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The use of psychostimulant medicines for the treatment of attention deficit-hyperactivity disorder (ADHD) is still a subject of controversy, put under the spotlight by the announcement that prescriptions of Ritalin (methylphenidate) and other ADHD medicines on the NHS have doubled in the past decade.

Media reports on the subject have often adopted a position of overdiagnosis and overprescribing but the evidence does not stack up. UK health watchdog the National Institute for Health and Care Excellence estimates that ADHD affects 5% of the childhood population, yet diagnostic prevalence fluctuates between 3% and 5% depending on which part of the UK you live, and prescribing rates differ significantly across England and Wales[1].

What is ADHD?

Reports in the media often focus on poor or neglectful parenting. Poor parenting does not cause ADHD, although it can exacerbate what epidemiological research has proven to be fundamentally a genetic condition[2],[3] whereby normal childhood behaviours such as hyperactivity, impulsivity, poor concentration and memory are of a disproportionate scale. Although first diagnosed in 1902, ADHD has been part of the human condition for millennia. Historically, ADHD neurology could have been a distinct survival advantage in a hunter gatherer culture. It became a “disorder” when, after years of evolution, we began to educate children in classrooms and socialise them in such a way that placed more emphasis on their intellectual development. However, ADHD does not correlate with low intelligence, but is associated with poor brain function in areas concerned with executive functioning such as problem solving, analysing and prolonged periods of concentration[4].

Diagnosis is now made more accurate through methods such as quantitative behaviour (QB) tests[5] — computerised cognitive function tests that are 80% accurate and inform paediatricians if behaviour is the result of a cognitive impairment or just poor socialisation and discipline.

The issue of comorbidity further confuses parents and teachers. Around 56% of children with ADHD will also have learning disorders such as dyslexia, dyscalculia (difficulty in making arithmetical calculations), dyspraxia (difficulty in planning and coordinating physical movement) and Asperger’s syndrome. Around 8% of children with ADHD will experience tics or Tourette’s and 41% will have comorbid conduct disorders. Developmental delay of up to three years is also common[6]. Of concern to overstretched health services is the disproportionate number of children with ADHD who experience anxiety, depression, suicidal ideation, addiction and eating disorders, all of which are symptomatic of low emotional resilience that is the result of both genetics and environmental stressors[7].

The first question we have to ask is why more children are being diagnosed with ADHD. The general consensus among clinicians is that it is a combination of genetic predisposition and environmental factors that interact to determine the presentation of the condition. There is some research, however, that suggests older parents are at greater risk of having children with neurodevelopmental disorders such as ADHD and that in vitro fertilisation children are also at increased risk. In modern western society, there is a trend towards having children later in life — on average over 30 years of age — which may account for why we are seeing more children presented for diagnosis[8],[9].

We are now moving away from the old notion of ADHD as a purely behavioural disorder and seeing it more in terms of developmental delay and impairment to the brains management system

The average age at diagnosis is approximately nine years[6]. For children starting school at five years of age, the experience of being disciplined for forgetting what they have been taught because it is assumed they haven’t been listening can become a source of anxiety. Distressed children do not have the self-awareness or the language to express this emotional distress, which further impacts on their cognitive functioning and can lead to tantrums and inappropriate behaviours. ADHD, however, is not an excuse for underachievement or poor behaviour. We do children no favours if they are encouraged to believe they are not accountable.

We are now moving away from the notion of ADHD as a purely behavioural disorder and seeing it more in terms of developmental delay and impairment to the brain’s management system.

There is a greater awareness of ADHD now but some educationalists working with the ADHD Foundation in the UK believe that many children on the milder end of the spectrum are experiencing greater levels of ‘learner anxiety’ because of pressures at school. This may explain why more parents are seeking support and answers — even if that means a diagnosis for a ‘disorder’ is an attempt to ensure their child is given additional support in school and medicines to help them concentrate.

There is also the issue of many children on the autistic spectrum — 40% of whom have a dual diagnosis of ADHD and autism spectrum disorder — who often are given ADHD medicines[9],[10].

Overmedication?

The biological argument encourages drug treatment as a way of addressing ADHD, distinct from the psychosocial position that recommends psycho-educative and cognitive behavioural therapy-type interventions. The reality, however, is that there is a place for both interventions. Children on the milder end of the spectrum will benefit from learning skills and strategies to self-manage their condition and by taking a ‘strength-based approach’ they can learn to live successfully with the challenges of ADHD. For those children with more severe ADHD, medication is a valuable tool and is often necessary to enable the child to cope with the pressures of school and examination-focused learning. Pervasive anxiety leading to increased levels of stress hormones can impact on how the child’s brain develops both structurally and functionally, increasing the risk of long-term mental health problems.

Pharmaceutical companies that produce medicines to treat ADHD state clearly that they should not be used in isolation but as an adjunct to psycho-educative and behavioural support. The problem is that, in most parts of the UK, medication is not only the first-line of treatment but the only line of treatment[1]. Paediatricians are increasingly criticised in the media for overmedicating but they can only offer what the NHS commissioners in their area will fund — and the reality is that overstretched children’s mental health services do not offer an alternative to medication or such psychosocial interventions as an adjunct to pharmacology.

Prescribing such medicines for children, however, is not an exact science. Children respond differently to different types of ADHD medicines and some experience unpleasant side effects. Regular medication reviews are necessary as the child grows and develops physically and psychologically, usually requiring six-monthly medication reviews with a paediatrician.

There is also a concern about a rise in girls being prescribed ADHD medicines. The ratio of boys to girls who were diagnosed with ADHD was 4:1 a decade ago. There needs to be a better understanding of how ADHD presents differently in girls since they are more likely to present as predominantly inattentive rather than hyperactive, resulting in them being diagnosed later in early adolescence when they often have comorbid mental health vulnerabilities such as anxiety, depression or eating disorders[11]. The imperative for diagnosis usually derives from the fact that the parent or school refer on the basis of poor behaviour rather than cognitive impairment, but the behaviour is a symptom not the core condition.

Improving outcomes

If addressed before the age of 14 years, childhood mental health problems are likely to end in a full recovery and psychological well-being. Early diagnosis and intervention is crucial in improving outcomes for these vulnerable children. Equally we should not incline to pathologising children, but instead differentiate for their needs, seeing them as different rather than disordered. Medication is a successful tool for many children, but it is not a cure and it does not teach them how to live successfully with the condition and learn how to take a strength based approach to achieving their potential.

Pharmacists would benefit from having a better understanding of how psychostimulant medicines work and their common side effects so they can advise parents about what to expect and when to seek a further consultation with a paediatrician to ensure the right type of medicine and the right dosage is prescribed. Care should also be taken when offering generic medicines and advice should be given to parents about reporting any potential changes in side effects or efficacy.