Meta-analysis identifies risk factors for childhood food allergy

The development of early life food allergy may be predicted by a combination of major and minor factors, including early allergic conditions, delayed allergen introduction, genetics, and antibiotic exposure, among others, according to a meta-analysis.

Researchers searched multiple online databases for relevant cohort, case-control, and cross-sectional studies. They identified studies in which one or more factors for the development of IgE-mediated food allergy in children aged 6 years or younger were evaluated. Only studies that had food allergy confirmed through food challenge(s) were included.

A total of 190 studies involving 2.8 million participants across 40 countries were included in the meta-analysis. The overall food allergy incidence was 4.7 percent (moderate certainty).

Out of the 342 risk factors examined, the strongest and most certain factors associated with childhood food allergy were prior allergic conditions (atopic dermatitis within the first year of life: odds ratio [OR], 3.88; allergic rhinitis: OR, 3.39; wheeze: OR, 2.11), severity of atopic dermatitis (OR, 1.22), increased skin transepidermal water loss (OR, 3.36), filaggrin gene sequence variations (OR, 1.93), delayed solid food introduction (peanut after age 12 months: OR, 2.55), early life antibiotic exposure (first month: OR, 4.11; first year: OR, 1.39; in utero: OR, 1.32), male sex (OR, 1.24), being a firstborn child (OR, 1.13), family history of food allergy (mother: OR, 1.98; father: OR, 1.69; both parents: OR, 2.07; siblings: OR, 2.36), parental migration (OR, 3.28), self-identification as Black (vs White: OR, 3.93; vs non-Hispanic White: OR, 2.23), and caesarean delivery (OR, 1.16).

Factors such as low birth weight, post-term birth, maternal diet, and stress during pregnancy showed no association with childhood food allergy development.