Progression in refractive error in children during COVID-19 pandemic due to virtual classes: A cohort study

Shovna Dash; Gayatree Mohanty; Soumya Kanta Mohanty; Nirmal Kumar Mohakud

doi:10.4103/cmi.cmi_108_22

ORIGINAL ARTICLE

Year : 2023 | Volume : 21 | Issue : 2 | Page : 110-113

Progression in refractive error in children during COVID-19 pandemic due to virtual classes: A cohort study

Shovna Dash¹, Gayatree Mohanty¹, Soumya Kanta Mohanty¹, Nirmal Kumar Mohakud²
¹ Department of Ophthalmology, Kalinga Institute of Medical Sciences, KIIT Deemed to be University, Bhubaneswar, Odisha, India
² Department of Pediatrics, Kalinga Institute of Medical Sciences, KIIT Deemed to be University; Department of Biotechnology, School of Biotechnology, KIIT Deemed to be University, Bhubaneswar, Odisha, India

Date of Submission	29-Sep-2022
Date of Decision	09-Dec-2022
Date of Acceptance	13-Dec-2022
Date of Web Publication	07-Apr-2023

Correspondence Address:
Prof. Nirmal Kumar Mohakud
Department of Pediatrics, Kalinga Institute of Medical Sciences, KIIT Deemed to be University, Bhubaneswar - 751 024, Odisha
India

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/cmi.cmi_108_22

Abstract

Background: The pandemic resulted in increased screen hours in children due to virtual education. The rate of progression of myopia was noticed to be remarkable in the past 2 years. This study is an endeavor to study the effect of increased screen hours during COVID home confinement on the degree of progression of myopia in school children and to evaluate the difference in change of refractive errors with a variation in the screen size of the digital device used. Methods: This was prospective observational study with a retrospective comparison arm, wherein 70 school children (140 eyes) aged 4–18 years were subjected to a cycloplegic refraction test. The difference in spherical equivalent refraction from the year 2018 to 19 was compared with that of the difference observed in the pandemic year 2019–2020. A statistical analysis was also made regarding the correlation of variation in refraction between the different genders, age groups, and screen sizes. Results: Of the 70 children, 29 (41.42%) were girls and 41 (58.58%) were boys. The gadgets being used vary from mobiles to laptops, and the range of screens and sizes varies from 100 cm² to 500 cm². Similarly, the duration of device use varied from 4 to 8 h. For 2018, the mean value of the spherical equivalent was −1.69 ± 1.42, for 2019 it was −1.92 ± 1.50 and for 2020 the mean value was −2.61 ± 1.47 for the right eye. The mean value of the spherical equivalent for the left eye in 2018 was −1.68 ± 1.51, in 2019 the value was −1.87 ± 1.58, and in 2020, the mean value was −2.73 ± 1.78. Conclusions: Increased exposure to digital devices during the COVID-19 period has a role to play in the progression of myopia in school-aged children.

Keywords: COVID-19, digital device, myopia, school children

How to cite this article:
Dash S, Mohanty G, Mohanty SK, Mohakud NK. Progression in refractive error in children during COVID-19 pandemic due to virtual classes: A cohort study. Curr Med Issues 2023;21:110-3

How to cite this URL:
Dash S, Mohanty G, Mohanty SK, Mohakud NK. Progression in refractive error in children during COVID-19 pandemic due to virtual classes: A cohort study. Curr Med Issues [serial online] 2023 [cited 2023 Jun 4];21:110-3. Available from: https://www.cmijournal.org/text.asp?2023/21/2/110/373753

Introduction

The prolonged lockdown during the pandemic resulted in a drastic lifestyle change. Indoor confinement with virtual education, coding-decoding, and many other digital platforms for education and entertainment have been noticed to have a significant effect on the progression of myopia.

Multiple studies in the past have made an effort to study the rate of progression of refractive errors. Many studies have identified a decrease in the time spent on outdoor activities as a leading risk factor in the development of myopia.^[1],[2],[3] Similarly, other factors studied over the years and known to be associated with the progression of myopia, are the duration and intensity of near work.^[4]

Our study aims to review if the progression of myopia is rapid with enhanced use of digital devices and to study if there is any significant association between the screen size and the degree of progression of myopia.

Methods

Design

This was a prospective, observational study with a retrospective comparison arm.

Study setting and period

This study was conducted in the Department of Ophthalmology, Kalinga Institute of Medical Sciences, a tertiary care teaching hospital, Bhubaneswar, Odisha, from August 2018 to September 2021.

