Salivary and serum cortisol levels in newborn infants

PAPAZIAN, R; FALCO, S; FORCLAZ, VERÓNICA; BERGADÁ, I; OLSEN, G; MORATO, E; RODRIGUEZ, P; PENNISI, A

ARCHIVOS ARGENTINOS DE PEDIATRIA

SOC ARGENTINA PEDIATRIA

Lugar: Buenos Aires; Año: 2017 vol. 115

0325-0075

Introduction. Given that serum cortisol levelinterpretation in newborn infants (NBIs) ishard, the objective of this study was to correlatebaseline salivary and serum cortisol levels andto describe salivary cortisol levels in the firstmonth of life.Population and Methods. Descriptive,prospective, longitudinal, and correlationalstudy. Term NBIs were selected from theDivision of Neonatology of Hospital NacionalProfesor Alejandro Posadas in 2014. Cortisolwas measured in saliva specimens whilecortisol, cortisol-binding globulin, and albuminwere measured in blood specimens. A linearcorrelation was performed to relate serumand salivary cortisol levels; Friedman test wasconducted to compare cortisol levels during thefirst month of life, and the difference was usedto analyze the performance of values equal to orlower than the first quartile.Results. Fifty-five NBIs were studied. Serumcortisol: 7.65 (1.0-18.1 μg/dL); salivary cortisol:35.88 (5.52-107.64 mmol/L); cortisol-bindingglobulin: 22.07 (16.5-33.0 μg/mL), expressed asmedian and range. The correlation coefficientbetween serum and salivary cortisol was 0.54,P = 0.001. Cortisol performance during the firstmonth of life showed no statistically significantdifferences, and the difference between thesecond and the first specimen of values equalto or lower than the first quartile increased in10 out of 12 patients.Conclusion. The measurement of cortisol insaliva reflects serum cortisol levels in normalNBIs. Some patients had low levels of cortisolat 36 hours of life and showed a trend towardsa spontaneous increase during the first monthof life.