Prevalence of reduced visual acuity among preschool children in eastern China and comparison at a 5-year interval

摘要

Importance Assessing the prevalence of reduced visual acuity and its change over time has significant public health importance. This study evaluated prevalence of reduce visual acuity in children aged 48-60 months, and compared it with previous data. Background Previous studies reported prevalence of reduced visual acuity in preschool children, but none has evaluated prevalence change in the same area. Design Nanjing Eye Study, a longitudinal population-based study. Participants Two thousand three hundred eligible children. Methods Comprehensive eye examinations. Main Outcome Measures Uncorrected visual acuity, presenting visual acuity, best-corrected visual acuity, anterior segment and fundus examination, cycloplegic refraction. Results Based on the worse and better eye, respectively, 6.8% and 3.5% had reduced uncorrected visual acuity and 4.0% and 1.4% had reduced presenting visual acuity. Compared to rates in the Nanjing Paediatric Vision Project carried out 5 years ago in the same area, the prevalence rates of reduced uncorrected visual acuity were significantly higher (6.8% vs. 5.3%, P = 0.04 for worse eye; 3.5% vs. 2.1%, P = 0.0049 for better eye), but there was no significant increase in rates of reduced presenting visual acuity (4.0% vs. 3.7%, P = 0.63 for better eye; 1.4% vs. 1.7%, P = 0.43 for worse eye). The prevalence rate of glasses prescription is higher in this study (4.5% vs. 3.1%, P = 0.02). Conclusions and Relevance Prevalence of reduced uncorrected visual acuity increased significantly, indicating that Chinese children are faced with more vision-threatening factors. However, more children with refractive errors got appropriate correction.