Prenatal and postnatal inflammation in relation to cortisol levels in preterm infants at 18 months corrected age

Abstract

Objective: To examine whether early inflammation is related to cortisol levels at 18 months corrected age (CA) in children born very preterm.

Study design: Infants born ≤ 32 weeks of gestational age were recruited in the neonatal intensive care unit (NICU), and placental histopathology, magnetic resonance imaging (MRI) and chart review were obtained. At 18 months CA, developmental assessment and collection of three salivary cortisol samples were carried out. Generalized least squares was used to analyze data from 85 infants providing 222 cortisol samples.

Result: Infants exposed to chorioamnionitis with funisitis had a significantly different pattern of cortisol across the samples compared with infants with chorioamnionitis alone or no prenatal inflammation (F(4, 139)=7.3996, P<0.0001). Postnatal infections, necrotizing enterocolitis and chronic lung disease were not significantly associated with the cortisol pattern at 18 months CA.

Conclusion: In children born very preterm, prenatal inflammatory stress may contribute to altered programming of the hypothalamic-pituitary-adrenal (HPA) axis.

Figure 1. Study Participants Flow Chart

Figure 2. Cortisol Pattern by Prenatal Infection Group

Cortisol across assessment phase (pretest, post-1 and post-2) by prenatal infection group: no infection (n=54), chorioamnionitis alone (n=13) and chorioamnionitis with funisitis (n=11). The lower and upper quartiles are represented by the top and bottom limits of each box, and the minimum and maximum data values by the “whiskers”. The median is represented by the bold line. Outliers (represented as points outside “whiskers”) were identified if they surpassed the upper or lower quartile by more than 1.5 times the inter-quartile range (IQR).