Low Apgar score in term newborns and long-term infectious morbidity: a population-based cohort study with up to 18 years of follow-up

Since introduced, the Apgar score has remained the most widespread predictor for neonatal morbidity and mortality. We aimed to investigate the association between low 5-min Apgar score and long-term infectious pediatric morbidity. A population-based cohort analysis was performed comparing total and specific subtypes of infectious morbidity leading to hospitalization among term newborns with normal (≥ 7) and low (< 7) 5-min Apgar scores, born between 1999 and 2014 at a single tertiary regional hospital. Infectious morbidity included hospitalizations involving a pre-defined set of infection-related ICD-9 codes. A Kaplan-Meier survival curve was constructed to compare cumulative infectious morbidity incidence and a Cox proportional hazards model to adjust for confounders. The long-term analysis of 223,335 children (excluding perinatal death cases) yielded 585 (0.3%) infants with low 5-min Apgar scores. The rate of infection-related hospitalizations was 9.8% and 12.4% among newborns with normal and low 5-min Apgar scores, respectively (p = 0.06). Adjusting for maternal age, gestational age, hypertension, diabetes, cesarean delivery, and fertility treatments, the association proved to be statistically significant (adjusted HR = 1.28; 95% CI 1.01–1.61).