Rs. Tepper et al., HEIGHTENED AIRWAY RESPONSIVENESS IN NORMAL FEMALE-CHILDREN COMPARED WITH ADULTS, American journal of respiratory and critical care medicine, 149(3), 1994, pp. 678-681
Citations number
28
Categorie Soggetti
Emergency Medicine & Critical Care","Respiratory System
Studies have suggested that airway responsiveness declines with matura
tion; however, studies comparing infants, children, and adults are con
founded by differences in size as well as maturation. Therefore, to de
termine whether maturation has a significant affect on airway responsi
veness, we compared normal female children (n = 9; mean age = 13.6 yr)
and adults (n = 7; mean age = 42.4 yr) who were matched for body size
. Bronchial challenge tests were performed with increasing methacholin
e concentrations to a maximum of 30 mg/ml. At baseline, there were no
significant differences between the two groups in lung volumes (TGV, R
V, TLC) or flow-volume curves (FEV(1), average forced expiratory flow
rate between 25% and 75% of the vital capacity [FEF(25-75)], FVC). All
subjects but one adolescent completed the challenge (30 mg/ml). The c
hildren had a greater percentage decline from baseline in FEV(1) than
the adults (17 versus 7%, p < 0.03). The percentage decline in FEF(25-
75) was greater for the children than for the adults, but the differen
ce was not statistically significant (35 versus 20%, p < 0.10). Compar
ed with the children, the adults more often demonstrated a plateau in
their dose-response curves for FEV(1) (22 versus 86%) and for FEF(25-7
5) (33 versus 100%). We conclude that normal female children have a gr
eater airway responsiveness to inhaled methacholine than do adults, an
d that this difference is not related to baseline lung size, airway ca
liber or delivered methacholine dose.