Is the Change in Prevalence of High Myopia Compared to That of Myopia Really Disproportionate?

Purpose: It has been noted that, at higher prevalences, the rate of change in the prevalence of high myopia seems to be disproportionately greater compared with the rate of change in the prevalence of myopia. A simple, evidence-based explanation for this relationship is offered. Methods: Using a convenience sample of 41 datasets with prevalence estimates for at least two refractive error thresholds (e.g., -0.50 and -6.00 D) the common slope of the logit vs. refractive threshold was applied to model expected rates of high myopia across the myopia prevalence range and the corresponding ratio of change in high myopia to myopia prevalence. Results: The logit of high myopia is related linearly to the logit of myopia. The ratio of increase in high myopia prevalence to that for myopia prevalence increases with underlying prevalence. For example, an increase in myopia prevalence from 19% to 20% is modelled to be accompanied by a 0.1% increase in the prevalence of high myopia from 1.55% to 1.65%-a ratio of 0.1. Conversely, an increase in myopia prevalence from 79% to 80% is predicted to result in a 1% increase in the prevalence of high myopia from 20.6% to 21.6%-a ratio of 1.0. Conclusions: The increase in the prevalence of high myopia compared with that of myopia as the latter increases is merely a function of the underlying nature of refractive error probability distributions and requires no further investigation as to its origin. Translational Relevance: This study shows how the prevalence of myopia and high myopia are inter-related. A widespread effort to slow myopia progression will affect the prevalence of high myopia but not myopia in general. In contrast, efforts to delay myopia onset will affect both.

Epidemiology of Myopia: Prevalence, Risk Factors and Effects of Myopia. / Epidemiologie der Myopie: Prävalenz, Risikofaktoren und Auswirkungen der Myopie.

Myopia is the most common cause of visual impairment in children and young adults. In order to assess the consequences for society, it is necessary to know temporal trends in prevalence, incidence and associated factors in childhood and adolescence, as well as the rate of myopia progression, as based on epidemiological research. This paper presents a literature review of publications from 2020 up to March 2024, supplemented by other relevant publications. The prevalence of myopia in children and adolescents in Germany is almost stable and is significantly lower than in Asia. The development of myopia is influenced by outdoor activity, parental myopia, genetics and near work, while insufficient time spent outdoors in childhood is a significant and controllable risk factor for myopia-related complications such as myopic maculopathy, glaucoma, and retinal detachment.

[An epidemiological survey of visual impairment in rural populations aged 30 and above: the Handan Eye Study].

Objective: To investigate the changes in prevalence and causes of blindness and visual impairment over six years among rural populations aged 30 and above in Yongnian County, Handan City, Hebei Province, a pilot area in northern China for blindness prevention and treatment, and to study the incidence of common blinding eye diseases. Methods: This population-based prospective cohort study included a baseline survey conducted from 2006 to 2007 using stratified cluster sampling, targeting 6 830 Han Chinese individuals aged 30 and above, with a response rate of 90.4%, and a follow-up survey conducted from 2012 to 2013 with 5 394 participants, maintaining a response rate of 85.3%. Visual impairment was defined according to World Health Organization standards as visual acuity<20/60 but ≥20/400, and blindness as visual acuity<20/400. Age-and gender-standardized prevalence rates of blindness and visual impairment, along with their 95% confidence intervals (CI), were estimated. The six-year incidence rates of primary glaucoma, age-related macular degeneration, and myopic maculopathy, along with their 95%CI, were reported. Results: At baseline, the standardized prevalence of bilateral blindness in individuals aged 30 and above was 0.6% (41/6 799) for presenting visual acuity and 0.5% (31/6 799) for best-corrected visual acuity. These rates were higher than those found in the follow-up survey, 0.5% (27/5 293) and 0.3% (17/5 276). Conversely, the standardized prevalence of bilateral visual impairment increased from 4.7% (361/6 799) and 1.0% (85/6 799) at baseline to 6.5% (355/5 293) and 1.4% (74/5 276) at follow-up, respectively. The leading cause of bilateral blindness was cataract in both baseline (13/31, 41.9%) and follow-up (7/17) surveys. Other major causes included myopic retinal degeneration (5/31, 16.1% at baseline; 2/17 at follow-up), glaucoma (3/31, 9.7% at baseline; 2/17 at follow-up), and corneal opacity (3/31, 9.7% at baseline; 2/17 at follow-up). Over six years, the incidence rates for primary glaucoma, early and late age-related macular degeneration, and myopic maculopathy in individuals aged 35 and above were 1.6% (95%CI: 1.2%-1.9%), 4.2% (95%CI: 3.8%-4.7%), 0.2% (95%CI: 0.2%-0.3%), and 0.1% (95%CI: 0.0%-0.2%), respectively. Conclusions: The prevalence of bilateral blindness in the rural population of Yongnian County, Handan City, Hebei Province, decreased over six years due to blindness prevention and treatment efforts but remained higher than in urban areas. Meanwhile, the prevalence of bilateral visual impairment increased since the baseline survey. Cataracts continued to be the primary cause of blindness, followed by myopic retinal degeneration, glaucoma, and corneal opacity.

