Abstract and Introduction
Purpose of review Asthma exacerbations occur unpredictably, are a cause of morbidity and mortality, and contribute significantly to increased healthcare costs. Inhaled corticosteroids reduce exacerbations and improve quality of life.
Recent findings The aetiopathology of asthma exacerbations is heterogeneous. Attempts to phenotype the heterogeneity of the pattern of airway inflammation by noninvasive monitoring of airway inflammation has identified a subgroup of patients with eosinophilic inflammation who are most likely to respond to steroid therapy. Strategies directed to normalize eosinophilic airway inflammation with corticosteroids have consistently led to a marked reduction in exacerbations. In contrast, their role in modulating the natural history of disease is less certain.
Summary In the near future, improvements in our understanding of the mechanisms of exacerbations may identify therapeutic targets. While we await these developments, inhaled corticosteroids remain the first choice anti-inflammatory therapy for asthma.
Asthma is characterized by symptoms of cough, breathlessness and wheeze punctuated by episodes of loss of disease control known as exacerbations, and is associated with airway hyperresponsiveness (AHR), variable airflow obstruction and inflammation. Inhaled corticosteroids (ICSs) form the cornerstone of asthma therapy and are of central importance in securing asthma control in patients with persistent disease. International guidelines advocate the titration of ICSs based primarily upon disease severity and symptoms.[1–3]
Patients across all the spectra of disease severity experience exacerbations; these events pose a risk to patients and are a major contributor to morbidity and mortality. The annual frequency of severe exacerbations across mild, moderate and severe groups were 5, 13 and 54%, and near fatal events 4, 6 and 23%, respectively. There is increasing evidence that airway inflammation is closely associated with exacerbations in asthma. However the mechanisms that drive exacerbations are complex and their long-term sequelae are poorly understood.
In this review, we shall describe the definition of asthma exacerbations, their heterogeneity and pathogenesis, and the role of ICSs in modulating airway inflammation, and discuss the evidence to support targeted ICSs strategies using biomarkers to effectively reduce asthma exacerbations. Finally, we will address whether the reduction in asthma exacerbations with ICSs impacts upon disease progression.
Curr Opin Pulm Med. 2011;17(1):16-22. © 2011 Lippincott Williams & Wilkins
Cite this: Can Inhaled Corticosteroids Prevent Asthma Exacerbations? - Medscape - Jan 01, 2011.