Infant Antibiotic Exposure Is Associated With Increased Risk of Later Childhood Infections, Antibiotic Use and Asthma

Antimicrobials have saved millions of lives. Antibiotics are essential in treating infant infections, but may disrupt the gut microbiome and have adverse effects on later health.

This population-based birth cohort study included full-term children born in Iceland from 2010 to 2019 with follow-up for 2-12 years. The cohort was divided into 4 groups according to antibiotic exposure; I: elective cesarean section, II: vaginal birth and maternal intrapartum antibiotics, III: vaginal birth and infants received antibiotics during the first week of life for >48 hours and IV: vaginal birth without antibiotic exposure. Rates of infections, antibiotic use and the risk of asthma later in childhood were calculated.

Of 43,600 children born in Iceland from 2010 to 2019, 22,393 were included. Group I had 1496 children, group II 3413, group III 356 and group IV 17,128 children. For all antibiotic exposure groups, the risk of infections and antibiotic use was significantly higher (20%-100%), with the largest effect observed for infants treated with antibiotics. This group also had a 2-fold risk of asthma diagnosis when compared with controls (odds ratio: 1.91, P < 0.05).

In this cohort study, children with early antibiotic exposure had higher rates of infections and antibiotic use later in childhood compared with controls. Diagnoses of asthma were significantly more common in children with early antibiotic exposure and this effect was most evident after the age of 8 years. The observed late side-effects of antibiotic use, possibly mediated through a disrupted microbiome, should promote a conservative approach to antibiotic treatment in young infants.