Study participants

Seventy school age children (4–18 years of age), who have been prescribed spectacles for correction of refractive errors, and currently using digital gadgets for academic activities were enrolled. Children with any organic ocular pathology and a family history of pathological refractive errors were excluded from the study. Children <4 years old did not get to start school because of COVID-19 were not included. Furthermore, those students whose 2018 and 2019 cycloplegic refractive corrections were not available for comparison were excluded from the study. After a written informed consent as per the Declaration of Helsinki, and an ethical clearance, a thorough ocular examination and cycloplegic refraction were done and data were collected on a preformed datasheet. Parents were also assigned a questionnaire documenting the hours of use and the type of digital device being used, as well as the hours of outdoor activity of the child. Other ocular complaints, such as asthenopia, dryness, if any, were also documented and a thorough evaluation was done.

Outcome measures

The progression in spherical equivalent refractive errors over 3 years.

Statistical analysis

Data were presented as mean ± standard deviation for the continuous data and the means of spherical equivalent over the periods were compared using the ANOVA for continuous data. We have taken the spherical equivalent values for both right and left eyes from the year 2018 to 2020 and analyzed them with different groups such as age, sex, and screen sizes of the various digital devices used. The statistical software SPSS software version 23.0 (IBM Corp., Redmond, WA) was used to analyze the data, and the P < 0.05 was considered statistically significant. Thereafter, a comparison between the change in spherical equivalent refraction over the years 2018–19, 2019–20, and 2020–21was done. A comparative analysis was also done between the two genders and the varying screen sizes. Similarly, an evaluation was done between the different age groups, the groups being 4–8 years, 9–13 years, and 14–18 years.

Results

Of the 70 children included in the study, 29 (41.42%) were girls and 41 (58.58%) were boys. A total of 140 eyes were included in the analysis.

The gadgets being used vary from mobiles to laptops, and the range of screens and sizes varies from 100 cm² to 500 cm². Similarly, the duration of device use varied from 4 to 8 h. A comparative analysis was done to find out if there was a significant association between the screen size and the degree of progression of myopia.

For 2018, the mean value of the spherical equivalent was −1.69 ± 1.42, for 2019, it was −1.92 ± 1.50, and for 2020, the mean value was −2.61 ± 1.47 for the right eye. The mean value of the spherical equivalent for the left eye in 2018 was −1.68 ± 1.51, in 2019 the value was − 1.87 ± 1.58, and in 2020, the mean value was −2.73 ± 1.78. A significant myopic shift was noticed between the 3 years, with an inter-group difference being significant with a P = 0.001 in both eyes [Table 1].

Table 1: Mean spherical equivalent refractive power in both eyes and the inter-group comparison over a period of 3 years

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After noticing a significant change in the spherical equivalent for both the eyes, we run a post hoc analysis to see in which year exactly the difference occurred. There was significant difference in the mean spherical equivalent of the right eye between 2018 and 2020 (P < 0.001) and from 2019 to 2020 (P < 0.017). Furthermore, the difference is significant for the spherical equivalent of the left eye between 2018 and 2020 (P < 0.001) and from 2019 to 2020 (P < 0.006). However, the difference between 2018 and 2019 was not significant in either of the right eye (P = 0.637) or the left eye (P = 0.761) [Table 2].

Table 2: Inter-group difference in spherical equivalent and their statistical significance between different years

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From 2019 to 2020, the use of mobiles and computers increased significantly for online classes and otherwise; hence, the increase in the spherical equivalent of both eyes can be associated with the increased screen use. A comparison of the change in spherical equivalent refraction between the different age groups did not reveal any significant difference. Similarly, a positive correlation was found neither with a difference in screen size [Table 3] nor between the two genders. Convergence insufficiency was not found in any of the included subjects. Symptoms such as asthenopia, a burning sensation accompanied by signs of ocular xerosis were found in negligible subjects.

Table 3: Inter-group comparison and significance in progression of refractive errors amongst different gadgets

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Discussion

A significant myopic shift was noticed in 2020 compared to 2018–2019 among children using digital devices for classes. Our observation in this study adds to and strengthens the existing findings of the progression of myopia in children resulting in increased exposure to the digital screen during the COVID-19 lockdown.

To control the COVID pandemic, a strict lockdown was imposed to curb the spread of infection. Our country saw stringent home confinement, where virtual teaching was the only mode of education possible, from March 2020, followed by a phased unlock in September. However, 6 months later, educational institutions were opened only for students from 15 to 18 years of age.