Lifetime cost-effectiveness of myopia control intervention for the children population.

Background: Myopia is a common eye condition and projected to affect half of the global population by 2050. Controlling its progression during childhood may prevent associated ocular diseases in later life. Certain interventions retard myopia progression but their long-term costs and consequences are not well understood. We evaluated the cost-effectiveness of myopia control via an optical approach using the Defocus Incorporated Multiple Segments (DIMS) lens over a lifetime. Methods: We constructed an individual-based, state-transition model to simulate 1) the development and progression of myopia in childhood with and without control and 2) the impact of myopia on the development of four sight-threatening complications in adulthood. We compared strategies of myopia control with 100% uptake vs. no myopia control from the societal perspective to determine whether myopia control is value for money. Results: With myopia control, the cumulative prevalence of high myopia was relatively reduced by 44.7% (5.9 vs. 10.7%) and severe visual impairment by 19.2% (2.2 vs. 2.7%) compared to no myopia control. The lifetime cost per quality-adjusted life year gained was 26 407 US dollars (USD) and is considered cost-effective compared to the threshold recommended by the World Health Organization (WHO) of one times annual per capita gross domestic product (48 359 USD). Probabilistic sensitivity analysis showed that myopia control had an 87% likelihood of being cost-effective at the WHO threshold. Conclusions: Myopia control is cost-effective when provided to all eligible children. Further investigation is required to determine if it is cost-effective for the government to subsidise myopia control in order to maximise access.

[Relationship between academic procrastination and depression in myopia junior middle school students in a district of Chongqing in 2022].

OBJECTIVE: To understand the relationship between academic delay and depression in myopic junior high school students. METHODS: Medical visual acuity examination(including far-vision examination and dioptometry) and questionnaire survey(including Middle School students' Academic Procrastination Questionnaire and Childhood Depression Scale) were conducted among 1752 junior middle school students in a district of Chongqing in June 2022. Difference analysis, correlation analysis and binary Logistic regression analysis were performed on the data obtained from myopic students. RESULTS: 1116(63.69%) students with myopia were detected, 405 students with academic delay and 1289 students with depression. Among them, 266(65.68%) and 835(64.78%) were nearsighted due to academic procrastination and depression. There were significant differences in academic procrastination and depression between myopic and non-myopic students(P<0.01). Moreover, myopic junior high school students have a greater risk of academic procrastination and depression(OR=4.94, 95%CI 3.04-8.01). CONCLUSION: Myopic junior high school students are more likely to have academic delay and depression.

Correlation analysis of myopia and dietary factors among primary and secondary school students in Shenyang, China.

Currently, the global prevalence of myopia is high and on the rise, seriously affecting the health of students. Studies have suggested that dietary factors may be associated with the occurrence and development of myopia, but the results are inconsistent. This survey aims to analyze the correlation between dietary factors and myopia while controlling for more confounding factors. A multi-stage stratified cluster sampling method was performed to select 10,619 primary and secondary school students in Shenyang for visual examination, and questionnaires were administered to 6974 of them. Logistic regression was performed with myopia as the dependent variable and the variables with p < 0.1 in the univariate analysis as independent variables. Sensitivity analysis was conducted using propensity score matching. The results showed that the overall prevalence of myopia among primary and secondary school students in Shenyang was 59.1%, with mild myopia predominating. Students who ate fresh fruits two or more times a day had a 0.69 times lower risk of myopia compared to those who did not eat fruits (95% CI 0.50-0.97). However, subgroup analysis demonstrated that this protective effect was only significant for male students, with an OR of 0.59 (95% CI 0.38-0.91). Moreover, female students who consumed sugary beverages once or more a day had a 1.8 times higher risk of myopia compared to those who did not consume sugary beverages (95% CI 1.03-3.15). Vegetable consumption, intake of fried foods, and breakfast habits were not significantly associated with myopia. In summary, excessive consumption of sugary beverages could increase the risk of myopia, especially in female students, whereas fruit intake contributed to reducing the risk of myopia, particularly in male students.

