Infant hair cortisol: associations with salivary cortisol and environmental context

Abstract

Early chronic stress has enduring implications for physical and mental health outcomes. Hair cortisol concentration (HCC) has emerged as a marker of cumulative cortisol exposure, yet HCC in infants is not well understood. We examined how infant HCC relates to widely used basal salivary cortisol measures, maternal HCC, and environmental context in 111 infants assessed at 6 and 12 months of age. Maternal HCC at 6 and 12 months was correlated with infant HCC at 12 months. At 12 months, infant HCC was positively associated with waking salivary cortisol concentration (SCC), evening SCC, and area under the curve (AUC), but was independent of diurnal slope. Breastfeeding was associated with lower HCC, whereas increased sleep disruption was related to flatter slope. Reduced nighttime sleep duration was related both to higher HCC and to flatter slope. A person-focused analysis indicated that the combination of high HCC and flattened slope was associated with more environmental risks, highlighting the importance of investigating the interplay between HCC and diurnal cortisol slope. Results support the validity of HCC as a marker of cumulative cortisol exposure in infancy, while emphasizing the value of including multiple cortisol measures assessing distinct aspects of Hypothalamic-Pituitary-Adrenal (HPA) function.

Hair cortisol as a measure of the stress response to social adversity in young children

“…In 11 studies that examined between one and four indicators of adversity, four reported no associations with hair cortisol (Boeckel et al, 2017;Flom, et al, 2017;Gerber et al, 2017;Olstad et al, 2016), five reported associations with one indicator (Ouellette et al, 2015;Palmer et al, 2013;Ursache et al, 2017;Vaghri et al, 2013;Vliegenthart et al, 2016), and two studies reported associations with two indicators (Rippe et al, 2016;Windhorst et al, 2017). Where associations are reported, often they are not replicated by other studies.…”

Maternal Stress During Pregnancy Is Associated with Decreased Cortisol and Cortisone Levels in Neonatal Hair

“…In addition, the small sample size did not allow us to test associations by type of SAD. Lastly, ideally other tests of HPA axis activity, relating to HPA axis reactivity and rhythmicity, should have been included too [46]. …”

Annual Research Review: Early adversity, the hypothalamic–pituitary–adrenocortical axis, and child psychopathology

“…Typically, no more than 3 cm is examined as cortisol leaches from the hair with washing and hair treatments. In infants, hair cortisol is positively related to waking and bedtime levels and total magnitude of cortisol across the day, but not the diurnal slope (Flom, St. John, Meyer, & Tarullo, ).…”