Gestational age and obstructive sleep apnea of the term offspring: is later better?

Objective
Childhood obstructive sleep apnea (OSA) may have severe long-term consequences. Known risk factors include a history of preterm delivery. We sought to determine whether the different subgroups of ‘term’ delivery impact differently on the prevalence of childhood OSA.

Study Design
In this population-based cohort analysis all term singleton deliveries occurring between 1991-2013 at a single tertiary medical center were included. Gestational age upon delivery was sub-divided into: early (37-38+6 weeks’ gestation), full (39 - 40+6 weeks’ gestation), late (41 - 41+6 weeks’ gestation) and post term (>42 weeks). Fetuses with congenital malformations were excluded. The rate of OSA related hospitalizations up to the age of 18 was assessed in the different categories of gestational age, and cumulative rates compared using Kaplan-Meier survival analysis. Cox proportional hazard models were used to study the association between gestational age at birth and the risk for OSA related hospitalization, while controlling for potential confounders.

Results
During the study period 225 260 term deliveries met the inclusion criteria. OSA related hospital encounters up to the age of 18 years (n=1194) were significantly more common in the early term delivery group (0.7%) and decreased in the full (0.5%), late (0.4%), and post term (0.3%) groups (p<0.001; using the chi-square test for trends). In the Cox model, as compared to full term deliveries, early term delivery exhibited an independent association with pediatric OSA (adjusted HR-1.33 95%CI 1.16-1.52, p<0.001, Table, Figure) while late and post term deliveries were associated with significantly lower OSA hazard ratios (adjusted HRs of 0.79 95%CI 0.67-0.94 and 0.60 95%CI 0.41-0.86, respectively, p<0.05).

Conclusion
Deliveries occurring at early term are associated with higher rates of pediatric OSA related hospitalizations which decrease gradually as gestational age advances.