Use of partially hydrolysed formula in infancy and incidence of eczema, respiratory symptoms or food allergies in toddlers from the ELFE cohort

Background and objectives Partially hydrolyzed formulas (pHF) are recommended in non-breastfed infants with familial history of allergy to prevent allergy development. However, recent meta-analysis does not provide strong support for their protective effect. The present work assesses the links between 2-month infant formula use and the incidence of eczema, respiratory symptoms, or food allergies (FA) up to 2 years of age. Methods The nationwide ELFE birth cohort is a population-based study from mainland France. Infant feeding (breast milk only, partially hydrolyzed formula with [pHF-HA] or without a hypoallergenic label [pHF-non-HA], and non-hydrolyzed formula [Nhf]) was reported at 2 months. Eczema, FA, and respiratory symptoms such as wheezing and asthma were reported at 2 months, 1 year, and 2 years. Infants with prior FA at 2 months were excluded from analyses. Results Among 11 720 infants, those who received only breast milk at 2 months were at lower risk of eczema at 1 year than those who received nHF (OR[95% CI] = 0.78[0.65-0.94] in non-at-risk infants; 0.86[0.75-0.98] in at-risk infants). The use of pHF-HA, compared with nHF, at 2 months was related to higher risk of wheezing at 1 year in at-risk infants (1.68[1.24-2.28]) and higher risk of FA at 2 years both in non-at-risk infants (3.78[1.52-9.41]) and in at-risk infants (2.31[1.36-3.94]). Conclusions In this nationwide study, pHF-HA use was not associated with a lower risk of any of the studied outcomes. Quite the reverse, it was associated with a higher risk of wheezing and FA. This should be confirmed in further studies.