LUNG DEVELOPMENT AND EARLY ORIGINS OF CHILDHOOD RESPIRATORY ILLNESS

In the last two decades, 5 cohort studies have been initiated to exami ne the association of infant respiratory Function with genetic and env ironmental risk factors, as well as with subsequent lower respiratory illness in early childhood. While the current complexity of respirator y function tests in this age group precludes study samples with suffic ient power to examine more complex issues, information from these stud ies has provided an exciting adjunct to that available From the larger cohort studies. Premorbid alterations in airway function or lung deve lopment increase the risk of wheezing lower respiratory illnesses duri ng the preschool years and the risk of impaired airway function at 5-6 years of age. In addition, gender differences in airway function and the response to maternal smoking have been observed. Larger collaborat ive population-based studies are needed to explore the environmental, genetic and immunological mechanisms responsible, but will depend on t he development of; less invasive tests of airway function appropriate for use in healthy infants.