To assess the prevalence and types of glaucoma in a rural population in northern China.
Population-based cross-sectional study.
Subjects randomly selected from the population 40 years of age and older in Kailu County, Tongliao, Inner Mongolia.
Each subject underwent a screening examination consisting of an interview and ophthalmic examinations, including applanation tonometry, central corneal thickness, gonioscopy, slit-lamp examination, dilated fundus evaluation, and a screening visual field test using frequency-doubling technology.
Glaucoma was diagnosed using International Society of Geographical and Epidemiological Ophthalmology criteria.
Of 5949 individuals 40 years of age and older, 5197 (87.36%) were examined. Of these, 169 (3.28%) had diagnosed glaucoma, giving an age- and gender-standardized prevalence of 2.90% (95% confidence interval, 2.02%-3.78%). The age- and gender-standardized prevalence of primary angle-closure glaucoma (PACG) was 1.42% (95% confidence interval, 0.82%-2.02%) and that for primary open-angle glaucoma (POAG) was 1.41% (95% confidence interval, 0.79%-2.02%). Of the 169 subjects with glaucoma, 54 (60%) and 3 (4.1%) had a previous known history of PACG or POAG, respectively. Unilateral blindness resulting from primary glaucoma was observed in 27 subjects (16.56%; 19 PACG/8 POAG), and bilateral blindness was present in 12 subjects (7.36%; 6 PACG/6 POAG). The prevalence of all types of glaucoma was increased with older age.
The adjusted prevalence of glaucoma in this Chinese population was 2.90%, comparable with other data from Asia. The ratio of PACG to POAG was approximately equal. More than 90% of POAG cases previously were undetected, and nearly 30% of subjects with glaucoma were blind in at least 1 eye.
The author(s) have no proprietary or commercial interest in any materials discussed in this article.