Abstract 13729: Subclavian Artery, Thoracic Aorta, and Coronary Artery Calcification, Age, Race/Ethnicity and Sex Distributions: The Multi-Ethnic Study of Atherosclerosis

Abstract

Introduction: Upper extremity atherosclerosis is typically localized in the subclavian arteries, although it is less prevalent and less often symptomatic than in the lower extremities. Subclavian artery calcification (SAC) is a metabolic consequence of subclavian artery atherosclerosis. Hypothesis: SAC is different in gender and in different ethnicties. Aim: We studied SAC, in comparison with coronary artery calcification (CAC) and descending thoracic aorta calcification (TAC) in the MESA study population. Methods: We quantified SAC, TAC, and CAC in MESA participants who had a chest CT in 2016-18 (N = 2756, mean age 68.3±9.2 years, 48% male, 27% Black, 13% Chinese, 22% Hispanic, 38% White). We characterized the distributions of SAC and TAC, relative to CAC, and examined their associations with age, race/ethnicity, and sex. Race and sex differences were studied separately using logistic regression, adjusted for age, for each vascular bed. Results: Prevalence of any SAC was 62%, TAC 60%, and CAC 69%. Among those with any calcification, N, median and 90th percentiles were SAC: 1704, 76, 534; TAC: 1655, 152, 2011; CAC 1896, 135, 1118. Pairwise correlations [ln(Agatston score + 1)] were SAC - TAC: 0.61, SAC - CAC: 0.48, TAC - CAC: 0.48. Correlations with age were 0.46 for SAC, 0.58 for TAC and 0.40 for CAC. SAC and TAC prevalences were similar for males and females, but CAC was more common in males (Table, p<0.05 for each race/ethnic group). Differences in prevalence varied by race, with small race differences for SAC, Chinese highest for TAC, and CAC highest for White (Table, groups with the same superscript within row do not differ significantly). Conclusion: In older adults, SAC and TAC occur almost as commonly as CAC. Calcification is moderately correlated between beds. The racial distribution is different for CAC than for SAC or TAC.