Temporal and spatial characterization of myopia in China

Gender Difference of the Association Between Sleep Duration and Myopia Among Children and Adolescents

Purpose

With girls typically exhibiting higher rates of myopia than boys, however, the mechanisms behind this gender difference remain unclear. This study aims to investigate the gender disparities in the relationship between myopia, sleep duration, physical activity, and BMI.

Patients and Methods

A total of 3138 primary and secondary school students were included. Mplus 8.3 was used to perform the multiple mediation analysis.

Results

Sleep duration was indicated to directly affect myopia (β=0.273, 95% CI=0.184-0.356) and through physical activity, BMI, physical activity and BMI three significantly mediation pathways, respectively. In terms of gender, the mediating direct effect of sleep duration on myopia of boys was 66.96%, which is much higher than that of girls' 50.91%. And the mediating indirect effect of sleep duration on myopia through physical activity and BMI are 32.65% and 12.10% respectively among girls, both of which are significantly higher than that of boys.

Conclusion

The study found that there are significant differences in the impact of sleep duration on myopia in children and adolescents of different genders. In this regard, while paying attention to the sleep duration of children and adolescents, special attention should also be paid to the indirect impact of girls' physical activity and BMI on myopia, and targeted measures should be formulated according to children of different genders to effectively protect the eye health of children and adolescents.

Spatial epidemiological characteristics and driving factors of myopia among school-age children based on geographical detector: a national study

The present study aimed to examine the spatial characteristics of myopia and identify the socioeconomic and environmental factors influencing its prevalence. Myopia prevalence among children of school age of Han ethnicity in China was 56.6% in 2019, with the highest and lowest prevalence's in Shandong (66.8%) and Guizhou (47.3%), respectively. There was a spatial aggregation of myopia prevalence in China. Environmental factors (atmospheric PM2.5 concentration and forest coverage) and socioeconomic factors (gross domestic product per capita, per capita disposable income, hospital beds per thousand people, and Engel coefficient) have significant influences on myopia prevalence. The interaction of each factor on myopia showed nonlinear enhancement. Myopia prevalence among children of school age was spatially clustered, and environmental and socioeconomic conditions are associated with myopia prevalence. Our findings provide novel perspectives for the comprehensive prevention and control of myopia.

Regional disparities in the prevalence and correlated factors of myopia in children and adolescents in Gansu, China

Background

Myopia is a significant public health problem across the globe. This study aimed to examine the regional disparity in prevalence and correlated factors of myopia in children and adolescents in two typical regions, Gannan Tibetan Autonomous Prefecture (Gannan Prefecture for short, a Tibetan residential area) and Wuwei City (a Han residential area) in Gansu Province, China, and to provide a reference for the prevention and control of regional myopia.

Methods

The study was a cross-sectional study of children and adolescents in Gansu Province, China. A total of 6,187 (Wuwei City: 3,266, Gannan Tibetan Autonomous Prefecture: 2,921) students were selected by stratified cluster sampling. Eye examinations and questionnaires were administered to the participants. Myopia is defined as a condition in which the spherical equivalent refractive error of an eye is less than or equal to -0.50 D when ocular accommodation is relaxed. The χ2 test and multivariate logistic regression analysis were used to analyze the correlated factors of myopia.

Results

The myopia rate of 6,187 students was 71.4%, and students had a higher rate of myopia (77.5%) in Wuwei City compared to Gannan Prefecture (64.6%) (p < 0.001). The results of multivariate analysis in Wuwei City showed that girls (odds ratio (OR) = 1.325), junior students (OR = 2.542), senior students(OR = 4.605), distance between eyes and book less than one foot (OR = 1.291), and parents with myopia (one, OR = 2.437; two, OR = 4.453) had higher risks of myopia (all, p < 0.05). For Gannan Prefecture, girls (OR = 1.477), senior students (OR = 1.537), daily time spent doing homework ≥2 h (OR = 1.420), the distance between eyes and book less than one foot (OR = 1.205), mean time continuous eye use (0.25-<0.5 h, OR = 1.345, 0.5-<1 h, OR = 1.317, ≥1 h, OR = 1.313), average daily sleep duration <8 h (OR = 1.399), and parents with myopia (one, OR = 1.852; two, OR = 2.913) had higher risks of myopia (all, p < 0.05).

