Association of myopia with screen time use in pediatric patients in a tertiary hospital in Saudi Arabia

Introduction and Literature review

Myopia, commonly known as nearsightedness, is a major cause of visual disability.¹ The prevalence of myopia is increasing worldwide, especially in urbanized countries, where children are less likely to spend time outdoors.² By 2050, it is predicted that myopia would affect half of the population.³ The estimated prevalence of refractive error in Saudi children was around 17.5%, out of which myopia prevalence was 40.8%.⁴ In addition to the disease burden of myopia it also hinders academic performance of children, in two large scale studies in China,^5,6 it was concluded that the correction of myopia was linked with significant improvements in the academic performance of children.

Myopia is caused by an increase in axial length of the eyeball, resulting in refractive error. In normal eyes, the image of distant objects is focused on photoreceptors in the retina, and the image of near objects is focused behind the photoreceptors, but it is corrected by the lens accommodation. While in myopic eyes the image of a distant object is focused in front of the photoreceptors and cannot be corrected even with the accommodation of the lens.¹

Myopia in childhood is the result of complex processes, one of them is emmetropisation, where refractive components of the eye balance each other to reach normal vision. As children are born hyperopic, correction occurs with growth when the eyeball elongates until it reaches normal vision.⁷ Myopia develops when the elongation continues instead of stabilizing. The lens power also changes in childhood, to prevent the possible myopic shift caused by emmetropisation, but the decrease in lens power can continue, therefore causing myopia.⁷

Several genetic and environmental risk factors have been strongly associated with the development of myopia, including outdoor activities, near work and family history.⁸ Numerous studies have reported that children who spend more time outdoors and read at a proper distance of more than thirty centimeters for a period of less than thirty minutes, have a lower risk of developing myopia in comparison to those who do not.^9,10 Moreover, children of myopic parents are at a greater risk of being myopic as a study by Pan et al. 2012, has shown that the risk of myopia development increases two times if a child has one myopic parent.⁸

The rise in digital use and concurrent eye complaints, such as eye strain and dry eye syndrome, have provoked investigations for the underlying pathogenesis and possible correlation.¹¹ Although there is insufficient evidence on the correlation of artificial light exposure with different eye conditions, several studies conducted on animals have explored the impact of light on the eyes.^12–14 The studies have concluded that light can damage the retina via three different mechanisms, photochemical, photo-thermal and photomechanical. Photochemical damage is associated with an oxidative process that results from exposure to light while photomechanical damage is dependent on the amount of energy. Photo-thermal damage occurs with high intensity light that raises the temperature of the tissues, subsequently causing damage. In addition, exposure to light is not only associated with physiological changes in the ocular surfaces but also found to have an effect on the circadian rhythm.¹⁵

A systematic review and meta-analysis study by Foreman et al. 2021, was done to review the literature on the relationship between digital screen time and myopia through the appraisal of thirty-three existent literature. The study results concluded that smartphones alone, or with computer screen time, can be linked to a greater risk of developing myopia.¹⁶ Moreover, another study was conducted in Spain by Alvarez et al. to assess the connection between screen and outdoor time and myopia rates among children. A thorough examination of the vision of 7,497 children between the ages of five and seven was done during the “Annual School Campaign for Children’s Visual Health” which was associated with children’s lifestyle, considering hours per day spent on digital devices and daily outdoor time. The results concluded that children with myopia reported more screen time and less outdoor time.¹⁷

In another meta-analysis study from 2020, which included 14 studies, the total of participants was 27,110 ranging in age from 9.5 to 26.0 years. The aim was to evaluate whether using smartphones excessively causes visual impairments, the cross-sectional studies yielded a pooled odds ratio (OR) of 1.05, which indicates that excessive smartphone use is not extensively linked to myopia or blurred vision, but these ophthalmologic problems were more evident in children (OR 1.06) than in young adults (OR 0.91).¹⁸ In addition, a different meta-analysis study from the same year was done to determine the association between screen time and the risk of developing myopia in children. The results were mixed, but notably the more recent included studies showed an association trend.¹⁹

There are two recent Saudi studies published in 2023, one done in the city of Bisha reported the prevalence of myopia to be around 32.7% among schoolchildren,²⁰ while another one done in Jeddah found it to be 40.7% in children below the age of 14 years old.²¹ In that study, the use of electronic devices was not a statistically significant risk factor, while the presence of family history in a first degree relative was associated with increased risk of myopia.