Developmental characteristics and control effects of myopia and eye diseases in children and adolescents: a school-based retrospective cohort study in Southwest China.

OBJECTIVES: To characterise the prevalence of myopia and eye diseases among school adolescents and children in Southwest China, and to evaluate the effectiveness of myopia control tools. DESIGN: Retrospective cohort study. SETTING: Across 95 basic education institutions in Southwest China. PARTICIPANTS: 96 146 children aged 3-17 years from a school-based survey conducted between 2019 and 2021. PRIMARY OUTCOME MEASURES: The data of vision assessment and eye disease examination of school students were analysed, including a total of four surveys once per semester. The prevalence of myopia categorised as low (-0.5D to -3.0D), moderate (-3.0D to -6.0D) and high (≥-6.0D), along with the prevalence of significant ocular diseases, was assessed. Stratified analyses were conducted to investigate the impact of correction time on visual acuity (VA) and biological parameters. Subsequently, the subjects across the groups were matched using the nearest neighbour method, followed by multidimensional statistical analysis. RESULTS: The prevalence of myopia among the surveyed students was 38.39%. After controlling for confounding variables, the statistical analysis revealed a 0.1 increase in mean VA within the orthokeratology group and a 0.1 decrease in VA within the spectacle group (p<0.001), with statistically significant differences in corneal radius, corneal curvature and equivalent spherical lens (p<0.05). Multivariate analysis indicated a statistically significant reduction in VA in the ophthalmopathy group compared with the control group (p=0.031). Furthermore, it was demonstrated that the risk of eye disease during vision correction was greater among older students than their younger counterparts (OR>1), and that female students exhibited a higher risk than male students (OR=1.5). CONCLUSIONS: The current high prevalence of myopia and eye diseases among Southwest China's school youths demands public health attention. Minors wearing orthokeratology lenses at night, especially in primary school, exhibit significantly improved naked-eye vision. However, vigilant eye healthcare during the correction period is crucial, especially for girls.

Handling missing data and measurement error for early-onset myopia risk prediction models.

BACKGROUND: Early identification of children at high risk of developing myopia is essential to prevent myopia progression by introducing timely interventions. However, missing data and measurement error (ME) are common challenges in risk prediction modelling that can introduce bias in myopia prediction. METHODS: We explore four imputation methods to address missing data and ME: single imputation (SI), multiple imputation under missing at random (MI-MAR), multiple imputation with calibration procedure (MI-ME), and multiple imputation under missing not at random (MI-MNAR). We compare four machine-learning models (Decision Tree, Naive Bayes, Random Forest, and Xgboost) and three statistical models (logistic regression, stepwise logistic regression, and least absolute shrinkage and selection operator logistic regression) in myopia risk prediction. We apply these models to the Shanghai Jinshan Myopia Cohort Study and also conduct a simulation study to investigate the impact of missing mechanisms, the degree of ME, and the importance of predictors on model performance. Model performance is evaluated using the receiver operating characteristic curve (AUROC) and the area under the precision-recall curve (AUPRC). RESULTS: Our findings indicate that in scenarios with missing data and ME, using MI-ME in combination with logistic regression yields the best prediction results. In scenarios without ME, employing MI-MAR to handle missing data outperforms SI regardless of the missing mechanisms. When ME has a greater impact on prediction than missing data, the relative advantage of MI-MAR diminishes, and MI-ME becomes more superior. Furthermore, our results demonstrate that statistical models exhibit better prediction performance than machine-learning models. CONCLUSION: MI-ME emerges as a reliable method for handling missing data and ME in important predictors for early-onset myopia risk prediction.

Prevalence, sociodemographic risk factors, and coverage of myopia correction among adolescent students in the central region of Portugal.

