Distribution, Progression, and Associated Factors of Refractive Status of Children in Lhasa, Tibet, after COVID-19 Quarantine

• Type of Material: Article
• Authors: Yao Yao, Capital Medical University; Jing Fu, Capital Medical University; Jiawen Liu, Emory University; Lei Li, Capital Medical University; Weiwei Chen, Capital Medical University; Zhaojun Meng, Capital Medical University; Wei Dai, Capital Medical University
• Language: English
• Date: 2022-06-01
• Publisher: KARGER
• Publication Version: Final Published Version
• Copyright Statement: © 2022 by S. Karger AG, Basel
• License: Creative Commons Attribution-NonCommercial 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1159/000522548
• Title of Journal or Parent Work: OPHTHALMIC RESEARCH
• Volume: 65
• Issue: 3
• Start Page: 321
• End Page: 327
• Grant/Funding Information: The study was financially supported by the National Natural Science Foundation of China (Grant No. 82070998); Capital Research Project of Clinical Diagnosis and Treatment Technology and Translational Application, Beijing Municipal Science & Technology Commission (Z201100005520044); and “Yangfan” clinical technology innovation project, Beijing Municipal Administration of Hospitals (XMLX202103).
• Keywords: ERROR; Science & Technology; SCHOOL; OUTDOORS; AXIAL LENGTH; MYOPIA; OCULAR BIOMETRY; Myopia; AGE; Life Sciences & Biomedicine; GROWTH; Coronavirus disease-19; VISUAL IMPAIRMENT; Ophthalmology; Children; Tibetan; Refractive error
• Research Categories: Health Sciences, Opthamology

Abstract

Introduction: Uncorrected refractive error is one of the major causes of visual impairment in children and adolescents worldwide. During the COVID-19 epidemic, home isolation is considered a boost to the progression of children's myopia. Under geographical conditions of high altitude and strong sunshine, the Tibetan plateau is the main residence of the Tibetan population, where little information is available about the refractive status and developmental trajectory. Therefore, this article aimed to evaluate the distribution, progression, and associated factors of the refractive status in second-grade children in Lhasa after COVID-19 quarantine. Materials and Methods: Students from 7 elementary schools completed comprehensive ocular examinations in the Lhasa Childhood Eye Study. Data regarding cycloplegic refraction and corneal biometry parameters, including axial length (AL), corneal power, anterior chamber depth (ACD), and other demographic factors, were analyzed. Results: A total of 1,819 students were included, with a mean age of 7.9 ± 0.5 years, of which 961 were boys (52.8%), and 95.1% were Tibetan. The prevalence of myopia, emmetropia, mild hyperopia, and hyperopia was 10.94%, 24.02%, 60.80%, and 4.24%, respectively. Besides, the average cycloplegic spherical equivalent refraction (SER) was +1.07 ± 0.92 diopter (D) before the COVID-19 quarantine and +0.59 ± 1.08D after the quarantine (p < 0.05), with a growth rate of 7%. Moreover, the prevalence of hyperopia in girls was significantly higher than that of boys (p < 0.001). Nonetheless, the proportion of myopia and emmetropia was similar (p = 0.75). Meanwhile, children in suburban schools had a significantly lower proportion of myopia (p < 0.001). The average AL, ACD, lens power (LP), and AL-to-corneal radius (AL/CR) ratio were 22.79 ± 0.78 mm, 3.54 ± 0.21 mm, 25.12 ± 1.48D, and 2.93 ± 0.08, respectively. The results of AL, ACD, and AL/CR for girls were significantly lower than for boys, while the result of LP is the opposite (p < 0.001). Finally, multivariate regression analysis revealed that SER was negatively correlated with AL, LP, and AL/CR ratio, while positively correlated with CR and ACD (p < 0.001). Conclusion: This study found that after the COVID-19 confinement, myopia progressed faster in Lhasa children but was still significantly lower than that of plain cities in China. Compared to short-term confinement, this acceleration was more likely related to the growth and general trend of myopia in children. Collectively, these findings help to explore the differences in ocular growth and development among children of different ethnic groups.