Allergenic food exposure at 3 months of age decreases food allergy at 36 months (PreventADALL)

Reference

Skjerven HO, Lie A, Vettukattil R, et al. Early food intervention and skin emollients to prevent food allergy in young children (PreventADALL): a factorial, multicentre, cluster-randomised trial. Lancet 2022;399(10344):2398-2411.

Synopsis

This study team recruited women who were receiving an 18-week antenatal ultrasound from 1 of 3 Norwegian hospitals. From this group, the investigators randomized healthy newborns, singletons or twins, with at least 35 weeks' gestational age (concealed allocation) to receive no intervention (n = 597), a skin intervention (n = 575), a food intervention (n = 642), or a combined intervention (n = 583). To reduce the possibility of contamination of interventions, the team randomized the newborns on the basis of 92 geographically distinct residential areas and 8 different 3-month time blocks (which means that infants born in the same 3-month period living in the same residential area were allocated to the same intervention group). Although the study participants knew the intervention assignment, the study personnel who monitored the participants were masked to the interventions. The skin intervention consisted of 5- to 10-minute baths with added petrolatum-based emulsified oil followed by topical cetirizine cream applied to the face. This intervention was to occur at least 4 days per week from age 2 weeks to 8 months, and the parents were discouraged from using soaps. The food allergy intervention consisted of sequentially adding allergenic foods (peanuts, cow’s milk, wheat, then eggs) to the infants’ regular diet at weekly intervals starting at age 3 months. In addition to parent-maintained diaries and parent-initiated contact in the event of problems, the study team evaluated the infants at 3, 6, 12, 24, and 36 months of age. The researchers had final data on 99.9% of the participants! Overall, 95% of the infants in each group were breastfed at 3 months. More than half the mothers had at least 4 years of college education compared with slightly less than half of their partners. Slightly more than one-third of the mothers and the fathers in each group reported atopy. The researchers classified the development of food allergy at 36 months (based on structured parental interviews, skin testing, and oral challenges in some cases) as probable, none, or unclear. Food allergy occurred in 1.1% of infants in the interventions using food (food intervention and combination intervention) compared with 2.6% in not using food (no intervention and skin intervention; number needed to treat = 63; 95% CI 37-196). There was no significant difference, however, between the infants who were exposed to skin interventions and those who were not exposed (2.1% vs 1.6%). The authors report that no safety concerns were identified during the study.