Characteristics of astigmatism in school-age children aged 5 to 13 years in northeast Sichuan: a cross-sectional school-based study.

Background: Astigmatism is closely associated with myopia progression, vision loss, eye fatigue and amblyopia, which seriously endangers children's eye health. This study aims to investigate the prevalence and characteristic distribution of astigmatism in children in Langzhong City, providing valuable insights for allocating resources and develop prevention and control strategies.

Methods: A cross-sectional study and random sampling survey were conducted. Between January and November 2021, 21,415 students aged 5 to 13 years from 14 primary schools in Langzhong City underwent non-cycloplegic refractive testing using autorefraction. The data on myopia were analyzed using SPSS (Statistical Package for the Social Sciences) version 23.0.

Results: The inclusion criterion was set at an absolute astigmatism value of ≥0.50D. Among the 21,415 children studied, 61.70% were found to have astigmatism. The prevalence of astigmatism varied significantly across different grades (χ²=501.414, P<0.001). The predominant types of astigmatism were mild astigmatism (0.50-1.00D) and with-the-rule astigmatism. Mixed astigmatism was primarily observed in children in grades 1 and 2, while compound myopic astigmatism was more common in children in grades 3 to 6. These differences were statistically significant. As the degree of astigmatism increased, the proportions of against-the-rule astigmatism, oblique astigmatism, compound myopic astigmatism, and simple hyperopic astigmatism decreased, whereas the proportions of with-the-rule astigmatism, mixed astigmatism, and compound hyperopic astigmatism increased.

Conclusions: The prevalence of astigmatism among school-age children aged 5 to 13 years in northeast Sichuan is notably high, with compound myopic astigmatism and with-the-rule astigmatism being the most common types. Regular refractive examinations are crucial for the early detection and management of astigmatism.