Studies on myopia risk factors have been conducted, however in the last decade, myopia cases have increased steadily, along with the widespread use of electronic devices which led us to investigate if there is a link between them. The lack of solid and conclusive data regarding the correlation between children’s continuous usage of digital devices and the development of myopia in Saudi Arabia led us to build this project. The purpose of our study is to study the connection between the prolonged use of screen time and development of myopia in children between the ages of 4 and 12 in Saudi Arabia.

Methods

Results

The study included complete records of 94 myopic patients and 146 controls, shown in Table 1, aged 4 to 12 years, of both genders. In the myopic group, the mean age was 8.21 ± 2.37 years, with a notable proportion (38 patients, 40.4%) aged 7–9 years. The majority of patients were female (55, 58.5%), and more than half were Saudi nationals (68, 72.3%). A significant proportion had a family history of myopia (81, 86.2%), and nearly half (45, 47.9%) spent more than one hour outdoors each day.

In the control group, the mean age was 8.38 ± 2.83 years, with a substantial proportion (61 controls, 41.8%) aged 10–12 years. Most controls were male (78, 53.4%), and the vast majority were Saudi nationals (143, 97.9%). A considerable proportion had a family history of myopia (92, 63.0%), and more than half (79, 54.1%) spent over one hour outdoors each day.

Figure 1 illustrates the distribution of myopia categories among the patients. The results showed that the majority of patients had mild myopia (54 patients, 57.5%), followed by moderate myopia (33 patients, 35.1%), and the least number had high myopia (7 patients, 7.4%)

Figure 1. The number of screen media devices present in the household where the child lived among the Myopic and Control groups.

Figure 2 shows the age distribution of patients at the time of their first myopia diagnosis. The results revealed that most of the patients were first diagnosed with myopia aged 4–6 years (38 patients, 40.4%), followed by those aged 7–9 years (26 patients, 27.7%), 10–12 years (17 patients, 18.1%), and the smallest group was those aged under 4 years (13 patients, 13.8%).

Figure 2. Child age when first diagnosed with myopia.

The most commonly used screen media devices among myopic children were smartphones (98.9%) and laptops (87.2%), while in the control group, the most commonly used devices were television (95.9%) and smartphones (94.5%). The results revealed a statistically significant association between the ownership of screen media devices, bringing devices to school, and myopia, with p-values of <0.001. A considerable proportion of children in the myopic group owned a smartphone (54, 57.4%), a laptop (22, 23.4%) and an e-reader (9, 9.6%), compared to the control group. Additionally, more proportion of children in the myopic group brought a tablet/iPad to school on a daily or weekly basis (5.3%) than in the control group (3.4%). Other attributes were not statistically significant across the true groups.

Figure 3 shows the types and numbers of screen media devices present in the households where the children lived. It reveals that a higher proportion of smartphones and laptops were found in the myopic group than in the control group

Figure 3. The number of screen media devices present in the household where the child lived among the Myopic and Control groups.

Figure 4 shows the frequency of screen media device usage by children in households over the past month. The results indicate a higher frequency of device use among children in the control group compared to those in the myopic group, with television and smartphones being the most commonly used devices.

Figure 4. The frequency of use of screen media devices by the child in the household in the past month with respect to the Myopic and Control groups.

Figure 5 shows children’s ownership of screen media devices. The findings revealed that most smartphones, laptops, and e-readers were owned by children in the myopic group (p<0.001), while most televisions, tablets/iPads and both handheld and non-handheld gaming consoles were owned by children in the control group.

Figure 5. Children’s ownership of screen media devices among the myopic and control group.

Table 3 shows the distribution of time spent on screen-based activities per day by children in the myopic and control groups over the past month. The study found no significant difference in the amount of time spent on screen-based activities during weekdays and weekends between the myopic and control groups

Table 4 presents the distribution of screen-based activity use in the myopic and control groups. The results showed that more than half of the children in both groups used screen media within half an hour after waking up in the morning for 0–2 days per week: 54 children (57.5%) in the myopic group and 96 children (65.8%) in the control group (p = 0.004). Additionally, a notable proportion of children in both groups used screen media within half an hour before going to sleep for 0–2 days per week: 35 children (37.2%) in the myopic group and 82 children (57.5%) in the control group (p = 0.043). The study also found that a significant proportion of children in both groups (myopic: 17 children, 34.0%; control: 30 children, 36.6%) were aged 7–9 years when they first got their own tablet (p = 0.012).

Table 5 (below) presents the attributes of patients by myopia category. The results indicate a significant association between patients’ age, their age at which they were first diagnosed with myopia and their myopia category (p = 0.030 and p = 0.005, respectively). However, no other patient attributes were significantly associated with myopia category.

