Objective and Subjective Behavioral Measures in Myopic and Non-Myopic Children During the COVID-19 Pandemic

Prevalence of Myopia Among Schoolchildren and the Impact of Increased Screen Time: A Systematic Review

Myopia is the most frequent kind of refractive error and affects hundreds of millions of people. Growing evidence suggests that extended exposure to digital screens may exacerbate nearsightedness in children and young people. The purpose of this review is to compile data on the link between too much time in front of a screen and nearsightedness in young people so far. The principles of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guided the methods used and the format of the resulting report. Articles published between January 1, 2000, and June 30, 2023, were found by searching Medline, PubMed, ScienceDirect, Google Scholar, CINAHL, the Cochrane Library, and Scopus. Studies reporting an association between myopia and time spent in front of screens in children and young adults were considered eligible. The initial search yielded a total of 1,251 studies. After eliminating duplicates and reviewing the titles and abstracts, 64 full-text articles were evaluated for eligibility. Ultimately, 15 of these studies were included in the final analysis. The 15 studies involved a total of 59,775 participants and were conducted in various countries, including China, Singapore, and the United States. Overall, the evidence did not support a significant association between screen time and myopia in school children and young adults. There is conflicting evidence on the link between screen time and myopia in children and adolescents. More research is needed to determine whether or not digital screen use is a risk factor for myopia. The complex association between screen time and myopia is not fully understood at this time because of the variability of the included studies. These results have significant public health implications since they may be used to guide recommendations for screen time use in children and the young population.

Smart Devices in Optometry: Current and Future Perspectives to Clinical Optometry

There is a huge unmet need for eye care with more than a hundred million people living without basic eye care services and facilities. There is an exigency to deploy adequate resources in terms of manpower and equipment to address this. The usage of smart devices in optometry and eye care practice has been gaining momentum for last half a decade, due to the COVID-19 pandemic and technological advancements in telemedicine. These smart devices will help facilitate remote monitoring of important visual functions, ocular signs and symptoms, thus providing better eye care services and facilities and promoting outreach services. Smart devices in optometry exist in the form of gadgets that can be worn in the wrist, and spectacle-mounted or head-mounted devices. On the other hand, with the ubiquitous nature of smartphones, a large number of smartphone applications have been developed and tested for advanced optometry and primary eye care practice, which may potentially reduce the burden of inadequate resources and the unmet need for eye care. This article aims to give an overview of the current trends and future perspectives on the application of such smart devices in optometric practice.

Genetic correlation and causal relationship between sleep and myopia: a mendelian randomization study

Purpose

To investigate the genetic correlation and causal links between sleep traits (including sleep duration, chronotype, and insomnia) and myopia.

Methods

Summary data on three sleep traits (sleep duration, chronotype and insomnia) and myopia from FinnGen (n = 214,211) and UK Biobank (n = 460,536) were analyzed using linkage disequilibrium score regression (LD Score), univariable and multivariable mendelian randomization (MR) experiments and Causal Analysis Using Summary Effect (CAUSE) estimation.

Results

LD Score regression detected candidate genetic correlation between sleep traits and myopia, such as sleep duration, chronotype (Genetic Correlation Z-score >10.00, h2_observed_p < 0.005, Lambda GC > 1.05, p > 0.05). Univariable MR analyses indicated that increased sleep duration has a promotional effect on the occurrence of myopia (p = 0.046 < 0.05, P_FDR = 0.138 < 0.2, OR = 2.872, 95% CI: 1.018-8.101). However, after accounting for potential confounding factors, multivariable MR and CAUSE analysis did not provide evidence for a causal effect of the three sleep traits on myopia.

Conclusion

There may be a potential genetic correlation between sleep duration, chronotype and myopia. However, neither of sleep duration, chronotype or insomnia had causal effect on myopia.

Development of the University of Houston near work, environment, activity, and refraction (UH NEAR) survey for myopia

CLINICAL RELEVANCE

There is a need to better elucidate demographic and behavioural factors that are contributing to the rising prevalence of myopia. Doing so will aid in developing evidence-based recommendations for behavioural modifications to prevent onset and slow progression of myopia in children.

BACKGROUND

The contributions of environmental and behavioural factors in myopia remain unclear. The goal of this work was to provide a standardised survey to better understand risk factors for myopia.

METHODS

Development of the survey was carried out in 4 phases. In phase 1, three methods (direct, lay terms, and indirect) of parental reporting for the presence of myopia in their child were investigated through a questionnaire (N = 109) to determine sensitivity and specificity. The best method determined from phase 1 was used in phase 2, where questions regarding demographics, ocular history, and visual behaviour were compiled and refined. In phase 3, the survey was administered to focus groups of parents (N = 9). In phase 4, a scoring system was developed.

