Prevalence and risk factors of uncorrected refractive error among an elderly Chinese population in urban China: a cross-sectional study

OBJECTIVES: To investigate the prevalence and risk factors of uncorrected refractive error (URE) in an elderly urban Chinese population in China. DESIGN: A population-based cross-sectional study. METHODS: The study was conducted using a cluster random sample of residents aged 50 years or older living in the Jiangning Road subdistrict, Shanghai, China. All participants underwent a standardised interview and eye examinations, including presenting visual acuity (PVA) and best-corrected visual acuity (BCVA) between November 2012 and February 2013. URE was defined as an improvement of two lines or more in the BCVA compared with the PVA in the better eye of <20/40. RESULTS: A total of 1999 subjects (an 82.5% response rate) completed both the questionnaire and ophthalmic examination. The prevalence of URE was 20.1% (95% CI 18.0% to 22.2%) in the study sample. After age standardisation, the prevalence of URE in Chinese people aged 50 years or older was 18.7% (95% CI 17.0% to 20.4%). Under multiple logistic regression analysis, older age (per 1-year increase, OR 1.04, 95% CI 1.03 to 1.05) and a lower level of education (OR 1.34, 95% CI 1.07 to 1.69) were significantly related to URE. A history of ocular diseases (OR 0.71, 95% CI 0.55 to 0.92) was a protective factor for URE. CONCLUSIONS: URE is highly prevalent among the elderly urban Chinese population, which should raise awareness of the URE burden in China to meet the Vision 2020 goal to eliminate preventable blindness.