This paper focuses on the review of risk factors of Alzheimer's diseas
e (AD). Despite the vast literature on AD only advanced age and geneti
c predisposition have been known factors in the development of this di
sease. Recent data estimate a point prevalence of 3% in the age group
from 65 - 69 and a steady increase to 24% after the age of 85 and olde
r. The allele ApoE4 on chromosome 19 is liked to the sporadic form of
AD with late onset, although not disease specific. The risk factor is
increasing from 20 to 90% with the growing number of ApoE4-allele. Sin
ce the sporadic form of AD is diagnosed much more frequently and about
40% of the cases are ApoE4-negative, one should not overestimate the
percentage of AD in patients with a genetic component. No gender diffe
rences have been established in view of education, social factors and
higher life expectancy of women. Mental and physical activities seem t
o improve coping strategies and develop reserve capacities. The lack o
f education presents a risk factor as opposed to at least 6 years of e
lementary schooling. Various studies report an association of AD with
head injuries. Depression, which is diagnosed 3 times more often prior
to the onset of AD, may be part of a prodromal stage preceding the ac
tual symptoms by several years. Thus, conclusions should be drawn with
caution. No increased risk with nicotine and alcohol has been found.
However, maternal age, exposure to aluminum, estrogen deficiency and v
arious diseases have been controversially discused.