Predictors of Food Sensitization in Children and Adults across Europe

Background: The geographical variation and temporal increase in the prevalence of food sensitization (FS) suggest environmental influences. Objective: To investigate how environment, infant diet, and demographic characteristics, are associated with FS in children and adults, focusing on early-life exposures. Methods: Data on childhood and adult environmental exposures (including, among others, sibship size, day care, pets, farm environment, and smoking), infant diet (including breast-feeding and timing of introduction to infant formula and solids), and demographic characteristics were collected from 2196 school-age children and 2185 adults completing an extensive questionnaire and blood sampling in the cross-sectional pan-European EuroPrevall project. Multivariable logistic regression was applied to determine associations between the predictor variables and sensitization to foods commonly implicated in food allergy (specific IgE ≥0.35 kU _A/L). Secondary outcomes were inhalant sensitization and primary (non–cross-reactive) FS. Results: Dog ownership in early childhood was inversely associated with childhood FS (odds ratio, 0.65; 95% CI, 0.48-0.90), as was higher gestational age at delivery (odds ratio, 0.93 [95% CI, 0.87-0.99] per week increase in age). Lower age and male sex were associated with a higher prevalence of adult FS (odds ratio, 0.97 [95% CI, 0.96-0.98] per year increase in age, and 1.39 [95% CI, 1.12-1.71] for male sex). No statistically significant associations were found between other evaluated environmental determinants and childhood or adult FS, nor between infant diet and childhood FS, although early introduction of solids did show a trend toward prevention of FS. Conclusions: Dog ownership seems to protect against childhood FS, but independent effects of other currently conceived environmental and infant dietary determinants on FS in childhood or adulthood could not be confirmed.