2 DIAGNOSIS
A small prospective observational study in 40 children suggested that serial measurements of FENO and/or sputum eosinophilia may guide step down of inhaled corticosteroids (ICS).844 Another small study of 40 children showed that a rising FENO predicted relapse after cessation of ICS .840 The number of children involved in these step-down and cessation studies is small and the results should be interpreted with some caution until replicated in larger datasets. A better understanding of the natural variability of biomarkers independent of asthma is required and studies are needed to establish whether subgroups of patients can be identified in which biomarker guided management is effective. Table 8 summarises the methodology, measurement characteristics and interpretation of some of the validated tools used to assess symptoms and other aspects of asthma. Clinical issues When assessing asthma control a general question, such as “how is your asthma today?”, is likely to yield a non-specific answer; “I am ok”. Using closed questions, such as “do you use your blue inhaler every day?”, is likely to yield more useful information. As in any chronic disease of childhood, it is good practice to monitor growth at least annually in children diagnosed with asthma.
2.6.2
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When assessing asthma control use closed questions.
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rowth (height and weight centile) should be monitored at least anually in children with G asthma.
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Practitioners should be aware that the best predictor of future exacerbations is current control.
MONITORING ASTHMA IN ADULTS In the majority of patients with asthma symptom-based monitoring is adequate. Patients achieving control of symptoms with treatment have a low risk for exacerbations.107 Patients with poor lung function and with a history of exacerbations in the previous year may be at greater risk of future exacerbations for a given level of symptoms. ;;
Closer monitoring of individuals with poor lung function and with a history of exacerbations in the previous year should be considered.
In two small studies in a hospital based population, one of which only included patients with severe and difficult asthma, a management strategy that controlled eosinophilic airway inflammation resulted in less exacerbations.84-86 A strategy which controlled airways responsiveness resulted in a much higher dosage of inhaled corticosteroids and slightly less exacerbations.108 More research is needed before these strategies can be recommended for widespread use. Table 8 summarises the methodology, measurement characteristics and interpretation of some of the validated tools used to assess symptoms and other aspects of asthma. Some measures provide information about future risk and potential corticosteroid responsiveness (ie sputum eosinophil count, airway responsiveness and FENO) rather than immediate clinical control. Risk reduction, eg minimising future adverse outcomes such as exacerbations is an important goal of asthma management. Some patients have an accelerated decline in lung function in terms of FEV1; risk factors and treatment strategies for these patients are poorly defined. Further research in this area is an important priority. ;;
When assessing asthma control in adults use specific questions, such as “how many days a week do you use your blue inhaler?”.
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