Prevalence and characteristics of age-related macular degeneration in the Japanese population: the Nagahama study.
OBJECTIVE
To estimate the age- and sex-specific prevalence of early age-related macular degeneration (AMD; drusen and retinal pigment abnormalities) and late AMD (exudative AMD and geographic atrophy) in the Japanese population.


METHODS
Community-based, cross-sectional study.


METHODS
The study was held in Nagahama, Japan, and included 6065 Japanese individuals (aged ≥50 years) recruited in 2008-2010. We graded fundus photographs of both eyes for the AMD phenotype based on drusen size, the presence of retinal pigment abnormalities, and late AMD. The associations between smoking and AMD phenotypes were also evaluated.


RESULTS
We assessed 5595 subjects (women, 65%) with a gradable macular condition. Early and late AMD prevalence increased from 16.1% and 0.27% at 50-59 years to 31.2% and 0.98%, respectively, at 70-74 years and was predominant in male subjects in each age group. Smoking was associated with both early and late AMD stages and retinal pigment abnormalities (P < .0001), but not with drusen (P = .305). The prevalence of retinal pigment abnormalities was significantly higher in men (P < .0001), which was associated with high rates of cigarette smoking. We found no sex difference for the prevalence of large drusen (P = .264).


CONCLUSIONS
The prevalence of early AMD among adult Japanese persons was similar to the rates in white populations. The prevalence of late AMD in Japanese people aged <70 years was similar to that observed in white populations, whereas that in Japanese people aged ≥70 years was relatively lower.
Department of Ophthalmology, Kyoto University Graduate School of Medicine, Kyoto, Japan; Center for Genomic Medicine/Inserm U.852, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Isao
I
Nakata
Kenji
K
Yamashiro
Hideo
H
Nakanishi
Yumiko
Y
Akagi-Kurashige
Masahiro
M
Miyake
Akitaka
A
Tsujikawa
Fumihiko
F
Matsuda
Nagahisa
N
Yoshimura
D017677:Age Distribution; D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008268:Macular Degeneration / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D015995:Prevalence; D011446:Prospective Studies; D017678:Sex Distribution; D012907:Smoking / Q000453:epidemiology; D011795:Surveys and Questionnaires