Impact of online classes on eye health of children and young adults in the setting of COVID-19 pandemic: A hospital-based survey

Abstract

BACKGROUND:

To analyze the impact of online classes on eye health of children and young adults during the COVID-19 pandemic.

MATERIALS AND METHODS:

An observational study with a written questionnaire and comprehensive ophthalmic evaluation at a tertiary eye care center in South India, during the COVID-19 pandemic.

RESULTS:

Of the 496 patients, most were 5–10 years old, attending online classes 1–2 h/day with majority (84.7%) having <4 h of classes. Electronic gadget use after classes was seen in 95.6% participants and 28.6% admitted to using it for more than 2 h/day. Digital eye strain (DES) was seen in 50.8% of patients of which headache or eye ache were the most common symptom (30.8%). Duration of online class was found to be the single most independent factor associated with the development of eye complaints (P = 0.001). Duration of class hours (P = 0.007) and light setting (P = 0.008) was found to be independent determinants of developing DES.

CONCLUSIONS:

Increased screen time, inadequate light setting, and excessive application of near vision can produce undesirable effects including the development of DES, worsening or development of new refractive errors and squint.

Introduction

The education system in India is facing a new crisis due to the COVID-19 pandemic caused by the novel coronavirus SARS-CoV2. In the 2^nd week of March 2020, state governments across the country began shutting down schools and colleges temporarily as a measure to contain the spread of the novel coronavirus.[1] A total of 320 million learners in India have been adversely affected by the pandemic and had to transition to e-learning. This unexpected shift to e-learning has led to the development of many health problems in the students including weight gain, sleep disruption, and psychosocial stress.[2] The dependence on gadgets has worsened during the pandemic and raised concerns of negative effects on students eye health like computer vision syndrome (CVS) and increased risk of myopia.[3] Even though the Ministry of Human Resource Development.[4] The government of India has recommended only 30 min of screen time for preprimary students, two classes of 45 min each for classes one to eight, and four classes of 45 min each for classes 9–12 per day, these guidelines are not usually strictly adhered to by all.

CVS, also referred to as digital eye strain (DES) encompasses a range of ocular and visual symptoms that result from prolonged use of computers, tablets, e-readers, and cell phones. The prevalence of this condition may be 50% or more among computer users.[5] Symptoms fall into two main categories: Those linked to accommodative or binocular vision stress, and external symptoms linked to dry eye. Kozeis found that viewing computer screens regularly can lead to eye discomfort, blurred vision, fatigue, headaches, and other symptoms.[6] Zhang et al. observed that the time spent in an e-learning environment significantly affected visual acuity in both eyes of elementary school students in China.[7]

Ever since the country-wide lockdown due to COVID-19 began in India, we saw a substantial increase in children and young adults with complaints of blurring of vision, dry eye, headache, and diplopia attending the outpatient services of pediatric ophthalmology and strabismus department of our hospital. This prompted us to devise this questionnaire-based survey.

Purpose

To analyze the impact of online classes (e-learning) on the eye health of children and young adults in the setting of COVID-19 pandemic.

Materials and Methods

This was an observational study based on a written questionnaire provided to all children and young adults attending online classes attending the outpatient services of paediatric ophthalmology and strabismus department in a tertiary eye care center in South India, from August 2020 to January 2021 during the COVID-19 pandemic. The patients or their parents/caregivers were asked to fill in a written questionnaire [Table 1] regarding details of online classes including duration, mode, working distance, lighting, break between classes and any eye complaints due to them. They were also asked to indicate if they used electronic gadgets after online classes and if so, the nature and duration of use. All participants underwent comprehensive eye evaluation including assessment of vision, refraction, binocular status, slit lamp and fundus examination. The presence of refractive error, squint, worsening of refractive error or squint or new onset refractive error or squint were also noted. The study was conducted in accordance with the Declaration of Helsinki and was approved by the institutional review board and ethics committee. Statistical analysis of risk factors was done using univariate and multivariate logistic regression analysis. In the univariate analysis, the Chi-square test was used to investigate the associations between the qualitative variables. In the multivariate analysis, multiple logistic regression analysis was performed to identify the independent risk factors by calculating the odds ratios and their corresponding 95% confidence interval. P < 0.05 was considered statistically significant.

