Risk Factors for the Development of Food Allergy in Infants and Children: A Systematic Review and Meta-Analysis

Area of Science:

• Pediatric Allergy and Immunology
• Epidemiology of Allergic Diseases
• Genetics of Food Allergy

Background:

• The incidence and predictive risk factors for early-life food allergy remain incompletely understood.
• Accurate identification of risk factors is crucial for developing effective prevention strategies.

Purpose of the Study:

• To systematically estimate the incidence of food allergy in children up to age 6.
• To quantify the association between various factors and the development of food allergy.

Main Methods:

• Systematic literature search of MEDLINE and Embase databases.
• Meta-analysis of 190 studies involving 2.8 million participants.
• Inclusion of studies confirming food allergy via food challenge and assessing risk factors in children under 6 years.

Main Results:

• Overall food allergy incidence was estimated at 4.7% (moderate certainty).
• Strongest risk factors included prior allergic conditions (e.g., atopic dermatitis, allergic rhinitis, wheeze), delayed solid food introduction, infant antibiotic use, male sex, and family history.
• Other significant factors included increased skin water loss, filaggrin gene variations, parental migration, Black ethnicity, and cesarean delivery.

Conclusions:

• Childhood food allergy development is associated with a combination of major and minor risk factors.
• Key factors identified include early allergic conditions (atopic march), delayed allergen introduction, genetic predispositions, antibiotic exposure, demographic characteristics, and birth-related variables.
• These findings highlight the complex interplay of factors contributing to food allergy and inform potential preventative measures.