Abstract
Despite asthma and chronic obstructive pulmonary disease being widely regarded as heterogeneous diseases, a consensus for an accurate system of classification has not been agreed. Recent studies have suggested that the recognition of subphenotypes of airway disease based on the pattern of airway inflammation may be particularly useful in increasing our understanding of the disease. The use of non-invasive markers of airway inflammation has suggested the presence of four distinct phenotypes: eosinophilic, neutrophilic, mixed inflammatory and paucigranulocytic asthma. Recent studies suggest that these subgroups may differ in their etiology, immunopathology and response to treatment. Importantly, novel treatment approaches targeted at specific patterns of airway inflammation are emerging, making an appreciation of subphenotypes particularly relevant. New developments in phenotyping inflammation and other facets of airway disease mean that we are entering an era where careful phenotyping will lead to targeted therapy.
Highlights
Despite asthma and chronic obstructive pulmonary disease being widely regarded as heterogeneous diseases, a consensus for an accurate system of classification has not been agreed
We concentrate on airway inflammation as a distinct disease domain in asthma and chronic obstructive pulmonary disease (COPD) and highlight the clinicopathologic importance of defining phenotypes of disease based on airway inflammation
Stratification of the baseline eosinophil count into tertiles in this study revealed that postbronchodilator forced expiratory volume in 1 second (FEV1) and symptom scores improved progressively compared with placebo from the lowest to highest eosinophil tertile.[22]
Summary
Airways Disease: Phenotyping Heterogeneity Using Measures of Airway Inflammation. Despite asthma and chronic obstructive pulmonary disease being widely regarded as heterogeneous diseases, a consensus for an accurate system of classification has not been agreed. Neither is specific, and considerable overlap exists, with fixed airflow obstruction a feature in some patients with severe asthma and partial reversibility a frequent feature of COPD. Both diseases are composed of a variety of different domains, for example, airflow obstruction (fixed, reversible), AHR, atopy, and airway inflammation. Inflammation is often dissociated from the degree of airway responsiveness in asthma or degree of airflow obstruction in COPD, and a similar disparity may be observed with symptoms.[3,4] For these reasons, it is important to characterize patients using a composite of measures that describe an individual patient.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Allergy, asthma, and clinical immunology : official journal of the Canadian Society of Allergy and Clinical Immunology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
