Synergistic effects of traumatic head injury and apolipoprotein-epsilon 4 in patients with Alzheimer's disease.
The apolipoprotein-epsilon 4 allele increases the risk of Alzheimer's disease (AD), but cerebral deposition of beta-amyloid with age, a genetic mutation, or head injury may contribute to the pathogenesis of this disease. We examined the risks of AD associated with traumatic head injury and apolipoprotein-epsilon 4 in 236 community-dwelling elderly persons. A 10-fold increase in the risk of AD was associated with both apolipoprotein-epsilon 4 and a history of traumatic head injury, compared with a two-fold increase in risk with apolipoprotein-epsilon 4 alone. Head injury in the absence of an apolipoprotein-epsilon 4 allele did not increase risk. These data imply that the biological effects of head injury may increase the risk of AD, but only through a synergistic relationship with apolipoprotein-epsilon 4.
Mayeux
R
R
Gertrude H. Sergievsky Center, Columbia University, New York, NY 10032.
Ottman
R
R
Maestre
G
G
Ngai
C
C
Tang
M X
MX
Ginsberg
H
H
Chun
M
M
Tycko
B
B
Shelanski
M
M
D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D000544:Alzheimer Disease / Q000209:etiology* / Q000235:genetics*; D053327:Apolipoprotein E4; D001057:Apolipoproteins E / Q000235:genetics*; D001930:Brain Injuries / Q000150:complications*; D004247:DNA / Q000032:analysis; D005260:Female; D005819:Genetic Markers; D006801:Humans; D008297:Male; D012307:Risk Factors
D053327:Apolipoprotein E4; D001057:Apolipoproteins E; D005819:Genetic Markers; D004247:DNA