Prevalence and causes of visual impairment in rural Myanmar

Objective: To determine the prevalence and causes of visual impairment in the Meiktila district of central, rural Myanmar. Design: Population-based cross-sectional study. Participants: Random, stratified, cluster sampling of the inhabitants 40 years of age and older from villages in the Meiktila district was performed; 2481 eligible participants were identified and 2076 participated in the study. Methods: The ophthalmic examination included presenting and pinhole Snellen visual acuity with an illiterate E chart, slit-lamp examination of the anterior segment, and dilated stereoscopic fundus examination. The principal cause of visual impairment was recorded. Main Outcome Measures: Visual impairment and blindness were defined by both presenting and corrected visual acuity according to World Health Organization criteria: better eye < 6/18 and < 3/60, respectively. Results: Comprehensive examinations, including Snellen visual acuity, were performed on 2073 participants (83.6%) The prevalence estimate of presenting visual impairment was 40.4% (95% confidence interval [Cl], 36.1-44.7) and of presenting blindness was 8.1% (95% Cl, 6.5-9.9). After pinhole correction, the corresponding prevalences were 26.8% (95% Cl, 23.5-30.1) and 5.3% (95% Cl, 4.0-6.6). Cataract, uncorrected refractive error, and glaucoma were the most common causes of visual impairment. Conclusions: Visual impairment and blindness remain major public health problems in rural Myanmar. Specific programs directed toward reducing the cataract burden need to be implemented.