Risk factors for astigmatism in preschool children: The multi-ethnic pediatric eye disease and baltimore pediatric eye disease studies

Objective: To evaluate risk factors for astigmatism in a population-based sample of preschool children. Design: Population-based cross-sectional study. Participants: Population-based samples of 9970 children ages 6 to 72 months from Los Angeles County, California, and Baltimore, Maryland. Methods: A cross-sectional study of children participating in the Multiethnic Pediatric Eye Disease Study and the Baltimore Eye Disease Study was completed. Data were obtained by clinical examination or by in-person interview. Odds ratios and 95% confidence intervals (CI) were calculated to evaluate potential associations between clinical, behavioral, or demographic factors and astigmatism. Main Outcome Measures: Odds ratios (ORs) for various risk factors associated with astigmatism. Results: Participants with myopia (≤-1.0 diopters) were 4.6 times as likely to have astigmatism (95% CI, 3.565.96) than those without refractive error, whereas participants with hyperopia (<+2.00 diopters) were 1.6 times as likely (95% CI, 1.391.94). Children 6 to <12 months of age were approximately 3 times as likely to have astigmatism than children 5 to 6 years of age (95% CI, 2.283.73). Both Hispanic (OR, 2.38) and African-American (OR, 1.47) children were as likely to have astigmatism than non-Hispanic white children. Furthermore, children whose mothers smoked during pregnancy were 1.46 times (95% CI, 1.141.87) as likely to have astigmatism than children whose mothers did not smoke. Conclusions: In addition to infancy, Hispanic and African-American race/ethnicity and correctable/modifiable risk factors such as myopia, hyperopia, and maternal smoking during pregnancy are associated with a higher risk of having astigmatism. Although the prevalence of smoking during pregnancy is typically low, this association may suggest etiologic pathways for future investigation. Financial Disclosure(s): The authors have no proprietary or commercial interest in any of the materials discussed in this article.