Determination of reference values for salivary cortisol in healthy infants aged 0-12 months.

Abstract

Salivary cortisol is a useful tool as a biomarker of stress in pediatrics because it allows for non-invasive sampling. There is little information about its use in children, and no reference values for healthy infants have been reported in Argentina. Reference values should be established at each site as the basis for subsequent tests in infants, for whom salivary cortisol appears to be the most relevant objective tool to assess stress at present. To determine reference values for salivary cortisol in healthy infants aged 0-12 months. Descriptive, cross-sectional study that assessed morning salivary cortisol levels in healthy male and female infants aged 0-12 months that attended Hospital Pirovano for a health checkup between March 2017 and March 2018. Fasting saliva samples were collected between 8 and 9 a.m. and were processed using electrochemiluminescence. Results were reported as mean and standard deviation. A total of 140 infants were included, and 96 samples were collected. Mean morning salivary cortisol levels were 5.46 nmol/L (95 % confidence interval: 4.66-6.38), standard deviation: 2.15. No correlation to age was observed, so it was not necessary to divide the reference range into age groups. No significant differences were observed in terms of sex, gestational age, birth weight, type of delivery or type of feeding. The reference range of morning salivary cortisol levels in healthy infants aged 0-12 months was reported.