Use of antibiotics in early life and development of diseases in childhood: nationwide registry study.
Level 3 - non-randomized controlled study
Nationwide observational cohort study with sibling-matched analysis
PubMed 40519361 · doi:10.1136/bmjmed-2024-001064
What was done
A nationwide Danish registry cohort study evaluated 518,483 children born between 1998 and 2006 who lived in Denmark during their first year of life without prior disease outcomes, followed for a mean of 13.2 years (SD 3.12). Sibling-matched analyses were conducted in a subgroup of 272,753 children (126,632 sibships) to adjust for shared familial confounding. Cox proportional hazards regression assessed the relationship between systemic antibiotic prescriptions before age one and subsequent development of immune-mediated diseases (asthma, allergy, eczema, coeliac disease, juvenile arthritis, type 1 diabetes) and overweight.
What was found
Overall, 40.3% of children (n=209,013) were prescribed systemic antibiotics before age one. In the full cohort, antibiotic use was linked to an increased risk of several immune-mediated diseases (adjusted hazard ratios 1.20 to 1.53) with an observed dose-response relationship. When analysing sibling pairs, only asthma and eczema remained associated with antibiotic use (adjusted hazard ratios 1.07 to 1.35). No specific trends were found regarding the timing of exposure or antibiotic class.
Why it matters
This study shows that while early-life antibiotic exposure correlates broadly with childhood immune conditions, familial factors likely account for associations with diseases other than asthma and eczema.
Limits
Observational registry design subject to confounding by indication (the underlying infection requiring treatment). The abstract does not report exact point estimates or confidence intervals for individual disease outcomes. Findings in a Danish population may not generalize to settings with different antibiotic utilization patterns or genetic backgrounds.
Cited by
- supports Repeated exposure to antibiotics early in life increases the likelihood of developing allergies and autoimmunity.