A recent retrospective cohort study conducted in Changsha, China, sheds light on the potential impact of environmental influences and antibiotic use on childhood food allergy. Led by researchers investigating the role of outdoor air pollution (OAP), indoor environmental factors (IEFs), and antibiotic use (AU) across critical developmental windows, the study provides valuable insights into the complex relationship between these factors and the prevalence of childhood doctor-diagnosed food allergy (DFA).
The study, involving 8689 preschoolers, aimed to explore the association between exposure to OAP and IEFs during various developmental periods—pre-pregnancy, prenatal, early postnatal, and current—and the occurrence of childhood DFA. Data on health outcomes, antibiotic use, and home environments were collected through questionnaires, while temperature and air pollutants data were obtained from monitoring stations in Changsha.
The findings revealed significant associations between childhood DFA and exposure to postnatal OAP, particularly to pollutants such as PM10, CO, O3, and SO2. Notably, exposure to these pollutants during the first year of life was linked to an increased risk of DFA, highlighting the importance of early-life environmental exposures in shaping allergic outcomes.
Furthermore, exposure to IEFs, including renovation-related indoor air pollution (IAP) and dampness-related indoor allergens, was found to significantly increase the risk of childhood DFA across all time windows. Smoke-related IAP, such as environmental tobacco smoke and parental smoking, during pregnancy and early childhood also showed associations with DFA.
Additionally, exposure to pet-related indoor allergens, such as cats, during infancy, as well as plant-related allergens, particularly nonflowering plants, during previous years, was associated with childhood DFA. Interestingly, different types of food allergies, including egg, milk, and other food allergies, were influenced by specific environmental exposures.
Moreover, the study highlighted the role of antibiotic use in increasing the risk of childhood DFA, with both lifetime and early-life AU showing associations with various types of food allergies.
Overall, the study underscores the importance of considering environmental factors and antibiotic use in understanding the development of childhood food allergy. These findings support the “fetal origin of childhood FA” hypothesis and emphasize the need for further research and public health interventions aimed at mitigating environmental exposures and promoting prudent antibiotic use to reduce the burden of childhood food allergy.
