[1] Texas Tech Univ, Div Hosp Med, Dept Internal Med, Hlth Sci Ctr, El Paso, TX 79905 USA
[2] Sierra Providence Healthcare & Hosp, Div Hosp Med, Dept Med, El Paso, TX 79902 USA
[3] Hannover Med Sch, Dept Resp Med, Hannover, Germany
[4] German Ctr Lung Res DZL, Hannover, Germany
[5] Univ Pittsburgh Med Ctr UPMC, Div Pulm & Crit Care Med, Pittsburgh, PA USA
[6] Cleveland Clin, Dept Pulm & Crit Care Med, Resp Inst, Cleveland, OH USA
[7] Texas Tech Univ Hlth Sci Ctr El Paso, Dept Med, Div Cardiovasc Dis, El Paso, TX USA
[8] Cedars Sinai Med Ctr, Div Pulm & Crit Care Med, Los Angeles, CA USA