- Antibiotic administration in infants is tied to increased risk for allergy in childhood, with the risk increasing with increasing types of antibiotics used.
- Association was seen with all antibiotics assessed in this study.
Why this matters
- Antibiotic administration likely alters the microbiome, and these alterations in turn have been tied to allergy.
- These authors suggest that the association might strengthen with each additional antibiotic used in infancy.
- The most commonly prescribed class of antibiotics was penicillins (59.5%).
- Most children in this cohort (83.3%) were not prescribed any antibiotic.
- 13.7% were prescribed 1 class, 2.5% were prescribed 2 classes, 0.44% were prescribed 3 classes, and 0.06% were prescribed 4+.
- Each class of antibiotics was tied to increased risk (adjusted HRs; 95% CIs) for allergy in childhood.
- Risk was lowest with sulfonamide (1.06; 1.03-1.10) and highest with penicillin (1.30; 1.28-1.31).
- With each additional class, these risks increased for each type of allergy (e.g., food, atopic dermatitis, anaphylaxis, allergic rhinitis).
- These associations persisted even when adjusted for total days prescribed.
- Retrospective cohort study, analysis of prescription data for 798,426 children (beneficiaries of the US armed forces insurance).
- Funding: Study was performed at Uniformed Services University of the Health Sciences.
- Reverse causality is possible.