BACKGROUND: Knowing the prevalence of myopia at school age is essential to implement preventive measures and appropriate interventions, ensure access to vision care, promote a healthier educational environment and improve academic performance. The purpose of this study was to determine the prevalence of myopia and its associated sociodemographic risk factors, as well as to estimate the coverage of myopia correction among adolescents in center of Portugal. METHODS: This cross-sectional study evaluated 1115 adolescents from the 5th to the 9th year of school, with an average of 12.9 years (SD = 1.5) ranging from 10.0 to 18.0 years. Optometric evaluations were carried out in a school environment and consisted of the evaluation of distance visual acuity, assessed using a logarithmic visual acuity chart (ETDRS charts 1 and 2) at 4 m, and measured by refractive error with a pediatric autorefractometer (Plusoptix), by non-cycloplegic. Myopia was defined as spherical equivalent (SE ≤ -0.50 diopter (D)) and uncorrected visual acuity (UVA ≤ 95VAR). Adjusted logistic regression analysis was applied to investigate risk factors. RESULTS: We found a myopia rate of 21.5% and a high myopia rate of 1.4%. Higher school level and attendance at urban schools were associated with myopia, but no association was found with age or sex. Only 34.6% of myopic adolescents use the best optical correction and 26.4% do not use any type of optical correction. CONCLUSIONS: Data on the prevalence of refractive problems in Portugal are scarce and heterogeneous. This study, although regional, provides a valuable contribution with a clear and reproducible methodology, following international guidelines and filling gaps in the existing literature. The results show that the rate of myopia in this age group is similar to reports from other European studies. The high rate of adolescents with uncorrected or under-corrected myopia in Portugal is a problem that deserves attention.

Prevalence of myopic eyes in private practice and public care services in Brazil: 11 years of retrospective analysis.

PURPOSE: This study aimed to examine the prevalence of myopic eyes over 11 years (2008-2018) in a private clinic and a public assistance service. METHODS: We retrospectively evaluated 6332 individuals (12,664 eyes) between 5 and 25 years old, seen at a private clinic-CEMO (2,663 individuals) and a public service-HOIP (3,669 individuals) from 2008 to 2018. We evaluated the prevalence of myopic eyes (EE ≤-0.50) and high myopic eyes (EE ≤-6.00). RESULTS: Sex and services did not show statistical differences. The variation in the prevalence of myopic and high myopic eyes showed a random pattern during the study period (this prevalence could not be increased). Prevalences ranged from 20.7% (in 2017) to 32.4% (in 2015) for myopic eyes and from 1.6% (in 2009 and 2016) to 3.3% (in 2015) for eyes with high myopia. The prevalence of myopia showed a statistically significant increase based on the age group. CONCLUSION: The prevalence of myopic eyes did not increase in our study. The mean prevalence of myopic eyes was similar in the private clinic and public service.

The Onset and Progression of Myopia Slows in Chinese 15-Year-Old Adolescents Following Vocational Rather Than Academic School Pathways.

Purpose: The purpose of this study was to investigate the changes in spherical equivalent (SE) and axial length (AL) and cumulative incidence of myopia and high myopia in Chinese 15-year-old adolescents entering a non-academic stream of senior high school education. Methods: A total of 880 first-born twins with a baseline age range of 7 to 15 years were enrolled and followed annually until 18 years of age. Cycloplegic refractions and AL were examined. Educational exposure was divided into academic high school (AHS) and vocational high school (VHS) streams. A piecewise linear mixed-effects model was used to estimate the effect of education exposures on SE development, the slope before the age of 15 years (ß2), and the slope change at the age of 15 years (ß3) was compared between the 2 groups. Results: The curves of refractive development in a myopic direction changed in parallel in the AHS and VHS group before 15 years. For nonmyopic children, ß2 was -0.19 and -0.20 diopters (D)/year (P = 0.270), and ß3 was 0.16 and 0.14 D/year (P = 0.270), in the AHS and VHS groups, respectively. Among patients with myopia, ß2 was -0.52 and -0.54 D/year (P = 0.500), and ß3 was 0.37 and 0.32 D/year (P = 0.004), in the AHS and VHS groups, respectively. The trends in AL were similar. The 3-year cumulative incidence of myopia was 35.3% (AHS) versus 14.7% (VHS; P < 0.001), and that of high myopia was 5.7% and 3.3% (P = 0.129). Conclusions: Students undertaking a VHS rather than an AHS education have slower myopic shifts in refraction and less incident myopia after the age of 15 years.

Association between vision-related quality of life and mental health status in myopia children using various optical correction aids.

