Exercise-induced interstitial pulmonary edema at sea-level in young and old healthy humans

We asked whether aged adults are more susceptible to exercise-induced pulmonary edema relative to younger individuals. Lung diffusing capacity for carbon monoxide (DLCO), alveolar-capillary membrane conductance (D-m) and pulmonary-capillary blood volume (V-c) were measured before and after exhaustive discontinuous incremental exercise in 10 young (YNG; 27 +/- 3 years) and 10 old (OLD; 69 +/- 5 years) males. In YNG subjects, D-m increased (11 +/- 7%, P=0.031), V-c decreased (-10 +/- 9%, P=0.01) and DLCO was unchanged (30.5 +/- 4.1 vs. 29.7 +/- 2.9 mL/min/mm Hg, P=0.44) pre- to post-exercise. In OLD subjects, DLCO and D. increased (11 +/- 14%, P=0.042; 16 +/- 14%, P=0.025) but V-c was unchanged (58 +/- 23 vs. 56 +/- 23 mL, P=0.570) pre- to post-exercise. Group-mean D-m/V-c was greater after vs. before exercise in the YNG and OLD subjects. However, D-m/V-c was lower post-exercise in 2 of the 10 YNG (-7 +/- 4%) and 2 of the 10 OLD subjects (-10 +/- 5%). These data suggest that exercise decreases interstitial lung fluid in most YNG and OLD subjects, with a small number exhibiting evidence for exercise-induced pulmonary edema. (C) 2013 Elsevier B.V. All rights reserved.