Conclusion

The prevalence of myopia is at a relatively high level in Gansu Province. The prevalence and risk factors for myopia vary by region.

Epidemiological variations and trends in glaucoma burden in the Belt and Road countries

BACKGROUND

Analyzing the glaucoma burden in "Belt and Road" (B&R) countries based on age, gender, and risk factors from 1990 to 2019 in order to provide evidence for future prevention strategies.

METHODS

We applied global burden of disease(GBD) 2019 to compare glaucoma prevalence and Years lived with disabilities (YLDs) from 1990 to 2019 in the B&R countries. Trends of disease burden between 1990 and 2019 were evaluated using the average annual percent change and the 95% uncertainty interval (UI) were reported.

RESULTS

From 1990 to 2019, most B&R countries showed a downward trend in age-standardized prevalence and YLDs (all P < 0.05). Additionally, only the age-standardized YLDs in males of Pakistan has a 0.35% increase (95%CI:0.19,0.50,P < 0.001), and most B&R countries has a decline(all P < 0.05) in age-standardized YLDs in every 5 years age group after 45 years old except for Pakistan(45-79 years and > 85 years), Malaysia(75-84 years), Brunei Darussalam(45-49 years), Afghanistan(70-79 years). Finally, in all Central Asian countries, the age-standardized YLDs due to glaucoma caused by fasting hyperglycemia demonstrated have an increase between 1990 and 2019 (all P < 0.05), but Armenia and Mongolia have a decrease between 2010 and 2019 (all P < 0.05).

CONCLUSION

The prevalence of glaucoma continues to pose a significant burden across regions, ages, and genders in countries along the "B&R". It is imperative for the "B&R" nations to enhance health cooperation in order to collaboratively tackle the challenges associated with glaucoma.

Assessment of dynamic corneal response parameters in Chinese patients of different ages with myopia and orthokeratology lenses using the Corvis ST

OBJECTIVE

To investigate the effects of orthokeratology lenses (OK lenses) on corneal biomechanics in subjects of different ages.

METHODS

Fifty subjects with mild to moderate myopia were categorized into three groups (Group I-III) based on their age. Corvis ST was used to collect dynamic corneal response parameters (DCRs) at different follow-up time points. Repeated measures analysis of variance combined with simple effect analysis was used to analyze the changes in DCRs in different groups during the follow-up period. Multiple linear regression analysis was used to analyze the correlations between axial length growth (ALG) at 6 months (ALG-6M) or 12 months (ALG-12M) and sex, baseline spherical equivalent refraction (SER), and DCRs.

RESULTS

The DCRs changed in all three groups after wearing OK lenses. Most DCRs showed significant differences between baseline and 6 months after wearing OK lenses, while the differences between DCRs at 6 months and 12 months were not statistically significant. No significant differences in DCRs were observed among the three groups at the same follow-up time point. Additionally, at 6 months post-OK lens wear, ALG-6M was significantly correlated with velocity of the corneal apex at the first applanation (A1V-6M) (P = 0.002), Corvis biomechanical index (CBI-6M) (P = 0.004), the maximum amount of corneal movement (DAM-6M) (P = 0.010), deformation amplitude ratio of 2 mm (DAR2-6M) (P = 0.010), and stress-strain index (SSI-6M) (P = 0.038) in Group I. Furthermore, ALG-12M showed significant correlations with SSI-6M (P = 0.031), peak distance at the DAM (PD)-6M (P = 0.037), baseline Ambrósio Relational Thickness to the horizontal profile (P = 0.013) in Group I.

