Ta. Treves et al., APOE-EPSILON-4 IN PATIENTS WITH ALZHEIMER-DISEASE AND VASCULAR DEMENTIA, Alzheimer disease and associated disorders, 10(4), 1996, pp. 189-191
The apolipoprotein E (APOE) epsilon 4 allele has been consistently fou
nd to be frequent in patients with progressive degenerative dementia o
f the Alzheimer type (DAT). Vascular dementia (VD) may occur as stroke
s superimposed on presymptomatic DAT, in which case APOE-epsilon 4 fre
quency should also be increased in VD. We have examined the distributi
on of APOE-epsilon 4 in patients with DAT (n = 176) or VD (n = 74) and
controls (n = 133), and evaluated the risk of dementia associated wit
h APOE-epsilon 4. APOE-epsilon 4 allele frequency was 27% in DAT patie
nts, 21% in VD patients, and 11% in controls. The difference in the di
stribution of the epsilon 4 allele between DAT or VD patients and cont
rols was statistically significant (chi(2) test, p < 0.05), with a 3.6
- and 2.1-fold risk of dementia in DAT and VD patients carrying an eps
ilon 4 allele. The result that the APOE-epsilon 4 allele is more frequ
ent in DAT patients than in controls, with VD patients falling in betw
een, is consistent with the assumption that VD is a heterogeneous cond
ition, with some patients having an underlying preclinical brain degen
eration, in whom the dementia was precipitated by strokes.