Low apgar score in term newborns and long term gastro-intestinal morbidity, a population based cohort study with up to 18 years of follow up

Objective
Low Apgar scores (<7) measured at age 5 minutes can predict short- term infant morbidity and mortality. We aimed to study the possible association between low 5 minutes Apgar scores in term newborns and their long-term gastro-intestinal (GI) related morbidity, during a follow- up of up to 18 years.

Study Design
A population based cohort analysis was performed comparing total and different subtypes of GI related pediatric hospitalizations (up to the age of 18 years) among newborns with normal (≥7) and low (<7) 5 minutes Apgar scores. The analysis included all term singletons born between the years 1999-2013 at a single tertiary regional medical center. Infants with congenital malformations and all perinatal deaths were excluded from the long term analysis. GI related morbidities included hospitalizations involving a pre-defined set of ICD-9 codes, as recorded in the hospital medical records. A Kaplan-Meier survival curve was constructed to compare the cumulative GI morbidity, and a Cox proportional hazards model was used to adjust for suspected confounders.

Results
The study population, including 223 224 term singletons, was followed for an average of 10.02±6.04 years (0- 18 years, median 10.25) following discharge from birth hospitalization. Low 5 minutes Apgar scores were measured in 585 (0.3%) newborns and normal Apgar in 222 659 (99.7%) newborns. Incidence of GI related hospitalizations was higher among the low vs. the normal 5 minutes Apgar score group (7.4% vs. 5.2%; 8.6/1000 person years (PY) vs. 5.2/1000 PY; p=0.02; incidence density ratio= 1.66, 95% CI 1.36-1.96; Kaplan-Meier log of survival presented in the graph, p=0.003). Selected GI morbidities are presented in the table. The association between low 5 minutes Apgar score and GI morbidity remained significant while adjusting for maternal age, hypertension during pregnancy and gestational diabetes, using a Cox proportional hazards model (Adjusted HR= 1.57, 95%CI 1.16-2.12, p=0.003).

Conclusion
Low 5 minutes Apgar scores are associated with higher long-term pediatric GI morbidity of the offspring. Our results suggest that Apgar scores can be used as a possible risk factor for long term pediatric morbidities.