RESULTS

The highest sensitivity for parental reporting for myopia of their child was the indirect method (0.84), and the lowest sensitivity was the direct method (0.41). The highest specificity was the direct method (0.86), once excluding the 'do not know' responses, and the lowest specificity was the indirect method (0.53). The direct method yielded a 53.2% 'do not know' response rate, 50.5% for the lay method, and 1.8% for the indirect method. Time to complete the survey was 10:09 ± 2:45 minutes.

CONCLUSION

This study provides a comprehensive and up-to-date myopia risk factor survey that can be utilised by researchers and clinicians. Parents found the survey to be easy to understand and relatively quick to answer, and the scoring system allows quantification of behaviours across different categories using provided equations.

Associations of meeting 24-hour movement behavior guidelines with prescribed eyeglasses/contact lenses among children and adolescents

BACKGROUND

Vision health is crucial for many aspects of life especially in developing populations such as children and adolescents. However, there is a high proportion of children and adolescents who suffer from visual impairments. Notably, accumulating evidence indicates that meeting the 24-hour movement behaviors (24-HMB) guidelines is associated with positive physical and mental health outcomes in children and adolescents. However, the relationship between being prescribed eyeglasses/contact lenses and meeting the 24-HMB guidelines has yet to be investigated. Thus, this study aimed to address this gap in the existing literature by using the 2021 National Survey of Children's Health (NSCH) dataset.

METHODS

In this cross-sectional study, data was retrieved from the 2021 NSCH. A total of 14,193 U.S. children and adolescents aged between 6 and 17 years were included for data analyses. We used items of the NSCH concerning the 24-HMB guidelines (i.e., physical activity, screen time, and sleep duration) and prescription of eyeglasses/contact lenses that were answered by the legal guardian of the children. Binary logistic regression was performed to investigate whether meeting the 24-HMB guidelines is associated with prescription eyeglasses/contact lenses and whether wearing eyeglasses/contact lenses predicts adherence to the 24-HMB guidelines among children and adolescents.

RESULTS

More than half of the participants (59.53%) wore eyeglasses/contact lenses and only 8.40% of them met all three of the 24-HMB guidelines. Compared to meeting none of the 24-HMB guidelines, meeting one (OR = 0.76, 95% CI = 0.62-0.93, p = 0.008), two (OR = 0.54, 95% CI = 0.43-0.67, p < 0.001), and all three 24-HMB guidelines (OR = 0.47, 95% CI = 0.34-0.64, p < 0.001) were associated with a lower risk of being prescribed eyeglasses/contact lenses among children and adolescents.

CONCLUSIONS

The findings of the current study provided evidence that the prevalence of U.S. children and adolescents aged between 6 and 17 years who wore eyeglasses/contact lenses was relatively high. Furthermore, meeting the 24-HMB guidelines was associated with a lower risk of being prescribed eyeglasses/contact lenses. Future studies focusing on the effects of 24-HMB interventions on vision health among children and adolescents are needed to better inform public health actions.

Associations Between Changes in 24-Hour Movement Behaviors in Children and Adolescents During the COVID-19 Pandemic: A Systematic Review and Mediation-Based Meta-Analysis

BACKGROUND

Although 24-hour movement behaviors are known to be interconnected, limited knowledge exists about whether change in one behavior during the COVID-19 pandemic (eg, increased screen time) was associated with change in another (eg, reduced physical activity or sleep). This review estimates mediational associations between changes in children's physical activity, screen time, and sleep during the COVID-19 pandemic.

METHODS

We included studies published between January 1, 2020 and June 27, 2022, in the PubMed/MEDLINE, Embase, PsycINFO, SPORTDiscus, and Web of Science databases. Summary data were extracted from included studies and analyzed with random-effects meta-regression.

RESULTS

This review included 26 studies representing 18,959 children across 18 mid-high-income countries (53% male; mean age, 11.5 [2.9] y). There was very good evidence of decreased total daily physical activity (factor change, 0.62; 90% CI, 0.47-0.81) and strong evidence of increased screen time (1.56; 90% CI, 1.38-1.77). There was very good evidence of decreased moderate to vigorous physical activity (0.75; 90% CI, 0.62-0.90) and weak evidence of increased sleep (1.02; 90% CI, 1.00-1.04). Mediational analysis revealed strong evidence that most of the reduction in total daily physical activity from before, to during, the pandemic was associated with increased screen time (0.53; 90% CI, 0.42-0.67). We observed no further mediational associations.

CONCLUSION

Increased reliance on and use of screen-based devices during the COVID-19 pandemic can be linked with reduced child and adolescent physical activity. This finding links COVID-related restrictions to potential displacement effects within child and adolescent 24-hour movement behavior.

