Poverty and Awakening Cortisol in Adolescence: The Importance of Timing in Early Life.

The deleterious effects of poverty on mental and physical health are routinely argued to operate, at least in part, via dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis, although empirical examinations connecting poverty with HPA axis functioning are rare. Research on the effects of timing of poverty is a particularly neglected aspect of this relationship. This study uses 15 years of prospective data from the Study of Early Child Care and Youth Development to assess how exposure to poverty during infancy, childhood, and adolescence is related to awakening cortisol (n = 826), a marker of HPA axis functioning. Among female participants, poverty exposure in infancy and adolescence, but not childhood, was negatively associated with awakening cortisol. Poverty exposure was unrelated to cortisol among male participants. The importance of timing and gender differences are discussed along with directions for future research.