A comparison of COPD patients with and without ACOS in the ECLIPSE study

There is growing interest in asthma–chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) [1, 2]. Yet, there is no consensus on the best definition of ACOS [1, 2] and, therefore, it is difficult to appropriately characterise these patients. Here, we compare the main clinical characteristics and outcomes of COPD patients with and without ACOS in the ECLIPSE cohort [3] according to six different definitions of ACOS. ECLIPSE offers an opportunity to examine ACOS in a large well-characterised COPD cohort followed over 3 years Editorial support (in the form of initial preparation of an outline only, based on input from the lead author) was provided by Julianna Solomons, and Natasha Thomas, of Fishawack Indicia Ltd, and was funded by GSK. The authors wish to acknowledge the following individuals for their and critical review during the development of this manuscript: Kaitlin Kelly-Reif (University of North Carolina, Chapel Hill, NC, USA), Greta Bushnell (University of North Carolina, Chapel Hill, NC, USA).