ASSOCIATION BETWEEN PACIFIER CLEANING METHODS AND CHILD TOTAL IGE.

Introduction Microbial-related exposures in early life stimulate immune development and may protect against allergic disease manifestations later in life. Parental pacifier sucking in early life may offer protection through the transfer of beneficial oral microbes from parent to offspring. Methods Using maternal-child pairs from the Microbes, Allergy, Asthma and Pets cohort(N=141), we investigated whether pacifier cleaning methods reported at 6-months of age were associated with differences in serum total IgE over the first 18 months of life(cord, 6-months, and 18-months). Linear mixed effect models were used to model log-transformed total IgE trajectories. Results Of 128 mothers completing an interview at 6 months, 74(58%) reported current child pacifier use. Of these 74, 30(41%) reported pacifier cleaning by sterilization, 53(72%) reported handwashing the pacifier, and 9(12%) reported parental pacifier sucking. Pacifier sterilization or handwashing were not associated with serum total IgE trajectory. A significant time interaction was detected for pacifier sucking(p=0.079), indicating that the trajectory shape differed between children of pacifier-sucking versus non-pacifier sucking parents. Specifically, parental pacifier sucking appeared to suppress serum IgE levels beginning around 10 months(p=0.048), and continued to diverge through 18 months(p=0.014). Conclusions These results show an association between parental pacifier sucking and lower early-life total IgE production. Further research is needed to assess whether these differences are due to the transfer of parental oral microbes, and if allergic disease risk later in life is sustained. These findings support a previous Swedish study reporting a protective effect of parental pacifier sucking on the risk of allergic diseases in children. Difference in total IgE trajectory by parental sucking of pacifiers - among children who used pacifiers at 6-months of age.