Lung function measurements in children - copsac

elated to asthma or simply identifies infants at risk for subsequent wheezing from an
atopic predisposition or pre-existing abnormal lung function.
First aim was to determine the differential effect within monozygotic twin (MZ) pairs
discordant for severe RSV bronchiolitis in infancy on the subsequent development of
asthma, pulmonary function and allergy. 37 MZ twin pairs discordant for RSV
hospitalization in infancy were compared at the mean age of 7.6 years for lung function
and bronchial responsiveness. We found no differences within MZ twin pairs with
respect to pulmonary function, fractional exhaled nitric oxide, asthma prevalence,
asthma medication use, or sensitization.
Secondary aim was to compare prospectively the baseline lung function and bronchial
responsiveness in infants who later develop RSV bronchiolitis with infants who do not
develop such severe infection. In a prospective birth cohort study of 411 infants of
asthmatic mothers 22 infants developed RSV bronchiolitis. Infants with and without
RSV bronchiolitis did not differ significantly in baseline lung function or bronchial
responsiveness.
Conclusion: We found no effect of severe RSV bronchiolitis on the development of
asthma and abnormal pulmonary function, nor did baseline lung function seem to
predict later development of RSV bronchiolitis. This ague against a specific effect of the
RSV bronchiolitis in the development of asthma and may suggest a genetic factor or an
undisclosed environmental predisposing to severe RSV bronchiolitis, maybe coinfection
rather than mechanical difference as the distinguishing feature for the
development of RSV bronchiolitis.
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