Early-Life Poverty and Awakening Cortisol in Adolescence: Examining Cumulative Exposure and Timing

The deleterious effects of poverty vis-à-vis 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. The timing of poverty represents a particularly neglected aspect of this relationship. This study utilizes prospective data from the Study of Early Child Care and Youth Development (SECCYD) to test how the timing of and cumulative exposure to poverty are associated with awakening cortisol (N=826). I found that among females, poverty exposure in both infancy and adolescence was negatively associated with awakening cortisol. Moreover, while cumulative exposure was initially found to be negatively associated with awakening cortisol, its effects were explained by the timing of exposure. Poverty exposure was unrelated to cortisol among males. The implications regarding cumulative exposure and timing as well as windows of vulnerability to poverty are discussed.