CONCLUSIONS

The majority of DCRs displayed significant changes within the initial 6 months of OK lens wear. Minimal variation in DCRs was observed across different age groups at the same follow-up time point. Certain DCR parameters exhibited correlations with ALG, suggesting their potential in predicting ALG in myopic children undergoing OK lenses correction.

Initiation of China Alliance of Research in High Myopia (CHARM): protocol for an AI-based multimodal high myopia research biobank

INTRODUCTION

High myopia is a pressing public health concern due to its increasing prevalence, younger trend and the high risk of blindness, particularly in East Asian countries, including China. The China Alliance of Research in High Myopia (CHARM) is a newly established consortium that includes more than 100 hospitals and institutions participating across the nation, aiming to promote collaboration and data sharing in the field of high myopia screening, classification, diagnosis and therapeutic development.

METHODS AND ANALYSIS

The CHARM project is an ongoing study, and its initiation is distinguished by its unprecedented scale, encompassing plans to involve over 100 000 Chinese patients. This initiative stands out not only for its extensive scope but also for its innovative application of artificial intelligence (AI) to assist in diagnosis and treatment decisions. The CHARM project has been carried out using a 'three-step' strategy. The first step involves the collection of basic information, refraction, axial length and fundus photographs from participants with high myopia. In the second step, we will collect multimodal imaging data to expand the scope of clinical information, for example, optical coherence tomography and ultra-widefield fundus images. In the final step, genetic testing will be conducted by incorporating patient family histories and blood samples. The majority of data collected by CHARM is in the form of images that will be used to detect and predict the progression of high myopia through the identification and quantification of biomarkers such as fundus tessellation, optic nerve head and vascular parameters.

ETHICS AND DISSEMINATION

The study has received approval from the Ethics Committee of Beijing Tongren Hospital (TREC2022-KY045). The establishment of CHARM represents an opportunity to create a collaborative platform for myopia experts and facilitate the dissemination of research findings to the global community through peer-reviewed publications and conference presentations. These insights can inform clinical decision-making and contribute to the development of new treatment modalities that may benefit patients worldwide.

TRIAL REGISTRATION NUMBER

ChiCTR2300071219.

The Effects of Spectacles or Orthokeratology on the Tear Film in Children and Adolescents

INTRODUCTION

Myopia prevalence among adolescents is increasing annually. While orthokeratology (OK) is effective for controlling myopia progression, it may also be detrimental. We investigated tear film parameters [including tear mucin 5AC (MUC5AC) concentration] in children and adolescents with myopia treated with spectacles or OK compared with those with emmetropia.

METHODS

This prospective case-control study enrolled children (aged 8-12 years; 29 and 39 with myopia treated with OK and spectacles, respectively, and 25 with emmetropia) and adolescents (aged 13-18 years; 38 and 30 with myopia treated with OK and spectacles, respectively, and 18 with emmetropia). We recorded the ocular surface disease index (OSDI), visual analog scale (VAS) score, tear meniscus height (TMH), noninvasive tear breakup time (NIBUT), meibomian gland score (meiboscore), ocular redness score, and tear MUC5AC concentration in the emmetropia, spectacle (after 12 months of spectacle wearing), and OK (baseline, and after 1-, 3-, 6-, and 12-month use) groups. We observed changes from baseline to 12 months in the OK group and compared parameters among the spectacle, 12-month OK, and emmetropia groups.

RESULTS

The 12-month OK group differed significantly from the spectacle and emmetropia groups in most indicators among children and adolescents (P < 0.05). Differences were not noticeable between the spectacle and emmetropia groups (only PVAS < 0.05 among the children). In the OK group, the 12-month NIBUT was significantly decreased (P < 0.05) in both age groups; the upper meiboscore was increased at 6 and 12 months (both P < 0.05) among children; ocular redness scores were higher at 12 months than at baseline (P = 0.007), 1 month (P < 0.001), and 3 months (P = 0.007) among children; and the MUC5AC concentration was decreased at 6 and 12 months among adolescents, but only at 12 months among children (all P < 0.05).

