Changes in Food-Specific IgE Over Time in the National Health and Nutrition Examination Survey (NHANES)

BACKGROUND: Food allergy prevalence appears to have recently risen, with larger increases among non-Hispanic blacks. However, it is unclear whether these trends represent shifts in recognition of food allergy or in sensitization. OBJECTIVE: The objective of this study was to determine whether sensitization to common food allergens increased in US children from 1988-1994 to 2005-2006 and whether these trends differed by race and/or ethnicity. METHODS: Food-specific immunoglobulin E (IgE; to peanut, milk, egg, and shrimp) was measured by ImmunoCAP in stored sera from subjects aged 6-19 in the National Health and Nutrition Examination Survey (NHANES) III (1988-1994) and was compared with NHANES 2005-2006. Sensitization to foods was defined as overall (IgE >= 0.35 kU/L), moderate level (IgE >= 2 kU/L), and high level (IgE >= commonly used 95% predictive values). Sensitization to individual and combined foods was compared between surveys, with analyses further stratified by race and/or ethnicity. RESULTS: A total of 7896 subjects (NHANES III: n [4995, NHANES 2005-2006: n[2901) were included. In NHANES III, the prevalence of food sensitization was 24.3% (95% confidence interval [CI]: 22.1-26.5) compared with 21.6% (95% CI: 19.523.7) in NHANES 2005-2006. There were no significant changes in the prevalence of any level of milk, egg, or peanut sensitization, but shrimp sensitization at all levels decreased markedly; overall sensitization NHANES III: 11.2% (95% CI: 10.0-12.5) versus NHANES 2005-2006: 6.1% (95% CI: 4.5-7.7). There was a trend toward the increased prevalence of moderate-and high-level sensitization to the combination of milk, egg, and peanut among non-Hispanic blacks but not other groups. CONCLUSIONS: In contrast to our expectations, sensitization to common food allergens did not increase between the late 1980s/early 1990s and the mid-2000s among US 6-19 year olds, and in fact decreased to shrimp. (C) 2016 American Academy of Allergy, Asthma & Immunology