Identifying high-risk infants

Identifying babies who are genetically predisposed to asthma before or shortly after birth means that parents can be given timely advice on factors that may be involved in the development of atopy or asthma.

A number of risk factors for the development of asthma in children have been identified.^{2,
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Factors that identify high-risk infants

Family history (both parents or one parent + one sibling) – Parental atopy and asthma are established factors that approximately double the risk of a child developing asthma.²⁴
Maternal smoking during pregnancy – Maternal smoking in pregnancy is a risk factor for all types of wheezing but not for asthma itself. Exposure to maternal smoking in utero has been associated with long-term deficits in lung function.²⁵

The presence of a family history is most useful in identifying at-risk neonates in routine clinical practice.²⁶ Other indices (eg cord blood IgE, development of positive skin tests to food allergens during infancy, IgE responses to respiratory tract infections) have proven useful in research settings but may be difficult to perform in routine clinical practice.

It should be remembered that asthma is now so common among Australian children that many new cases develop in children without a positive family history.

It is important to distinguish between the use of interventions for the primary prevention of asthma and their use in secondary prevention of symptoms in people with established asthma.