[Prevalence of low vision and blindness in defined populations in rural and urban areas in Beijing].
OBJECTIVE
To investigate the prevalence and causes of low vision and blindness in Beijing residents aged 40 and over.


METHODS
4,451 residents aged 40 and over in 3 rural communities and 5 urban communities in Beijing underwent eye examination, including examination of distant and near visual acuity (VA), best corrected distant and near VA, pinhole VA, and visual field, slit lamp biomicroscopy, and dilated ocular examination in the form of in-home survey by defined population-based sampling. The medical history was surveyed too. The data were analyzed based on the criteria of the World Health Organization.


RESULTS
The general prevalence rates of low vision and blindness were 0.99% (95% CI: 0.70-1.28) and 0.39% (95% CI: 0.21-0.57) respectively. The prevalence rate of low vision in females was 1.45%, 2.23 times that of males (0.65%) (OR: 1.97, 95% CI: 1.00-3.95). The prevalence rate of low vision of rural residents was 1.76%, 2.89 times that of urban residents (0.61%) (OR: 2.93, 95% CI: 1.43-6.11). The prevalence rate of blindness in females was 0.64% and 0.37% in males. The prevalence rate of blindness of rural residents was 1.06%, 2.04 times that of the urban residents (0.52%) (OR: 3.77, 95% CI: 1.41-10.62). The 3 major causes of blindness were cataract (37.50%), glaucoma (29.20%), and high myopic macular degeneration (8.30%). The prevalence of blindness increased with age.


CONCLUSIONS
The prevalence rates of low vision and blindness are higher in the rural areas. Cataract, glaucoma, and high myopic macular degeneration are the major causes of blindness. The prevalence of low vision and blindness are influenced by age, sex; area, health care level, educational level, and environmental factors.
Chen
Jian-hua
JH
Beijing Institute of Ophthalmology, Tongren Hospital, Capital Medical University, Beijing 100730, China.
Xu
Liang
L
Hu
Ai-lian
AL
Sun
Bao-chen
BC
Li
Jian-jun
JJ
Ma
Ke
K
Xia
Cui-ran
CR
Cui
Tong-tong
TT
Zheng
Yuan-yuan
YY
Li
Yi-bin
YB
Zhang
Rong-xiu
RX
Yang
Hua
H
Sun
Xiu-ying
XY
Zou
Yang
Y
Wang
Yan
Y
Ma
Bin-rong
BR
D000328:Adult; D000368:Aged; D001766:Blindness / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012737:Sex Factors; D014786:Vision Disorders / Q000453:epidemiology* / Q000209:etiology