The prevalence and types of glaucoma in an urban Indian population: the Singapore Indian Eye Study.

Purpose: To determine the prevalence and types of glaucoma in an urban Singaporean Indian population.

Methods: The Singapore Indian Eye Study (SINDI) was a population-based, cross-sectional survey that examined 3400 (75.6% response) persons aged 40 to 80 years. Participants underwent a standardized examination including slit-lamp biomicroscopy, Goldmann applanation tonometry, and dilated optic disc assessment. Participants suspected to have glaucoma also underwent visual field examination (24-2 SITA standard, Humphrey Visual Field Analyzer II), gonioscopy, and repeat applanation tonometry. Glaucoma was defined according to International Society for Geographical and Epidemiologic Ophthalmology criteria.

Results: Of the 3400 participants, 78 (2.29%) had diagnosed glaucoma, giving an age-standardized prevalence of 1.95% (95% confidence interval [CI], 1.5%-2.5%). The age-standardized prevalence of primary open-angle glaucoma (POAG) was 1.25% (95% CI, 0.89%-1.73%), primary angle-closure glaucoma (PACG) 0.12% (95% CI, 0.04%-0.33%), and secondary glaucoma 0.55% (95% CI, 0.35%-0.86%). The mean IOP among the participants in the normal group in the study population was 15.6 ± 2.6 mm Hg and 17.7 ± 6.1 mm Hg in subjects with glaucoma (P = 0.003). The mean central corneal thickness (CCT) in the normal study population was 540.31 ± 33.79; the mean CCT in subjects with POAG (529.8 ± 30.8 μm) was statistically different from the normal study group (P = 0.003).

Conclusions: The prevalence of glaucoma among Singaporean Indians 40 years of age and older in Singapore was 1.95%, approximately half that of the Chinese and the Malay persons in Singapore. As in other Asian studies, POAG was the main form of glaucoma accounting for nearly 60% of cases.