Racial Disparities in Arterial Stiffness Between Healthy Whites and African Americans in the United States: A Meta-analysis.

BACKGROUND: African Americans (AAs) present with cardiovascular disease (CVD) risk factors at younger ages than whites. Consequently, CVD and stroke occur at a higher incidence and at earlier decades in life in AA populations. Arterial stiffness is a predictor of CVD outcomes and partially explains the CVD risk experienced by racial minorities. We evaluated the differences in arterial stiffness observed in AAs and whites through a systematic review and meta-analysis. METHODS: We searched PubMed and SCOPUS for comparative studies published March 1995 to November 29, 2017 comparing arterial stiffness assessments (pulse wave velocity, augmentation index, and central blood pressure) between AAs and whites. Two independent reviewers examined 195 titles/abstracts, 85 full text articles and 11 articles were included in the meta-analysis using random effects modeling approaches. MAIN RESULTS: A total of 5060 white and 3225 AAs were included across 11 relevant studies. Carotid-femoral pulse wave velocity (cfPWV) measures were statistically different between AAs and whites (mean difference = -0.44, 95% confidence interval [CI]: -[-0.67, -0.21], p = 0.0002). Aortic femoral pulse wave velocity was significantly different between AAs and whites (mean difference = -0.21, [95% CI] -0.35, -0.07, p = 0.003) regardless of sex. Augmentation index (AIx) and Augmentation index at a 75 beats per minutes heart rate (AIx @75) was also significantly different between AA and whites (mean difference = -4.36 [95% CI] = -6.59, -2,12, p = 0.0001 and -6.26, [95% CI] = -9.19, -3.33, p < 0.0001, respectively). CONCLUSIONS: Racial disparities in arterial stiffness persist among African American racial groups in the United States. The lack of homogeneity in studies capturing racial disparities in cfPWV suggest that additional studies are needed to understand the magnitude of racial differences in African Americans and whites that might be clinically relevant.