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W Relationship Between Brain Atrophy Estimated by a Longitudinal Computed Tomography Study and Blood Pressure Control in Patients With Essential Hypertension

cause and treatment of senile dementia have become important issues. Because the severity of dementia is correlated with dilatation of the lateral ventricles of the brain,1,2 it is important to evaluate the degree of brain atrophy. Essential hypertension is a risk factor for brain atrophy,3,4 so the control of blood pressure is considered important in elderly patients with hypertension. Meta-analysis of published studies on the treatment of hypertension has shown that the control of hypertension in the elderly reduces the mortality rate. 5,6 However, the lower end of the autoregulation curve of cerebral blood flow in hypertensive patients was shifted to the right as compared with that of normotensive subjects. It has been suggested that an excessive reduction in blood pressure reduces the cerebral blood flow and increases the risk of cerebrovascular disorders.7–9 In the final stage of age-related brain atrophy, the reduction in cerebral blood flow is considered to correspond with the age-related loss of brain substance, a decrease in cerebral metabolism, and an adaptation to