Early antibiotic exposure and necrotizing enterocolitis among preterm infants < 34 weeks' gestation

To investigate whether use, duration, and types of early antibiotics were associated with the risk of necrotizing enterocolitis (NEC) among preterm infants born at <34 weeks' gestation.

This multicenter prospective cohort study included all infants with gestational age <34 weeks and admitted to neonatal intensive care units across China. Early antibiotic exposure was defined as the antibiotic treatment initiated within the first three postnatal days. The short-term outcomes included death, NEC, death and/or NEC. Propensity score matching was performed to generate matched cohorts. The impacts of early antibiotics exposure on the outcomes were evaluated by univariate and multivariate logistic regression models.

Among 24,926 eligible infants, 20164 (80.9%) received early antibiotics. After matching, early antibiotics exposure was not significantly associated with the death and/or NEC (adjusted OR, 0.93; 95%CI, 0.72-1.21), NEC (adjusted OR, 0.81; 95% CI, 0.60 -1.10) or death (adjusted OR, 1.42; 95% CI, 0.90-2.25). However, prolonged antibiotic treatment (adjusted OR, 2.95; 95% CI, 1.67-5.22), especially broad-spectrum antibiotics exposure (adjusted OR, 5.09; 95% CI, 1.84-14.10), was independently associated with death.

While early antibiotics exposure was not associated with the risks of NEC, prolonged antibiotic duration, especially broad-spectrum antibiotics, was associated with a higher mortality.

This multicenter cohort study sheds light on whether use, duration, and types of early antibiotics were associated with the risk of necrotizing enterocolitis among preterm infants <34 weeks of gestation. In preterm infants, early antibiotics exposure was not significantly associated with the risks of death and/or NEC. However, prolonged antibiotic duration, especially broad-spectrum antibiotics, was associated with a higher mortality. Our study emphasizes the importance of neonatal antimicrobial stewardship in improving the prognosis of premature infants.