Prevalence Of Myopia In School Children Research Articles

Prevalence of myopia in schoolchildren of a highly urbanized city in Eastern Siberia

Myopia is one of the most urgent problems of modern ophthalmology. Statistics show that the number of children and adolescents suffering from myopia is steadily increasing worldwide. But it also noted that in different regions of the Russian Federation, the proportion of children who are diagnosed with myopia may differ markedly. Purpose: to determine the prevalence and structure of myopia in schoolchildren of the city of Krasnoyarsk, depending on age and gender. Materials and methods. A survey of 3005 students of secondary schools in the city of Krasnoyarsk aged from 6 to 18 years, including 1,421 schoolboys and 1,584 schoolgirls, was conducted. Refraction was determined after cycloplegia using the autorefractometry method. Results. The predominant type of refraction in primary school students of both fi elds is emmetropia, myopia is in second place and other refractive errors are in third place. The prevalence of myopia in schoolchildren increases as they grow up. At the same time, in the schools of the city of Krasnoyarsk, already in the primary grades in the group of subjects of both sexes, the proportion of students with myopia was 17.9 %, in the middle – 36.8 %, and by the high classes it reached 49.7 %. When considering the data obtained, depending on gender, approximately the same proportions of myopia were found in primary grades in both schoolgirls (19.2 %) and schoolchildren (16.7 %), in middle grades, a statistically significant predominance of myopic refraction in girls, compared with boys (42.8 and 29.5 %, respectively, p < 0.05). In high school, the proportion of myopia increases both in girls to 52.1 % and in boys to 47.2 %. The proportion of subjects with emmetropic refraction decreases as individuals of both sexes grow up. The percentage of other refractive errors remains without significant gender-age changes. Low myopia was the most common in all groups, but its percentage significantly decreased as they moved to higher grades, simultaneously with an increase in the proportion of moderate and high myopia. Conclusions. There is an increase in the prevalence of myopia in schoolchildren as they move to higher grades. A threefold increase in the proportion of myopia in high school compared with primary school was revealed. It is necessary to further study the prevalence of myopia in all Russian regions and develop preventive programs to control myopia in children.

The Prevalence of Myopia in Schoolchildren in Some Regions of Russia

The frequency of myopia reached 26 % among of school graduates in 2000. In case of graduates from gymnasiums and lyceums — 50 %. The share of severe form of myopia 10–12 %. A pilot study was conducted. The prevalence of myopia was estimated in schoolchildren of 1, 5 and 11 classes in some Russian regions (Moscow, St. Petersburg, Igevsk, Ivanovo). Objectively cycloplegic refraction was studied in 3659 schoolchildren. During the entire period of being at school emmetropia was the most common type of refraction. In 5 and 11 classes myopia was more often refractive errors. The prevalence of myopia among 1th classes schoolchildren was 2.4 %, among 5th classes — 19.7 %, 11th classes — 38.6 %. In children studying in lyceums the prevalence of myopia was significantly higher (p < 0.01). Already in the 1 classes of gymnasiums and lyceums myopic children were 7.5 %, while in regular schools only 1.4 %. In 11 classes of lyceums the share of myopic children was 50.7%, in regular schools it was 30.9 %. This confirms the influence of education on the prevalence of myopia as an additive factor. The study of the myopia prevalence should be continued in different regions and municipalities to the subsequent development the rational programs for prevention of development and the progression of myopia in school.

Rola aktywności zewnętrznej w rozwoju krótkowzroczności u dzieci w wieku szkolnym

The aim of our study was to examine whether outdoor activity influences the prevalence of myopia in schoolchildren. 5601 Polish students of elementary and secondary schools (2688 boys and 2913 girls), 6–18 years of age (mean 11.9 ±3.2 years) were examined. In every student cycloplegia after 1% tropicamide was performed. The mean spherical equivalent (SE) was calculated after examination of both eyes. Time spent on outdoor activity was evaluated based on a questionnaire. The obtained results were typed into an Excel spreadsheet and analyzed statistically using Statistica 10 software. Non-parametric tests were used due to the SE distribution being significantly different from normal distribution in the Kolmogorov–Smirnov test. The Spearman rank correlation coefficient (Rs) was used to evaluate the strength of the correlation between these variables. A p-value less than 0.05 was considered significant. It has been established that with the increase in time spent on outdoor activity, the spherical equivalent of the examined students significantly increases, but the correlation is very weak (Rs = +0.036, p = 0.007). Outdoor activity slightly reduces the prevalence of myopia in schoolchildren.

Myopia in schoolchildren in a rural community in the State of Mexico, Mexico.

PurposeThis study sought to determine the prevalence of myopia in schoolchildren of a rural population in Mexico.MethodsA cross-sectional study was conducted in 317 children between 6 and 12 years old. A complete refractive examination was performed, including static retinoscopy without cycloplegic agents. All procedures were conducted according to the Declaration of Helsinki.ResultsIn total, 9.7% (95% CI: 13.07–6.52) of the examined children were myopic (spherical equivalent ≤ −0.50 D), 4.4% (95% CI: 6.66–2.14) presented astigmatism (cylinder ≤ −1.50 D), and 5.4% (95% CI: 7.89–2.91) presented hyperopia (spherical equivalent ≥ +0.50 D).ConclusionAdditional research is required to assess the prevalence of refractive errors in rural areas in Mexico, to analyze the associated risk factors, and to implement appropriate eye care plans for this population.

