First-generation college student status and minoritized race and ethnicity: Intersectional predictors of life stress exposure and lab-based cortisol reactivity

Theory and evidence link first-generation college students and minoritized race/ethnicity with heightened life stress exposure and potentially alterations in biological stress reactivity as adversity gets "under the skin," but more evidence and statistical tools are needed to understand how multiple minoritized identities influence health. In 171 emerging adults, we tested hypotheses that these intersecting identities increase life stress exposure, measured with the UCLA Life Stress Interview; we also probe properties of four statistical approaches to modeling intersectional identities' influence. In a subset of n = 150, growth curve modeling tested the hypothesis that more minoritized identities intensify discrimination's effect on blunted cortisol reactivity to an explicit negative evaluative variant (n = 77) versus a control variant (n = 73) of the Trier Social Stress Test. Results link both minoritized identities with elevated exposure to non-interpersonal chronic stress (t = 3.85, p < .001), and minoritized race/ethnicity with elevated interpersonal chronic stress (t = 2.743, p = .007). Of the statistical approaches examined, an identity cumulative risk score demonstrated high sensitivity, consistent with developmental research. Finally, cumulative minoritized identities moderated the relationship between self-reported discrimination and cortisol reactivity to negative evaluative lab-based stress (t = 2.12, p = 0.035), driven by a significant discrimination and cortisol blunting association in those with both minoritized identities. Taken together, we provide evidence to support modeling intersectional identities as a cumulative risk score with post-hoc tests, and evidence that first-generation student status and minoritized race/ethnicity cumulatively heighten stress exposure and intensify the effect of discrimination on a maladaptive marker of stress-responding.