Mediators of the Relationship Between Race and Allostatic Load in African and White Americans

Objective: Allostatic load (AL) is a cumulative index of physiological dysregulation, which has been shown to predict cardiovascular events and all-cause mortality. On average, African Americans (AA) have higher AL than their White American (WA) counterparts. This study investigated whether differences in discrimination, negative affect-related variables (e.g., experience and expression of anger, depression), and health practices (e.g., exercise, alcohol use, smoking, subjective sleep quality) mediate racial differences in AL. Method: Participants included healthy, AA (n = 76) and WA (n = 100), middle-aged (M-age = 35.2 years) men (n = 98) and women (n = 78). Questionnaires assessed demographics, psychosocial variables, and health practices. Biological data were collected as part of an overnight hospital stay-AL score was composed of 11 biomarkers. The covariates age, gender, and socioeconomic status were held constant in each analysis. Results: Findings showed significant racial differences in AL, such that AA had higher AL than their WA counterparts. Results of serial mediation indicated a pathway whereby racial group was associated with discrimination, which was then associated with increased experience of anger and decreased subjective sleep quality, which were associated with AL (e.g., race -> discrimination -> experience of anger -> subjective sleep quality -> AL); in combination, these variables fully mediated the relationship between race and AL (p < .05). Conclusion: These results suggest that discrimination plays an important role in explaining racial differences in an important indictor of early disease through its relationship with negative affect-related factors and health practices.