000480 - Impact of Food Form on Eliciting Dose Relative to Habitual Intake During Cow’s Milk Oral Food Challenge: A Real-World Analysis

Although regular intake of allergenic foods is known to influence clinical reactivity, the relationship between habitual intake amount and eliciting dose (ED) during oral food challenge (OFC), particularly in relation to food form, remains insufficiently understood in real-world clinical settings. We examined whether ED fold change differs between milk-containing steamed bread and milk.

We conducted a retrospective matched cohort study of children who underwent OFC for cow’s milk between 2021 and 2025 at the National Center for Child Health and Development, Japan. Participants were classified according to their habitual intake form (milk-containing steamed bread or milk) and matched 1:1 according to age, history of anaphylaxis to the challenge food, casein-specific IgE levels, and duration of habitual intake prior to OFC. EDs were compared between groups using parametric models. ED fold change was defined as the ratio of the eliciting dose during OFC to the amount of allergen habitually consumed prior to the challenge. This study used an opt-out consent process and was approved by the institutional ethics committee. (2023-250)

After matching, 221 participants were included in each group. The matching variables—age (median 9 vs 10 years), casein-specific IgE levels (19.1 vs 18.0 kUA/L), history of anaphylaxis (52.5% vs 60.6%), and duration of habitual intake (median 12 months)—were comparable between the two groups.

ED fold change tended to be higher in the steamed bread habitual intake group than in the milk habitual intake group. Specifically, the estimated dose at which 20% of participants developed symptoms (ED20) showed a fold change of 4.8 (95%Cl:3.5-7.1) in the steamed bread habitual intake group and 3.9 (95%Cl:3.0-5.1) in the milk habitual intake group. By contrast, 20% of participants in the steamed bread habitual intake group and 24% in the milk habitual intake group reacted at a challenge dose equivalent to five times their habitual intake amount

In this real-world matched analysis, ED fold change during OFC differed according to habitual food form. Habitual intake of milk in a processed form, such as milk-containing steamed bread, was associated with ED fold changes that were at least comparable to, and potentially more favorable than, those observed with direct milk intake when assessed relative to habitual consumption, highlighting relevance for dietary guidance and risk assessment in children with food allergy.