Breast-feeding Duration and Infant Atopic Manifestations, by Maternal Allergic Status, in the First 2 Years of Life (KOALA Study)

Abstract

Snijders BEP, Thijs C, Dagnelie PC, et al. J Pediatr. 2007;151(4):347–351 PURPOSE OF THE STUDY. To investigate the potential effect of modification by maternal allergic status on the relationship between breastfeeding duration and infant atopic manifestations in the first 2 years of life. STUDY POPULATION. Data from 2705 infants of the KOALA Birth Cohort Study (Netherlands) were analyzed. METHODS. The data were collected by repeated questionnaires at 34 weeks’ gestation and 3, 7, 12, and 24 months postpartum. Total and specific immunoglobulin E measurements were taken on venous blood samples collected during home visits when the infants were 2 years of age. Relationships were analyzed by using logistic regression analysis. RESULTS. Longer duration of breastfeeding was associated with a lower risk for eczema in infants of mothers without allergy or asthma (Ptrend = .01) and slightly lower risk in those of mothers with allergy but no asthma (Ptrend = .14). There was no such association for asthmatic mothers (Ptrend = .87). Longer breastfeeding duration decreased the risk of recurrent wheeze independent of maternal allergy (Ptrend = .02) or asthma (Ptrend = .06) status. CONCLUSIONS. The findings show that the relationship between breastfeeding and infant eczema in the first 2 years of life is modified by maternal allergic status. The protective effect of breastfeeding on recurrent wheeze may be associated with protection against respiratory infections. REVIEWER COMMENTS. The role of diet in preventing and treating atopic disease has been and continues to be an active area of clinical research. Snijders et al found that a longer duration of breastfeeding was associated with a lower risk of eczema in infants of mothers without allergy or asthma. There was a slight effect in mothers with allergy but no asthma, yet no such relationship was observed for asthmatic mothers. It is interesting to note that no effect modification of maternal allergy/asthma on infant IgE or allergen sensitization was observed. Finally, longer breastfeeding reduced the risk of recurrent wheezing independent of maternal allergic or asthma status, which the authors speculated may be the effect of reduced numbers of respiratory infections. Overall, these findings do support the role of breastfeeding in prevention of atopy, and additional studies are needed to better define the influence of maternal and infant diets during this time frame.