[Forcasting the prevalence of myopia among students aged 6-18 years in China from 2021 to 2030]

Associations of 24-hour movement behaviors with externalizing and internalizing problems among children and adolescents prescribed with eyeglasses/contact lenses

Background

Emerging evidence points towards the psychological benefits of meeting 24-hour movement behavior (24-HMB) guidelines, but such associations have not yet been investigated among children and adolescents of prescribed eyeglasses/contact lenses. To this end, we examined associations of meeting 24-HMB guidelines with internalizing and externalizing challenges in this population.

Methods

We used data from the 2021 National Survey of Children's Health, a cross-sectional survey including a representative sample of US children and adolescents. Data on movement behaviors (physical activity [PA], sedentary behavior operationalized via screen time [ST], and sleep duration [SL]) and internalizing and externalizing problems were collected through caregiver proxy reports. Caregivers completed questionnaires for 6030 (2799 girls) US children and adolescents of prescribed eyeglasses/contact lenses. Logistic regression analyses were conducted to determine the above-presented associations.

Results

Only 7.1 % of those prescribed eyeglasses/contact lenses met all three 24-HMB guidelines, while they were more likely to meet SL guideline alone (32.1 %) in relation to other independent guidelines including PA (2.5 %) and ST (10.9 %). Compared to not meeting any of the three 24-HMB guidelines, meeting at least two guidelines (25.22 %) was significantly linked to lower odds of internalizing problems and externalizing problems.

Conclusion

Meeting at least two components of the 24-HMB guidelines was beneficially linked to internalizing and externalizing problems. Thus, strategies or intervention programs that focus on meeting 24-HMB guidelines should be implemented among children and adolescents of those prescribed eyeglasses/contact lenses to foster coping with psychological issues.

Association between body stature and prevalence of reduced visual acuity in high school graduates in Hangzhou, China

CLINICAL RELEVANCE

The association between myopia and body stature is of great significance for understanding prevention and control of myopia. It has been extensively studied in previous studies but without consistent conclusions.

BACKGROUND

The aim of this study is to investigate the association between body stature and prevalence of reduced visual acuity in high school graduates in Hangzhou, China.

METHODS

50,620 high school graduates who finished the physical examination of the national college entrance examination in 2020 were included. Data were derived from the database of physical examination of the national college entrance examination. Height and weight were measured, and body mass index (BMI) was calculated according to the general formula. Visual acuity was measured by the standard logarithmic visual acuity chart.

RESULTS

The prevalence of reduced visual acuity was 90.38% in high school graduates. Girls had a higher prevalence of reduced visual acuity than boys (93.07% vs 87.60%, P < 0.001). Boys with normal visual acuity were significantly taller (P < 0.001) and heavier (P < 0.001) than those with reduced visual acuity. Girls with normal visual acuity were significantly taller than those with reduced visual acuity (P < 0.001). The prevalence of reduced visual acuity was significantly inversely associated with height in both boys (P < 0.001) and girls (P < 0.001). The risk of reduced visual acuity was the lowest in the fourth quartile of height. The prevalence of reduced visual acuity was significantly associated with BMI only in boys (P < 0.001). The risk of reduced visual acuity was the lowest in the third quartile of BMI.

CONCLUSIONS

The prevalence of reduced visual acuity was inversely associated with height in both boys and girls, and there was a U-shaped association with BMI only in boys.

Effects of air pollution on myopia: an update on clinical evidence and biological mechanisms

Myopia is one of the most common forms of refractive eye disease and considered as a worldwide pandemic experienced by half of the global population by 2050. During the past several decades, myopia has become a leading cause of visual impairment, whereas several factors are believed to be associated with its occurrence and development. In terms of environmental factors, air pollution has gained more attention in recent years, as exposure to ambient air pollution seems to increase peripheral hyperopia defocus, affect the dopamine pathways, and cause retinal ischemia. In this review, we highlight epidemiological evidence and potential biological mechanisms that may link exposure to air pollutants to myopia. A thorough understanding of these mechanisms is a key for establishing and implementing targeting strategies. Regulatory efforts to control air pollution through effective policies and limit individual exposure to preventable risks are required in reducing this global public health burden.

A Latent Class Analysis of Student Eye Care Behavior: Evidence From a Sample of 6–17 Years Old in China

Purpose

To understand the latent classes and distribution of an adolescent eye care behavior, and to provide a basis for the formulation of appropriate adolescent vision health management interventions.

