Abstract
Previous research has found that experiences of discrimination may exact a biological toll on individuals (Lim et al., 2022; McEwen & Gianaros, 2010). Yet, to date, research on discrimination may have missed opportunities to better align itself with the weathering hypothesis (Geronimus, 2023), which emphasizes the role of sustained, chronic, and pervasive experiences of discrimination in driving poorer health outcomes over time among marginalized groups. Current approaches to quantifying discrimination experiences may not be fully capturing several critical elements of ongoing discrimination including the stability, pervasiveness, and chronicity of these experiences over time. Furthermore, few studies have considered the longer-term implications of ongoing experiences of discrimination during critical developmental periods such as the college years, especially among underrepresented students attending elite predominantly White institutions (PWIs). These discrimination experiences may be formative as students navigate struggles with identity and belonging and may exert a negative long-term effect on their aging processes. To this end, the current dissertation investigated longitudinal associations between experiences of discrimination during college among underrepresented college students and subsequent indicators of advanced aging (i.e., allostatic load and epigenetic age in young adulthood). The current study included repeated measurement of experiences of discrimination across the college years which facilitated an increased focus on ongoing experiences of discrimination (aligned with the weathering hypothesis). Moreover, repeated measurement allowed for the analysis of stability in experiences over time and potential associations of trajectories of experiences with indicators of aging. Furthermore, in this dissertation, novel approaches were introduced to scoring an established measure of discrimination, specifically in regard to the breadth of experiences (i.e., dichotomizing based on whether or not a type of mistreatment was experienced) and the chronicity of experiences (i.e., dichotomizing based on acute vs. chronic experiences of discrimination) which were then summed within waves and across waves in the spirit of better operationalizing pervasiveness and chronicity of discriminatory experiences in a cumulative manner in the college years. The current study utilized data from a pre-existing longitudinal study of underrepresented college students (N=340) attending a public, predominantly White institution (PWI) who were surveyed during the spring semesters of their first, second, third, and fourth years of college. The outcomes of interest (i.e., allostatic load, epigenetic age) were measured six years later when participants were young adults. In this dissertation, a longitudinal latent profile analysis of discrimination experiences throughout college was conducted, tracking trajectories in experiences of discrimination over time and their association with subsequent indicators of biological wear and tear. Additionally, novel approaches to scoring an established measure of everyday discrimination were tested to better capture the pervasive and chronic nature of marginalization across the four years of college through a series of regression models. Results from the longitudinal latent profile analysis indicated stability of experience of discrimination across the college years, with student experiences falling into stable lower, medium-lower, medium-higher, and higher discrimination groups (profiles demonstrated little fluctuations over time). Accordingly, profiles did not yield additional information beyond the other aggregate variables and were not utilized further in analyses. Results from regression analyses indicated that discrimination during the college years was not associated with allostatic load or epigenetic age. No direct associations were found between any of the various approaches to operationalizing discrimination and either outcome (allostatic load or epigenetic age). Finally, in the absence of finding any direct associations between any of the configurations of discrimination experiences and allostatic load or epigenetic age, post-hoc analyses were conducted to test for indirect associations between discrimination and allostatic load and epigenetic age via loneliness, self-worth, and marginalization-related vigilance. Though the aggregate discrimination variable predicted loneliness, self-worth, and marginalization-related vigilance; the only significant indirect path that emerged was from discrimination to epigenetic age via marginalization-related vigilance. These findings suggest that everyday experiences of discrimination may contribute to epigenetic aging through their impact on marginalization-related vigilance, a psychological response to ongoing marginalization. Overall, findings from this dissertation study yielded relatively little support for the hypotheses. Potential limitations of this study are discussed that could be remedied in future research as well as other directions for future research to continue to investigate potential long-term impacts of discrimination on biological wear and tear in marginalized groups, with a focus on mechanistic factors.
