A review on the epidemiology of myopia in school children worldwide

Abstract

Background: Due to high prevalence myopia has gained importance in epidemiological studies. Children with early onset are at particular risk of complications associated with myopia, as progression over time might result in high myopia and myopic macular degeneration. Both genetic and environmental factors play a role in the increasing prevalence of myopia. The aim of this study is to review the current literature on epidemiology and risk factors for myopia in school children (aged 6-19 years) around the world. Main body: PubMed and Medline were searched for the following keywords: prevalence, incidence, myopia, refractive error, risk factors, children and visual impairment. English language articles published between were included in the study. Studies were critically reviewed for study methodology and robustness of data. Eighty studies were included in this literature review. Myopia prevalence remains higher in Asia (60%) compared with Europe (40%) using cycloplegic refraction examinations. Studies reporting on non-cycloplegic measurements show exceptionally high myopia prevalence rates in school children in East Asia (73%), and high rates in North America (42%). Low prevalence under 10% was described in African and South American children. In recent studies, risk factors for myopia in schoolchildren included low outdoor time and near work, dim light exposure, the use of LED lamps for homework, low sleeping hours, reading distance less than 25 cm and living in an urban environment. Conclusion: Low levels of outdoor activity and near work are well-established risk factors for myopia; this review provides evidence on additional environmental risk factors. New epidemiological studies should be carried out on implementation of public health strategies to tackle and avoid myopia. As the myopia prevalence rates in noncycloplegic studies are overestimated, we recommend considering only cycloplegic measurements.

<p>The Prevalence of Myopia and Factors Associated with It Among Secondary School Children in Rural Vietnam</p>

“…Within countries, the prevalence of myopia may also vary between different areas. 41 In the present study, we conducted only research in a rural area, and our results may be lower than those of studies conducted in urban areas.…”

“…This result is similar to those of other studies, which reported that the likelihood of myopia increased with age (or school grade). 18,23,24,28,35,36,39,41 As such, developing reasonable and appropriate learning plans that include an emphasis on eye health may be a good solution to prevent school-age myopia and should be considered by education policymakers.…”

Prevalence of myopia in Indian school children: Meta-analysis of last four decades

“…obtained in other countries as well because myopia tends to develop after the natural curve of emmetropisation is over [3,88,89,95]. India is geographically and demographically a large country with distinct regional identity and characteristics.…”

The Combined Effect of Low-dose Atropine with Orthokeratology in Pediatric Myopia Control: Review of the Current Treatment Status for Myopia

“…Juvenile-onset myopia is the most common variety [4], with its peak incidence during elementary school and progression through the teenage years [5]. Thus, it is crucial to make a myopia onset prediction between the ages of 8 and 9 years old [6,7].…”