© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com British Medical Bulletin, 2021, 137:82–97 doi: 10.1093/bmb/ldaa043 Advance Access Publication Date: 10 March 2021 Respiratory Medicine The different phenotypes of COPD Ahmed Yousuf, Hamish McAuley , Omer Elneima, and Christopher E Brightling * NIHR Leicester Biomedical Research Centre, Institute for Lung Health, Department of Respiratory Sciences, University of Leicester, University Road, Leicester, United Kingdom *Correspondence address. Institute for Lung Health, University Hospitals of Leicester, Groby road, Leicester, LE3 9QP, UK; E-mail: ceb17@le.ac.uk Received 15 June 2020; Revised 11 November 2020; Accepted 23 November 2020 Abstract Background: Chronic obstructive pulmonary disease (COPD) is associated with significant morbidity and mortality. To improve the health status and reduce symptom burden, it is important to identify a group of patients with similar characteristics and prognosis, called clinical phenotypes. Herein we shall review the different phenotypes of COPD. Sources of data: Keywords (COPD, phenotype, acute exacerbation) search was conducted in PubMed, Google Scholar. Areas of agreement: Those with raised blood eosinophil counts respond better to steroid therapy at stable state and exacerbation. Areas of controversy: There is no universally accepted blood eosinophil cut-off value that will indicate favourable response to corticosteroids and potentially for future biologic therapy. Growing points: There is an urgent need for further therapeutic options for COPD patients with non-eosinophilic inflammation. Areas timely for developing research: Well-designed COPD trials with iden- tification of phenotypes for more personalization of the treatment of COPD. Key words: COPD, phenotype, eosinophils, acute exacerbation, CRP, PCT Downloaded from https://academic.oup.com/bmb/article/137/1/82/6165964 by guest on 22 July 2022