Association between absolute blood eosinophil count and carotid plaque and coronary artery calcification in the Multi-Ethnic Study of Atherosclerosis (MESA)

Prior studies have demonstrated associations between eosinophil activation products and incident stroke. We investigated whether circulating eosinophil concentration is associated with imaging markers of atherosclerotic cardiovascular disease (ASCVD), analyzing 2 arterial beds (carotid artery plaque [CAP] and coronary artery calcium [CAC]) in the Multi-Ethnic Study of Atherosclerosis (MESA). The MESA enrolled individuals aged 45 to 84, without ASCVD at baseline. ASCVD risk factors, blood eosinophils, CAP presence/score (0 to 12), and CAC presence/Agatston score were measured at MESA Exam No. 5. Using logistic and linear regression analyses, the relationships between blood eosinophils, CAP or CAC presence, or scores (log[score + 1]), adjusted for confounders, were evaluated. The 2,166 participants were a mean (standard deviation [SD]) 69.6 (9.3) years old, 53% female, 29% Hispanic, 28% Black, 1% Chinese American. The eosinophil count was median (interquartile range) 0.10 (0.10, 0.20)×103/μl, CAP score 2 (0, 4), and CAC score 45 (0, 292) Agatston units. In risk-factor adjusted models, increased blood eosinophil count (per 1 SD [0.15 × 103/μl]) was associated with log scores of CAP (β: 0.05 [95% confidence interval 0.02 to 0.08, P = 0.001) or CAC (β: 0.11, [0.01 to 0.21], P = 0.03). Similar associations were observed for eosinophils and CAP (odds ratio [OR]: 1.12, [1.01 to 1.25], P = 0.03) and CAC (OR: 1.15, [1.02 to 1.30], P = 0.02) presence. In conclusion, in a large, multiethnic US cohort, blood eosinophils were independently linked to imaging atherosclerosis measures in 2 arterial distributions. These data suggest potential roles of eosinophilic inflammation in atherosclerosis.