PURPOSE: To evaluate the relationship between vision-related quality of life and mental health in myopia children with various optical aids. METHODS: This cross-sectional study enrolled children aged 8-13 years, exhibiting myopia ranging from -4.50 to -0.75 D, and utilizing various optical aids for correction. Full ocular examinations and completion of two questionnaires were performed. Vision-related quality of life was evaluated using the Paediatric Refractive Error Profile (PREP), and mental health status was assessed utilising the Screen for Child Anxiety Related Emotional Disorders (SCARED). Univariate and multivariate analyses were conducted to evaluate the association between vision-related quality of life and mental health status. RESULTS: The study sample comprised 209 children with corrected myopia using single vision spectacles (100 [47.8 %]), soft contact lenses (66 [31.6 %]), and orthokeratology lenses (43 [20.6 %]). The mean age was 10.31 ± 1.65 y, and males accounted for 50.7 % of the sample. The distribution of demographic characteristics showed no significant difference among all correction types, except that the myopia duration was longer for orthokeratology lens wearers than those using spectacles (P=0.03). Contact lens showed clear benefits in almost all dimensions of vision-related quality of life, especially in appearance, satisfaction, activity and peer perceptions dimensions. The prevalence of anxiety disorders among spectacle wearers was 25.0 %, the highest among all groups. For myopia children with optical corrections, not being in the top 30 percent of their class rank, reporting lower PREP scores on symptoms, handling and peer perceptions dimensions were related with a higher prevalence of anxiety disorders. CONCLUSIONS: Lower vision-related quality of life was associated with worse mental health status of myopia children with optical corrections. Identifying this association is crucial for protecting the mental health of myopia children and enhancing corrective measures.

Machine Learning Models for Predicting Cycloplegic Refractive Error and Myopia Status Based on Non-Cycloplegic Data in Chinese Students.

Purpose: To develop and validate machine learning (ML) models for predicting cycloplegic refractive error and myopia status using noncycloplegic refractive error and biometric data. Methods: Cross-sectional study of children aged five to 18 years who underwent biometry and autorefraction before and after cycloplegia. Myopia was defined as cycloplegic spherical equivalent refraction (SER) ≤-0.5 Diopter (D). Models were evaluated for predicting SER using R2 and mean absolute error (MAE) and myopia status using area under the receiver operating characteristic (ROC) curve (AUC). Best-performing models were further evaluated using sensitivity/specificity and comparison of observed versus predicted myopia prevalence rate overall and in each age group. Independent data sets were used for training (n = 1938) and validation (n = 1476). Results: In the validation dataset, ML models predicted cycloplegic SER with high R2 (0.913-0.935) and low MAE (0.393-0.480 D). The AUC for predicting myopia was high (0.984-0.987). The best-performing model for SER (XGBoost) had high sensitivity and specificity (91.1% and 97.2%). Random forest (RF), the best-performing model for myopia, had high sensitivity and specificity (92.2% and 96.9%). Within each age group, difference between predicted and actual myopia prevalence was within 4%. Conclusions: Using noncycloplegic refractive error and ocular biometric data, ML models performed well for predicting cycloplegic SER and myopia status. When measuring cycloplegic SER is not feasible, ML may provide a useful tool for estimating cycloplegic SER and myopia prevalence rate in epidemiological studies. Translational Relevance: Using ML to predict cycloplegic refraction based on noncycloplegic data is a powerful tool for large, population-based studies of refractive error.

Smartwatch Measures of Outdoor Exposure and Myopia in Children.

Importance: Time spent outdoors has been proven effective in preventing myopia, but little is known about the association of outdoor exposure patterns with myopia. Objective: To examine the association of outdoor exposure patterns with myopic shift in children. Design, Setting, and Participants: This 1-year prospective cohort study from December 2017 to December 2018 was a secondary analysis of a cluster-randomized trial (Shanghai Time Outside to Reduce Myopia [STORM]). STORM was a school-based intervention study, recruiting 16 schools from 8 districts in Shanghai, from October 2016 to December 2018. Children without myopia at baseline who consistently wore a smartwatch for a minimum of 6 hours daily, sustained for at least 90 days, and who had complete information were included. Data analysis was performed from December 2017 to December 2018. Exposures: The outdoor exposure pattern was defined as the episode of time outdoors and instant sunlight intensity over a continuous period. Main Outcomes and Measures: Myopic shift was defined as the absolute change in refraction between the initial spherical equivalence and the follow-up spherical equivalence. Results: This study included 2976 students (mean [SD] age, 7.2 [0.6] years; 1525 girls [51.2%]). The mean (SD) daily time outdoors was 90 (28) minutes, and the mean (SD) sunlight intensity was 2345 (486) lux. Of the 12 outdoor exposure patterns, the major outdoor exposure patterns were time outdoors with at least 15 minutes, accounting for 74.9% of minutes (33 677 584 of 45 016 800 minutes). Only patterns with at least 15 minutes accompanied with no less than 2000 lux were associated with less myopic shift in refraction (for ≥15 minutes and 2000 to 3999 lux, -0.007 diopter [D] [95% CI, -0.011 to -0.002 D]; for ≥15 minutes and ≥4000 lux, -0.006 D [95% CI, -0.010 to -0.002 D]). The isotemporal substitution of patterns with at least 15 minutes and 2000 lux for other outdoor exposure patterns was positively associated with less myopic shift. Conclusions and Relevance: In this 1-year prospective cohort study of children with smartwatches, continuous outdoor exposure with at least 15 minutes accompanied with no less than 2000 lux sunlight intensity was associated with less myopic shift. These findings suggest that future outdoor interventions should focus not only on the overall time outdoors but also on the effective outdoor exposure patterns, as a means to effectively prevent myopia in children.

