Childhood environment early life stress, caregiver warmth, and associations with the cortisol diurnal curve in adulthood: The coronary artery risk development in young adults (CARDIA) study

Background: Early life stress (ELS) is associated with increased morbidity and mortality across the lifecourse. Studies observing a relationship between ELS and stress physiology (cortisol), may help explain the connection to poor health outcomes, but have been limited by cortisol measures used.Purpose: We examined the association between ELS measured by a Risky Family (RF) environment questionnaire, and adult diurnal cortisol profile inclusive of multiple cortisol measures.Methods: RF and cortisol were collected from Coronary Artery Risk Development in Young Adults Study par-ticipants at follow-up (Year 15). Complete case (n = 672) data were included in multi-variable regression an-alyses with log transformed cortisol measures (outcomes) including wake-up cortisol, cortisol awakening response [CAR], AUC and five other cortisol diurnal curve measures. Results: Participants were age 39.9 + /-3.7 years and 51.6% Black. For every 1 unit increase in RF, there was a 1.4% greater wake-up cortisol and flatter CAR after adjustment for age, sex, income, and smoking (B=0.014, p = 0.023; B=-0.014, p = 0.028, respectively). Each unit increase in caregiver warmth/affection was associated with a 6.9% higher (steeper) CAR (B=0.069, p = 0.03). Results remained significant after adjusting for other covariates except social support in adulthood. An interaction between child abuse and caregiver warmth was nearly significant (p = 0.068), such that for those with exposure to the greatest caregiver warmth and lowest child abuse, CAR was steepestConclusions: We demonstrate that ELS is associated with altered cortisol regulation in adulthood. However, further research is needed to assess how healthy relationships throughout the life course may modulate cortisol regulation in adulthood.