Prevalence and risk factors for angle-closure disease in a rural Northeast China population: a population-based survey in Bin County, Harbin

Purpose: To estimate the prevalence of primary angle-closure glaucoma (PACG), primary angle closure (PAC) and primary angle-closure suspect (PACS) and associated risk factors for PACG in a rural population in Northeast China. Methods: A population-based survey was conducted in Bin County, Harbin, Northeast China. Glaucoma was diagnosed using the International Society of Geographical and Epidemiological Ophthalmology (ISGEO) criteria. All subjects underwent a complete ophthalmic examination. Results: A total of 4956 (86.01%) of 5762 subjects aged 40 years or older were examined. The mean intraocular pressure (IOP) of the right eyes was 14.0 mmHg. The mean vertical cup-to-disc ratio of the right and the left eyes was 0.31 and 0.31, respectively. The prevalence of PACG, PAC and PACS was 1.57% [ 95% confidence interval (CI), 1.469-1.671], 1.33% (95% CI, 1.236-1.424), and 4.68% (95% CI, 4.541-4.819), respectively. Among all PACG subjects, 42 (53.84%) had elevated IOP >21 mmHg in either eye and 37 (47.44%) had been treated by laser, surgical iridectomy or trabeculectomy. Sixty-four subjects (82.05%) had vision impairment of varying degrees. Multivariate analysis revealed that old age, family history of PACG, constipation and IOP were significant independent risk factors. Conclusions: Primary angle-closure glaucoma was a disease of high prevalence in rural Northeast China. Old age, family history of PACG, constipation and IOP were significant independent risk factors for PACG.