Longitudinal changes in body mass index Z-scores during infancy and risk of childhood allergies

BACKGROUND

Few studies address the dynamic changes of body mass index (BMI) Z-scores during infancy with breastfeeding and their impact on childhood atopic diseases.

METHODS

A total of 183 children from a birth cohort regularly followed-up for 4 years were enrolled in this study. Time series data of BMI Z-scores from 1 month to 2 years of age was clustered using K-means method in R software. Breastfeeding status during the first 6 months of life was recorded and classified. The total serum and specific immunoglobulin E (IgE) levels to food and inhalant allergens were measured at age 0.5, 1, 1.5, and 2 years.

RESULTS

Using K-means clustering, the dynamic changes in BMI Z-scores were classified into three clusters (cluster A, increasing, n = 62; cluster B; decreasing, n = 62; cluster C, constant low, n = 59). Despite having no statistical association with atopic diseases, a decreasing trend in infantile BMI Z-scores was significantly associated with a higher prevalence of IgE sensitization at age 1 which increased the risk of rhinitis development at age 4 (P = 0.007). No difference in BMI Z-scores was determined between different breastfeeding patterns. However, exclusive formula feeding ≥6 months was found to be significantly associated with mite sensitization at age 1.5 years which risks asthma development at age 4 (P = 0.001).

CONCLUSIONS

A decreasing trend of BMI Z-scores during infancy is determined to be inversely associated with IgE and allergen sensitization, which may potentially increase the risk of allergies in early childhood.

[Research advances in influencing factors for immune tolerance to food allergens in children]

Food allergen-specific immune tolerance is defined as nonresponsiveness of the adaptive immune system to food antigens. Failed development or inhibition of such tolerance may cause food allergy. With the increasing incidence rate of food allergy year by year, more and more studies have found the association between food allergy and various diseases. The development of food allergen-specific immune tolerance in childhood has been taken more and more seriously. In recent years, many studies have shown that the development of food allergen-specific immune tolerance is influenced by various factors, which can be roughly divided into antigens, organisms, and environment. This article reviews the influencing factors for the development of immune tolerance to food allergens in children, in order to provide help for reducing the incidence of food allergy and improving the prognosis of food allergy.