Increased digital screen time during COVID-19 may accelerate myopia epidemic
When the COVID-19 pandemic spread and governments worldwide enforced school closure as part of their containment strategy, digital technology and virtual learning played a vital role in ensuring some degree of class continuity.
As schools reopen, e-learning approaches will remain an important backup strategy for blended learning and in the event of new closures. Digital innovation is expected to have many positive outcomes in the future of education. However, there is concern among ophthalmologists that increased screen time, together with a significant reduction of the time spent outdoors, might further accelerate the myopia epidemic.
“There is a possibility that a prolonged battle against the COVID-19 virus may lead to an increase in the incidence of myopia by shaping long-term behavioral changes conducive for the onset and progression of myopia,” Chee Wai Wong, MD, and co-authors, wrote in a review paper published in American Journal of Ophthalmology.
However, the situation created by the pandemic could represent an opportunity to draw attention to the problem, according to OSN Pediatrics/Strabismus Board Member Jordana M. Smith, MD.
“As ophthalmologists, we have now an opportunity to raise awareness among parents and teachers and eventually engage with policy makers and curriculum developers to set up strategies for myopia mitigation that will help students also beyond the pandemic,” she said.
Evidence of increasing myopia
The rapid rise of myopia has been a concern in the past decade, reaching the highest peaks in East Asia, where more than 90% of teenagers and young adults are shortsighted. In the United States, prevalence has doubled, from 20% to 40%, in the past 3 decades.
The impact of near work on myopia has been elucidated by several studies. In their review and meta-analysis of studies in a large number of children, Huang and co-authors found that there is an evidence rating of II for recommending a reduction in time spent on near activities, including reading, watching TV, playing computer games and studying.
“The evidence for screen time alone is not conclusive since studies are few and mainly based on self-reported measurements of screen time, which may be strongly biased,” Wong said.
However, practitioners are going to learn more about this soon, according to OSN Pediatrics/Strabismus Board Member Rudolph S. Wagner, MD.
“In the U.S., the use of these devices is now widespread even in preschool age and has markedly increased during the pandemic. We can see trends now, but soon we are going to have a lot of data,” he said.
On the other hand, time spent outdoors has shown to be protective against the onset and progression of myopia.
“An over 50% decrease in the risk of myopia progression was shown in children who spend at least 11 hours outdoors per week,” Wagner said.
Increased screen time
School closure during the first stage of the pandemic brought the widespread adoption of online learning, a sudden change for which no one — teachers, students or parents — was prepared.
“Talking with parents, I have seen many approaches. Some schools were doing 1.5-hour courses, with 5-minute breaks in between, for 6 hours a day; some other schools were doing just a few 30-minute sessions alternated with worksheets. None of the programs had some mandatory outdoor activity time or physical education component, and there was a lot of reliance on laptops and tablets,” Smith said.
Reopening has taken place at different times and with various modalities of organization and timetabling, often alternating in-person instruction with blended online and independent learning. In response to the inevitable new local outbreaks or isolated clusters of positive cases, a fragmented school year is expected, in which partial or temporary closures may disrupt the normal classroom routine, reintroducing remote learning.
“In the school attended by my 16-year-old, there were too many cases, and so they closed the school and sent the students home with their iPad again for 2 weeks. My other two kids are still attending school regularly,” Erin D. Stahl, MD, an OSN Pediatrics/Strabismus Board Member, said.
Something she noticed is that her children have gotten into the habit of spending a lot more time playing video games on their phones.
“During lockdown, we tried to be great parents by organizing activities for them in and outside the house, and they do spend time outdoors, but when they come back home now, they end up on a screen. Therefore, I see it firsthand also as a parent that near screen time has increased significantly,” she said.
In their paper, Wong and co-authors differentiated between educational and recreational screen time.
“It is important to differentiate because educational screen time is, at this point in history, a necessary integration or substitute of in-presence school time, but recreational screen time is also on the increase because children have become familiarized with the use of digital devices. There is a risk that they might increasingly replace outdoor activities or even indoor non-digital recreational time with screen time,” Wong said.
Immediate and long-term consequences
As routine ophthalmology practices gradually restarted and parents brought in their children for appointments, many new complaints emerged regarding screen-related eye symptoms.
“It is too early to see the effects of increased screen time on vision, but parents reported their kids getting discomfort or pain while reading, headache and eye fatigue,” Wagner said.
Computer use affects blink rate, which in turn leads to symptomatic dry eye.
