Abstract
Bronchiectasis is a heterogeneous disease. This study aimed at identifying discrete groups of patients with different clinical and biological characteristics and long-term outcomes.
This was a secondary analysis of five European databases of prospectively enrolled adult outpatients with bronchiectasis. Principal component and cluster analyses were performed using demographics, comorbidities, and clinical, radiological, functional and microbiological variables collected during the stable state. Exacerbations, hospitalisations and mortality during a 3-year follow-up were recorded. Clusters were externally validated in an independent cohort of patients with bronchiectasis, also investigating inflammatory markers in sputum.
Among 1145 patients (median age 66 years; 40% male), four clusters were identified driven by the presence of chronic infection with Pseudomonas aeruginosa or other pathogens and daily sputum: “Pseudomonas” (16%), “Other chronic infection” (24%), “Daily sputum” (33%) and “Dry bronchiectasis” (27%). Patients in the four clusters showed significant differences in terms of quality of life, exacerbations, hospitalisations and mortality during follow-up. In the validation cohort, free neutrophil elastase activity, myeloperoxidase activity and interleukin-1β levels in sputum were significantly different among the clusters.
Identification of four clinical phenotypes in bronchiectasis could favour focused treatments in future interventional studies designed to alter the natural history of the disease.
Abstract
Daily sputum and chronic infection with Pseudomonas or other bacteria define clinical phenotypes in bronchiectasis http://ow.ly/W4H9m
Footnotes
For editorial comment see Eur Respir J 2016; 47: 1037–1039 [DOI: 10.1183/13993003.00163-2016].
This article has supplementary material available from erj.ersjournals.com
Support statement: This study was supported by the European Multicentre Bronchiectasis Audit and Research Collaboration (EMBARC; www.bronchiectasis.eu). EMBARC is a European Respiratory Society Clinical Research Collaboration and has received funding from the European Respiratory Society, Bayer HealthCare and Aradigm Corporation. J.D. Chalmers acknowledges fellowship support from the Medical Research Council and the Wellcome Trust. M.J. McDonnell acknowledges fellowship support from the European Respiratory Society/European Lung Foundation and Health Research Board, Ireland. M.I. Restrepo's time is partially protected by Award Number K23HL096054 from the National Heart, Lung and Blood Institute. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Heart, Lung and Blood Institute or the National Institutes of Health. The funding agencies had no role in the preparation, review or approval of the manuscript. The views expressed in this article are those of the authors and do not necessarily represent the views of the Department of Veterans Affairs.
Conflict of interest: Disclosures can be found alongside the online version of this article at erj.ersjournals.com
- Received October 5, 2015.
- Accepted December 8, 2015.
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