Combination of factors influence childhood food allergy risk

A combination of early allergic conditions, delayed allergen introduction, genetics, antibiotic exposure, demographic factors, and birth-related variables factor in the development of food allergy in children, according to a meta-analysis.

Researchers searched multiple online databases for cohort, case-control, and cross-sectional studies that examined risk factors for food allergy assessed via food challenge in children aged ≤6 years. A total of 190 studies involving 2.8 million participants across 40 countries met the eligibility criteria and were included in the meta-analysis.

Pooled data from studies using food challenge showed that the overall incidence of food allergy was 4.7 percent (moderate certainty).

Across 176 studies identifying 342 risk factors with varying certainty, the following factors showed the strongest and most certain association with the development of childhood food allergy: 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 (eg, peanut after age 12 months: OR, 2.55), early antibiotic exposure (first month: OR, 4.11; first year: OR, 1.39; in vitro: OR, 1.32), male sex (OR, 1.24), 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).

No associations were observed for factors such as low birth weight, post-term birth, maternal diet, and stress during pregnancy.