Prevalence and management of chronic breathlessness in COPD in a tertiary care center oleh H. Carette, M. Zysman, C. Morelot-Panzini, J. Perrin, E. Gomez, A. Guillaumot, P. R. Burgel, G. Deslee, P. Surpas, O. Le Rouzic, T. Perez, A. Chaouat, N. Roche, F. Chabot, on behalf of the Initiatives BPCO (bronchopneumopathie chronique obstructive) Scientific Committee and Investigators