A clearer vision: unveiling the importance of cycloplegic refraction and the pseudomyopia prevalence in Chinese preschoolers.

BACKGROUND: This study aimed to investigate the difference between cycloplegic and noncycloplegic refraction and evaluate the pseudomyopia prevalence in Chinese preschool children during the outbreak of COVID-19. METHODS: A cross-sectional study was conducted in the Tongzhou District of Beijing, China. Refractive error was measured under both noncycloplegic and cycloplegic conditions with autorefraction. The difference between noncycloplegic and cycloplegic spherical equivalent refraction (SER) and pseudomyopia prevalence were analyzed. Pseudomyopia was defined as SER ≤-0.50D in precycloplegic assessments and >-0.50D in post-cycloplegic assessments. RESULTS: Out of the 1487 participants who were enrolled in the study, 1471 individuals (98.92%) between the ages of 3-6 years completed all required procedures. A statistically significant difference in refraction was observed between noncycloplegic and cycloplegic measurements, the median of difference in spherical equivalent refraction (SER) of 0.88D (dioptre)(0.50,1.38). There was a high intraclass correlation (ICC) between these two methods for cylinders (ICC = 0.864; 95% CI, 0.850-0.877). The median DSE for myopia, emmetropia and hyperopia were 0.25D (0.00, 0.38),0.25D (0.06, 0.50) and 1.00D (0.62, 1.38), an hypermetropes showed considerably greater differences than myopes and emmetropes (Kruskal-Wallis test, H = 231.023, P = 0.000). Additionally, girls displayed a greater DSE than boys. Furthermore, when comparing against-the-rule (ATR) and oblique astigmatism, it was found that with-the-rule (WTR) astigmatism had the largest DSE. The study found varying prevalence rates of myopia, emmetropia, and hyperopia with and without cycloplegia, which were 1.90% vs. 10.06%, 11.49% vs. 50.31%, and 86.61% vs. 39.63%, respectively. Additionally, the overall prevalence of pseudomyopia was determined to be 8.29%. Participants with pseudomyopia had a significantly higher mean difference in SER (DSE) compared to non-pseudomyopic participants. CONCLUSIONS: Cycloplegic refraction is more sensitive than a noncycloplegic one for measuring refractive error in preschool children. Pseudomyopia is prevalent in preschool children during the COVID-19 outbreak period. Our study indicates the possibility that cycloplegic refraction should be performed in preschool children routinely.

Daylight and Electric Lighting in Primary and Secondary School Classrooms in the UK-An Observational Study.

Only a few recent studies report direct assessment or monitoring of light levels in the indoor learning environment, and no consensus exists on minimum exposures for children's health. For instance, myopia is a common progressive condition, with genetic and environmental risk factors. Reduced daylight exposure, electric lighting changes, increased near-work for school children, greater academic focus, and use of display screens and white boards may have important detrimental influences. Published assessment methods had varied limitations, such as incomplete compliance from participants wearing light loggers for extended periods. Climate-Based Daylight Modelling is encouraged in UK school design, but design approaches are impractical for post-occupancy assessments of pre-existing classrooms or ad hoc modifications. In this study, we investigated the potential for direct assessment and monitoring of classroom daylight and lighting measurements. Combined with objective assessments of outdoor exposures and class time use, the classroom data could inform design and light exposure interventions to reduce the various health impacts of inadequate daylight exposure. The relevant environmental measure for myopia depends on the hypothesized mechanism, so the illuminance, spectral distribution, and temporal light modulation from the electric lighting was also assessed.

