Less Atherosclerosis and Lower Blood Pressure for a Meaningful Life Perspective With More Brain

Abstract

Traditional teaching subdivides the dementia syndrome into neurodegenerative Alzheimer’s disease (AD), vascular dementia (VaD), and mixed variants. In spite of the vast and continuing literature on the dichotomy between AD and VaD, new emerging concepts highlight the role of cardiovascular risk factors in the pathogenesis of AD, especially in older patients.1,2 Hypertension is the major player in the pathogenesis of stroke, poststroke dementia, and VaD. AD is the most common cause of dementia, contributing from 45% to >75% of the cases in Asians and whites, respectively.3 This review will focus on the role of hypertension as a reversible risk factor in the development of dementia, in particular AD. To set the stage, we will first summarize current insights in the epidemiology of AD, the pathogenesis of VaD and AD, and the association between neurodegeneration and atherosclerosis. Across 36 cross-sectional studies, the prevalence of dementia increased exponentially from 0.3% to 1.0% in subjects aged 60 to 64 years to 10% to 20% in octogenarians and to >40% in the ninth decade of life.3 In 15 longitudinal studies, the incidence of dementia showed a similar age-related dependency with rates expressed in new cases per 1000 person-years ranging from 0.4 to 4 at 60 to 64 years to 20 to >40 at 80 to 85 years.3 Currently, 24.3 million people have dementia with an annual worldwide incidence of 4.6 million new cases.4 Because of the aging of populations, the number of demented patients will increase 2-fold every 20 years to 81.1 million by 2040, with >60% living in developing countries.4 The 2003 World Health Report5 estimated that adults aged ≥60 years lost ≈8.6 million disability-adjusted life years because of AD or other dementias. In this age group, only ischemic heart disease (31.5), cerebrovascular disease (29.6), and …