Peanut Exposure in Children: We Should Look Before we LEAP
by Lora Stewart, MD
As you may know, a recent medical publication will likely change our approach to food allergies in our youngest patients. The LEAP (Learning Early About Peanut Allergy) study was published in the New England Journal of Medicine, one of the premiere journals in the medical community. The study suggests that we can prevent peanut allergy by feeding young patients peanuts regularly. This study will likely go down as key research in the world of food allergy science, but it is important to understand what this study really means and what it does not mean.
This study included 640 young children with severe eczema, egg allergy or both severe eczema and egg allergy. The children were very young – four to 11 months of age. All were skin tested to peanut before the study. A large number had a negative skin test to peanut and a small number had a small positive result to peanut. Then each patient was either placed in a group told to intentionally avoid all peanuts or in a group told to regularly eat peanuts. After five years, the researchers looked at how many kids were allergic to peanuts. It is important to note, that if a child had a significant skin test to peanut prior to the study or did not have severe eczema or an egg allergy, they could not be in the study. This is something to consider when determining if the results are applicable to other children.
After five years, the researchers found that in the group that had negative skin testing to peanut at the beginning, almost 14 percent of those kids who intentionally avoided peanuts were now allergic versus only 2 percent of the children who regularly ate peanuts. And for the group of kids with a small positive to peanut skin testing at the start of the study, 35 percent of the avoidance group were now allergic compared to only 11 percent of the peanut-eating group.
This suggests that eating peanuts starting at a young age may decrease the risk of being peanut allergic at age five. However, we need to keep in mind that this study had a specific population that either had severe eczema rash or already had an egg allergy. They also only looked at patients without a history of previous peanut reaction and very small positive peanut skin test results.
Nonetheless, the idea of exposure rather than avoidance in an “at risk” population is pivotal information that will likely change our approach to food allergy as we move forward.
References: Du Toit, G et al. Randomized Trial of Peanut Consumption in Infants at Risk for Peanut Allergy. N Engl J Med 2015; 72:803-813.