Compensatory Interactions between Corneal and Internal Astigmatism despite Lifestyle Changes

This study explores whether children's refractive errors and visual behaviors reverted to pre-COVID-19 levels a year after normal schooling resumed in Hong Kong as well as the impact of corneal and internal astigmatism on refractive astigmatism development. Vision survey data and questionnaire results collected in 2022 (n = 119) and 2020 (n = 173) were compared. Cross-sectional data showed similar proportions of astigmatism (cylindrical power ≥ 0.75 D) in the 2020 (49.1%) and 2022 cohorts (55.5%). Despite a 0.28 D increase in corneal astigmatism, a compensatory 0.24 D increase in internal astigmatism of opposite direction kept refractive astigmatism relatively stable. The questionnaire data showed that children spent an additional 0.5 h/day outdoors on weekends post-resumption of normal schooling but engaged in more near-work activities, especially non-screen near-work, by approximately 1 h/day on both weekdays and weekends. These findings were supported by longitudinal data from 72 children who participated in both surveys. This study highlights the significant role of corneal and internal astigmatism in refractive astigmatism changes. Despite the return to in-person classes, children's total near-work time increased and astigmatism remained high. These findings underscore the need for comprehensive strategies to reduce the high environmental risks for refractive error development in children.

Delayed melatonin circadian timing, lower melatonin output, and sleep disruptions in myopic, or short-sighted, children

STUDY OBJECTIVES

This study investigated the differences in melatonin circadian timing and output, sleep characteristics, and cognitive function in myopic and non-myopic (or emmetropic) children, aged 8-15 years.

METHODS

Twenty-six myopes (refractive error [mean ± standard error mean] -2.06 ± 0.23 diopters) and 19 emmetropes (-0.06 ± 0.04 diopters), aged 11.74 ± 2.31 years were recruited. Circadian timing was assessed using salivary dim-light melatonin onset (DLMO), collected half-hourly for 7 hours, beginning 5 hours before and finishing 2 hours after individual average sleep onset in a sleep laboratory. Nocturnal melatonin output was assessed via aMT6s levels from urine voids collected from 05:30 pm to 8:00 am the following morning. Actigraphy-derived objective sleep timing were acquired for a week prior to the sleep laboratory visit. Cognitive assessments of sustained attention (using psychomotor vigilance task [PVT]) and working memory (using digit spans) were performed on the night of sleep laboratory.

RESULTS

Myopic children (9:07 pm ± 14 minutes) exhibited a DLMO phase-delay of 1 hour 8 minutes compared to emmetropes (7:59 pm ± 13 minutes), p = 0.002. aMT6s melatonin levels were significantly lower among myopes (18.70 ± 2.38) than emmetropes (32.35 ± 6.93, p = 0.001). Myopes also exhibited significantly delayed sleep onset, delayed wake-up time, poor and reduced sleep, and more evening-type diurnal preference than emmetropes (all p < 0.05). Finally, myopes showed a slower reaction time in the PVT (p < 0.05), but not digit span tasks at night.

CONCLUSIONS

These findings suggest a potential association between circadian rhythm dysfunction and myopia in children.

Utility of the Actiwatch Spectrum Plus for detecting the outdoor environment and physical activity in children

PURPOSE

To describe the performance of the Actiwatch Spectrum Plus (Philips, Respironics) for determining real world indoor and outdoor environments and physical activity in children.

METHODS

Children wore the device while performing 10 different activities, ranging from sedentary to vigorous physical-activity, and under different indoor and outdoor conditions. Repeated measures ANOVA was implemented via mixed effects modeling to determine illuminance (lux) and physical activity (counts per 15 s, CP15) across conditions. Receiver operator characteristics (ROC) analysis assessed the accuracy to detect indoor versus outdoor settings.

RESULTS

Illuminance was found to be statistically different across indoor (793 ± 348 lux) and outdoor (4,413 ± 518 lux) conditions (P<.0001), with excellent diagnostic accuracy to detect indoor versus outdoor settings (Area under the ROC Curve, AUC 0.94); 1088 lux was identified as the optimal threshold for outdoor illuminance (sensitivity: 93.0%; specificity: 85.0%). Using published activity ranges, we found that when children were sitting, 94% of the physical-activity readings were classified as sedentary or light. When children were walking, 88% of readings were classified as light, and when children were running, 77% of readings were classified as moderate or vigorous.

CONCLUSION

The Actiwatch Spectrum Plus performed well during real world activities in children, showing excellent diagnostic accuracy at 1088 lux as a threshold to detect indoor versus outdoor environments and in categorizing physical activity.

Subjective behavioral measures in myopic and pre-myopic children before and after the COVID lockdown

Background

There are environmental factors that may contribute to the onset of myopia. This study aims to evaluate the children's lifestyle changes before and after the COVID-19 lockdown and how they can influence their vision.

