Heart rate variability and salivary cortisol in very preterm children during school age

摘要

Highlights ? Children born very preterm had lower LF/HF ratio during wake and stage 2 sleep. ? LF, Tot Pow, and LF/HF ratio were positively related with morning cortisol secretion. ? The results indicate long-term ANS alterations after very preterm birth. ? The results support the notion of a feedback system between the ANS and the HPA axis. Abstract The autonomic nervous system (ANS) plays a major role in the human stress response and reflects physical and psychological adaptability to a changing environment. Long-term exposure to early life stressors may alter the function of the ANS. The present study examines differences in the ANS between children born very preterm and full-term as well as the association between the ANS and the hypothalamic-pituitary-adrenal (HPA) axis, the other main branch of the human stress system. Fifty-four healthy children born very preterm ( Children born very preterm had lower LF/HF ratio during wake and stage 2 sleep compared to full-term children. Moreover, higher LF, Tot Pow, and LF/HF ratio during wake, stage 2 sleep, and REM sleep were related to more post-awakening cortisol secretion. The present study provides evidence on long-term ANS alterations after very preterm birth. Moreover, findings suggest a relation between the ANS and the HPA axis and therefore support the notion of mutual feedback between the two human stress systems.