Methods

Information on eye behavior and eye health of primary and secondary school students in Wuhan was collected by multistage stratified cluster sampling. The latent class analysis (LCA) method was used to analyze the students' eye care behavior, and the latent class model (LCM) was built.

Results

A total of 6,130 students were enrolled in this study, of which 53.56% were males, aged from 6 to 17 years old, with an average age of 10.33 ± 2.60. The latent class results classified the adolescents' eye care behaviors into bad behaviors, moderate behaviors, and healthy behaviors. The model fitting results were as follows: Akaike Information Criterion (AIC) was 36,698.216, Bayesian Information Criterion (BIC) was 36,906.565, Adjusted Bayesian Information Criterion (aBIC) was 36,808.056, and entropy was 0.838.Compared with the healthy behaviors class, the bad behaviors class was more prevalent in high schools (p = 0.003), non-demonstration schools (p = 0.001), and most of this group had astigmatism (p = 0.002). The moderate behaviors class predominately consisted of females (p = 0.001), 15–17 years old (p = 0.005, 6~8 years old as the reference), from non-demonstration schools (p < 0.001), and most had myopia (p = 0.009).

Conclusion

There were differences in basic demographic characteristics, visual acuity development level, and family visual environment among different classes. In the management and intervention of an adolescent vision health, we should continue to promote the visual health management of adolescents based on visual monitoring and realize the early intervention and guidance of individuals in bad behaviors class.

Beijing Pinggu Childhood Eye Study: The Baseline Refractive Characteristics in 6- to 12-Year-Old Chinese Primary School Students

Purpose

To report the design and baseline data of a 3-year cohort study in Beijing Pinggu District primary school students in China after COVID-19.

Methods

Noncycloplegic and cycloplegic spherical equivalent refraction (SER) were measured, ocular biometry, including the axial length (AL), anterior chamber depth (ACD) and corneal power (CP), were collected before cycloplegia. Corneal radius (CR), AL-to-CR ratio, and lens power (LP) were calculated.

Results

Among the 4,806 (89.1%) eligible students (51.5% male), the prevalence of emmetropia, myopia, mild hyperopia, and mild-to-high hyperopia was 12.8, 30.8, 53.0, and 3.3% after cycloplegia, respectively. Myopia increased from 2.5% in 6- to 71.6% in 12-year-old students, with 9- and 10-year-olds showing the most prominent increases. The median of cycloplegic SER was 0.50 (IQR = 1.63), and the noncycloplegic SER was −0.38 D (IQR = 1.50), which is more negative than the cycloplegic refraction. The mean AL increased with age, from 22.46 ± 0.70 mm to 24.26 ± 1.07 mm. The ACD increased from 3.38 ± 0.28 mm to 3.70 ± 0.30 mm, and the AL-to-CR ratio increased from 2.91 ± 0.08 to 3.12 ± 0.13 between 6- and 12-year-old students. AL, CR and LP explained the SER variance with R² of 86.4% after adjusting the age and gender.

Conclusions and Relevance

The myopia prevalence since emergence of COVID-19 rapidly increased from 6- to 12-year primary school Chinese children, especially after 7 years of age. The non-cycloplegia SER overestimated the prevalence of myopia, and the cycloplegic SER is a more accurate and reliable method to assess the prevalence of refractive status.

Trends in Myopia Development Among Primary and Secondary School Students During the COVID-19 Pandemic: A Large-Scale Cross-Sectional Study

Objectives

To evaluate myopia development among primary and secondary school students during the coronavirus 2019 (COVID-19) pandemic.

Methods

A cross-sectional study was conducted to evaluate the development of myopia among students in Shenzhen, China during the COVID-19 outbreak.

Results

The study included 1,472,957 and 1,573,824 students in 2019 and 2020, respectively. The prevalence of myopia was 46.9 and 50.5% in 2019 and 2020, respectively. The prevalence of myopia among students in the former Shenzhen Special Economic Zone (SEZ) was higher than that in areas outside the former Shenzhen SEZ (2019: 47.0 vs. 43.7%; 2020: 50.5 vs. 47.3%). The prevalence of myopia among girls was higher than that among boys (2019: 50.4 vs. 44.0%; 2020: 54.0 vs. 47.6%). The 50th percentile (P50) of spherical equivalent refraction (SER) in the right eye among girls was lower than that in boys. The prevalence of myopia continued to increase as the grade increased, with the greatest annual increase observed in Grades 2–5 (3.4–3.9%). The P50 of SER in the right eye of students decreased as the grade increased.

Conclusions

The prevalence of myopia among students increased during the COVID-19 pandemic, especially in primary school Grades 2–5.