Methods

The same questionnaire was administered to children aged between 5 and 7 in Spain every year in September before (2017-2019) and after the COVID-19 lockdown (2020-2021). All the children also passed a vision exam consisting of the measurement of visual acuity (VA) and determination of objective and subjective refraction. Children were classified as myopes, pre-myopes, or hyperopes. The cut-off points to define the refractive error were established according to the value of the spherical equivalent (SE): hyperopia (SE > +0,75D), myopia (SE ≤ -0,5D), or pre-myopia (-0.5D < SE ≥ +0.75D). Data analysis is performed with the SPSS 27.0 software (SPSS Inc., Chicago, Illinois).

Results

In the pre-COVID period, the pre-myopes were the ones who spent the longest time outdoors, and after the COVID lockdown, there were no differences between groups. There neither were any differences in the time spent doing near-work activities between the groups in both periods (p > 0.05). Regarding the spherical equivalent, in the pre-COVID period, the mean value was 0.75 ± 2.09D and after the COVID lockdown, it was 0.47 ± 1.88D (p < 0.001).

Conclusion

Pre-myopes spent more time outdoors than myopes in the pre-COVID period, while myopes spent more time using digital devices. All these differences do not exist after the COVID lockdown, with a general increase in the time spent outdoors and a decrease in the use of digital devices. Further studies are needed to know if these lifestyle changes remain and how they influence the onset of myopia.

Prevalence Trend of Myopia during the Post-COVID-19 Epidemic Period among Preschoolers: A Prospective School-based Study

SIGNIFICANCE

Changes in behavior and lifestyle during the post-coronavirus disease 2019 (COVID-19) epidemic may have some impact on myopia rates in preschoolers, and exploring the changes in myopia rates in preschool children may inform the formulation of myopia prevention and control policies.

PURPOSE

This study aimed to investigate the prevalence of myopia in preschool children during the post-COVID-19 epidemic period in Xuzhou, China.

METHODS

A series of cross-sectional school-based studies was conducted. A total of 117,632 preschool children aged 3 to 6 years were subjected to annual vision screening from 2019 to 2021. Spot photo screening was used to record the spherical equivalent refraction for each child and to analyze the prevalence of myopia by age, sex, and region during the post-COVID-19 epidemic period.

RESULTS

A total of 113,979 preschool children were included in the analysis, of whom 60,784 (53.3%) were male and 53,195 (46.7%) were female. For all children, the mean ± standard deviation spherical equivalent refraction in 2019, 2020, and 2021 was +0.32 ± 0.50, +0.34 ± 0.55, and +0.34 ± 0.54 D, respectively (all P < .05), indicative of a very slight hyperopic shift. In all age groups, the change in mean spherical equivalent refraction and its distribution were relatively stable. From 2019 to 2021, the overall prevalence of myopia in preschool children was 3.1, 3.3, and 3.5%, respectively. The rise in myopia rates was minimal. The largest increase in the annual prevalence of myopia was seen among children aged 6 years, at 0.5%, followed by those aged 5 years (0.4%) and aged 3 years (0.4%). The prevalence was higher in boys than girls and in urban versus rural areas.

CONCLUSIONS

During the post-COVID-19 epidemic period, the refractive status of Xuzhou preschool children remained stable.

Using Light Meters to Investigate the Light-Myopia Association - A Literature Review of Devices and Research Methods

With the increasing prevalence of myopia, evaluating its relationship with objective light exposure as a potential adjustable environmental factor in myopia development has been an emerging research field in recent years. From a thorough literature search, we identify ten wearable light meters from human studies on light exposure and myopia and present an overview of their parameters, thereby demonstrating the wide between-device variability and discussing its implications. We further identify 20 publications, including two reanalyses, reporting investigations of light-myopia associations with data from human subjects wearing light meters. We thoroughly review the publications with respect to general characteristics, aspects of data collection, participant population, as well as data analysis and interpretation, and also assess potential patterns regarding the absence or presence of light-myopia associations in their results. In doing so, we highlight areas in which more research is needed as well as several aspects that warrant consideration in the study of light exposure and myopia.

Refractive Error Changes Due to COVID-19 Pandemic Confinement in Children from Puerto Rico: A Retrospective Study

SIGNIFICANCE

The progression of myopia increased in children after the pandemic confinement. A myopic shift in the refractive error of the Hispanic population was found regardless of the refractive status of the school-aged children studied.

PURPOSE

This study aimed to evaluate the refractive error in Puerto Rican children before and after the COVID-19 pandemic. We were interested in whether there was a significant change in refractive error attributed to online learning during the pandemic lockdown.

METHODS

A retrospective record review of children aged 7 to 18 years who underwent a comprehensive visual evaluation between 2018 and 2021 at the Inter American Eye Institute in Puerto Rico was performed. The spherical equivalent pre- and post-lockdown was compared. The study excluded the best-corrected visual acuities worse than 20/40, any corneal or retinal disease, and amblyopia.