Table 1:

Questionnaire

Name: ___________ Age: ___________ Sex: ___________ Class/grade: ___________ MRD: ___________ 1. Are you attending online classes? Yes □ No □ 2. How many hours of class do you have? 1-2 hours □ 2-3 hours □ 3-4 hours □ >4 hours □ 3. Do you get any break in between classes? Yes □ No □ 4. If so, duration of break 15 min □ 15-30 min □ >30 min □ 5. Type of electronic device/gadget used for online classes Mobile □ Tablet □ Laptop/desktop □ TV □ 5. At what distance do you keep the device while attending class? <1 feet □ 1 feet □ 2 feet □ >2 feet □ 6. Light setting in the room while attending class Dim □ Spot □ Adequate □ 7. Do you use spectacles for vision Yes □ No □ 8. Have you experienced any eye related problem while attending online class? Yes □ No □ 9. If yes, what was your difficulty     a. Headache/eye ache □     b. Watering/blinking/itching/burning sensation □     c. Blurry vision □     d. Diplopia and difficulty in focus □     e. Difficulty to see with your present spectacle □     g. Others-please mention the complaint_______ 10. Do you use mobile/other gadgets even after your online class is over? Yes □ No □ 11. Total hours of using gadgets/day other than online classes? <1 hour □ 1 hour □ 1-2 hours □ >2 hours □ 12. At the end of the day, do you experience any eye related problems Yes □ No □

Inclusion criteria

Children (5–18 years) and young adults (18–25 years) attending online classes, coming to the pediatric ophthalmology and strabismus department, of a tertiary eye care center in South India, from August 2020 to January 2021; who answered a written questionnaire regarding online classes and eye complaints and who underwent a comprehensive eye evaluation.

Exclusion criteria

Those who did not give consent or were unable to complete the questionnaire, those with trauma and who underwent eye surgery were excluded.

Results

There were 496 patients included in the study. The mean age was 10.49 years (standard deviation: 3.83). Majority were in the 5–10 years of age group (44.9%) and in the 10–15 years of age group (40.1%) [Figure 1]. The youngest participant was 5 years old and oldest was 23 years. There was a slight female preponderance (females 52.8%, males 47.2%). 51.8% had 1–2 h, 20.8% had 2–3 h, 12.1% had 3–4 h, and 14.7% had more than 4 h of online classes in a day [Figure 2]. Majority (42.5%) used tablets, 29.2% used laptops, 20.2% used mobiles, and 7.9% used television for online classes [Figure 3]. There was a break in between each class for 84.3% of participants, even though most (40.5%) had only a break of 15 min. Majority (42.7%) used the electronic gadget at a working distance of one foot, 29.2% at two feet, 20.2% at <1 foot and 7.9% at more than two feet. Most (76.2%) used ambient light, 23% spotlight and 0.8% dim light during the classes. Electronic gadgets were used by 95.6% of participants even after classes and 28.6% admitted to using it for more than 2 h per day mainly for internet surfing and playing games. Eye complaints were seen in 50.8% of participants, of which head ache or eye ache was most common (30.8%), followed by watering and excessive blinking (17.7%), difficulty in vision (14.9%) and double vision or difficulty in adjusting focus (9.9%) [Figure 4].

Figure 1:

Age distribution

Figure 2:

Duration of online classes

Figure 3:

Mode of class

Figure 4:

Distribution of eye complaints

Statistical analysis by Chi-square test revealed that duration of online class (P = 0.001) was the single most independent factor with a significant association of developing eye complaints [Table 2]. Univariate analysis revealed that more than 2 h of online classes had a 2.55 times increased likelihood of eye complaints and this increased to 3.28 times with more than 4 h of online classes [Table 3]. The likelihood of headache/eye ache was 2.13 times with more than 2 h of online classes and 3.19 times with more than 4 h of online classes. More than 2 h of online classes also increased the risk of complaints of difficulty in vision to 2.4 times and this increased to 2.6 times with more than 4 h of online classes. Complaints of watering and excessive blinking increased with the duration of online classes and in dim or spotlight as compared to ambient lighting [Tables 4,5,6]. On multivariate logistic regression analysis, duration of class hours (P = 0.007) and light setting (P = 0.008) were found to be independent determinants of watering and excessive blinking [Table 5]. Subjects with duration of class hours more than 2 h were 1.91 times at higher risk of developing watering compared to those with less class hours [Table 5]. Subjects who used dim or spotlighting were 1.98 times at higher risk of getting watering compared to those who used ambient light setting [Table 5]. Children with more than 2 h class duration in age group <10 years, seemed to have 2.062 times risk of DES, compared to those with less hours of classes. In the >10 years age group, we found that the risk of DES increased to 2.04 with >4 h of classes [Tables 7 and 8]. Other factors such as mode of class, working distance, and break time were not found to have statistical significance.

