[Hypertension as a risk factor of dementia and cognitive decline in the elderly].

Management of dementia and cognitive decline is a major issue in geriatrics. Since the average age of society is advancing and patients of dementia are increasing, it is important to remove risk factors of dementia and cognitive decline in order to maintain quality of life in the elderly and to save cost of medicine and care. While hypertension has been known to be a risk factor of cerebrovascular events and vascular dementia, recent studies show that midlife hypertension is also a risk factor of cognitive decline and Alzheimer's disease in late life. Clinical trials and retrospective observation studies also show that treatment of hypertension decreases the risk of Alzheimer's disease. These issues are also related with the consideration of vascular factors in Alzheimer's disease. The white matter lesion as a consequence of hypertension and its meaning in Alzheimer's disease are also discussed.