CONCLUSIONS

Long-term OK can negatively influence the tear film in children and adolescents. Moreover, changes are masked by spectacle wearing.

TRIAL REGISTRATION

This trial is registered with "ChiCTR2100049384."

Baseline metrics that may predict future myopia in young children

PURPOSE

We used baseline data from the PICNIC longitudinal study to investigate structural, functional, behavioural and heritable metrics that may predict future myopia in young children.

METHODS

Cycloplegic refractive error (M) and optical biometry were obtained in 97 young children with functional emmetropia. Children were classified as high risk (HR) or low risk (LR) for myopia based on parental myopia and M. Other metrics included axial length (AXL), axial length/corneal radius (AXL/CR) and refractive centile curves.

RESULTS

Based on the PICNIC criteria, 46 children (26 female) were classified as HR (M = +0.62 ± 0.44 D, AXL = 22.80 ± 0.64 mm) and 51 (27 female) as LR (M = +1.26 ± 0.44 D, AXL = 22.77 ± 0.77 mm). Based on centiles, 49 children were HR, with moderate agreement compared with the PICNIC classification (k = 0.65, p < 0.01). ANCOVA with age as a covariate showed a significant effect for AXL (p < 0.01), with longer AXL and deeper anterior chamber depth (ACD) (p = 0.01) in those at HR (differences AXL = 0.16 mm, ACD = 0.13 mm). Linear regression models showed that central corneal thickness (CCT), ACD, posterior vitreous depth (PVD) (=AXL - CCT - ACD-lens thickness (LT)), corneal radius (CR) and age significantly predicted M (R = 0.64, p < 0.01). Each 1.00 D decrease in hyperopia was associated with a 0.97 mm elongation in PVD and 0.43 mm increase in CR. The ratio AXL/CR significantly predicted M (R = -0.45, p < 0.01), as did AXL (R = -0.25, p = 0.01), although to a lesser extent.

CONCLUSIONS

Although M and AXL were highly correlated, the classification of pre-myopic children into HR or LR was significantly different when using each parameter, with AXL/CR being the most predictive metric. At the end of the longitudinal study, we will be able to assess the predictability of each metric.

Effects of exogenous retinoic acid on ocular parameters in Guinea pigs with form deprivation myopia

Aim: Myopia is a common chronic eye disease, this study is to investigate the effects of exogenous retinoic acid (RA) on intraocular parameters, especially choroidal thickness (CT) and retinal thickness (RT), in guinea pigs with form deprivation myopia (FDM).

Methods: A total of 80 male guinea pigs were divided randomly into 4 groups: Control, FDM, FDM + RA, and FDM + Citral groups. The FDM + RA group was given 24 mg/kg RA dissolved in 0.4 mL peanut oil; the FDM + Citral group was given citral 445 mg/kg dissolved in 0.4 mL peanut oil; The other two groups were given 0.4 mL peanut oil. After 4 weeks, the refractive error (RE), axial length (AL), and intraocular pressure (IOP) of all guinea pigs were measured, and the parameters of RT and CT were obtained using enhanced depth imaging optical coherence tomography (EDI-OCT).

Results: After 4 weeks, both the RE and AL in the FDM and FDM + RA groups were increased, and the RT and CT in both groups were smaller than those in the Control group (p &lt; 0.05). Only the IOP of the right eye in the FDM + RA group increased significantly (p &lt; 0.05). The RT of the right eye of the 4 groups was compared: Control group &gt; FDM + Citral group &gt; FDM group &gt; FDM + RA group. Compared with the RT of the left eye and the right eye among the 4 groups, the RT of the right eye in the FDM and FDM + RA groups was significantly less than that in the left eye (p &lt; 0.05). Moreover, the CT of the right eye in the Control group was greater than that in the other three groups (p &lt; 0.0001). There was no significant difference in the CT among the FDM, FDM + RA, and FDM + Citral groups (p &gt; 0.05). In contrast to the RT results, the CT results of the left and right eyes in the FDM + Citral group showed statistically significant differences (p &lt; 0.05).

