Commentary on “Developing a national strategy to prevent dementia: Leon Thal Symposium 2009.” Is dementia among older individuals 75+ a unique disease?

We have failed to identify a preventable determinant of older age dementia(s), ie 70-751, in spite of many years of research. We have, as noted in this report from the 2009 Leon Thal Symposium, been very successful in developing in vivo measurements of the pathophysiology of dementia, including magnetic resonance imaging (MRI) and positron emission tomography (PET) scan, etc, and identification of genetic attributes. Prospective risk predictors based on combinations of cognitive testing, brain MRI and PET scanning, genetics, apolipoprotein E 34 (APOE 34), and likely cerebrospinal fluid (CSF) analysis are as good at predicting short-term risk of dementia as risk factors for coronary heart disease (CHD). This new information, unfortunately, will not result in prevention of dementia. [1,2] The primary prevention of a disease such as dementia usually requires the identification of specific etiologies, ie lifestyles, environmental exposures, and host susceptibilitygenetics. The etiological agents are often found by observing large variations in disease incidence or mortality among populations, for example, the relationship of dietary saturated fat and cholesterol intake, blood cholesterol levels and geographic variations in CHD, and/or marked changes in temporal trends of a disease, such as the association of cigarette smoking and lung cancer. Unique high-risk families—in which both the genetics and phenotypes have been determined, such as in familial hyperlipidemia or familial earlyage Alzheimer’s disease (AD) —can also provide important leads to etiology. Longitudinal, epidemiological studies (ie the Framingham Heart Study) evaluate the risk factors and