A large-scale study on relationship between cerebral blood flow velocity and blood pressure in a natural population

In order to verify the relationship between blood pressure and cerebral blood flow velocity in sub-clinical natural population, 1294 middle-aged and old Beijing rural residents were investigated in autumn 2002. For all subjects, systolic blood flow velocities (V(s)) in common carotid artery (CCA), internal carotid artery (ICA) and middle cerebral artery (MCA) were detected with trans-cranial Doppler. Key factors such as anthropometry, medication use, blood pressure and blood biochemical analysis were investigated at the same time. After controlling for age, gender, diabetes, hypercholesterolaemia, smoking and body mass index, multivariate analysis showed that systolic blood pressure (SBP) correlated positively with V(s) at MCA and slight negatively correlated with at CCA. As blood pressure rose by 10 mm Hg, the V(s) at MCA increased by 1.63 cm/s. Duration of hypertension (HD) negatively correlated with V(s) at MCA (P<0.01). The V(s) at MCA in early-stage and chronic hypertensive patients were 92.9+/-1.9 and 84.1+/-2.3 cm/s, respectively. Antihypertensive treatment could modify the V(s) at MCA towards a normal level by lowering blood pressure. In conclusion, the effect of hypertension on cerebral blood flow is complex. V(s) at MCA positively correlated with SBP, but negatively related to HD. Antihypertensive treatment might be helpful to keep cerebral blood flow at a normal level.