Abstract
Presented at the European Respiratory Society (ERS) Annual Congress Stockholm, Sweden. 7–11 September 1996 (Abstract).
The importance of several potential risk factors for development of childhood atopy, airway hyperresponsiveness and wheezing, remains uncertain. We have determined risk factors for these features of asthma in a birth cohort of New Zealand children. Responses to respiratory symptom questions and measurements of lung function and airway responsiveness to methacholine were obtained every 2-3 years in 1037 children followed throughout childhood and adolescence with 85% cohort retention at age 18. Relationships between parental and neonatal factors, the development of atopy (positive skin tests at age 13) and features of asthma were determined by comparison of proportions and logistic regression. Male sex was an independent predictor for atopy, airway hyperresponsiveness, hay fever and asthma. A positive family history, especially maternal, of asthma predicted childhood atopy, airway hyperresponsiveness, asthma and hayfever (p < 0.05 for most relationships). Maternal smoking in the last trimester was correlated (p = 0.049) with onset of childhood asthma by age 1. Birth in winter increased the risk of cat sensitization (p = 0.003). Among those with a parental history of asthma or hayfever, birth in autumn and winter also increased the risk of house dust mite sensitization (p = 0.040). The number of siblings, position in the family, socioeconomic status and birth weight were not consistently predictive of any characteristic of asthma. These data suggest possible areas for interventions to reduce childhood asthma