Gut Microbiome Maturation Protects Against Allergic Manifestations in Early Childhood

Sep 26, 2023

Maturing infant gut microbiota is associated with lower childhood risk for allergy-related wheezing and asthma.

Babies with a mature gut microbiome are less likely to develop allergy-related wheezing and asthma in early childhood. This showed a subgroup analysis including 323 babies of the Australian Barwon Infant Study (BIS), the results of which were presented at the 2023 ERS International Congress.

After birth, the diversity of microbiota increases and matures as babies grow older and are exposed to microbiota from other sources, such as other children, animals, and different foods. Previous studies have shown that delayed gut microbiota maturation in the first year of life is a hallmark of pediatric allergic diseases.

“In our study, we examined the relationship between the maturation of the infant gut microbiota in the first year of life and subsequent atopic wheeze in childhood in the BIS cohort,” explained Yuan Gao, PhD. The BIS has been active in Australia since 2010 and enrolled 1,074 babies between 2010 and 2013 who were followed up. At the 1-year and 4-year postnatal reviews, the BIS investigators evaluate whether children had developed allergy-related wheezing or asthma in the previous 12 months, according to reports of their parents. In addition, skin-prick tests were performed to test for food allergies or airborne substances.

For the current study, Dr. Gao and her colleagues selected a sub-group of 323 children of the BIS cohort and collected fecal samples one month after birth, 6 months after birth, and at 1 year of age. Microbiota in the samples were assessed using a DNA sequencing technique (16S rRNA gene amplicon sequencing). With the results, the researcher calculated a “microbiota-by-age z-score” (MAZs), which is a mathematical estimate of the maturity of the children´s gut microbiota.

Each SD increase in MAZ at 1 year of age was associated with decreased odds of atopic wheeze at 1 and 4 years. Babies who had more mature gut microbiota had about 50% reduced risk for allergy-related wheeze at 1 and 4 years. In contrast, this association was not found in MAZ scores at 1 or 6 months. “The take-home message is that advanced maturation of the infant gut microbiota in late infancy is associated with reduced odds of atopic wheeze during childhood,” Dr. Gao concluded.