Myopic Shift and Outdoor Activity among Primary School Children: One-Year Follow-Up Study in Beijing

Abstract

PurposeTo assess whether a change in myopia related oculometric parameters of primary school children in Beijing was associated with indoors and outdoors activity.MethodsThe longitudinal school-based study included school children who were examined in 2011 and who were re-examined in 2012. The children underwent a comprehensive eye examination including ocular biometry by optical low-coherence reflectometry and non-cycloplegic refractometry. Parents and children had a detailed interview including questions on time spent indoors and outdoors.ResultsOut of 681 students examined at baseline, 643 (94.4%) returned for follow-up examination. Within the one-year period, mean time spent daily outdoors increased by 0.4±0.9 hours, mean axial length by 0.26±0.49 mm, the ratio of axial length divided by anterior corneal curvature (AL/CC) by 0.03±0.06, and myopic refractive error by −0.06±0.89 diopters. In multivariate analysis, elongation of axial length was significantly associated with less total time spent outdoors (P = 0.02; standardized coefficient beta −0.12) and more time spent indoors with studying (P = 0.007; beta: 0.14) after adjustment for maternal myopia (P = 0.02; beta: 0.12). An increase in AL/CC was significantly associated with less time spent outdoors (P = 0.01; beta:−0.12) after adjustment for paternal myopia (P = 0.003; beta: 0.15) and if region of habitation was excludedors for leisure (P = 0.006; beta:−0.13), with less total time spent outdoors (P = 0.04; beta:−0.10), or with more time spent i. An increase in myopic refractive error, after adjustment for age, was significantly associated with less time spent outdo ndoors with studying (P = 0.005; beta: 0.13).ConclusionsA change in oculometric parameters indicating an increase in myopia was significantly associated with less time spent outdoors and more time spent indoors in school children in Greater Beijing within a study period of one year. Our study provides additional information on the potentially helpful role of outdoors activity in the prevention of myopia. Public health care measures such as school agendas may potentially take it into account.

Rola aktywności zewnętrznej w rozwoju krótkowzroczności u dzieci w wieku szkolnym

“…Most authors believe that outdoor activity reduces the prevalence of myopia in children [2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17]. We also observed this relationship in our paper.…”

“…It is also known that outdoor activity reduces the prevalence of myopia -table 1 [2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17]. However, lately a number of papers have been published that determined that outdoor activity does not have an influence on the prevalence of myopia -table 2 [18,19,20,21,22,23,24].…”

Parapapillary Gamma Zone and Progression of Myopia in School Children: The Beijing Children Eye Study

“…The study design and the study population have been described in detail recently. 12,13 The eye examination carried out for all study participants consisted of measurement of the refractive error and an assessment of visual acuity, an evaluation of ocular motility, slit lamp-assisted biomicroscopy of the anterior and posterior segments of the eye, and nonmydriatic digital fundus photography (458; CR-DGI camera; Canon Inc., Tokyo, Japan). By applying optical low-coherence reflectometry (Lenstar 900 optical biometer; Haag-Streit, Koeniz, Switzerland), the ocular biometric parameters of central corneal thickness, corneal curvature radius, anterior chamber depth, lens thickness, and axial length were measured in the right eyes of all children.…”

Axial Length/Corneal Radius of Curvature Ratio Assessment of Posterior Sclera Reinforcement for Pathologic Myopia

“…Instead, with increasing AL, the cornea may actually steepen, perhaps because of me-Ophthalmologica 2018;239:128-132 DOI: 10.1159/000484485 chanical stretching of the globe [10]. Considering that the refractive error of an eye is interrelated with both AL and refractive components (such as cornea and lens) of the eye, AL/corneal radius of curvature (CRC) ratio has been suggested as a proxy for refractive error [11][12][13][14][15][16][17]. The AL/ CRC value is associated with the development of myopia and may be a more useful marker of progress toward myopia than AL alone.…”