RESULTS

In total, 801 records were included in this study. The mean age was 12.7 ± 3.2 years, with 50.3% male and 49.7% female children. The mean spherical equivalent for the right and left eyes was similar ( r = 0.93, P ≤ .001). A significant difference in the mean spherical equivalent was found pre- and post- lockdown (0.22 ± 0.59 D, t800 = 10.44, P ≤ .001). A myopic shift post-lockdown was significant for all ages except those in the 7- (0.13 ± 0.79 D, t28 = 0.84, P = .40) and 8-year-old range (0.12 ± 0.65 D, t40 = 1.22, P = .23), respectively. No significant change was found between sexes before (0.16 ± 0.12 D; t799 = 1.38, P = .16) and after (0.15 ± 0.13 D; t799 = 1.19, P = .23) confinement.

CONCLUSIONS

The current study revealed a significant myopic shift in Hispanic school-aged children as a result of the pandemic confinement.

Longitudinal Changes in Choroidal Structure Following Repeated Low-Level Red-Light Therapy for Myopia Control: Secondary Analysis of a Randomized Controlled Trial

PURPOSE

Repeated low-level red-light (RLRL) therapy has been confirmed as a novel intervention for myopia control in children. This study aims to investigate longitudinal changes in choroidal structure in myopic children following 12-month RLRL treatment.

MATERIALS AND METHODS

The current study is a secondary analysis from a multicenter, randomized controlled trial (NCT04073238). Choroidal parameters were derived from baseline and follow-up swept-source optical coherence tomography scans taken at 1, 3, 6, and 12 months. These parameters included the luminal area (LA), stromal area (SA), total choroidal area (TCA; a combination of LA and SA), and choroidal vascularity index (CVI; ratio of LA to TCA), which were automatically measured by a validated custom choroidal structure assessment tool.

RESULTS

A total of 143 children (88.3% of all participants) with sufficient image quality were included in the analysis (n=67 in the RLRL and n=76 in the control groups). At the 12-month visit, all choroidal parameters increased in the RLRL group, with changes from baseline of 11.70×10 3  μm 2 (95% CI: 4.14-19.26×10 3  μm 2 ), 3.92×10 3  μm 2 (95% CI: 0.56-7.27×10 3  μm 2 ), 15.61×10 3  μm 2 (95% CI: 5.02-26.20×10 3  μm 2 ), and 0.21% (95% CI: -0.09% to 0.51%) for LA, SA, TCA, and CVI, respectively, whereas these parameters reduced in the control group.

CONCLUSIONS

Following RLRL therapy, the choroidal thickening was found to be accompanied by increases in both the vessel LA and SA, with the increase in LA being greater than that of SA. In the control group, with myopia progression, both the LA and SA decreased over time.

Effects of behaviors and surrounding environment on myopia before and during the COVID-19 pandemic: a longitudinal analysis of children and adolescents in China

Aim

To investigate the relationship between related factors and visual acuity of Chinese school students before and during the COVID-19 pandemic.

Subject and methods

Chinese students from primary and secondary schools were included from the Chinese National Surveys on Students' Constitution and Health CNSSCH (2019). A total of 1496 participants completed follow-ups in June and December 2020, respectively. Generalized estimating equations were used to test the differences in visual environment. Logistic regression models were utilized to examine the roles of behaviors and surrounding environment changes associated with myopia before and during the pandemic.

Results

The prevalence of myopia was 47.7%, 55.6%, and 57.2% in baseline and two follow-ups, respectively. Significant differences existed for gender, learning level, and region (all P < 0.05). The proportion of new myopia and myopia torsion was the highest in the primary schools. Multivariate logistic regression analysis found that screen time ≥ 4h/d (OR = 2.717), poor eye habits (OR = 1.477), insufficient lighting for studying at night (OR = 1.779), desk or roof lamps only (OR = 1.388), and poor sleep quality (OR = 4.512) were the risk factors for myopia (all P < 0.05), and eye exercises (OR = 0.417), milk intake (OR = 0.758), and eggs intake (OR = 0.735) were the protective factors for myopia (all P < 0.05).

Conclusion

Prevalence of myopia increased among Chinese students before and during the COVID-19. It is necessary to pay more attention to the pupils' visual acuity, especially in primary school students, in the future.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10389-023-01900-w.

Myopia risk behaviour related to the COVID-19 lockdown in Europe: The generation R study

PURPOSE

To battle the spreading of the COVID-19 virus, nationwide lockdowns were implemented during 2020 and 2021. Reports from China revealed that their strict home confinements led to an increase in myopia incidence. The Netherlands implemented a more lenient lockdown, which allowed children to go outside. We evaluated the association between COVID-19 restrictions, myopia risk behaviour and myopia progression in Dutch teenagers.

METHOD

A total of 1101 participants (mean age 16.3 ± 3.65 yrs) completed questionnaires about their activities before, during and after lockdown (March-October 2020). We used a repeated-measures ANOVA to compare time use between these time periods. Ocular measurements were acquired before the COVID-19 pandemic when participants were 13 years old; only 242 participants had ocular measurements at 18 years of age at the time of this analysis. Linear regression analyses were used to evaluate the association between lifestyle factors and myopia progression.

