A Third Year of Breastfeeding and Atopic Dermatitis Development: Data from a General Population Cohort of Full-Term Newborns

Background: breastfeeding may have some protective effect on atopic dermatitis (AD) development in children, but existing evidence is unclear. Studies on breastfeeding duration effect were inconclusive and data is limited to longitudinal data and population cohort recruitment in healthy full-term newborns. Objective: To evaluate an effect of prolonged breastfeeding on AD development in early childhood.

Methods: 393 mothers and their healthy full-term newborns were enrolled into general population-based prospective three-year cohort study. Breastfeeding duration and AD diagnostic criteria were evaluated in children at the age of 1, 2 and 3 years. Logistic regression model was used to evaluate association between AD in children and breastfeeding duration.

Results: Breastfeeding duration in the first two years of life had no influence on AD development. Breastfeeding during the third year of life was associated with a higher incidence of AD. There was no reverse causation found. Adjustment for maternal allergy history, maternal sensitisation, maternal age, parity, mode of delivery, maternal exposure to smoke during pregnancy and sex of a newborn did not influence analysis outcomes.

Conclusion: There is some evidence that prolonged breastfeeding, up to 25-36 months of life, is associated with a higher risk of AD in healthy full-term newborns regardless of maternal sensitisation and/or maternal allergy history. These results provide a reason to further research of prolonged breastfeeding influence on the risk of AD and other allergic diseases development.