Twenty-six–Year Change in Total Cholesterol Levels and Incident Dementia

Abstract
Although the importance of several vascular factors in the evolution of dementia and Alzheimer disease (AD) has become established over the past decade, associations with cholesterol levels remain controversial. Two studies1,2 have found associations between higher midlife total cholesterol levels and increased risk of AD 20 to 30 years later. However, 2 studies with shorter follow-up periods have found associations between lower total cholesterol levels and incident AD,3,4 and cross-sectional studies have most often found associations with lower rather than higher total cholesterol.5