Prevalence of age-related maculopathy in the adult population in China: The Beijing eye study

OBJECTIVE: To evaluate the prevalence of age-related maculopathy (ARM) in adult Chinese living in rural or urban regions of mainland China. DESIGN: Population-based prevalence study. METHODS: The study included 4439 subjects (aged 40 or more years) out of 5324 subjects invited to participate (response rate 83.4%). It was held in rural and urban regions of Greater Beijing. The participants underwent a detailed ophthalmic examination including fundus photography. All fundus photographs were graded by the Wisconsin Age,Related Maculopathy Grading System. RESULTS: Fundus photographs were available for 4376 (98.6%) subjects. Early ARM was present in 122 (1.4%) of 8655 (95% confidence interval [CI] 1.16% to 1.66%) eyes or 63 (1.4%) of 4376 (95% CI 1.09% to 1.79%) subjects, late ARM in 12 (0-14%) of 8655 (95% CI 0.06% to 0.22%) eyes or seven (0.2%) of 4376 (95% CI 0.04% to 0.28%) subjects, and exudative ARM as part of late ARM in seven (0.1%) of 8655 (95% CI 0.02% to 0.14%) eyes or six (0.1%) of 4376 (95% CI 0.03% to 0.25%) subjects. The prevalence of early ARM, late ARM, and exudative ARM, respectively, increased from 0.61%, 0.07%, and 0.07% in the 40-to-44-year age group, to 1.66%, 0.26%, and 0.26% in the 55,to 59-year group, and to 2.99%, 0.90%, and 0.60% in the group aged 75 years and older. ARM was causative for visual impairment (best-corrected visual acuity in the better eye, < 20/60 and >= 20/400) or blindness (visual acuity < 20/400) in one subject (0.023%). CONCLUSIONS: Visual impairment due to ARM was relatively uncommon in the adult Chinese population in rural and urban regions.