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[The prevalence of blindness caused by primary angle closure glaucoma in middle-aged Chinese population: a systematic review and meta-analysis].

Objective: To evaluate the rate of blindness caused by primary angle closure glaucoma (PACG) in Chinese population of more than 40 years old, and to explore the effectiveness of a prevention and treatment system on PACG. Methods: We searched the databases of Pubmed, ScienceDirect, Springer Link, CNKI and Wanfang Data and collected all the original studies of the prevalence and blindness of angle closure glaucoma in China. The population was limited to over 40 years old. The research site was limited to the community-based, while the published time was not limited. Two researchers completed the literature search, data extraction and methodological quality assessment independently, with same criteria. Meta analysis was performed using R software. Results: Five papers were included in this study finally. A total of 26 437 cases of natural population over the age of 40 were observed, and 306 cases of angle closure glaucoma were found, of which 113 cases had binocular or monocular blindness caused by PACG. The random effect model meta-analysis results showed that the overall blindness rate was 38.3% [95%CI (28.1%, 49.6%)]. In Beijing, where the prevention and treatment system was well established, the blindness rate was far lower than that in the areas where the system was poorly established. Compared with the past, the blindness rate caused by PACG in Beijing decreased sharply. Conclusions: The rate of blindness caused by PACG is still high in the mainland of China. The prevention and treatment system is effective and worth promoting. (Chin J Ophthalmol, 2017, 53: 373-377).