“Kids may not tell you, but then they start blinking incessantly after computer use and rubbing their eyes. When you read a book you move it around, turn the pages, and focusing is more variable. But when you use a computer, your distance and position don’t change, and your eyes are fixed on the screen. When you constantly focus on a particular distance, especially if you have an uncorrected refractive error, you probably will be focusing harder than you need to and for a prolonged period of time. This causes eye discomfort and muscle pain around the eyes,” he said.
According to a Common Sense Media report released in October 2019, the use of screens by children and teenagers in the United States was on average 5 hours per day in the 8- to 12-year-old age group, increasing to 7.5 hours in the 13- to 18-year-old age group. This was in pre-COVID-19 times and did not include school-related activities.
“This is a global problem, and we are worried that this further increase is not going to be temporary. We need close collaboration between parents, schools and governing bodies to mitigate the long-term collateral impact of COVID-19 policies. Myopia is not just a problem that can be corrected with glasses. As myopic children become older, complications may occur, such as myopic [choroidal neovascularization], glaucoma and retinal detachment. This is something we want to prevent,” Wong said.
Steps by parents and teachers
“At the moment I see and hear of children complaining of eye strain and headache, but for next year, I expect a boom of children needing prescriptions and a worsening in children who are already myopic,” Smith said.
Her advice to parents is to establish daily schedules for their children, minimizing recreational screen time when they are engaged for 3 hours or more with digital learning.
“I have been inviting them to hold off giving their kids the iPad to play if they have been using it for school. Free time should be away from screens, playing outside as much as possible, but also including non-digital indoor activities,” Smith said.
She has also been encouraging families to make the most of their home environment, so that during online learning kids can have good lighting conditions, with ways to use distance vision during breaks, such as looking out of a window.
Based on recommendations from the American Academy of Ophthalmology, screen time should include regular distance vision breaks, following the 20-20-20 rule: Every 20 minutes, look at something 20 feet away for 20 seconds.
“This allows you to rest your eyes. Further recommendations include proper positioning of the screen, do not bend your neck, and relax your neck and shoulders. Screen lighting should feel comfortable, not too bright and not too dim, and the computer should never be used in a dark room. Many of these recommendations are just common sense,” Wagner said.
The WHO and the American Academy of Pediatrics call for no screen time at all for children younger than 2 years and no more than 1 hour a day for children 2 to 5 years old, while no recommendations are given for older children and adolescents, who are in the age groups in which time spent on screens escalates exponentially. In the Family Media Use Plan, the AAP suggests that parents should negotiate limits and boundaries for screen time with older children.
“Having three kids in the older than 6 age group, I talk about high-quality vs. low-quality screen time. The digital world is expanding, and the new generations increasingly need to develop digital skills and competence, but kids spend a lot of low-quality screen time. We need to reduce the low-quality screen time and replace it with distance, possibly outdoor vision activities,” Stahl said.
Wong suggested “digital detox” as a method to encourage healthy digital device habits.
“There are in-device applications that allow parents to set limits, restricting the time of screen usage per day or per session. These applications are a simple method to let the users know how much time they spend on digital devices, reminding them to disconnect and get a rest in between digital screen usage,” he said.
Parents should also make an effort to supervise digital content and help their children develop their own ability to select, process and interpret information, thus optimizing and decreasing the overall time spent online.
“Teachers should collaborate with parents in doing this and in designing schedules where digital education and rest periods are alternated,” Wong said. “Remote learning does not require looking at a screen all the time but may include arts and crafts activities, distance activities, creative work and physical exercise.”
Beneficial effects of outdoor time
In China, Taiwan, Singapore and other Asian countries where the prevalence of myopia is the highest, governments have adopted intervention measures for myopia control that include specific amounts of outdoor activities within the school curriculum.
In Taiwanese schools, the Tian-Tian 120 program, implemented in 2010, encourages teachers to take children outdoors for 120 minutes every day. Within 5 years, the prevalence of myopia decreased continuously, reversing the trend of the previous decade. A similar program implemented across 12 primary schools in Guangzhou, China, led to equally positive results over 3 years with the addition of just 40 minutes of outdoor activity per day.
“The most well-established protective factor for myopia is outdoor time. In the current situation, the implementation and continuity of these programs in our schools is jeopardized, and social distancing may curtail outdoor activities also in the free time of children and adolescents,” Wong said.