Table 2:

Eye complaints and duration of class hours

Class hours	Eye complaints				P
	No	Yes	Data missing	Total
1-2	149	103	5	257	0.001**
2-3	42	61	0	103
3-4	21	39	0	60
>4	22	50	1	73
Missing	2	0	1	3
Total	236	253	7	496

**P value <0.05 was considered statistically significant

Table 3:

Determinants of eye complaints: Univariate analysis

Determinant	Level (h)	Yes	No	Missing	OR (95% CI)	P
Duration of class (h)	2-3	61	42	0	2.101 (1.317-3.349)	0.0018**
	3-4	39	21	0	2.686 (1.493-4.831)	0.0010**
	>4	50	22	1	3.287 (1.876-5.760)	0.0001**
	1-2	103	149	5
	Missing	0	2	1
Total	496	253	236	7

**P value <0.05 was considered statistically significant. CI: Confidence interval, OR: Odds ratio

Table 4:

Watering versus duration of class hours

Duration of class (h)	Watering			P
	No	Yes	Total
1-2	223	34	257	0.005**
2-3	86	17	103
3-4	43	17	60
>4	53	20	73
Missing	3	0	3
Total	408	88	496

**P value <0.05 was considered statistically significant

Table 5:

Determinants of watering-multivariate logistic regression analysis

Determinant	Level	Yes	No	OR (95% CI)	P
Duration of	>2	54	182	1.918 (1.192-3.084)	0.007**
class (h)	1-2	34	223
	Missing	0	3
Light setting	Dim/spot	31	87	1.983 (1.199-3.277)	0.008**
	Ambient	57	321

**P value <0.05 was considered statistically significant. CI: Confidence interval, OR: Odds ratio

Table 6:

Watering, duration of classes, lighting: Univariate analysis

Determinant	Level	Yes	No	Total	OR (95% CI)	P
Duration of class (h)	2-3	17	86	496	1.296 (0.688-2.442)	0.4215
	3-4	17	43		2.593 (1.330-5.054)	0.0051**
	>4	20	53		2.475 (1.320-4.639)	0.0047**
	1-2	34	223
	Missing	0	3
Light setting	Dim/spot	31	87	496	2.007 (1.220-3.300)	0.006**
	Ambient	57	321

**P value <0.05 was considered statistically significant. CI: Confidence interval, OR: Odds ratio

Table 7:

Determinants of digital eye strain in age group<10 years: Univariate analysis

Determinant	Level (h)	Yes	No	Missing	OR (95% CI)	P
Duration of class	>2	41	30	0	2.062 (1.161-3.662)	0.014**
	<2	59	89	3
	Missing	0	1	0

**P value <0.05 was considered statistically significant. CI: Confidence interval, OR: Odds ratio

Table 8:

Determinants of digital eye strain in age group>10 years: Univariate analysis

Determinant	Level (h)	Yes	No	Missing	OR (95% CI)	P
Duration of class	>4	42	18	1	2.039 (1.102-3.774)	0.023**
	<4	111	97	2
	Missing	0	1	1

**Significant association. P value is calculated using Chi-square test. CI: Confidence interval, OR: Odds ratio

Preexisting refractive error [Figure 5] was observed in 72% of study patients (possibly because of this being a hospital-based survey); of which compound myopic astigmatism (43.95%) was most common, followed by simple myopic astigmatism (35.5%). Preexisting strabismus was seen in 22.78% of patients. Worsening of refractive error was noted in 52% and worsening of strabismus seen in 10.1%, respectively. New refractive error was observed in 15.3% and new strabismus in 12.4% of patients. Among the newly detected refractive errors, simple myopic astigmatism was the most common (56.2%), followed by compound myopic astigmatism (28.8%). Among the newly developed strabismus, majority (81.25%) were symptomatic esotropias with diplopia, compared to exotropia (18.75%) and were observed in participants who had more than 4 h of screen time.

