural approaches include positive reinforcement, appropriate reprimands and the setting of simple achievable goals. It is important to be firm but fair. Teachers have a vital role to play and extra help is often required in the classroom. Behavioural therapies require proper supervision and need to be applied consistently with careful monitoring of the response by parents and teachers; parents need ongoing support for management in the home setting and family therapy may be required in difficult cases. Older children may benefit from formal cognitive-behavioural therapy to help with improving anger management, self-control, peer group relationships and self-esteem.

Medication. This is often used in combination with behavioural management. Methylphenidate (Ritalin) is the most commonly used drug. It is a controlled drug and works as a central stimulant promoting attention and bringing about more focussed behaviour. There are significant side-effects (see Table 3) and the drug should therefore be used with caution and its effects closely monitored.

Many studies have shown positive effects of stimulant medication in most children with ADHD. Use of stimulant medication improves not only school performance but often family and social functioning as well. It is most effective in a stressed environment and so there may be a greater improvement in the child's functioning in the school setting than the home setting.

The side-effects can be minimised by giving the drug only on school days and avoiding weekend and holidays. The duration of action of each dose is about four hours. This means doses can be given first thing in the morning and at lunch time if necessary in order to minimise the sleep disturbance. There is very little evidence for either long-term tolerance or addiction occurring. The usual starting dose is 5mg/day working up to 20-40mg/day. The medication is given two to three times a day; higher doses are occasionally used. Other drugs used include dexamphetamine.

Diet and additives. This works for some children. The evidence for it as a first line strategy is, however, quite slim. It is essential if a child's diet is restricted that it is under the supervision of a paediatric trained dietician in order that the child's diet is nutritionally adequate despite the exclusions. There are advocates of a few-foods diet in highly selected cases. It may be that reducing the additives in a child's diet makes it plainer and more balanced. This means less sweets and convenience type snack food. Making the diet more organised in this way may be a behavioural therapy in itself.

Prognosis. Untreated children with ADHD have a higher incidence of conduct disorders and delinquency in adolescence with a higher risk of educational underachievement, drug and alcohol dependency and criminal activity in adult life. Long-term behavioural therapy and medication can significantly improve the long-term prognosis. Treatment may need to be continued into adult life.

Conclusion

ADHD is a common condition. The diagnosis should be suspected in children in whom hyperactivity, impulsiveness and inattention are interfering with normal social functioning. Advice from the child's school is helpful. The response to therapy, including medication is good and such children should be referred to the local child health services for assessment and management.

Sarah A El-Neil is Specialist Registrar in Paediatrics; Mark Beattie is Consultant Paediatrician, Peterborough District Hospital

Further reading

Bramble D, Pearce J. Attention Deficit Hyperactivity Disorder: a rational guide to paediatric assessment and treatment. Current Paediatrics 1997; 7: 36-41
Hill P. Attention Deficit Hyperactivity Disorder. Archives Disease in Childhood. 1998; 79: 381-3
Kewley GD. Attention Deficit Hyperactivity Disorder is underdiagnosed and under treated in Britain. Br Med J 1998; 316: 1594-6
Levy F. Attention Deficit Hyperactivity Disorder. Br Med J 1997; 315: 894-5
Zametkin AJ, Ernst M. Problems in the management of Attention Deficit Hyperactivity Disorder. New Eng J Med 1999; 340: 40-46

Conclusion

ADHD is a common condition. The diagnosis should be suspected in children in whom hyperactivity, impulsiveness and inattention are interfering with normal social functioning. Advice from the child's school is helpful. The response to therapy, including medication is good and such children should be referred to the local child health services for assessment and management.