Atopic Eczema in Infants Linked to Antibiotic Exposure in First Year

Postnatal antibiotic use has been linked to a greater risk of atopic eczema among infants in a new study published in Pediatric Allergy and Immunology.

Still, the investigators stress that uncertainty remains of the direction of this relationship: Is the antibiotic exposure the cause of the infantile eczema or did the skin condition lead to the antibiotic exposure?

“The risk of developing atopic eczema is influenced by various events pre-conception, during pregnancy, and throughout the neonatal period,” the study authors wrote. “Recent reports have suggested that early life exposure to microbiome altering medications, such as antibiotics and laxatives, could impact the risk of atopic eczema in infancy and childhood.”

Study data were from the Southampton Women’s Survey in the United Kingdom. Of the original 12,583 nonpregnant women initially recruited, 3158 became pregnant and were followed for the duration of their pregnancy. Gestational antibiotic and laxative exposures were evaluated at 2 points: 11.8 and 34.5 weeks’ gestation, for late and early in pregnancy, respectively.

The total patients reporting exposure to both microbiome-altering medications increased from the early to the late period. At 11.8 weeks, 7.9% reported antibiotic exposure and by 34.5 weeks this had risen to 9.6%. For laxative exposure, the corresponding rates were 2.1% and 2.3%.

The children (n = 2867) were then evaluated at age 12 months, and 50% had recorded antibiotic exposure. Among this group, early-pregnancy maternal antibiotic exposure was reported in 10.1% and late-pregnancy maternal antibiotic exposure in 12.3%. In addition, maternal laxative use was reported for 2.5% and 3.4% in early and late pregnancy, respectively.

For a potential link to atopic eczema at ages 6 and 12 months, the investigators used the UK Working Party Criteria for the Definition of Atopic Dermatitis. Among the 5777-infant cohort, 262 had eczema by 6 months and 270 by 12 months.

“We used Directed Acyclic Graphs (DAGs) to identify potential confounders and competing exposures that should be included in our statistical models to support causal interpretation,” the authors noted.

From this, they determined that maternal body mass index, parity, breastfeeding duration, and infant sex showed a causal relationship between maternal laxative and antibiotic use and appearance of infant atopic eczema. An additional analysis of infant antibiotic use and appearance of atopic eczema showed a potential relationship between the skin condition and maternal education, parity, breastfeeding duration, and infant sex.

Univariate and multivariate analyses did not show a relationship between maternal antibiotic use and infantile atopic eczema, nor between maternal laxative use and infantile eczema at 6 and 12 months. However, there was a 59% (HR, 1.59; 95% CI, 1.23-2.07; P = .001) greater risk of atopic eczema at age 12 months from use of antibiotics in infancy.

Compared with no antibiotic exposure, similar risks for atopic eczema were seen in those with exposure in their first 6 months of life vs from 6 to 12 months. Further, the greater the antibiotic use, the greater the odds of atopic eczema. One exposure equated to a 51% (HR, 1.51; 95% CI, 1.11-2.04; P = .008) greater risk and 2 to 3 and more than 3 exposures to 64% greater risks each (HR, 1.64; 95% CI, 1.15-2.33; P = .006 and HR, 1.64; 95% CI, 0.97-2.7776; P =.6607, respectively).

“The findings support evidence that postnatal antibiotic exposure is associated with the infant's risk of developing atopic eczema,” the authors concluded. “These findings from a single observation have limited generalizability, but coupled with the results of recent studies we recommend further research to examine the impact of early life antibiotic and laxative exposure on the microbiome-immune-atopy axis.”

Reference

El-Heis S, Crozier SR, Harvey NC, Healy E, Godfrey KM. Early life exposure to antibiotics and laxatives in relation to infantile atopic eczema. Pediatr Allergy Immunol. Published online May 26, 2023. doi:10.1111/pai.13964