A consistent amount of evidence suggests that vascular factors might be involved in the pathogenesis of late onset Alzheimer's disease (LOAD). We evaluated the presence of endothelial dysfunction by measuring the plasma levels of soluble E-selectin and vascular cell adhesion molecule 1 (VCAM-1) in a sample of patients affected by LOAD (n. 60) or vascular dementia (VD: n. 80). They were compared with a sample of older patients with cerebrovascular disease but not-dementia (CDND: n. 40), and with a sample of healthy older controls (n. 30). sVCAM-1 plasma levels were higher in LOAD and VD compared with controls. Among patients (LOAD, VD, and CDND), sE-selectin levels were higher in individuals with most severe cerebrovascular disease on CT scan. At multivariate regression analysis, fasting glucose (p<0.05) and TNF-alpha levels (p<0.02) were positively correlated with sE-selectin levels (adjusted r(2): 20%), while sVCAM-1 was positively correlated with age (p<0.01), and alcohol consumption (p: 0.03), and negatively associated with HDL-C levels (p: 0.005), (p<0.01; adjusted r(2): 44%), independent of possible confounders. Increased sVCAM-1 plasma levels in LOAD and VD suggest the existence of endothelial dysfunction in both types of dementia. The possible role of E-selectin in the pathogenesis of cerebrovascular disease is also supported by our data.