Abstract
Background
Allergic sensitization and respiratory infections commonly occur in childhood. Interplay between them in asthma development is known as the ‘two-hit’ hypothesis. There has been no previous investigation of this hypothesis on adult lung function.
Objective
In a birth cohort at high risk for allergic diseases, we investigated interactions between these two factors and lung function outcomes into adulthood.
Methods
Allergic sensitization was assessed at age 24 months by skin prick testing to aero and food allergens. Respiratory infection was defined as cough, rattle or wheeze measured by frequent questionnaires up to age 24 months. Regression models were utilized to identify interactions between these exposures and associations with lung function at ages 12, 18 and 25 years.
Results
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| Association between respiratory infection (increasing number of months) and allergic sensitization with change in lung function z-scores (post-bronchodilator)—sensitization status at 2 years. |









