Background: Human scalp hair is a valuable matrix for determining long-term cortisol concentrations, with wide-spread applicability in clinical care as well as research. However, pediatric reference intervals are lacking.The aim of this study is to establish age-adjusted reference intervals for hair cortisol in children aged 0-18 years and to gain insight into hair-growth velocity in children up to 2 years old.
Methods: A total of 625 healthy children were enrolled through recruitment in pregnancy, infant-welfare clinics, and school visits. Scalp hair cortisol levels were measured using liquid chromatography-tandem mass spectrometry. Age-adjusted reference intervals were established. Hair-growth velocity was determined in children 0-2 years by measuring hair length with a 4 to 10 week interval.
Results: Hair cortisol levels were high (162.4 pg/mg) after birth with a sharp decrease in the first months of life, followed by a slow decrease until age 5 after which a subtle increase occurs until adult concentrations are reached at the age of 18 years (3.0 pg/mg). Average hair growth velocity measured in mm/months was significantly lower infants (0-6 months) compared to children (12-24 months) (3.5 versus 9.4, P<0.001).
Conclusions: This is the first study to provide age-adjusted reference intervals for hair cortisol in children from 0-18 years. Higher hair cortisol concentrations in infants might be explained by the significant lower hair growth rate in the first year of life. The establishment of pediatric hair cortisol reference ranges broadens the potential applications of this biomarker in both clinical practice and research.
Commentary: The abstracts 225: Establishment of Reference Intervals for Hair Cortisol in Healthy Children Aged 0-18 Years Using Mass Spectrometric Analysis and 227: "Help my baby cries!" hair cortisol as marker for parental stress in excessive crying infants are an important part of my pHD trajectory concerning "early live stress" supervised by Dr Erica van den Akker. As hair cortisol analysis is increasingly being applied in both research and clinical practice, a combination of the results of these 2 abstracts would be very suitable for an oral presentation and interesting for both attending clinicans and researchers.
19 - 21 Sep 2019
European Society for Paediatric Endocrinology