Contradictions cloud our understanding of the role of cholesterol in the development of clinical dementia, including Alzheimer Disease (AD). Some studies suggest that high blood cholesterol levels in midlife increase the risk for AD, while others show that low levels late in life are associated with AD. Both weight loss and decreased blood pressure generally arises before the onset of AD. Thus, it has been predicted that a drop in cholesterol would also precede dementia.

The Honolulu-Asian Aging study, in which over 3700 Japanese-American men were followed for a total of 29 years, provided an opportunity to determine the effect of cholesterol on clinical dementia. Clinicians and scientists led by Lenore Launer, Ph.D. (NIH) published the results of their study in the January 6, 2007 issue of the Archives of Neurology. In this study, cholesterol levels of 1027 men born between 1900-1919 on the island of Oahu, HI were measured at five different times: between 1965-1968, twice during 1970-1974, 1980-1982, and 1991-1993. The men were initially evaluated between 1991-1993, and then followed annually through 1996, for the development of dementia... Read More