The Health and Economic Outcomes of Early Egg Introduction Strategies

Abstract

Researchers in this study modeled rates of egg allergy development and costs associated with early egg introduction (EEI) without screening compared with skin prick test (SPT) or serum-specific immunoglobulin E (sIgE) screening and delayed egg introduction.The computer simulation modeled high-risk infants with early-onset eczema in the United States, Canada, and Europe.The Markov modeling was based on published data including risks and benefits of EEI with cooked egg, eczema prevalence, 24% positive egg SPT results in infants with eczema, 6.6% annual egg tolerance development, and 5% annual inadvertent reactions to egg over a 20-year time frame. Infant cohorts were as follows: (1) EEI without screening, (2) SPT for egg sensitization in consultation with a board-certified allergist, (3) egg sIgE testing by a primary care provider, and (4) delayed egg introduction (>12 months of age) without screening. Costs considered included SPT, sIgE, allergy consultation, epinephrine autoinjectors, additional visits, and job-related opportunity costs.Egg allergy occurred in 2.5% of infants with EEI without screening versus 9.5%, 12%, and 21.4% with SPT screening, delayed introduction, and sIgE screening, respectively. Base model per patient incremental costs were $6865 US dollars for SPT by an allergist and $16 722 for sIgE by a primary care provider. Quality of life was similar across groups. Cooked EEI without screening remained the preferred strategy across multiple sensitivity analyses, including higher rates of allergy on first egg-exposure, lower rates of subsequent accidental egg reactions in children with egg allergy, lower rates of natural egg tolerance, higher rates of anaphylaxis fatality, exclusion of discount rates, and across both shorter and longer time horizons. A supplemental analysis of raw pasteurized EEI demonstrated that although this strategy was inferior to cooked EEI, raw pasteurized EEI was still preferred to screening testing (and also to delayed cooked egg introduction provided no more than 15.6% of infants reacted to initial raw pasteurized egg exposure).EEI without screening for high-risk infants resulted in the lowest percentage of infants developing egg allergy and the lowest cost. EEI after SPT screening and challenge for all positive SPT results resulted in fewer children with egg allergy and lower cost than delayed introduction.These simulations suggest that EEI without screening for egg sensitization is the preferred strategy for infants with no previous reactions to egg. SPT followed by a challenge if the SPT result is positive is associated with less egg allergy than delayed introduction, suggesting a role for limited SPT screening to facilitate early introduction in infants with eczema whose families are reluctant to introduce egg without screening. Although the modeling required making assumptions, extensive sensitivity analyses were performed and demonstrated robustness of EEI as the preferred strategy.