RESULTS

Children were on average 16.2 (1.03) years of age during lockdown. Total nearwork increased from 8.11 h/day to 11.79 h/day, and remained higher after lockdown at 9.46 h/day (p < 0.001). Non-educational nearwork increased by 2.22 h/day (+49%) during lockdown and was associated with faster axial length progression (B 0.002 mm/h/year; SE 0.001 p = 0.03). Before and during lockdown, the mean time spent outdoors was similar (1.78 h/day and 1.80 h/day, respectively). After lockdown, time spent outdoors decreased to 1.56 h/day (p < 0.001).

CONCLUSION

The Dutch lockdown significantly increased digitised nearwork in adolescents but did not affect outdoor exposure. The changes in time spent performing nearwork remained after the lockdown measures had ended. We expect that the COVID-19 pandemic may lead to an increase in myopia prevalence and progression in European children.

Myopia Progression during the COVID-19 Era: A Systematic Review and Meta-analysis

BACKGROUND

To evaluate myopia progression during the novel coronavirus disease 2019 (COVID-19) pandemic and its risk factors.

METHODS

We searched PubMed, Scopus, and Web of Science to find literature until August 2022 related to COVID-19 pandemic and myopia progression. Outcomes of myopia progression included axial length (AL) and spherical equivalent (SE). Factors of screen time and outdoor activity time were analyzed.

RESULTS

Thirty-three studies were included in this meta-analysis. Compared to the same period before the COVID-19 pandemic, myopia prevalence increased (OR = 1.11; 95% CI, 1.05-1.18). The outcomes of SE decreased -0.61 diopter (95% CI, -0.98 to -0.23), and AL increased 0.42 mm (95% CI, 0.13-0.7). Mean screen time was increased 6.25 hours/day (95% CI, 4.84-7.66), and outdoor activity time was decreased -1.52 hours/day (95% CI, -3.20 to -0.15).

CONCLUSION

Establishing care policies is necessary to restrict behavioral changes and their consequences during the pandemic.

Topical Review: Studies on Management of Myopia Progression from 2019 to 2021

SIGNIFICANCE

Myopia is a common eye condition that increases the risk of sight-threatening complications. Each additional diopter increases the chance of complications. The purpose of this review was to make an overview of myopia control treatment options for children with myopia progression.In this nonsystematic review, we searched PubMed and Cochrane databases for English-language studies published from 2019 to September 2021. Emphasis was given to selection of randomized controlled trials. Nineteen randomized controlled trials and two retrospective studies were included. Topical atropine and orthokeratology remain the most used treatments, whereas lenses with novel designs are emerging treatments. Overall myopia progression in the treatment groups for low-dose atropine and orthokeratology was lower than in the control groups, and their efficacy was reported in several randomized controlled trials and confirmed by various systematic reviews and meta-analysis. The findings of myopia progression and axial elongation for the MiSight, defocus incorporated multiple segment spectacle lens, highly aspherical lenslets, and diffusion optics technology spectacle lens were comparable. Public health interventions to optimize environmental influences may also be important strategies to control myopia. Optimal choice of management of myopia depends on treatment availability, acceptability to child and parents, and specific patient features such as age, baseline myopia, and lifestyle. Eye care providers need to understand the advantages and disadvantages of each therapy to best counsel parents of children with myopia.

Myopia and axial length in school-aged children before, during, and after the COVID-19 lockdown-A population-based study

Background

Myopic shift had been observed during the COVID-19 lockdown in young school children. It remains unknown whether myopic shift is accompanied with increase in axial length. We aimed to evaluate the impact of the COVID-19 lockdown on myopia and axial length of school children in China by comparing them before, during and after the lockdown.

Methods

In this population-based cross-sectional study, school-based myopia screenings were conducted in the Fall of 2019, 2020, and 2021 (representing before, during and after COVID-19 lockdown respectively) in Chengdu, China. Myopia screenings were performed on 83,132 students aged 6 to 12 years. Non-cycloplegic refractive error was examined using NIDEK auto-refractor (ARK-510A; NIDEK Corp., Tokyo, Japan) and axial length was measured using AL-Scan (NIDEK Corp., Tokyo, Japan). Spherical equivalent (SER, calculated as sphere+ 0.5^*cylinder), prevalence of myopia (SER ≤ -0.50 D), and axial length were compared across 3 years stratified by age.

