A description of the population from which the groups or cohorts will be selected Smokers who have a screening spirometry for COPD, either in general medicine, at a pulmonologist or in the CHIC or Henri Mondor hospital respiratory function tests department.
After screening, an equal number of men and women COPD will be included (150 men and 150 women). 1500 smokers will be included to reach 300 smokers with COPD.
