Prevalence and risk factors of undiagnosed age-related macular degeneration: the Korea National Health and Nutrition Examination Survey 2017–2020

This study aimed to evaluate the prevalence and risk factors for undiagnosed age-related macular degeneration (AMD) in the Korean population. This cross-sectional study utilized data from the Korea National Health and Nutrition Examination Survey (KNHANES 2017-2020), which included a total of 13,737 subjects of 40 years or older. Cases in which AMD was identified through imaging interpretation of the KNHANES data, but the patients had not received a prior medical diagnosis of AMD, were classified as undiagnosed AMD. The prevalence and risk factors for undiagnosed AMD were analyzed. Among the patients identified to having AMD through KNHANES, the prevalence of undiagnosed AMD was 95.25% (95% confidence interval [CI], 94.13-96.37). Multivariate analysis revealed that a low level of education was significantly associated with a higher risk of undiagnosed AMD (p = 0.0066). A low level of education was also linked to a higher risk of undiagnosed early AMD (p = 0.0369) and neovascular AMD (p = 0.0399). Aging was strongly associated with an increased risk of undiagnosed geographic atrophy (p < 0.0001). Physical activity was associated with a lower risk of undiagnosed neovascular AMD (p = 0.0107). The high prevalence of undiagnosed AMD in the Korean population highlights the need for regular fundus examinations to facilitate accurate detection of AMD. Low education level emerged as a significant risk factor for undiagnosed AMD, emphasizing the importance of targeted interventions for this population to reduce the risk of visual impairment due to AMD.