The prevalence of peanut allergy in children has more than quadrupled over the past 15 years and can be a cause of life-threatening reactions in some cases. It has become the leading cause of anaphylaxis and death related to food allergy in the United States. Because of the high number of children impacted, researchers are working to find better ways to care for these young patients.
“Peanut allergy significantly affects quality of life for these children and their families because of dietary and social restrictions, but the main stress factor stems from a fear of accidental peanut ingestion,” says Carol Smith, MD, of Birmingham Allergy & Asthma Specialists. “Currently, we treat our patients with peanut allergy through strict avoidance of peanuts, education, and rescue medications, but these methods can be challenging for families because peanut is hidden in so many food products.”
Smith says the best scenario would be to find a way to avoid developing peanut allergy in the first place. “The American Academy of Pediatrics initially recommended that high-risk infants avoid having peanut in their diets until age three,” she says. “But as the prevalence of peanut allergy continues to rise, there appears to be insufficient evidence to support early avoidance. In fact, subsequent studies have suggested that earlier introduction was associated with a decrease in the development of food allergy.”
A new study published in the New England Journal of Medicine online is generating some excitement among allergists. In the Learning Early About Peanut (LEAP) study, findings suggest that the risk of developing peanut allergy can be dramatically reduced with early introduction (before 11 months) of peanut-based products.
“The LEAP study makes it clear that we can do something now to reverse the increasing prevalence of peanut allergy,” authors of the study say. “Because the results of this trial are so compelling and the problem of the increasing prevalence of peanut allergy is so alarming, new guidelines should be forthcoming soon.”
The study included 640 infants between four and 11 months of age who were considered at high risk for developing peanut allergy because of severe eczema, egg allergy or both. Participants in the study were assigned randomly to peanut consumption or peanut avoidance after undergoing a baseline skin prick peanut test. Those assigned to consumption were also given a baseline food challenge.
The children who tested negative on the initial skin-prick test underwent primary prevention and were given two grams of peanut protein in a single dose. Those who tested positive on the initial skin-prick test underwent secondary prevention and were given incremental doses up to a total of 3.9 grams.
Anyone who had a reaction to the food challenge was moved into the avoidance group. Those who passed the food challenge were moved into the consumption group and fed at least six grams of peanut protein per week, distributed in three or more meals, until they reached age 60 months.
According to study investigators, “This intervention was safe, tolerated, and highly efficacious. In the intention-to-treat analysis, peanut consumption was associated with an 86-percent reduction in peanut allergy at 60 months of age among participants who had had negative results on a peanut-based skin-prick test at study entry and with a 70-percent reduction among those who had had positive skin-prick test results at study entry.”
Smith is encouraged by the results of the study but is cautious about the call for an immediate change in guidelines. “The good news is the results show that children who are given peanut early have a significantly reduced risk for developing the allergy,” she says,” but what do we do with this information? Should the guidelines be changed? Should we recommend introducing peanuts to all infants before 11 months of age? It’s not clear yet.”
The study investigators acknowledge that there still are unanswered questions, such as how much peanut protein should children consume and how frequently, and how long children will remain protected from developing the allergy, especially if they stop consuming peanuts. These and many other issues must be evaluated further.
In the meantime, Smith suggests that high-risk infants between four and eight months of age undergo skin-prick testing for peanut. If the test results are negative, consider early introduction of peanut products in a diet that includes two grams of peanut protein three times a week for at least three years.
Smith points out that any allergy practice guidelines will be developed by the American Academy of Allergy, Asthma & Immunology, but a certified allergist could go ahead and try the treatment described in the LEAP study. “Over the past 20 years, parents didn’t feed peanuts to their allergic children. Avoidance was thought to be the safest course,” she says. “LEAP has given us good information that we can continue to evaluate. I hope the remaining questions can be answered soon so we can begin to reduce the prevalence of peanut allergy in these patients and offer treatment that will improve their lives.
