2 Clinical need and practice
2.1 Asthma is a chronic condition that causes symptoms such as shortness of breath (dyspnoea), chest tightness, wheezing, sputum production and cough associated with variable airflow obstruction and airway hyper-responsiveness. There are approximately 5.2 million people with asthma in the UK, nearly 1 million of whom are children. Asthma is the most common chronic disease in children, with a prevalence of between 17% and 23%.
2.2 Diagnosing asthma in children requires excluding other causes of recurrent respiratory symptoms. Persistent respiratory symptoms between acute respiratory attacks are suggestive of asthma, and a personal or family history of atopic conditions such as eczema or hayfever are also linked to asthma. If it is possible to perform lung function tests, bronchodilator responsiveness, peak expiratory flow (PEF) variability and bronchial hyper-reactivity testing may be used to confirm the diagnosis. In addition, allergy testing may be helpful in seeking causal factors.
2.3 Asthma attacks vary in frequency and severity. Many children with asthma are symptom-free most of the time, with occasional episodes of shortness of breath. Some children frequently cough and wheeze and may have severe attacks during viral infections, after exercise, or after exposure to allergens or irritants, including cigarette smoke.
2.4 Although mortality as a result of asthma is rare (38 deaths in children younger than 14 years were reported in the UK in 2004), the condition can have a significant impact on quality of life. One study in Australia suggested that one in five children with asthma did not ride a bike, play at school or play with animals, and one in three did not participate in organised sports. Other effects of asthma can include school absence and night disturbances.
2.5 The aim of asthma management is to control the symptoms, prevent exacerbations and – in school-aged children – to achieve the best possible lung function. Pharmacological management includes drugs such as inhaled corticosteroids (ICSs), and short- and long-acting beta-2 agonists (SABAs/LABAs). The latter should be used only in combination with an ICS. A large proportion of children with asthma are managed in primary care, often within nurse-led clinics. Community pharmacists may also play a role in educating children and their carers. General practitioners are encouraged to perform annual reviews on all registered people with asthma as part of the new General Medical Services contract and the Quality and Outcomes Framework in England.
2.6 Current British guidelines from the British Thoracic Society (BTS) and Scottish Intercollegiate Guidelines Network (SIGN) for the management of asthma recommend a stepwise approach to treatment in both adults and children. Treatment is started at the step most appropriate to the initial severity of the asthma, with the aim of achieving early control of symptoms and optimising respiratory function. Control is maintained by stepping up treatment as necessary and stepping down when control is good.
2.7 Mild intermittent asthma (step 1) is treated with inhaled SABAs, as required. The introduction of regular preventer therapy with ICSs (step 2) should be considered when a child has had exacerbations of asthma in the previous 2 years, is using inhaled SABAs three times a week or more, is symptomatic three times a week or more, or is waking at night once a week because of asthma. In children who cannot take an ICS, a leukotriene receptor antagonist is recommended.
2.8 There is no precise ICS dose threshold for moving to step 3 (add-on therapy), in which a third drug is introduced. However, in children aged 5–12 years, the guidelines recommend a trial of add-on therapy before increasing the daily dose of ICS above the equivalent of 400 micrograms of beclometasone dipropionate. The first choice for add-on therapy in children older than 5 years is the addition of a LABA. In children aged 2–5 years, a leukotriene receptor antagonist should be considered. For children younger than 2 years, consideration should be given to referral to a respiratory paediatrician.
2.9 At step 4, further interventions may be considered if control remains inadequate. For children aged 5–12 years this may include increasing the daily dose of ICS to the equivalent of 800 micrograms of beclometasone dipropionate, or adding leukotriene receptor antagonists or theophyllines. For children younger than 5 years, step 4 is referral to a respiratory paediatrician (if not already from step 3). At step 5 (for children aged 5–12 years only), continuous or frequent courses of oral corticosteroids are introduced. Before proceeding to this step, referral to a respiratory paediatrician should be considered. The majority of children with asthma are treated at steps 1, 2 or 3, with approximately 10% treated at either step 4 or 5.
2.10 Two important components of asthma management are maintaining adherence to medication and optimising inhaler technique. Studies of adults have suggested that the recommended doses of medication may only be taken on 20% to 73% of days, with average adherence (measured by the ratio of doses taken to doses prescribed) ranging from 63% to 92%. Records from the General Practice Research Database found that, over a 10-year period, only 42% of people obtained a repeat prescription for ICSs within the expected timeframe of the preceding prescription. With regard to inhaler technique, the ability to use an inhaler correctly is important for ensuring the delivery of the desired dose of a drug to the correct part of the lungs. Studies have reported that physicians assess inhaler technique as 'good' in 5–86% of adults. In children, this may be an even greater problem, with repeated education needed to make sure adequate technique is maintained.
2.11 NICE guidance on asthma devices for children aged 5–15 years (NICE technology appraisal guidance 38) recommends that ICSs are delivered using a press-and-breathe pressurised metered-dose inhaler (pMDI) with an appropriate spacer device. However, if a healthcare professional believes a child will be unable to use a press-and-breathe inhaler, other devices should be considered. The guidance also recommends that the child's therapeutic need and their ability and willingness to use a particular inhaler should be taken into account when choosing an inhaler. Guidance for children younger than 5 years (NICE technology appraisal guidance 10) also recommends the use of a pMDI and spacer device, with a face mask if necessary. Again, the choice of a device should take into account the needs of the child and the likelihood of good compliance.
 The British Thoracic Society and Scottish Intercollegiate Guidelines Network (2003; updated 2005) British Guideline on the Management of Asthma: a national clinical guideline. SIGN Guideline No. 63. Edinburgh: Scottish Intercollegiate Guidelines Network.