15
direct comparisons between African-Americans and
Caucasians. Statistical power was generally low for these
comparisons, but these studies globally suggest that
the prevalence of late AMD is at least 2-fold lower in
African-Americans. In the Barbados Eye Study, bearing
on subjects of African origin from the Barbados Island,
the prevalence rate of late AMD (0.57%) was similar
to those observed in African-Americans (Table 3)
(7)
.
Therefore, people of African origin appear to be at much
lower risk of late AMD than Caucasians, although no
data are available from African countries. American
Hispanics also appear to be at lower risk for late AMD
Epidemiology of AMD
than Caucasian, with prevalence rates ranging from
0.09% to 0.5% among studies (Table 2). The reasons
for the lower prevalence rates in African-American and
Hispanics are unclear. No data are available on minori-
ties of other industrialized countries, in particular in
Europe. This constitutes a limitation to the estimation
of the prevalence of AMD in European countries, which
Figure 1. Prevalence of late AMD according to age and gender in Caucasians from industrialized countries (adapted from the meta-analysis by
Friedman et al.
(3)
)
0
2
4
6
8
10
12
14
16
18
50-54 55-59 60-64 65-69 70-74 75-79 80+
Age (years)
Prevalence (%)
Men
Women
have different types of ethnic groups than in the United
States (populations originating from North Africa,
Middle-east countries, India…). Given the major dif-
ferences observed in ethnic groups in the United States,
such epidemiological data in European minorities are
warranted.
Other epidemiological studies have mainly been con-
ducted in Asia (Japan, India and China). In contrast
to what was originally thought, late AMD is not rare
in these Asian populations, as shown in Table 3. In two
Japanese studies
(8,9)
, the prevalence rates in Japanese men
were similar to those observed in Caucasian men from
industrialized countries, while late AMD appeared rare
in Japanese women. This gender-effect, which is not
observed in industrialized countries, may be due to gen-
der-related smoking habits in Japanese. Indeed, smoking
is a major risk factor for AMD, in all studied popula-
tions. In these two studies, smoking was very frequent in
Japanese men, while rare in Japanese women.
