Abstract P236: Association Between Perceived Discrimination and Arterial Stiffness in Non-Hispanic Black Adults

Abstract

Introduction: Racial discrimination is a chronic stressor that may contribute to cardiovascular disease (CVD) disparities in non-Hispanic Black (NHB) adults. Compared to non-Hispanic White adults, NHB adults experience greater perceived discrimination (PD), chronic perceived stress (PS), and burden of CVD risk. However, associations between PD, PS, and CVD risk, measured as arterial stiffness (AS), have not been tested in a population-based study of NHB adults in the US, limiting our understanding of whether and how CVD prevention initiatives should target PD and PS. Purpose: Determine the association between PD and AS, and whether this association is modified by biological sex and mediated by PS. Hypothesis: We hypothesized a direct association between PD and AS and that associations will be stronger in females and mediated by PS. Methods: Study sample included 594 NHB adults with complete data who participated in the Jackson Heart (JHS) and Atherosclerosis Risk in Communities (ARIC) studies’ shared cohort. PD (lifetime, everyday, and burden of lifetime discrimination) and PS were measured at JHS baseline (2000-2004). AS was measured at ARIC Visit 5 (2011-2013). PD and PS were coded as continuous variables. Effect modification was evaluated by including an interaction term between sex and PD in fully adjusted models. Mediation was assessed via the natural indirect effects from the CAUSALmed procedure. Models were adjusted for age, sex, body mass index (BMI), blood pressure medication, diabetes status, and mean arterial pressure (MAP). Results: Participants had a mean [95% confidence interval (95%CI)] age of 64.7 [64.3, 65.1] years, BMI of 30.1 [29.7, 30.6] kg/m 2 ; 69% (410 of 594) were female, 24% (143 of 594) had diabetes, and 70% (416 of 594) had hypertension. Mean [95%CI] total scores for everyday, lifetime, and burden of lifetime PD were 1.96 [1.89, 2.03], 2.97 [2.81, 3.14], and 2.28 [2.21, 2.34], respectively. Mean [95%CI] AS, measured as pulse wave velocity, was 12.42 [12.15, 12.70] m/s. A 1-unit increase in lifetime PD score was associated with a decrease in AS ( β =- 0.30 [-0.57, -0.02] m/s ). The association remained after adjusting for demographics and clinical characteristics ( β= -0.29 [-0.55, 0.02] m/s ), but was no longer statistically significant when including MAP ( β= -0.21 [-0.46, 0.05] m/s ). There were non-significant associations between everyday PD and burden of lifetime PD and AS. There was no evidence of effect modification by sex or mediation by PS. Conclusion: Higher lifetime PD, but not everyday PD or burden of lifetime PD, was associated with lower AS in crude models. However, the association was attenuated to non-significance when adjusted for MAP, suggesting the association between PD and AS may be pressure-dependent. Future studies characterizing PD’s role in CVD risk development in other geographical regions and NHB populations.