Prevalence and risk factors of hypertensive retinopathy in South Korea based on national health survey data

Abstract

This study investigated the prevalence and risk factors of moderate to severe hypertensive retinopathy among non-diabetic South Korean adults using data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2008-2011. Hypertensive retinopathy was defined through standardized retinal image grading. A multivariable logistic regression model was developed using weighted analysis and predictor selection based on pathophysiological relevance and multicollinearity diagnostics. Final model features included age, systolic blood pressure, HbA1c, total cholesterol, creatinine, and hemoglobin. Among 5,075 participants, the weighted prevalence of moderate to severe hypertensive retinopathy was 0.8%. The prevalence rate increased with higher systolic blood pressure levels. The model demonstrated moderate discrimination, with an average area under the receiver operating characteristic curve (AUC) of 0.721 in 5-fold cross-validation and 0.679 in external validation using the KNHANES 2012 dataset. External validation was performed using averaged predictions from the five internally validated models. The relatively low prevalence of hypertensive retinopathy compared to Western populations may reflect differences in hypertension control, lifestyle, or genetic susceptibility. Future research should explore retinal image analysis and longitudinal datasets to enhance early detection and clarify the systemic implications of hypertensive retinopathy.