Association between Renal Function and Open-Angle Glaucoma: The Korea National Health and Nutrition Examination Survey 2010–2011

Purpose To investigate the relationship between renal function and primary open-angle glaucoma (POAG) in a South Korean population. Design A population-based, cross-sectional survey using a multistage, stratified, probability-clustered sampling method from the Korean National Health and Nutrition Examination Survey (KNHANES). Participants A total of 5971 participants at least 40 years of age were selected from the KNHANES between 2010 and 2011. Methods A standardized protocol was used to interview every participant and perform comprehensive ophthalmic examinations. Glaucoma was diagnosed according to criteria from the International Society of Geographical and Epidemiological Ophthalmology. The estimated glomerular filtration rate (eGFR) was calculated from serum creatinine concentrations using the Cockcroft–Gault formula, as follows: eGFR = (140 − age) × mass (kg) × (0.85 for female subjects)/(72 × serum creatinine (mg/dl). The presence of proteinuria also was assessed. Subjects were stratified by eGFR into the following groups: ≥90, 60–90, 45–59, and <45 ml/min/1.73 m². Main Outcome Measures Renal function and POAG. Results The overall prevalence of POAG was 5.5%. The prevalence of low eGFR (<60 ml/min/1.73 m²) was 9.5%, and the prevalence of eGFR <45 ml/min/1.73 m² was 2.0%. Multiple linear regression models were adjusted for age, sex, and other confounding factors (high-density lipoprotein level, blood glucose concentration, blood pressure, and intraocular pressure). These models revealed a positive correlation between the presence of POAG and low eGFR (odds ratio [OR], 2.88; 95% confidence interval [CI], 1.44–5.76). No association was found between proteinuria and POAG (adjusted for age, sex, and other confounding factors; OR, 0.96; 95% CI, 0.29–3.17). Conclusions This population-based study of South Korean adults showed that low eGFR levels are independently associated with POAG.