RESUMEN
BACKGROUND: Growing evidence indicated that to develop of atherosclerosis observed more often by people with Alzheimer's disease (AD), but the underlying mechanism is not fully clarified. Considering that amyloid-ß (Aß) deposition in the brain is the key pathophysiology of AD and plasma Aß is closely relate to Aß deposition in the brain, in the present study, we investigated the relationships between atherosclerosis and plasma Aß levels. METHODS: This was a population based cross-sectional study. Patients with high risk of atherosclerosis from Qubao Village, Xi'an were underwent carotid ultrasound for assessment of atherosclerosis. Venous blood was collected on empty stomach in the morning and plasma Aß1-40 and Aß1-42 levels were measured using ELISA. Multivariate logistic regression analysis was performed to investigate the relationships between carotid atherosclerosis (CAS) and plasma Aß levels. RESULTS: Among 344 patients with high risk of atherosclerosis, 251(73.0%) had CAS. In the univariate analysis, the plasma Aß levels had no significant differences between CAS group and non-CAS group (Aß1-40: 53.07 ± 9.24 pg/ml vs. 51.67 ± 9.11pg/ml, p = 0.211; Aß1-42: 40.10 ± 5.57 pg/ml vs. 40.70 pg/ml ± 6.37pg/ml, p = 0.285). Multivariate logistic analysis showed that plasma Aß levels were not associated with CAS (Aß1-40: OR = 1.019, 95%CI: 0.985-1.054, p = 0.270;Aß1-42: OR = 1.028, 95%CI: 0.980-1.079, p = 0.256) in the total study population. After stratified by hypertension, CAS was associated with plasma Aß1-40 positively (OR = 1.063, 95%CI: 1.007-1.122, p = 0.028) in the non-hypertension group, but not in hypertensive group. When the plasma Aß concentrations were classified into four groups according to its quartile, the highest level of plasma Aß1-40 group was associated with CAS significantly (OR = 4.465, 95%CI: 1.024-19.474, p = 0.046). CONCLUSION: Among patients with high risk of atherosclerosis, CAS was associated with higher plasma Aß1-40 level in non-hypertension group, but not in hypertension group. These indicated that atherosclerosis is associated with plasma Aß level, but the relationship may be confounded by hypertension.