Results

Myopia prevalence rate was 45.0% (95% CI: 44.6-45.5%) in 2019, 48.7% (95% CI: 48.3-49.1%) in 2020, and 47.5% (95% CI: 47.1-47.9%) in 2021 (p < 0.001). The mean non-cycloplegic SER (SD) was -0.70 (1.39) D, -0.78 (1.44) D, and -0.78 (1.47) D respectively (p < 0.001). The mean (SD) axial length was 23.41 (1.01) mm, 23.45 (1.03) mm, and 23.46 (1.03) mm across 3 years respectively (p < 0.001). From the multivariable models, the risk ratio (RR) of myopia was 1.07 (95% CI: 1.06-1.08) times, the SER was 0.05 D (95% CI: 0.04 D to 0.06 D) more myopic and the mean axial length increased by 0.01 mm (95% CI: 0.01 mm to 0.02 mm) in 2020 compared to 2019. In 2021, the risk ratio (RR) of myopia was 1.05 (95% CI: 1.04-1.06), the mean SER was 0.06 D (95% CI: 0.05 D to 0.07 D) more myopic, and the mean axial length increased by 0.03 mm (95% CI: 0.02 mm to 0.04 mm) compared to 2019.

Conclusions

The COVID-19 lockdown had significant impact on myopia development and axial length, and these impacts remained 1 year after the lockdown. Further longitudinal studies following-up with these students are needed to help understand the long-term effects of COVID-19 lockdown on myopia.

Assessment of Changes in Child and Adolescent Screen Time During the COVID-19 Pandemic: A Systematic Review and Meta-analysis

IMPORTANCE

To limit the spread of COVID-19, numerous restrictions were imposed on youths, including school closures, isolation requirements, social distancing, and cancelation of extracurricular activities, which independently or collectively may have shifted screen time patterns.

OBJECTIVE

To estimate changes in the duration, content, and context of screen time of children and adolescents by comparing estimates taken before the pandemic with those taken during the pandemic and to determine when and for whom screen time has increased the most.

DATA SOURCES

Electronic databases were searched between January 1, 2020, and March 5, 2022, including MEDLINE, Embase, PsycINFO, and the Cochrane Central Register of Controlled Trials. A total of 2474 nonduplicate records were retrieved.

STUDY SELECTION

Study inclusion criteria were reported changes in the duration (minutes per day) of screen time before and during the pandemic; children, adolescents, and young adults (≤18 years); longitudinal or retrospective estimates; peer reviewed; and published in English.

DATA EXTRACTION AND SYNTHESIS

A total of 136 articles underwent full-text review. Data were analyzed from April 6, 2022, to May 5, 2022, with a random-effects meta-analysis.

MAIN OUTCOMES AND MEASURES

Change in daily screen time comparing estimates taken before vs during the COVID-19 pandemic.

RESULTS

The meta-analysis included 46 studies (146 effect sizes; 29 017 children; 57% male; and mean [SD] age, 9 [4.1] years) revealed that, from a baseline prepandemic value of 162 min/d (2.7 h/d), during the pandemic there was an increase in screen time of 84 min/d (1.4 h/d), representing a 52% increase. Increases were particularly marked for individuals aged 12 to 18 years (k [number of sample estimates] = 26; 110 min/d) and for device type (handheld devices [k = 20; 44 min/d] and personal computers [k = 13; 46 min/d]). Moderator analyses showed that increases were possibly larger in retrospective (k = 36; 116 min/d) vs longitudinal (k = 51; 65 min/d) studies. Mean increases were observed in samples examining both recreational screen time alone (k = 54; 84 min/d) and total daily screen time combining recreational and educational use (k = 33; 68 min/d).

CONCLUSIONS AND RELEVANCE

The COVID-19 pandemic has led to considerable disruptions in the lives and routines of children, adolescents, and families, which is likely associated with increased levels of screen time. Findings suggest that when interacting with children and caregivers, practitioners should place a critical focus on promoting healthy device habits, which can include moderating daily use; choosing age-appropriate programs; promoting device-free time, sleep, and physical activity; and encouraging children to use screens as a creative outlet or a means to meaningfully connect with others.

Effects of remote learning during the COVID-19 lockdown on children's visual health: a systematic review

OBJECTIVES

Increased exposure to digital devices as part of online classes increases susceptibility to visual impairments, particularly among school students taught using e-learning strategies. This study aimed to identify the impact of remote learning during the COVID-19 lockdown on children's visual health.

DESIGN

Systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

DATA SOURCES

Scopus, PubMed and ScienceDirect databases from the year 2020 onwards.

ELIGIBILITY CRITERIA

We included cross-sectional, case-control, cohort studies, case series and case reports, published in English, Spanish or French, that approached the effects of remote learning during the COVID-19 lockdown on visual health in neurotypical children.

DATA EXTRACTION AND SYNTHESIS

We included a total of 21 articles with previous quality assessments using the Joanna Briggs checklist. Risk of bias assessment was applied using the National Institutes of Health quality assessment tool for before-and-after studies with no control group; the tool developed by Hoy et al to assess cross-sectional studies; the Murad et al tool to evaluate the methodological quality of case reports and case series; and the Newcastle-Ottawa Scale for cohort studies.

