Abstract
Purpose: :
To estimate the 9-year incidence and risk factors for age-related macular degeneration (AMD) in a general Japanese population.
Methods: :
In 1998, a total of 1,775 Hisayama residents aged 40 years or older underwent a baseline eye examination. Of those, 1,401 subjects (78.9%) took part in the follow-up eye examination in 2007 and were enrolled in the present study. At both time points, the characteristics of AMD were determined by grading color fundus photographs using the Wisconsin Age-Related Maculopathy Grading System.
Results: :
The age-standardized 9-year cumulative incidence of early AMD was 10.0%, and that of late AMD was 1.4%. Men were found to have a significantly higher incidence of late AMD than women (age-adjusted odds ratio [OR], 2.97; 95% confidence interval [CI], 1.25 to 7.09). The incidence of both early and late AMD increased significantly with age. Multiple logistic regression analysis showed that age (OR, 1.10; 95% CI, 1.05 to 1.16), smoking habits (OR, 3.98; 95% CI, 1.07 to 14.7), and circulating WBC count (OR, 1.38; 95% CI, 1.07 to 1.79) were significantly associated with the development of late AMD.
Conclusions: :
Our findings suggest that the 9-year incidence of late AMD among Japanese is lower than that among white people in Western countries but higher than that among people of African descent. Smoking habits and circulating WBC count are significant risk factors for the development of late AMD in Japanese.
Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: prevalence/incidence • clinical (human) or epidemiologic studies: risk factor assessment