Discrimination and Cardiovascular Health in Black Americans: Exploring Inflammation as a Mechanism and Perceived Control as a Protective Factor

Abstract

Objective: Inflammation may be an integral physiological mechanism through which discrimination impacts cardiovascular health and contributes to racial health disparities. Limited research has examined psychosocial factors that protect against the negative effects of discrimination on inflammation. Perceived control is a promising possible protective factor, given that it has been shown to moderate the relationship between other psychosocial stressors and physiological outcomes. This study thus tested whether systemic inflammation mediated the link between discrimination and cardiovascular health and whether perceived control moderated this relationship.

Methods: Data for this project included 347 non-Hispanic/Latinx Black adults (mean [standard deviation] age = 51.64 [11.24] years; 33% female) taken from the Midlife in the United States study. Perceived control and daily discrimination were assessed via self-report, and inflammation was measured via circulating levels of C-reactive protein (CRP), interleukin-6 (IL-6), fibrinogen, and tumor necrosis factor α. Cardiovascular health was measured by morbidity of cardiovascular conditions: heart disease, hypertension, and/or stroke.

Results: CRP (indirect effect: b = 0.004, 95% confidence interval [CI] = 0.001-0.007) and fibrinogen (indirect effect: b = 0.002, 95% CI = 0.0003-0.005) mediated the link between discrimination and cardiovascular conditions. Perceived control moderated the relationship between discrimination and CRP ( F (1, 293) = 4.58, Δ R2 = 0.013, b = -0.02, SE = 0.01, p = .033). CRP mediated the link between discrimination and cardiovascular conditions only for those who reported low levels of perceived control (Index = -0.003, 95% CI = -0.007 to -0.0001).

Conclusion: Findings provide empirical evidence of inflammation as a mechanism linking discrimination to cardiovascular conditions among Black Americans. Additionally, perceived control may be protective. Findings could suggest beliefs about control as a potential intervention target to help reduce the negative effects of discrimination on cardiovascular health among Black Americans.

Figure 1.. Models depicting hypothesized relationships between discrimination, inflammation, perceived control, and cardiovascular outcomes.

Note. Panel A depicts the proposed mediation pathway via inflammation. Panel B depicts the moderating relationship and Panel C models the proposed moderated mediation linking discrimination to cardiovascular conditions through inflammation, but dependent upon perceived control.

Figure 2.. Models depicting mediation, moderation, and moderated mediation results for discrimination, perceived control (composite), CRP, and cardiovascular conditions.

Note. Panel A models the indirect effect of discrimination on cardiovascular conditions through CRP. Panel B models the moderation effect of perceived control in the relationship between discrimination and CRP. Panel C models the conditional indirect effect of discrimination on cardiovascular conditions through CRP based on level of perceived control (i.e., low, average, and high). *** p < .001, ** p< .01, * p < .05.