RESULTS

All but one study reported a deleterious impact of the COVID-19 lockdown on visual health in children. Overall, the most frequently identified ocular effects were refractive errors, accommodation disturbances and visual symptoms such as dry eye and asthenopia.

CONCLUSIONS

Increased dependence on digital devices for online classes has either induced or exacerbated visual disturbances, such as rapid progression of myopia, dry eye and visual fatigue symptoms, and vergence and accommodation disturbances, in children who engaged in remote learning during the COVID-19 lockdown.

PROSPERO REGISTRATION NUMBER

CRD42022307107.

The Impact of the COVID-19 Pandemic on Myopia Progression in Children: A Systematic Review

Myopia is the most common refractive error among children. The coronavirus disease 2019 (COVID-19) pandemic has affected children's health in many ways. Policy changes due to the COVID-19 pandemic, such as home quarantine and online schooling, have been proposed as causes for the increased risk of myopia progression. During strict home quarantine, children spend less time outdoors and more time using electronic devices which are important risk factors associated with myopia. Our systematic review aims to assess the relationship between myopia progression and these risk factors in children. We did the literature search from PubMed, Google Scholar, and ScienceDirect. A total of 10 research papers were selected for final review using the Preferred Reporting Item for Systematic Review and Meta-Analyses (PRISMA) guidelines. The research articles used had a quality of more than 70%. The quality of these articles was determined using the Joanna Briggs Institute (JBI) tool. Our review included eight cross-sectional and two cohort studies. Most of these studies used questionnaires to assess the risk factors of myopia. Standardized ocular examinations were done in most studies to measure visual acuity, spherical equivalent, and axial lengths. Our study found that the progression of myopia was affected by the reduced time spent outdoors and increased screen time during the pandemic. We also found that children's increased use of electronic devices, such as mobile phones and tablets, has significantly affected myopia progression during the pandemic.

Coronavirus disease 2019 outbreak and associated public health measures increase the progression of myopia among children and adolescents: Evidence synthesis

Purpose

Although studies have suggested that the coronavirus disease 2019 (COVID‐19) outbreak increased myopia progression, they had different settings and analysis methods. This study compared myopia progression before and during the COVID‐19 outbreak using meta‐analysis.

Methods

Relevant literature was searched on EMBASE, PubMed, ClinEpiDB and Web of Science and reviewed until 8 October 2021. The Newcastle–Ottawa Scale was used to evaluate the quality of the original studies. The mean difference of change in spherical equivalent refraction (SER) was used for evaluation before and during the COVID‐19 pandemic.

Results

The meta‐analysis included eight studies with 773, 797 individuals aged 5–18 years. Pooled analysis indicated that the mean difference of annual myopia progression during the pandemic was 0.41 D higher (95% confidence interval [CI]: 0.35–0.48, p < 0.01) than before the pandemic. Subgroup analysis using cycloplegic (mean difference, 0.30 D; 95% CI, 0.22–0.38; p < 0.01) or noncycloplegic refraction (mean difference, 0.60 D; 95% CI, 0.27–0.93; p < 0.01) indicated that the mean difference of annual myopia progression during COVID‐19 significantly increased in both refractive measurements.

Conclusion

Our findings demonstrated that the COVID‐19 pandemic accelerated myopic progression compared to the past. Government policies are urgently required to prevent and control myopia progression.

The Impact of Study-at-Home During the COVID-19 Pandemic on Myopia Progression in Chinese Children

Background: To assess the impact of study-at-home during the COVID-19 pandemic on myopia development in Chinese schoolchildren. Methods: This historical cohort involved two groups with a total of 154 children. The exposed group was formed from 77 children aged 8 to 10 years who studied at home in the 7-month period during the COVID-19 pandemic (follow-up period: January - August 2020) and did not study at home in the 7-month period before the COVID-19 outbreak (baseline period: July 2019 - January 2020). Seventy-seven children who did not undergo study-at-home (baseline period: 7 months in 2015, follow-up period: 7 months in 2016) were included in the control group. Cycloplegic refraction, axial length and uncorrected visual acuity were measured 3 times. The questionnaire mainly focused on collecting visual habits. Results: Myopia progression was similar between the two groups in the baseline period. However, in the follow-up period the exposed group had a greater change in refraction toward myopia (-0.83 ± 0.56 D) than the control group (-0.28 ± 0.54 D; p < 0.001). In addition, the exposed group exhibited a significantly greater change in refraction toward myopia in the follow-up period (-0.83 ± 0.56 D) than in the baseline period (-0.33 ± 0.46 D; p < 0.001). Difference-in-difference analysis indicated that study-at-home accelerated the change in refraction toward myopia (t = -0.567; p < 0.001). Conclusions: During the COVID-19 pandemic study-at-home accelerated the change of refraction toward myopia in children.