Prevalence of myopia in schoolchildren in Ejina: the Gobi Desert Children Eye Study.

To determine the prevalence and associations of myopia in schoolchildren in provincial Western China. In the school-based observational cross-sectional Gobi Desert Children Eye Study, cylcoplegic refractometry as part of a comprehensive ophthalmic examination was performed in all schools in the oasis region of Ejina. Out of 1911 eligible children, 1565 (81.9%) children with a mean age of 11.9 ± 3.5 years (range, 6-21 years) participated. The mean refractive error in the worse eye was -1.38 ± 2.04 diopters (D) (median, -0.88 D; range, -13.00 to +6.50 D). In multivariate analysis, more myopic refractive errors were associated with older age (P < 0.001; regression coefficient B: -0.26; 95% confidence interval [CI]: -0.28, -0.23), female sex (P = 0.005; B: -0.26; 95%CI: -0.43, -0.08), more myopic paternal refractive errors (P < 0.001; B: 0.20; 95%CI: 0.14, 0.27), more myopic maternal refractive errors (P < 0.001; B: 0.18; 95%CI: 0.12, 0.24), and fewer hours spent outdoors (P = 0.038; B: 0.18; 95%CI: 0.01, 0.35). The prevalence of myopia, defined as refractive errors (spherical equivalent) of ≤-0.50, ≤-1.00, and ≤-6.00 D in the worse eye, was 60.0 ± 1.2%, 48.0 ± 1.3%, and 2.9 ± 0.4%, respectively. The prevalence of high myopia (≤-6.00 D) was 2.9 ± 0.4% in the whole study population, and it was 9.9 ± 3.0% in 17-year-olds. It was not associated with time spent outdoors (P = 0.66). Even in Western China, prevalence of myopia in schoolchildren is high. As in East China, low and medium myopia was associated with less time spent outdoors. High myopia was not significantly associated with outdoors time. Compared with the myopia prevalence in elderly Chinese populations, the relatively high myopia prevalence in schoolchildren in China predicts a marked increase in vision-threatening high myopia in future elderly populations in China.

Prevalence of refractive errors among school children in Northeastern Iran

To determine the prevalence of refractive errors among schoolchildren in Northeastern Iran by age and gender. Using multistage random cluster sampling, 2020 schoolchildren 6-17 years of age were selected for this cross-sectional study. The participants totalled 1551 (response rate 76.8%) elementary and junior high school children (41.5% boys and 58.5% girls) from the northeast of Iran. Cycloplegic autorefraction was used to determine refractive error. Myopia was defined as a spherical equivalent (SE) of -0.50 dioptre (D) or worse, hyperopia as a SE of +2.00 D or more, and astigmatism as cylinder equal to or worse than -0.75 D. The prevalence of uncorrected, habitual and optimal visual acuity of 6/12 (0.30 logMAR) or worse in the better eye was 2.2%, 1.0%, and 0.2% respectively. The prevalence rates of myopia, hyperopia and astigmatism were 4.3% (95%CI: 3.3-5.3), 5.4% (95%CI: 4.3-6.5) and 11.5% (95%CI: 9.9-13.1) respectively and were not related to gender. The prevalence of myopia and against-the-rule astigmatism increased significantly with age (p < 0.0001). The prevalence of hyperopia significantly decreased with age (p < 0.0001). The prevalence of myopia in schoolchildren in Northeastern Iran is considerably lower than that of East Asian populations, but similar to many other populations, including South Africa, Chile and other countries of the Middle East. Whilst comparisons with other studies show that the prevalence of hyperopia and astigmatism in Northeastern Iran is higher than that of some countries, it is lower compared with others.

Prevalence and risk factors of refractive errors among schoolchildren in Bojnourd, Iran

Abstract Purpose To determine the prevalence and risk factors of refractive errors among schoolchildren in Bojnourd, Iran. Methods In a cross‐sectional study using random cluster sampling, 2020 schoolchildren 6 to 17 years of age were selected in this study. The participants totaled 1551; 643 boys and 908 girls of the elementary and middle schoolchildren of Bojnourd, northeast of Iran. Mean age of the participants was 11.2 years (response rate=76.7%). Refractive errors were measured under cycloplegia. Myopia defined as spherical equivalent (SE) refraction ‐ 0.5 dioptre (D) or worse, hyperopia as SE +2.00 D or more, and astigmatism as cylinder ‐0.75 D or worse. Results The prevalence of myopia, hyperopia and astigmatism were 4.3%, 5.4% and 11.5% respectively and were not related to the gender. The prevalence of myopia and against‐the‐rule astigmatism increased with age (p&lt;0.001). Conclusion The results of this study showed that the prevalence of myopia in schoolchildren of Bojnourd was similar to that in most places excluding East Asian countries, and that of hyperopia and astigmatism were in the mid range.