Poor sleep and altered hypothalamic-pituitary-adrenocortical and sympatho-adrenal-medullary system activity in children

Abstract

Context: Neuroendocrine alterations, with well-known links with health, may offer insight into why poor sleep is associated with poor health. Yet, studies testing associations between sleep and neuroendocrine activity in children are scarce. Objective: The aim of this study was to determine whether actigraphy-based sleep pattern is associated with hypothalamic-pituitary- adrenocortical axis and sympatho-adrenal-medullary system activity in children. Design and Setting: We conducted a cross-sectional study in a birth cohort in Helsinki, Finland. Participants: We studied 282 8-yr-old children. Main Outcome Measures: We measured diurnal salivary cortisol and salivary cortisol and α-amylase (a sympatho-adrenal-medullary system marker) responses to the Trier Social Stress Test for Children (TSST-C). Results: Children with short (≤7.7 h) vs. average sleep duration (7.8-9.3 h) displayed higher cortisol awakening response and nadir (P<0.042). Those with low (≤77.4%) vs. average-high sleep efficiency (>77.4%) displayed higher diurnal cortisol levels across the entire day (P<0.03), higher cortisol levels after the TSST-C stressor (P<0.04), and higher overall α-amylase levels across the entire TSST-C protocol (P < 0.05). The effects were not confounded by factors that may alter sleep or hormonal patterns. Conclusions: Poor sleep may signal altered neuroendocrine functioning in children. The findings may offer insight into the pathways linking poor sleep with poor health. Copyright © 2010 by The Endocrine Society.