RESUMEN
Objectives: Amyloid-ß (Aß) deposition in the brain is the hallmark of Alzheimer's disease (AD) pathology. Hypertension is a risk factor for AD, but the effects of hypertension on Aß deposition are not fully determined. Considering peripheral Aß closely relates to Aß deposition in the brain, we investigated the relationships between blood pressure (BP) level and plasma Aß concentrations. Methods: One-thousand and sixty-nine participants (age above 45) from a village in the suburbs of Xi'an, China were enrolled. Questionnaires and validated Chinese versions of the Mini-Mental State Examination (MMSE) were used to collect information about vascular risk factors and assess cognition function. The apolipoprotein E (ApoE) genotype was detected using PCR and sequencing. Plasma Aß levels were measured using ELISA. The associations between BP and plasma Aß levels were analyzed by using multivariate linear regression. Results: Plasma Aß1-40 level was higher in high BP group than that in normal BP group (53.34 ± 8.50 pg/ml vs. 51.98 ± 8.96 pg/ml, P = 0.013), in high SBP group than that in normal SBP group (53.68 ± 8.69 pg/ml vs. 51.88 ± 8.80 pg/ml, P = 0.001) and in high MABP group than that in normal MABP group (54.05 ± 8.78 pg/ml vs. 52.04 ± 8.75 pg/ml, P = 0.001). After controlling for the confounding factors, SBP (b = 0.078, P < 0.001), DBP (b = 0.090, P = 0.008) and MABP (b = 0.104, P < 0.001) correlated with plasma Aß1-40 level positively in ApoE ε4 non-carriers, but not ApoE ε4 carriers. Conclusions: Elevated BP levels were associated with increased plasma Aß1-40 levels in middle-aged and elderly ApoE ε4 non-carriers.