Association between refractive errors and horizontal strabismus: the Korea National Health and Nutrition Examination Survey

PURPOSE To investigate the association between refractive error and horizontal strabismus based on a Korean population-based survey. METHODS The study included 22,887 participants.5 years of age who participated in the Korea National Health and Nutrition Examination Survey (KNHANES) from 2008 to 2011. Refractive error was classified into myopia, hyperopia, astigmatism, and anisometropia. The association between refractive error and exodeviation or esodeviation was assessed using multivariate logistic regression analysis. RESULTS After adjusting for potential confounders, the analyses revealed an increased odds ratio (OR) for exodeviation with an increasing trend according to the severity of myopia (mild myopia, OR = 1.36 [95% CI, 1.11-1.66]; moderate myopia, OR = 1.75 [95% CI, 1.362.26]; severe myopia, OR 5 2.01 [95% CI, 1.50-2.69]; P-trend < 0.001). Hyperopia was not associated with exodeviation (P = 0.273). There were also significant associations for exodeviation with astigmatism (OR = 1.36 [95% CI, 1.16-1.59; P < 0.001]) and anisometropia (OR = 1.78 [95% CI, 1.38-2.30; P < 0.001]) In comparison, esodeviation was significantly associated with hyperopia (OR, 10.24 [95% CI, 4.43-23.70; P < 0.001]) and anisometropia (OR, 5.16 [95% CI, 2.27-11.76; P < 0.001]), while no significant association was found with myopic degree (P = 0.170) or astigmatism (P = 0.816). CONCLUSIONS Refractive error was closely associated with exodeviation and esodeviation. These risk associations should be considered when managing refractive errors.