Prevalence of glaucoma in the elderly population in Taiwan: The Shihpai Eye Study

Background: This study aimed to evaluate the prevalence, characteristics, and the awareness status of glaucoma in an elderly Chinese population. Methods: A total of 460 individuals aged ≥72 years were enrolled in this cross-sectional community-based eye disease screening program. Glaucoma was diagnosed according to the diagnostic criteria proposed by the International Society of Geographical and Epidemiological Ophthalmology. Characteristics of subjects with primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG) were described and compared between groups using Mann-Whitney U and Fisher’s exact tests. Results: Forty subjects were diagnosed with glaucoma, including 17 subjects with POAG, 22 with PACG, and one with secondary glaucoma. The estimated prevalence of glaucoma, POAG, and PACG was 8.7%, 3.7%, and 4.8%, respectively. In total, 71% of the subjects with PACG and 77% of POAG subjects presented with a normal intraocular pressure (IOP) of <19 mmHg. The demographic and ocular characteristics were similar between the two groups; however, subjects with POAG had a longer axial length and smaller vertical disc diameter than those with PACG. Further, 95% of the glaucoma subjects ever visited the eye clinic, but only 32.5% of them were aware of the disease. Conclusion: Glaucoma is prevalent in the elderly population in Taiwan, but the diagnostic rate and disease awareness are low.