To evaluate strategies of early peanut consumption or avoidance for prevention of peanut allergy in patients at risk.
The participants were between 4 and 11 months of age at randomization. They suffered from severe eczema, egg allergy, or both.
A total of 640 patients were evaluated over a 60-month period. They were stratified according to their sensitivity to skin testing to peanut extract. Those with no measureable wheal were evaluated as not sensitized, those with wheal diameters 1 to 4 mm were considered sensitized, and participants with >4-mm wheal were excluded. Participants were randomized to receive an initial supervised feeding of peanut or to avoid peanut. Those tolerating an initial peanut feeding were instructed on incorporating peanut into the diet. Participants underwent peanut feeding tests at 5 years of age.
Of the 530 infants in the intent-to-treat population who initially had negative skin tests, the prevalence of peanut allergy at 60 months was 13.7% in the avoidance group and 1.9% in the consumption group. Of the 98 participates in the group who initially had positive tests, the prevalence of peanut allergy was 35% in the avoidance group and 10% in the consumption group at 60 months. There was no significant difference in the incidence of serious adverse effects. Increase in levels of peanut-specific immunoglobulin (Ig)G4 antibody occurred predominantly in the consumption group, and a greater percentage of participants in the avoidance group had elevated titers of peanut-specific IgE antibody. A larger wheal at skin prick test and a lower ratio of peanut specific IgG4:IgE were associated with peanut allergy. In the intent-to-treat group, the overall reduction rate of peanut allergy from 17.2% in the peanut avoidance group to 3.2% in the peanut consumption group relates to ∼80% relative risk reduction in developing peanut allergy and a 14% absolute risk reduction. This corresponds to a number needed to treat of 7.1. A total of 7 children reacted to peanut at baseline before randomization, and 9 children in the consumption group developed peanut allergy during the study.
The early introduction of peanuts in a high-risk group significantly decreased but did not nullify the chance of developing peanut allergy.
This is a landmark study indicating that early highly regulated consumption of peanut in a high-risk group of patients will bring a significant reduction in the occurrence of peanut allergy. It does not completely obviate the possibility of developing peanut allergy. It should also be noted that these data may not be directly extrapolated to patients other than those fitting the criteria of the study. Caveats and cautions include the following: whether eating peanut on a different schedule/amount than the study would have different results, whether discontinuation of eating peanut could result in loss of tolerance, and the concern that many peanut products may be choking hazards for infants and young children, requiring careful instructions about specific foods to use. These data are of great interest and should be evaluated in each individual practice setting to determine if the adoption of this protocol is possible.
- Copyright © 2015 by the American Academy of Pediatrics