UC Irvine

Discrimination is a common social problem that that been associated with a variety of negative health consequences. Stress from discrimination experiences and resulting physiological changes have been implicated in the pathway to disease. The role of the hypothalamic-pituitary-adrenal (HPA) axis in this process remains understudied. This dissertation addresses the deficiencies in the literature in two parts. First, a systematic review of the literature was conducted. Ten experimental and 17 observational studies met inclusion criteria. Studies suggest that discrimination is associated with alterations in HPA axis activity, and that the direction of this association depends on the timing and chronicity of the discrimination experience. There is also evidence of important modulating variables (race, socioeconomic status) and contextual confounders (emotional, situational) that warrant further study. The second study tested associations between Latino ethnicity, experiences of discrimination, and cortisol responses to an acute laboratory stressor. One hundred and fifty eight individuals (92 female, 66 male) between the ages of 18 and 29 years participated in the study. Salivary cortisol was measured before and repeatedly after the laboratory stressor, and prior discrimination experiences was measured with the Experiences of Discrimination Scale. A moderated mediation emerged, such that Latino ethnicity predicted heightened cortisol reactivity through discrimination experiences (mediator), and this effect was further moderated by sex, with a significant indirect effect only among males. Of note, the direct path from Latino ethnicity to cortisol reactivity did not emerge as significant. Findings suggest that Latino ethnicity and discrimination interact to predict cortisol dysregulation, which implies that an appropriate model for understanding the sociocultural problem of minority health discrepancies cannot simply rely on the effects of ethnicity or discrimination alone.This research adds to the evidence that discrimination is not merely a social injustice; it is also a public health problem.