Although the benefits have been scientifically proven, the mechanisms through which outdoor time prevents and slows down myopia have not yet been clarified.
“One likely explanation is that pupil constriction gives increased depth of focus, so you don’t need to accommodate as quickly as you would if you were indoors. The other is that light stimulates the release of dopamine from the retina, which may contribute to the inhibition of globe elongation,” Wagner said.
Unlike Asian countries, the United States has not implemented outdoor activity programs in schools, Smith said.
“We need more public health initiatives that include mandatory outdoor activities for our children and make educators aware of the increasing problem,” she said.
The pandemic might represent an opportunity in this respect, and Stahl already sees encouraging signs in the way school timetables are organized to include more time outdoors for safety.
“My kids are spending a little more time outdoors now than they did before because they are having mask breaks outdoors and they are eating outdoors. None of this was happening before, and maybe we are going to see an increase in meaningful, creative outdoor activities, which would be great,” she said.
What is lacking, however, is the awareness of how spending too much time focusing on close-up objects, including books, smartphones and computer screens, may affect vision for life, in a way that goes beyond the need for a pair of spectacles.
“I have never encountered a layperson who heard about myopia prevalence or myopia control. There is very little information here in the U.S., and when the media talk about screen time, they focus on the impact on overall development, not specifically on myopia. There are plenty of resources on the web, but the initial introduction to the problem, the wake-up call that makes you curious to read and know more, has not been sent,” Stahl said.
Recently, she has noticed a shift in the attitude of ophthalmologists, who have gradually started to recognize that the myopia boom is a reality, with steps needed to control this rampant escalation.
“Optometrists shifted much faster than us toward myopia control, but over time, I watched my colleagues become aware of the problem, recognize that the treatments work and provide them in their offices. The attitude gradually changed from total underestimation of the problem to taking on the responsibility to talk with parents and let them know that myopia control exists,” she said.
Ophthalmologists are now called to go further and step into the education system by making teachers, curriculum developers and legislators aware of the crucial role they are playing in protecting eyesight, particularly under these difficult circumstances.
“School-based vision care programs can make a real difference. Part of our role is to communicate with authorities who can have an impact on educational policies about the importance of maintaining screen time within healthy limits and allowing for outdoor activities,” Smith said.
Ophthalmologists have a double role, according to Wong. First, they need to raise awareness that myopia is a public health problem and a vision-threatening condition.
“Before the pandemic, this was already our responsibility. During the pandemic, because all the attention was focused on the virus, some of these messages may have been diluted. It is quite important that ophthalmologists try to increase the awareness that the prolonged use of digital devices, which was a necessary and beneficial step to cushion the disruption to school education, can have a detrimental impact on the prevalence of myopia,” he said.
Second, ophthalmologists should have an active role addressing their patients, especially those on treatments such as atropine or orthokeratology, to remind them to attend regular follow-up visits.
“We have gone back to almost normal practice, but people are still afraid of going to hospitals. Teleconsultations can help. It is important that these treatments are not stopped to avoid the rebound effect, with the rate of progression going up much faster,” Wong said.
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- Prevalence: Myopia is growing around the world. www.myopiainstitute.org/prevalence.html.
- Reid Chassiakos YL, et al. Pediatrics. 2016;doi:10.1542/peds.2016-2593.
- The new myopia infographic that your patients need to see. mymyopia.com/the-new-myopia-infographic-that-your-patients-need-to-see.
- Wong CW, et al. Am J Ophthalmol. 2020;doi:10.1016/j.ajo.2020.07.034.
- Wu PC, et al. Ophthalmology. 2018;doi:10.1016/j.ophtha.2017.12.011.
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- Zadnik K, et al. JAMA Pediatr. 2019;doi:10.1001/jamapediatrics.2019.0278.
- For more information:
- Jordana M. Smith, MD, can be reached at University of Arizona College of Medicine, 1501 N. Campbell Ave., P.O. Box 245017, Tucson, AZ 85724; email: firstname.lastname@example.org.
- Erin D. Stahl, MD, can be reached at Children’s Mercy Kansas City, 2401 Gillham Road, Kansas City, MO 64108; email: email@example.com.
- Rudolph S. Wagner, MD, can be reached at Doctors Office Center, Suite 6100, P.O. Box 1709, Newark, NJ 07101; email: firstname.lastname@example.org.
- Chee Wai Wong, MD, can be reached at Singapore National Eye Center, 11 Third Hospital Ave, Singapore 168751; email: email@example.com.
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