Conclusion: RA participates in the progression of FDM as a regulatory factor. Exogenous RA can increase the RE, AL, and IOP of FDM guinea pigs, and might aggravate the retinal thinning of FDM guinea pigs. Citral can inhibit these changes, but RA might not affect the thickness of the choroid.

Global, Regional, and National Burdens of Blindness and Vision Loss in Children and Adolescents from 1990 to 2019: A Trend Analysis

PURPOSE

To provide estimates for regional and national burdens of blindness and vision loss among children and adolescents between 1990 and 2019 by disease, age, and sociodemographic index (SDI).

DESIGN

This was a retrospective demographic analysis based on aggregated data.

METHODS

This was a population-based study using 1990-2019 data on the burden of vision loss and blindness from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. The burden of vision loss and blindness was evaluated in terms of case numbers, rates per 100 000 population, and average annual percentage changes (AAPCs) in prevalence rates and years lived with disability (YLDs).

RESULTS

Globally, the rates of blindness and vision loss per 100 000 population decreased in all age groups between 1990 and 2019, with prevalence rates decreasing from 1091.4 (95% uncertainty interval [UI], 895.2-1326.1) to 1036.9 (95% UI, 847.8-1265.9, AAPC, -0.2) and YLDs decreasing from 44.5 (95% UI, 28.1-66.5) to 40.2 (95% UI, 25.1-60.7, AAPC, -0.4). Most of these reductions in prevalence rates (AAPC, -0.2, 95% confidence interval [CI], -0.2 to -0.1) and YLDs (AAPC, -0.2, 95% CI, -0.3 to -0.2) were due to decreases in refractive disorder. Notably, near-vision loss prevalence (AAPC, 0.3, 95% CI, 0.2-0.4) and YLDs (AAPC, 0.3, 95% CI, 0.2-0.4) substantially increased in all age groups. Children and adolescents in low- and low-middle SDI countries exhibited substantial decreases in the prevalence rates and YLDs of blindness and vision loss, but their counterparts in high- and middle-high SDI countries experienced a substantial increase in prevalence.

CONCLUSIONS

Globally, efforts in the past 3 decades have substantially decreased the burdens of blindness and vision loss among children and adolescents. However, there is extensive variation according to the kind of impairment, age group, and country SDI.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Efficacy of a Deep Learning System for Screening Myopic Maculopathy Based on Color Fundus Photographs

INTRODUCTION

The maculopathy in highly myopic eyes is complex. Its clinical diagnosis is a huge workload and subjective. To simply and quickly classify pathologic myopia (PM), a deep learning algorithm was developed and assessed to screen myopic maculopathy lesions based on color fundus photographs.

METHODS

This study included 10,347 ocular fundus photographs from 7606 participants. Of these photographs, 8210 were used for training and validation, and 2137 for external testing. A deep learning algorithm was trained, validated, and externally tested to screen myopic maculopathy which was classified into four categories: normal or mild tessellated fundus, severe tessellated fundus, early-stage PM, and advanced-stage PM. The area under the precision-recall curve, the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, accuracy, and Cohen's kappa were calculated and compared with those of retina specialists.

RESULTS

In the validation data set, the model detected normal or mild tessellated fundus, severe tessellated fundus, early-stage PM, and advanced-stage PM with AUCs of 0.98, 0.95, 0.99, and 1.00, respectively; while in the external-testing data set of 2137 photographs, the model had AUCs of 0.99, 0.96, 0.98, and 1.00, respectively.

CONCLUSIONS

We developed a deep learning model for detection and classification of myopic maculopathy based on fundus photographs. Our model achieved high sensitivities, specificities, and reliable Cohen's kappa, compared with those of attending ophthalmologists.