Longitudinal Evaluation of Salivary Cortisol Levels in Full-Term and Preterm Neonates

Abstract

The aim of the present study was to test the practicability of sequential cortisol determinations in saliva of low birth weight neonates and to evaluate the impact of systemic and inhaled glucocorticoid therapy on saliva concentrations of cortisol in preterm neonates with bronchopulmonary dysplasia (BPD). Salivary cortisol levels were measured by RIA in saliva samples from 10 full-term and 10 preterm healthy neonates and from 20 preterm neonates with BPD during systemic [dexamethasone (DEX); n = 10] or topical steroid therapy [budesonide (BUD); n = 10]. Saliva samples of each individual were collected on 3 consecutive days at 06.00, 12.00, 18.00 and 24.00 h. Cortisol levels in saliva ranged from 0.8 to 60.6 nmol/l (median 6.5 nmol/l) in full-term neonates, from 0.6 to 52.1 nmol/l (median 5.5 nmol/l) in preterm neonates, from 0.4 to 14.0 nmol/l (median 1.0 nmol/l) in preterm neonates treated with DEX and from 0.4 to 15.2 nmol/l (median 2.5 nmol/l) in preterm neonates treated with BUD. Autocorrelation analysis revealed a distinct endogenous cortisol rhythm in 2 of the 10 healthy full-term neonates and in 3 of the 10 healthy preterm neonates with a wavelength of 12–30 h. Salivary cortisol levels in preterm neonates treated with DEX or BUD were significantly lower than those measured in healthy preterm neonates. These results demonstrate that the measurement of salivary cortisol levels is a reliable and practicable way of assessing adrenal function in full-term and preterm neonates. This study also shows for the first time that some neonates display an endogenous cortisol rhythm which is not coupled to the exogenous day/night cycle. Furthermore, systemic and nebulized glucocorticoids suppress adrenal function in low-birth-weight neonates. After treatment these children should be closely monitored for potential adrenal insufficiency.

Multi-year longitudinal profiles of cortisol and corticosterone recovered from baleen of North Atlantic right whales (Eubalaena glacialis)

“…Serial plasma samples collected over time from the same individuals (i.e., longitudinal sampling) have been particularly informative for clarifying relationships of GCs with a multitude of potentially important natural and anthropogenic stressors. Longitudinal sampling enables detailed study of cycles in GC secretion, relationships of GCs to long-lasting reproductive states such as pregnancy or lactation, and can help discriminate cases of chronic vs. acute stress events (e.g., Bettendorf et al, 1998;Grant et al, 2016;Koester et al, 2015;Reeder et al, 2004).…”

Relationship of Salivary and Plasma Cortisol Levels in Preterm Infants: Results of a Prospective Observational Study and Systematic Review of the Literature

“…Saliva collection is easy to perform and reliable in adults and older children wherefore salivary concentrations of cortisol reflecting free cortisol concentrations in plasma is used to evaluate adrenal cortex function [4][5][6][7] . The best method of assessing adrenal function in preterm infants still is under debate but salivary cortisol measurement seems to be a promising diagnostic feature for these infants, too [8][9][10] .…”

Stress : Clinical and Developmental Aspects of Salivary Cortisol in Infants

“…TCM has previously been shown to affect cortisol levels in preterm infants with respiratory diseases [198,199] concluded that infants exposed to tobacco in utero had elevated ACTH levels [131] while Saridjan et al, noted an effect on cortisol variability among children age 14 months whose mothers smoked [101]. The number of smoking mothers were only three (all in paper IV) throughout the material and no mother used snuff.…”