Phenomenology of COPD: interpreting phenotypes with the ECLIPSE study.

The Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points (ECLIPSE) study was a large 3-year observational multicentre international study aimed at defining COPD phenotypes and identifying biomarkers and/or genetic parameters that help to predict disease progression. The study has contributed to a better understanding of COPD heterogeneity, with the characterization of clinically important subtypes/phenotypes of patients, such as the frequent exacerbators or patient with persistent systemic inflammation, who may have different prognosis or treatment requirements. Because of the big amount of information that is starting to be produced from metabolomic, proteomic and genomic approaches, one of the biggest challenges is the integration of data in a biological prospective such as clinical prognosis and response to medicinal products. In this article we highlight some of the progress in phenotyping the heterogeneity of the disease that have been made thanks to the analyses of this longitudinal study.