No doubt that it did help control the morbidity and mortality due to COVID, but with a limitation in the mobility of people, a surge has been noted in obesity, diabetes, and myopia alike.^[1] What we found was a lot many new cases of myopia, as well as a rapid progression of preexisting myopia.

Multiple studies in the past have made an effort to study the rate of progression of refractive errors. Many a study has identified a decrease in the time spent in outdoor activities as a leading risk factor in the development of myopia.^[2],[3],[4] Similarly, other factors which have been studied over the years to be associated with the progression of myopia are the duration and intensity of near work.^[5]

The most fragile population susceptible to development and a rapid progression of myopia are school children. They are in the critical phase of ocular development.^[6] While multiple factors, besides genetic susceptibility, have been postulated to have a role in myopia progression, increased exposure to screen time has been documented in several studies to be an aggravating factor.^[7],[8],[9] However, certain other studies did not find a significant correlation.^[10] This discrepancy might lie in the sample size and the assessment of screen exposure and refractive error. It has also been postulated that increased screen time may lead to myopia progression consequent to an accommodative spasm.^[11]

Similarly, it has been documented that younger children and the male gender had a lower risk of myopia progression during the COVID lockdown.^[11] However, the difference in progression between the different age groups and sex was not statistically significant in our study.

A significantly less progression in children using a larger screen-like laptop as compared to mobiles has been noticed in a few studies.^[12] In our study, we did not find any such significant difference between the use of different screen sizes.

At the same time, routine refraction is advisable in school children. Due to the apprehension and limitation of movement during this COVID pandemic, a delay in routine refraction has been noted, and the effect of the same needs to be studied. Unnecessary use of digital devices for play, which besides aggravating myopia, may lead to other ocular ailments, such as dry eye disease and keratoconus. Many a parent reported the use of digital devices for much more time than school hours. This combined with a delay in vision screening has heightened the burden of myopia. Hence, the need of a thorough evaluation and counseling regarding the limitation of screen time.

In this pandemic era, indoor confinement and a resultant decrease in sunlight exposure has led to a rise in rickets.^[13] The same factor has also been postulated as an aggravating factor in myopia progression. Outdoor time has been seen to be a shielding factor against the advancement of myopia, the underlying reason being an association between sunlight exposure and dopamine levels.^[2],[14]

Although virtual education was inevitable, even now, with the increased use of digital devices, the only way to control this progression is vigilance and knowledge amongst parents and children alike, about limiting the hours of screen use to very essential. Similarly, increasing the distance between the eyes and the screen, blinking at frequent intervals, and following the 20-20-20 rule of screen use, that is looking at a distance 20 feet away for 20 s, after every 20 min of computer use, would be highly beneficial for children at their tender age. Alongside should go a constant use of glasses and a routine refraction every 6 months. Parents can also ensure healthy eyes for their kids with a healthy lifestyle and diet and regular exposure to sunlight and outdoor activities, all while keeping in mind the COVID-appropriate behavior.

Children are the future of this ever-widening world. While home confinement for safety was the requirement of the hour, with new waves of variant strains of omicron coming up, the end to this pandemic seems nowhere soon. This confinement is leading to a retardation of the holistic growth of a child-be physical, social, intellectual, or emotional. Myopia today may lead to multiple ocular complications like glaucoma tomorrow and school performance may also be hampered.^[15] Implementation of a regular school eye screening at every school and early referral for refractive correction is the need of the hour. Besides, education regarding refractive errors, regular use of glasses, and the use of digital devices, ought to be provided for students as a part of their school curriculum.

Limitations

With the COVID scare still high, we had very few students coming for repeat refraction and hence a small sample size, which is a limitation of our study. For an in-depth evaluation of certain factors like the total number of hours spent on digital devices and outdoor exposure, we need a larger sample, and an individual analysis of factors can be done if confounders are eliminated from the study. Distance between the gadget and the eyes could not be commented upon due to a lack of continuous scrutiny by parents. With positive findings in our study, we intend to continue this study on a larger sample.

Conclusions

Increased exposure to digital devices during COVID-19 period leads to the progression of myopia in school-aged children. A confirmatory opinion about the effect of screen size can be given with a larger study sample.

Acknowledgment

We are thankful to the department of ophthalmology and pediatrics for providing the platform to conduct the study. We pay our gratitude to Mrs. Subhadra Priyadarshini and Mr Saurav Padhee biostatisticians for their help in analysis of the data.

Ethical statement

Approval from the Institutional Ethics Committee of KIMS (KIIT/KIMS/IEC/656/2021) was obtained prior to the commencement of the study.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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