[1] Ludwig Boltzmann Inst Lung Hlth, Vienna, Austria
[2] Maastricht Univ, Maastricht, Netherlands
[3] Netherlands & Ludwig Boltzmann Inst Lung Hlth, Vienna, Austria
[4] Vienna Healthcare Grp, Dept Internal Med & Pulmonol, Clin Penzing, Vienna, Austria
[5] Sigmund Freud Univ, Fac Med, Vienna, Austria
[6] Univ Liege, Dept Pneumol, Liege, Belgium