Association of hyperopia reserve with the severity of parental refractive status in pre-school Chinese children--Beijing Hyperopia reserve study

Abstract

Purpose : Beijing Hyperopia Reserve Study is a prospective observational study to investigate 3-years trajectory of the hyperopia reserve elimination in a kindergarten-based sample of Chinese children 3 through 6 years of age in an urban city, Beijing. The baseline data was collected in 2020. Parental myopia was associated with a high risk of early-onset myopia. In addition, myopia and high myopia seem to have different patterns of inheritance, and more severe myopia leads to an increased risk of myopia in children aged 12 to 15 years old. Limited data of those associations is shown in children before the onset of myopia. Hyperopia reserve is a refractive status that precedes myopia and attracts wide attention both in parents and clinicians. We conducted this study to explore the impact of severity of parental myopia on hyperopia reserve status in Chinese pre-school children.

Methods : The study enrolled 2111 pre-school children from 22 randomly selected kindergartens including 1011 girls (2022 eyes) and 1100 boys (2200 eyes). Among them, 494, 844, 500, 273 children were 3, 4, 5, 6 years old. All children were taken cycloplegic refraction by using cyclopentolate 1%. Refraction was recorded in spherical equivalent, appreciated as hyperopia reserve. Parents were asked to complete a questionnaire about the severity of refractive status (normal; mild myopia <-3D; moderate myopia ≥-3D and≤-6; high myopia >-6D) and near/outdoor activities time and reading habits.

Results : The mean hyperopia reserve was 1.11±0.97 diopter and the mean axial length was 22.3±0.7mm in all children. In total, 90.7% of children had at least one myopic parent. There was a descending trend of hyperopia reserve and axial length with increasing severity of parental refractive status (Fig a and b). It is noted that the mean axial length in children in mild-high, mod-high, and high-high was beyond the average of the whole population (Fig b). The hyperopia reserve was correlated with neither indoors (P=0.631) nor outdoor activity time (P=0.330).

Conclusions : More severe myopia in parents was associated with less hyperopia reserve in preschool children. The children with highly myopic parents have longer axial lengths and may have higher risks of being myopia.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.

 

The distribution of hyperopia reserve, axial length and AL/CR with increasing severity of parental refractive status