Am. J. Respir. Crit. Care Med., Vol 149, No. 4, Apr 1994, 899-904.
Host determinants of cellular and biochemical constituents of bronchoalveolar lavage fluids. Implications for design of epidemiologic studies
RB Everson, DM Schreinemachers, RB Devlin and HS Koren
Health Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711.
The effects of demographic characteristics, exercise, environmental
exposures, and other host factors on cellular and biochemical constituents
of human bronchoalveolar lavage (BAL) fluids were investigated by studying
more than 300 specimens obtained from normal volunteers and assayed in a
single center. The BAL data demonstrated associations with race, smoking,
exercise, skin-test reactions, and blood constituents, and weak or no
associations with age, sex, pulmonary function tests (PFT), or ambient
ozone exposure. The effect of exercise was relatively strong and more
clearly characterized than in previous studies. Smoking effects were
similar to those observed in other studies; our ability to study age and
ambient ozone effects was greatly limited because of the homogeneity of the
population under study. Blood constituents of the subjects also showed an
association with level of exercise. Analysis of intraindividual and
interindividual variability in BAL constituents results suggested that
matching, although desirable, is not essential for the maintenance of
adequate statistical power in BAL studies, so observational studies of the
effects from air pollution on BAL fluids in humans could be effectively
conducted using cross-sectional designs.
