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by infrequent symptoms , can still be at risk of severe and life-threatening exacerbations . 10 Incorporating ICS therapy into the regimens of these patients can reduce this risk .
For patients with more frequent symptoms , the recommended strategy is regular use of moderate doses of ICS . The dose of ICS should be stepped up in response to persistent symptoms . 2
In addition to symptoms , a history of asthma exacerbations in the past year and markers of eosinophilic inflammation — as defined by blood eosinophils ≥0.3 cells x 109 / L or FeNO ≥25 parts per billion — add further prognostic information about the risk of future asthma attacks . They can also be used to aid decision-making by prompting the clinician to escalate ICS doses in response to the presence of these traits . 11
It is equally important for the clinician to consider the adverse effects of excessive ICS therapy and to de-escalate to the lowest effective dose when able . The shape of the ICS dose – response curve is such that the majority of the clinical effect is generally achieved in the low- to medium-dose range . Dose escalations above this add relatively little benefit . 12 Patients who are prescribed medium to high doses of ICS are at risk of clinically significant
13 , 14 systemic side effects of corticosteroids .
The addition of a LABA has been demonstrated to reduce exacerbations and is recommended as an add-on option if symptoms or exacerbations persist despite moderate-dose ICS . 15 The use of a LABA alone has been linked with a higher risk of asthma-related deaths and should
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not be used to treat asthma without an ICS . 16
The use of ICS – formoterol combinations as both maintenance and reliever therapy reduces the risk of exacerbations and provides similar symptom control compared with higher fixed-dose ICS / LABA combinations with SABA as a reliever . 17 As a result , ICS – formoterol combinations are the preferred strategy in recently updated guidance .
The addition of a long-acting muscarinic antagonist , such as tiotropium , improves exacerbation rates , lung function and symptom control when added to ICS / LABA combinations and can be considered
Biologic therapy has revolutionised the management of severe asthma in recent years .
if asthma is refractory to ICS / LABA therapy . 18 There are now PBS listings for triple inhaler therapy for severe asthma .
Challenges The contrasting approaches to inhaler management in asthma and COPD often create a management dilemma when a patient does not clearly have either condition or exhibits traits of both .
In contrast to asthma , the cornerstone of COPD management is long-acting bronchodilator therapy , and ICS therapy is only recommended in more severe forms of COPD that are characterised by frequent exacerbations . In these settings , if asthma
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traits are present , it is prudent to incorporate an ICS into the regimen , considering the demonstrated mortality benefit of ICS therapy in asthma . Traits that may prompt consideration of the addition of an ICS in a patient with predominately smoking-related COPD include variable airflow obstruction or elevated blood eosinophils ( ≥0.3 cells x 10 9 / L ).
Patients who still experience frequent symptoms or exacerbations despite highdose ICS / LABA combinations should be considered for advanced add-on therapies under the guidance of specialist clinics .
Biologic therapy has revolutionised the management of severe asthma in recent years . These agents are targeted against specific aspects of the immune cascade that contribute to asthma , including omalizumab ( anti-IgE ), mepolizumab and benralizumab ( anti-IL5 / R ) and dupilumab ( anti-4Rα ). These agents are administered as regular subcutaneous injections and are generally well tolerated . They are markedly effective at reducing asthma exacerbations , reducing oral steroid burdens and improving symptom control . 20-22
For patients who are either not candidates for biologic therapy or refractory to these treatments , regular macrolide antibiotics are often used because of their demonstrated effectiveness at reducing asthma exacerbations . 23
Patients with severe asthma can benefit from specialist respiratory clinics , and referral should be considered in the event of persistent symptoms or exacerbations despite high-dose ICS and bronchodilator therapy . 2
These specialist services can facilitate
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advanced add-on therapy , can provide diagnostic clarification in atypical cases and are typically resourced to provide systematic and multidisciplinary care . 19
Conclusion
GPs have a pivotal role to play in the appropriate diagnosis and management of asthma . Ensuring affected patients are suitably identified and treated can significantly reduce disease burden , improve quality of life and reduce deaths from this highly treatable chronic condition .
References on request from kate . kelso @ adg . com . au
Online resources
• Global Initiative for Asthma : ginasthma . org — International guidelines for all clinicians involved in asthma care , with up-to-date evidence and expert consensus
• National Asthma Council : nationalasthma . org . au — Information and resources for both patients and health professionals , including how-to videos and examples of written action plans
• Severe Asthma Toolkit : toolkit . severeasthma . org . au — A useful online resource with education and multimedia for clinicians and a focus on severe asthma
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