Race Differences in High-Grade Carotid Artery Stenosis

Background and Purpose: Despite a higher incidence of stroke and a more adverse cardiovascular risk factor profile in Blacks and Hispanics compared with Whites, carotid artery revascularization is performed less frequently among these subpopulations. We assessed racial differences in high-grade (≥70% diameter-reducing) carotid stenosis. Methods: Consecutive clients in a Nationwide Life Line for-Profit Service to screen for vascular disease, 2005 to 2019 were evaluated in a cross-sectional study. The prevalence of high-grade stenosis, defined by a carotid ultrasound peak systolic velocity of ≥230 cm/s, was assessed. Participants self-identified as White, Black, Hispanic, Asian, Native American, or other. Race/ethnic differences were assessed using Poisson regression. The number of individuals in the United States with high-grade stenosis was estimated by applying prevalence estimates to 2015 US Census population estimates. Results: The prevalence of high-grade carotid stenosis was estimated in 6 130 481 individuals. The prevalence of high-grade stenosis was higher with increasing age in all race-sex strata. Generally, Blacks and Hispanics had a lower prevalence of high-grade stenosis compared with Whites, while Native Americans had a higher prevalence. For example, for men aged 55 to 65, the relative risk of stenosis compared with Whites was 0.40 (95% CI, 0.29–0.55) and 0.61 (95% CI, 0.46–0.81) for Blacks and Hispanics, respectively; and 1.53 (95% CI, 1.12–2.10) for Native Americans. When these prevalence estimates were applied to the Census estimates of the US population, an estimated 327 721 individuals have high-grade stenosis, of whom 7% are Black, 7% Hispanic, and 43% women. Conclusions: Despite their having a more adverse cardiovascular risk profile, there was a lower prevalence of high-grade carotid artery stenosis for both the Black and Hispanic relative to the White clients. This lower prevalence of high-grade stenosis is a potential contributor to the lower use of carotid revascularization procedures in these minority populations.