Parents' psychological stress over time may affect children's cortisol at age 8.

OBJECTIVE To examine possible relations between parents' psychological stress and children's saliva cortisol levels in connection with a mild stressor (drawing a blood sample). METHOD Parenting stress and serious life events at birth, age 1, age 2, age 5, and age 8 were assessed. Eighty-two paired saliva samples collected from their 8-year-old children just before and 30 min after blood was drawn were analyzed. RESULTS Instead of increasing, cortisol levels significantly decreased. Repeated measures GLM indicated a significant relation between higher parenting stress at child age 1 and at age 8, and elevated cortisol levels. A t-test indicated that cortisol levels after the blood draw were significantly higher in children whose parents reported a serious life event at age 8. CONCLUSION Parenting stress could be a relevant factor for children's adjustment of the HPA axis with long-term effects and leave children more vulnerable to experiences of stress.