The Mixed Phenotype of Asthma and COPD: the Overlap Syndrome

RATIONALE: In asthmatic subjects, smoking can lead to several changes in disease characterictics. in smokers of more than 20 pack-years, chronic obstructive pulmonary disease (COPD) can be associated with asthma, also called asthma-COPD overlap syndrome (ACOS). Increasing data support the concept that ACOS is a clinical entity. However, this should be further studied in order to better target therapy. AIM: The objective of this study is to evaluate the comparative features of ACOS METHODS: This will be a descriptive study comparing the features of the ACOS with the features of asthmatic subjects with an incomplete reversibility of airway obstruction (IRAO).The study will be done over 1 or 2 visits (within a week interval), according to subjects' availability. The visit will include completion of different questionnaires (asthma control asthma quality of life, medical history, exacerbations, etc.), a thoracic examination, allergy skin-prick tests, spirometry and bronchodilator response, lung volumes and compliance measurements, exhaled nitric oxide measurement, blood sampling and a sputum induction.