The relationship between apolipoprotein E, dementia, and vascular illness

The purpose of this study was to concurrently assess the relationship of Apolipoprotein E (APOE) with both dementias and vascular illnesses in the very old. Nine hundred and fifty nine subjects (mean age 85 years) in a long-term care facility were genotyped and cognitively tested with the Mini Mental State Exam. All subjects were studied for the relationship of APOE with atherosclerotic heart disease, hypertension, or stroke without concomitant dementia. Four hundred fifty individuals met criteria for inclusion into one of the following groups: Alzheimer's disease ( n=318), vascular dementia ( n=49), or not demented controls ( n=83) and were investigated for the relationship between APOE and these diagnostic categories. APOE ϵ4 was not associated with atherosclerotic heart disease, hypertension, or stroke without concomitant dementia. The APOE ϵ3 allele was more common in men with atherosclerotic heart disease. In contrast, the APOE ϵ4 allele was more common in patients with Alzheimer's disease (22%) and vascular dementia (26%) than in not demented controls (7%). APOE ϵ4 is associated with dementias in the very old, whereas its relationship with either peripheral or central nervous system vascular disease without dementia is not as robust.