HOUSTON — The early introduction of peanuts significantly reduced the risk for the development of peanut allergy, according to LEAP data simultaneously published in the New England Journal of Medicine and presented in a keynote address today at the American Academy of Allergy, Asthma and Immunology Annual Meeting.
“At the end of the study, there was an 80% reduction in the prevalence of peanut allergy in consumers as compared to peanut avoiders. This is an extremely rigorous finding, even if we apply worst-case imputations to the statistics. It still remains significant,” George Du Toit, MB, BCh, study researcher of King’s College London and Guy’s and St. Thomas’ National Health Service Foundation Trust, London, told Healio.com/Allergy.
George Du Toit
Clinical practice guidelines have previously recommended against the inclusion of allergenic foods from the diets of high-risk infants and their mothers during pregnancy and lactation, according to data published in the United Kingdom in 1998 and the United States in 2000. Although these recommendations were withdrawn in 2008, studies have failed to prove that the exclusion of allergenic food prevented the development of an allergy, according to data published in the literature.
Du Toit and colleagues enrolled 640 infants aged at least 4 months but younger than 11 years with severe eczema, egg allergy or both, from December 2006 to May 2009.
The patients were separated into two study cohorts based on whether or not wheals of 1 mm to 4 mm were measured after a skin-prick test. Patients in each group (wheals, n = 98; no wheals, n = 542) were randomly assigned to peanut. Of those who tested negative, 530 were eligible for further evaluation. Assessments occurred at baseline (when patients were aged 4 months to 11 months) and at ages 12, 30, and 60 months.
At age 60 months, 13.7% of the avoidance group and 1.9% of the consumption group who initially tested negative on the skin-prick test developed an allergy, representing an 86.1% relative reduction in the prevalence of peanut allergy (P < .001), according to study data.
In addition, 35.3% of the avoidance group and 10.6% of the consumption group who initially tested positive on the skin-prick test developed a peanut allergy, representing a 70% relative reduction in the prevalence for peanut allergy (P = .004).
There were no significant between-group differences in the incidence of serious adverse events or hospitalization rates were observed, according to data.
Those who presented a larger wheal on the skin-prick test and a lower ratio of peanut-specific IgG4:IgE were associated with a peanut allergy, according to data.
Follow-up data on LEAP, in the LEAP-On Study, is almost complete, according to Du Toit. In that study, researchers have asked patients to avoid peanut for 1 year. The researchers will compare the rates 1 year later to investigate the potential benefits, he said. This will assess if the benefits through early peanut consumption with respect to a reduction in peanut allergy are sustained, regardless of ongoing peanut consumption.
Over the past 10 years, the prevalence of peanut allergy among children in Western countries has more than doubled from 1.4% to 3%; and also is now apparent in Africa and Asia, according to the literature.
“These [study] data should now be considered at the public health level,” Du Toit said. “National and indeed International Organisiations (such as NIAID, AAAI, ACACI, AAP, EAAACI, WAO) provide guidance with respect to weaning and allergy preventions are currently considering the results of the LEAP Study, and will issue consensus statements.” – by Samantha Costa and Ryan McDonald
Lack G, et al. Keynote 4701. Presented at: American Academy of Allergy, Asthma and Immunology Annual Meeting; Feb. 20-24, 2015; Houston.
Du Toit G, et al. N Eng J Med. 2015;doi:10.1056/NEJMoa1414850.
Gruchalla RS, et al. N Eng J Med. 2015;doi:10.1056/NEJMe1500186.
Disclosure: Du Toit reports no relevant financial disclosures. The LEAP study was funded by the National Institute of Allergy and Infectious Diseases, and the Food Allergy Research and Education. Please see the full study for a list of all other authors’ relevant financial disclosures.