Visual Impairment, Eye Conditions, and Diagnoses of Neurodegeneration and Dementia.

Importance: Vision and eye conditions are associated with increased risk for Alzheimer disease and related dementias (ADRDs), but the nature of the association and the underlying biological pathways remain unclear. If causal, vision would be an important modifiable risk factor with viable population-level interventions. Objective: To evaluate potentially causal associations between visual acuity, eye conditions (specifically cataracts and myopia), neuroimaging outcomes, and ADRDs. Design, Setting, and Participants: A cohort and 2-sample bidirectional mendelian randomization (MR) study was conducted using UK Biobank participants and summary statistics from previously published genome-wide association studies on cataract, myopia, and AD. The participants included in the analysis were aged 55 to 70 years without dementia at baseline (calendar years 2006 to 2010), underwent genotyping, and reported on eye conditions; a subset completed visual acuity examinations (n = 69 852-71 429) or brain imaging (n = 36 591-36 855). Data were analyzed from August 15, 2022, through November 28, 2023. Exposure: Self-reported cataracts, visual acuity, and myopia measured by refraction error. Main Outcomes and Measures: ADRD, AD, and vascular dementia were identified from electronic medical records. Total and regional brain volumes were determined using magnetic resonance imaging. Results: The sample included 304 953 participants (mean [SD] age, 62.1 (4.1) years; 163 825 women [53.72%]); 14 295 (4.69%) had cataracts and 2754 (3.86%) had worse than 20/40 vision. Cataracts (hazard ratio [HR], 1.18; 95% CI, 1.07-1.29) and myopia (HR, 1.35; 95% CI, 1.06-1.70) were associated with a higher hazard of ADRD. In MR analyses to estimate potential causal effects, cataracts were associated with increased risk of vascular dementia (inverse variance-weighted odds ratio [OR], 1.92; 95% CI, 1.26-2.92) but were not associated with increased dementia (OR, 1.21; 95% CI, 0.98-1.50). There were no associations between myopia and dementia. In MR for potential reverse causality, AD was not associated with cataracts (inverse variance-weighted OR, 0.99; 95% CI, 0.96-1.01). Genetic risk for cataracts was associated with smaller total brain (ß = -597.43 mm3; 95% CI, -1077.87 to -117.00 mm3) and gray matter (ß = -375.17 mm3; 95% CI, -680.10 to -70.24 mm3) volumes, but not other brain regions. Conclusions and Relevance: In this cohort and MR study of UK Biobank participants, cataracts were associated with increased risk of dementia, especially vascular dementia, and reduced total brain volumes. These findings lend further support to the hypothesis that cataract extraction may reduce the risk for dementia.

[Analysis of myopia status and related factors among primary school students in a certain district of Beijing City in 2022].

Objective: To analyze the current situation of myopia and its related factors among primary school students in a certain district of Beijing City in 2022, and provide a basis for the risk assessment of myopia among primary school students. Method: In June 2022, a cluster sampling method was used to include 376 third-grade students from a primary school in a certain district of Beijing. A questionnaire survey was conducted to collect basic information about students, including eye usage habits, reading and writing postures, and parents' myopia conditions. The examination of students' distant visual acuity and refractive status was performed. A multivariate logistic regression model was used to analyze the related factors of myopia occurrence. Results: The age of 376 primary school students was (8.87±0.417) years old, with 48.40% (182) being male. A total of 196 myopia cases were identified, with a myopia rate of 52.13%. The results of the multivariate logistic regression model analysis showed that students who sometimes read while lying down (OR=2.003, 95%CI: 1.128-3.555), often read while lying down (OR=18.853, 95%CI: 4.512-78.778), had outdoor activity time less than 120 minutes per day (OR=4.937, 95%CI: 2.4464-9.892), were engaged in indoor break activities (OR=4.995, 95%CI: 2.773-8.996), performed eye exercises less than once per day (OR=8.710, 95%CI: 4.464-16.995), had a reading distance from the book less than 30 cm (OR=5.098, 95%CI: 2.410-10.787), occasionally maintained a fist distance from the edge of the desk (OR=1.918, 95%CI: 1.086-3.385), and had high school desks and tables (OR=5.325, 95%CI: 1.465-19.359) could have a higher risk of myopia occurrence, compared with those who never read while lying down, had outdoor activity time more than 120 minutes per day, maintained outdoor break activities, performed eye exercises more than once per day, had a reading distance from the book more than 30 cm, always maintained a fist distance from the edge of the desk, and had short school desks and tables. Conclusion: The incidence rate of myopia among primary school students in a certain district of Beijing City. in 2022 is relatively high. The occurrence of myopia is related to insufficient outdoor activity time and poor eye usage habits.

