Changes of hyperopia reserve and other eye parameters among Chinese children aged 3-6 years old

Abstract

Purpose Track refractive changes in preschool children to explore the characteristics of refractive changes, further delineate refractive status and provide data for the prevention of refractive errors in preschool children. Methods The refractive data of 26,528 preschoolers in 2021 and 16383 ones lasting for 2 years(2020 and 2021) aged 3–6 years were collected from different kindergartens in Suzhou High-tech Zone for the study(Until 23 July 2021). The refractive data of every participant was measured with the Welch Allyn Spot on non-cycloplegic refraction. A follow-up for all the included participants was performed. The spherical equivalent change was calculated, subsequently, the characteristics related to the change were performed. Results The chi-square test of 26528 preschoolers in 2021 showed a higher prevalence of hyperopia in boys (χ2 = 4.299, P = 0.038), and a higher prevalence of hyperopia reserve deficiency in boys (χ2 = 11.987, P = 0.001). And there are the trends for myopia (χ2 = 26.398, P < 0.001), astigmatism (χ2 = 58.838, P < 0.001), hyperopia reserve deficiency (χ2 = 24.290, P < 0.001) to increase with age. Trackable data shows the incidence of refractive errors (= Number of new patients in 2021/number of non-patients in 2020). After Chi-square that the incidence of hyperopia, astigmatism and myopia was statistically different at different ages and the incidence of the three at 5 years-old are at the high level. The further analysis of the newly developed people with hyperopia reserve deficiency shows the decline rate of hyperopia reserve has slowed down with age, the rate of decline of 2–3 and 3–4 are faster than 4-5and 5–6 significantly. Conclusion In preschool, boys possess higher hyperopia than girls; and, as age increases, but the increase rate of hyperopia reserve deficiency for girls is faster with the growth of age. There were the special incidence of hyperopia and astigmatism at 5 years old. And we should watch out for sharp changes in early hyperopia reserve. At the same time, the serious lack of hyperopia reserve(19%) of children in Suzhou also sounded an alarm for myopia prevention.