The Association of Prolonged Breastfeeding and Allergic Disease in Poor Urban Children

Abstract

Purpose of the Study. To determine the association between allergic disease in children and prolonged breastfeeding. Study Population. A random sample (n = 861) of 15% of households from 2 poor suburbs of Cape Town, South Africa. Methods. Parents completed a validated International Study on Asthma and Allergies in Childhood questionnaire on allergic diseases for children aged 6 to 14 years. Other questions included breastfeeding duration, maternal smoking, and parental allergy. Results were adjusted for possible confounders and possible clustering within the household. Results. Of the 861 children included in the study, allergic disease in general and hay fever in particular were significantly less frequent in those with prolonged (>6 months) breastfeeding. There was a significant linear inverse association between breastfeeding duration and allergic disease in children without allergic parents but not in children with an allergic predisposition. Conclusions. These results from a developing country suggest a protective effect of prolonged breastfeeding on the development of allergic disease, particularly hay fever, in children born to nonallergic parents. This protective effect was not found in children with an allergic predisposition. Reviewer Comments. The results of this study found a significant protective effect of prolonged breastfeeding on the prevalence of allergic disease, which was most pronounced for hay fever. An interesting observation in this study was the inverse association of breastfeeding duration and risk of allergic disease in children without an allergic predisposition. The history of allergy in either parent seemed to neutralize the protective effect of prolonged breastfeeding. This has not been observed in studies regarding the prevention effect of breastfeeding in Westernized countries, where protection was stronger when the family risk was higher. This study suggests that although breastfeeding seems to be protective in the development of allergies, family history and genetics may provide an overriding factor, at least in this study population.