Breastfeeding and the development of asthma and atopy during childhood: a birth cohort study

Abstract

Objective. Within the context of a population based-birth cohort, we investigated the association between breastfeeding and development of asthma and atopy in childhood. Methods. Children (n=1072) were followed from birth and reviewed at age one, three, five and eight years. Based on the onset and resolution of symptoms, we assigned children into the wheeze phenotypes (never, transient, intermittent, lateonset and persistent). Atopy was determined by skin testing and specific IgE measurement. According to the duration of breastfeeding, participants were assigned as not breastfed, breastfed ≤ four months and breastfed > four months. Results. In a multinomial regression model adjusted for gender, we found that breastfeeding > four months was protective of transient early wheeze (aOR: 0.61, 95% CI 0.41-0.90, p=0.01), with no significant association between breastfeeding and other wheeze phenotypes. In a multivariate model, we found a significant protective effect of breastfeeding >four months on doctor-diagnosed asthma by age eight (aOR 0.59, 95% CI 0.39-0.88, p=0.01). However, we observed a strong trend which failed to reach statistical significance for breastfeeding >four months to increase the risk of atopy at age one year (aOR 2.41, 95% CI 0.94-6.14, p=0.07). There was no significant association between breastfeeding and atopy at any other time point. Conclusion. Breastfeeding may prevent viral-infection induced wheezing illnesses in early childhood (transient early wheezing).

Keywords

• Breastfeeding
• Asthma
• Atopy
• Childhood