Influence of antibiotic use in early childhood on asthma and allergic diseases at age 5.

BACKGROUND: In the past few decades, the prevalence of allergic diseases has increased rapidly worldwide. At the same time, the overuse of antibiotics has been observed, especially in Japan.

OBJECTIVE: To elucidate the association of early childhood antibiotic use with allergic diseases in later childhood at 5 years of age.

METHODS: Relevant data were extracted from the hospital-based birth cohort study, the Tokyo Children's Health, Illness and Development Study. To identify signs of asthma and allergic diseases in children, the International Study of Asthma and Allergies in Childhood questionnaire was used. Logistic regression models were applied to estimate the effect of antibiotic use on outcomes in later life.

RESULTS: Antibiotic exposure in children within the first 2 years of life was associated with current asthma (adjusted odds ratio [aOR] 1.72, 95% confidence interval [CI] 1.10-2.70), current atopic dermatitis (aOR 1.40, 95% CI 1.01-1.94), and current allergic rhinitis (aOR 1.65, 95% CI 1. 05-2.58) at 5 years of age. Analysis of the associations by type of antibiotics showed that cephem was associated with current asthma (aOR 1.97, 95% CI 1.23-3.16) and current rhinitis (aOR 1.82, 95% CI 1.12-2.93), and macrolide was associated with current atopic dermatitis (aOR 1.58, 95% CI 1.07-2.33).

CONCLUSION: Our findings suggest that antibiotic use within the first 2 years of life was a risk factor for current asthma, current atopic dermatitis, and current allergic rhinitis in 5-year-old children.