[1] East Carolina Univ, Brody Sch Med, Div Pulm Crit Care & Sleep Med, 3E-149E Brody Med Sci Bldg,600 Moye Blvd, Greenville, NC 27834 USA
[2] Albany Med Coll, Div Pulm & Crit Care Med, Albany, NY 12208 USA
[3] Kings Coll Hosp London, London, England
[4] Univ Colorado, Div Environm & Occupat Hlth Sci, Natl Jewish Hlth, Denver, CO 80202 USA
[5] Univ Colorado, Div Pulm Sci & Crit Care Med, Denver, CO 80202 USA
[6] Univ Colorado, Dept Med, Sch Med, Denver, CO 80202 USA
[7] Univ Colorado, Colorado Sch Publ Hlth, Dept Environm Occupat Hlth, Denver, CO 80202 USA
[8] Royal Brompton Hosp, Interstitial Lung Dis Unit, London SW3 6NP, England
[9] Univ Cincinnati, Dept Med, Cincinnati, OH USA