Racism and hypothalamic-pituitary-adrenal axis functioning in childhood as risks for health disparities across the lifespan

Racism is a primary social determinant of health and chronic stressor that affects the physical and mental health of People of Color and Indigenous Individuals (POCI) and perpetuates racial and ethnic health disparities. Despite the impact of racism on POCI, the mechanisms through which experiences of racism result in negative health outcomes remain understudied, in particular among children. Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is one of the possible mechanisms. Frequent and prolonged exposure to chronic stressors may result in dysregulation of the HPA axis, and in turn cause adverse physical and psychological health outcomes for POCI children. This paper argues for the importance of examining HPA axis dysregulation as a mechanism that links racism during early childhood to negative health outcomes over the lifespan. Several studies have explored the relationship between racism and HPA axis dysregulation during adulthood and adolescence and have found associations between racism and salivary and hair cortisol. Recent studies have identified racial and ethnic differences in cortisol levels during early childhood, but only one study, to our knowledge, explored whether the differences are attributed to racism. In this paper, we conduct a review of the existing literature on the links between racism and HPA axis dysregulation during adulthood and adolescence given the dearth of studies exploring this relationship during early childhood. We also highlight the importance of utilizing an intersectionality framework in the study of racism and health to provide a more comprehensive and nuanced understanding of health disparities among and within racial/ethnic groups. Using this evidence along with consideration of relevant models, we propose how HPA axis dysregulation identified early in life may foreshadow children's increased risk for negative health outcomes from racism and other systems of oppression and signal the need for prevention and intervention.