The Tajimi Study report 2: prevalence of primary angle closure and secondary glaucoma in a Japanese population

Abstract

Purpose: To determine the prevalence of primary angle-closure glaucoma (PACG), secondary glaucoma (SG), and all glaucoma in a Japanese population as a part of the Tajimi Study.

Design: Population-based epidemiological survey.

Participants: A random sample of residents 40 years or older from Tajimi, Japan.

Intervention: Each subject underwent a screening program comprising an interview and an ophthalmic examination, including Goldmann applanation tonometry, slit-lamp examination, a van Herick test, fundus photography, and a screening visual field (VF) test using frequency-doubling technology. If glaucoma was suspected, the subject was referred for a definitive examination that included slit-lamp examination, gonioscopy, intraocular pressure measurement, a VF test, and optic disc and fundus examination. A diagnosis of PACG or SG was made based on slit-lamp examination, gonioscopy, optic disc appearance, and perimetric results.

Main outcome measures: Prevalences of PACG, SG, and all cases of glaucoma.

Results: Of 3870 eligible people, 3021 (78.1%) participated in the study. Estimated prevalences of PACG and SG in those over 40 years were 0.6% (95% confidence interval [CI], 0.4%-0.9%) and 0.5% (95% CI, 0.2%-0.7%), respectively. Prevalences of all glaucoma and glaucoma/suspected glaucoma were estimated to be 5.0% (95% CI, 4.2%-5.8%) and 7.5% (95% CI, 6.5%-8.4%), respectively.

Conclusions: Prevalences were 0.6%, 0.5%, and 5.0%, respectively, for PACG, SG, and all glaucoma in subjects over 40 years from Tajimi, Japan.