Prospective study of lung volumes in young asthmatic children

In a 9-y prospective study, the occurrence and duration of lung volume abnormalities in 21 young asthmatic children (median age at recruitment 4y, range 3–8 y) was determined. The median functional residual capacity (FRC) at recruitment was 135% of that predicted for height (range 79–187%) and 13 children were hyperinflated. The median FRC decreased significantly after 3 y of follow-up and by 9 y only one child remained hyperinflated. We conclude that persistent elevation of lung volume in young asthmatic children appears to be uncommon.