Purpose To investigate the prevalence and causes of low vision and blindness in a rural northern Chinese population.
Methods A cross-sectional, population based survey was conducted between July 2010 and September 2010 in Ci County, Hebei Province of Northern China. Individuals aged 7 years or more residing in Lucunying Town located within Ci County were all selected and invited to participate the study. Low vision and blindness were defined using the World Health Organization categories of visual impairment. Principal causes of low vision and blindness were also determined according to WHO definitions.
Results Among the 24539 residents in year 2010, 19359 (78.9%) aged older than 7 years participated in the study, and 19133 (78.0%) had valid visual acuity (VA) data. Based on presenting VA (PVA), the prevalence of visual impairment, low vision and blindness in the examined population was 2.7%, 2.4% and 0.3%, respectively, and the prevalence of visual impairment was higher among women than men (3.6% vs. 1.8%) and increasing with age (10.6% in residents 50 years of age or older). Cataract (60.7%) was the predominant cause for PVA defined visual impairment in this population, followed by uncorrected refractive error (18.8%), myopic maculopathy (7.0%), and glaucoma (5.2%). Cataract (69.2%), glaucoma (10.3%), absence ⁄ disorganization of bulb (10.3%), and myopic maculopathy (7.7%) were leading causes of blindness based on best corrected VA (BCVA).
Conclusion Cataract and refractive error are the most frequent causes of visual impairment in this Chinese population, which are potentially treatable. Our results highlight the need for eye health care services of visual impairment in rural China.