Survey on pattern of myopia in school children in Hangzhou after the COVID-19 pandemic: a school-based vision screening study.

BACKGROUND: Myopia is a major health issue around the world. Myopia in children has increased significantly during the COVID-19 pandemic in China, but reports are scarce on the prevalence of myopia following the pandemic. This study collected vision screening data of school children in China for five consecutive years to observe the changes in myopia after the pandemic and compare the observed prevalence of myopia before and after the pandemic. METHODS: A school-based vision screening study used stratified samplings to collect the vision screening data in school children aged 6-13 from 45 primary schools in Hangzhou. Vision screening data including uncorrected visual acuity(UCVA) and spherical equivalent refraction(SER). Calculating the mean of SER and the prevalence of myopia and hyperopia from 2019 to 2023. RESULTS: A total of 79,068 screening results (158,136 eyes) were included in the analysis. A substantial myopic shift (approximately -0.30 diopters [D] on average) was found in 2020 and 2021 compared with 2019 in all age groups and a substantial myopic shift (approximately 0.4 D on average) was found in 2022 compared with 2021. A slight myopic shift (approximately -0.14 D on average) was found in 2023 compared with 2022. The prevalence of myopia in all age groups was the highest for five years in 2020 or 2021, which was 31.3% for 6-year-olds, 43.0% for 7-year-olds, and 53.7% for 8-year-olds. A positive change in the prevalence rate of myopia was found at 6 years old (0.59%, 0.12%, 0.36%, 0.25%, p < 0.001). The change in prevalence rate in myopia was shifted slightly in children aged 10-13 years. Children aged 8 to 13 years had a slight increase in myopia prevalence from 2022 to 2023. The prevalence of hyperopia was low and stable in all grade groups, ranging from 0.7% to 2.2% over five years. CONCLUSION: Myopia in children has increased rapidly during the COVID-19 pandemic. After the pandemic, the prevalence of myopia in children gradually decreased temporarily and then rebounded. Myopic shift was more apparent in younger children. Myopic shift in children may be related to the reduction of outdoor time, less light, and near work habits, and further research is needed.

Prevalence and associated factors of myopia among adolescents aged 12-15 in Shandong Province, China: a cross-sectional study.

Myopia is a growing concern worldwide, especially among adolescents. This study aimed to investigate the prevalence and associated factors of myopia in adolescents aged 12-15 in Shandong Province, China. This cross-sectional study adhered to the Strengthening the Reporting of Observational Studies in Epidemiology guidelines and involved stratified random cluster sampling of 128,678 students from 186 middle schools across 17 cities in Shandong Province. Data collection was conducted from March to April 2024. We excluded students with organic eye diseases, abnormal binocular vision functions, or a history of eye injuries or surgeries. Myopia was assessed using the standard logarithmic visual acuity chart and autorefractor without inducing ciliary muscle paralysis. A comprehensive questionnaire survey was conducted to gather demographic characteristics and daily life behaviors. With the chi-squared test for univariable analysis and multivariable logistic regression for identifying significant factors. This study included 126,375 participants, with a gender distribution of 51.02% male and 48.98% female. The overall prevalence of myopia was 71.34%. Higher prevalence was observed in girls (72.26%) compared to boys (70.45%), and the prevalence increased with age, peaking at 73.12% in 15-year-olds. Urban residents had a higher prevalence (71.86%) than rural (70.39%). Factors such as increased frequency of eye usage while lying down or leaning forward, frequent use of eyes while walking or riding in a car, prolonged screen time, and extended homework duration were associated with higher odds of developing myopia. Conversely, higher frequency of outdoor exercise, maintaining proper posture during reading and writing, greater distance from eyes to screen, and longer sleep duration were associated with lower odds. Additionally, female gender, older age, urban residence, and parental history of myopia increased the risk. The high prevalence of myopia among adolescents in Shandong Province was influenced by a combination of demographic, behavioral, and environmental factors. The study highlighted the importance of lifestyle modifications, such as increasing outdoor activities and maintaining proper visual habits, limiting the duration of screen exposure and homework sessions, and extending sleep duration, to mitigate the risk of developing myopia. These findings underscored the need for targeted public health interventions and educational campaigns to address this significant public health issue.