Relationships among visual acuity, risk of acute myocardial infarction, and stroke: a nationwide cohort study in south korea

Purpose: Visual impairment (VI) is highly prevalent in the elderly and is associated with functional decline. Previous research demonstrated an association between VI and cardiovascular events, but investigations have yet to be conducted in general population samples. We evaluated the relationship between visual acuity (VA) and development of cardiovascular diseases (CVD) in a nationwide Korean population. Methods: This is a nationwide retrospective cohort study. We used the National Health Information Database of the National Health Insurance Service of Korea to identify subjects who participated in the National Health Insurance Service health screening program in 2012. We monitored 5,941,761 subjects for the development of cardiovascular diseases for a period of 5 years. Results: After adjustments for age, sex, and other covariates, with subjects having a visual acuity better than 20/20 as the reference group, the adjusted hazard ratios (HRs) and 95% confidential intervals (CI) for acute myocardial infarction and stroke were visual acuity between 20/20 and 20/60, 1.073 (95% CI 1.053, 1.094) and 1.151 (95% CI 1.132, 1.171), respectively; for visual acuity between 20/60 and 20/200, 1.236 (95% CI 1.197, 1.277), and 1.336 (95% CI 1.302, 1.371), respectively; and for visual acuity worse than 20/200, 1.325 (95% CI 1.285, 1.366) and 1.383 (95% CI 1.349, 1.418), respectively. Conclusion: Subjects with lower VA had higher risks of acute myocardial infarction and stroke. These results suggest that low VA is an independent risk factor for CVD.