and Purpose-Leukocyte count has been associated with cardiovascular and cerebrovascular disease, including carotid plaque thickness, in several studies. We hypothesized that white blood cell count is associated with aortic arch plaque thickness (AAPT). Methods-Leukocyte count was measured in randomly selected stroke-free community participants undergoing transesophageal echocardiography. AAPT was measured for each subject and dichotomized into Ͻ4 and Ն4 mm (thick plaque). Multivariate linear

more »

... logistic regression was used to calculate the effect of leukocyte count on AAPT after adjustment for potential confounding factors. Mean age of the 145 participants was 68.5Ϯ8.3 years; 43.5% were women; 15.9% were white; 31.7% were black; and 49.0% were Hispanic. Results-Mean leukocyte count was 5.88Ϯ1.76ϫ10 9 /L. Each unit increase in leukocyte count was associated with a mean 0.28-mm increase in AAPT (Pϭ0.0036). After adjustment for other atherosclerosis risk factors, including age, sex, hypertension, diabetes, hyperlipidemia, and smoking, the relationship persisted (mean increase in AAPT, 0.24 mm; Pϭ0.0064). Thirty-five participants (24.1%) had AAPT Ն4 mm. Mean leukocyte count among those with thick plaque was significantly higher than among those with plaque Ͻ4 mm (6.54Ϯ1.60 versus 5.65Ϯ1.76ϫ10 9 /L, respectively; Pϭ0.009). Each unit increase in leukocyte count was associated with an increased risk of thick plaque (adjusted odds ratio, 1.38; 95% CI, 1.05 to 1.79). The relationships were similar for men and women and for those Ͻ70 or Ն70 years of age. Conclusions-Leukocyte count is associated with AAPT and is specifically correlated with AAPT Ն4 mm, a degree of thickening associated with increased stroke risk. These findings are consistent with current hypotheses regarding the inflammatory or infectious etiology of risk of atherosclerosis and stroke. (Stroke. 2002;33:2587-2592.)