Figure 5:

Distribution of preexisting refractive error

Discussion

Of the 451 million monthly active users in India, 66 million are in the age bracket of 5–11 years, who access Internet on devices of family members, as per an IAMAI report titled, “India Internet 2019.”[8] Palaiologou reported that 68% of European children regularly used computers and 54% undertook online activities.[9] As per a study conducted in rural western India, the average time spent in front of a screen among children was approximately 2.7 ± 1.7 h.[10] In a study which looked at the usage of social media devices, applications, parental knowledge and involvement among Abu Dhabi children, Badri et al., reported that the average time spent on social media by students was 5.2 h per day.[11] Rafeeq et al. reported that the proportion of CVS among individuals who were using visual display terminal for more than 2 h was significantly higher in adolescents compared to adults.[12]

DES,[5] also known as CVS, encompasses a range of ocular and visual symptoms which fall into two main categories: Those linked to accommodative or binocular vision stress, and external symptoms linked to dry eye. Although symptoms are typically transient, they may be frequent and persistent, and bothersome. DES may be identified and measured using one of several available questionnaires, or objective evaluations of parameters such as critical flicker–fusion frequency, blink rate, and completeness. Accommodative function and pupil characteristics may be used to provide indices of visual fatigue. Correlations between objective and subjective measures are not always apparent. A range of management approaches exists for DES including correction of refractive error, management of dry eye, incorporating regular screen breaks, and consideration of vergence and accommodative problems. Portello et al. also identified a clear split of computer-related symptoms into two categories, those associated with accommodation (blurred vision at near, blurred distance vision after computer use and difficulty refocusing from one distance to another) and those that seemed linked to dry eye (irritated/burning eyes), eyestrain, headache, tired eyes, and sensitivity to bright light.[13] Moon et al. noted that smartphone use was an important risk factor for dry eye disease in children and recommended close observation and caution regarding video display terminal use.[14] In our study too, 50.8% had eye complaints which pertained to DES, of which headache or eye ache was most common (30.8%), followed by watering and excessive blinking (17.7%), difficulty in vision (14.9%), and double vision or difficulty in adjusting focus (9.9%).

In an open online survey conducted through social media platforms for 2 weeks, 93.6% of respondents reported an increase in their screen time since the lockdown.[15] With the education system itself shifting to the digital mode, parents are walking an emotional tightrope now, stuck between the educational demands of their children and the need to take care of their well-being. Even though the majority in our study were in the 5–10 year age group and were attending online classes of 1–2 h a day only, 95.6% used electronic gadgets even after classes and 28.6% admitted to usage for more than 2 h per day. This was comparable to a study done in the United Kingdom, in which the participants spent approximately 4 h per day on digital devices.[9] We found that the duration of online class was the single most independent factor with a significant association with developing eye complaints. More than 2 h of online classes had a 2.55 times increased likelihood of eye complaints and this increased to 3.28 times with more than 4 h of online classes. The likelihood of DES also increased with increasing time of online class. Multivariate logistic regression analysis proved that duration of class hours and light setting were found to be independent determinants of DES. Subjects with the duration of class hours more than 2 h were 1.91 times are at higher risk of developing watering and excessive blinking compared to those with less class hours. Subjects who used dim/spot illumination were 1.98 times at higher risk of getting DES compared to those with ambient light setting. Other factors such as mode of class, working distance, and break time were not found to have statistical significance. Worsening of refractive error and worsening of strabismus were seen in 52% and 10.1% of participants, respectively. New refractive error was observed in 15.3% and new strabismus in 12.4% of patients. Among newly developed strabismus, majority were symptomatic, had acute acquired comitant esotropias (81.25%) and were seen in those with more than 4 h of screen time. Excessive application of near vision leading to the development of acute acquired concomitant esotropia (AACE) has been reported by Lee et al.[16] and Vagge et al.[17] We also had thirteen subjects with acute onset diplopia and esodeviation which were diagnosed to be AACE and are currently under evaluation.

Prolonged school closure and home confinement during the current COVID-19 lockdown have ushered in lifestyle behavior changes including a significant increase in screen time[18] and raised serious concerns of worsening the global burden of myopia.[3] Apart from these, the excessive application of near vision may have other undesirable effects such as development of DES and AACE as seen in our study. Based on our findings, we would recommend not more than 2 h of online classes for children in the 5–10 years of age group and not more than 4 h of online classes for older children (10–15 years) and young adults. The classes should preferably be split into 3–4 sessions; each of 30–45 min duration with adequate breaks (15–20 min) in between. The light setting should be ambient rather than dim or spot illumination.

Shortcomings of our study would be lack of quantification of DES, hospital-based survey, short duration and lack of follow-up. Nevertheless, we feel it is a good reflection of the impact of e-learning on the eye health of students.

Conclusions

Increased screen time, inadequate light setting and excessive application of near vision can produce undesirable effects, including the development of DES, worsening or development of new refractive errors and squint. Regulating the duration of e-learning, reducing number of hours of screen time, ensuring adequate lighting, taking breaks, promoting healthy lifestyle habits like increasing outdoor play should be recommended to improve the eye health of students.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.