Table 6 presents the Analysis of Variance (ANOVA) results of total screen time in children, based on their age at first use of screen media devices (smartphone, tablet, and laptop). The results indicate that the differences between these groups were not statistically significant (p = 0.196). This suggests that the age at which children first used screen media devices does not explain the variation in their total screen time.

Table 7 presents the results of a one-way ANOVA examining the mean difference in total screen time between groups categorized by the age of the children (4–6 years, 7–9 years, and 10–12 years). The results revealed a statistically significant difference across the groups (p= 0.021). This suggests that total screen time differs substantially across the age groups children.

Discussion

The increasing use of screen media devices among children has raised concerns about its potential link to the growing prevalence of myopia.²⁹ While factors such as physical activity, genetics, screen time, and time outdoors contribute to myopia, the relationship between screen time and myopia is not fully understood.³⁰ This study aimed to explore the association between screen time and myopia in pediatric patients at King Fahad University Hospital, providing insights into the impact of screen use on children’s eye health.

The study revealed considerable exposure of children to screen media, including smartphones, laptops, and tablets. It found a higher proportion of smartphones (98.9%) and laptops (87.2%) in households with children in the myopic group, compared to the control group, which had lower proportions of smartphones (94.5%) and laptops (87.0%). These findings are consistent with those of Rideout and Robb, who observed a significant increase in average daily screen time up to 5 hours and 7 minutes in children, aged 8 to 12 in 2019. This poses a high risk of myopia and could also affect academic performance with television and smartphones being the most commonly used devices in both groups³¹ ( Table 2).

The study found that a substantial proportion of children, particularly in the myopic group, owned smartphones (57.4%) and laptops (23.4%), compared to the control group, where the proportions were lower: smartphones (42.5%) and laptops (15.1%). This highlights the increasing screen time over the years, an observation that aligns with a 2018 report which found that about 5% of children aged 5 to 7 globally already owned a mobile phone, and 42% had their own tablet; an observation which can be linked to the rising number of myopic children globally.³²

The study reported a higher frequency of screen media use among the myopic group compared to the control group. Children in the myopic group used tablets, smartphones, and computers more frequently for school-related activities (92.6%) and more children in the myopic group (5.3%) regularly brought a tablet/iPad to school compared to the control group (3.4%), highlighting the increasing prevalence of myopia associated with higher screen time ( Table 2).

The results showed that more than half of the children in both groups used screen media within half an hour after waking up in the morning for 0–2 days per week: 54 children (57.5%) in the myopic group and 96 children (65.8%) in the control group (p = 0.004). Similarly, a notable proportion of children in both groups used screen media within half an hour before going to sleep for 0–2 days per week: 35 children (37.2%) in the myopic group and 82 children (57.5%) in the control group (p = 0.043). The study also found that early and frequent exposure to screen media was associated with a higher risk of myopia in children. A significant proportion of both groups (myopic: 17 children, 34.0%) received their first tablet at ages 7–9 years (p = 0.012). These findings highlight the importance of regulating children’s screen media use to reduce the risk of myopia ( Table 4).

The study found a significant association between patients’ age, the age at which they were first diagnosed with myopia, and their myopia category (p = 0.030 and p = 0.005, respectively). Children aged 4-6 years were more likely to have high myopia, consistent with findings by Smith and Walline who observed a high prevalence of myopia among children aged 4 to 7 years.³³ This association may be attributed to increased indoor activities and reduced time spent outdoors in this age group, which increases their risk of myopia due to prolonged exposure to screen media devices³⁴ ( Table 5).

The current study also found that a younger age at diagnosis was associated with a higher likelihood of developing high myopia, with children under 4 years old being more likely to develop high myopia. This is consistent with Rose et al.’s observation that the association is due to the longer duration of myopia progression. Early onset of myopia gives the eye more time to grow and elongate, increasing the potential for worsening myopia and raising the likelihood of high myopia.⁹ The analysis of variance results indicates that differences in screen time based on children’s age at first use of screen media devices (smartphone, tablet, and laptop) were not statistically significant (p = 0.196). This suggests that the age at which children first use screen media devices does not account for the variation in their total screen time ( Table 6).

The result revealed statistically significant difference in total screen time between age groups (4–6 years, 7–9 years, and 10–12 years), with a (p-value=0.021) suggesting that total screen time increases with age ( Table 7). This finding is consistent with a study conducted in Spain by Alvarez-Peregrina et al., which found that the number of hours spent using electronic devices increased significantly with age, with children aged 7 years and older spending more time on these devices.¹⁷ The increasing frequency of screen media use among children, both at home and school, highlights the growing dependence on technology in their daily activities.

There are a few limitations to this study, which needs to be considered. This research was confined in the data collection aspect as the research population was limited to pediatric ophthalmology patients of KFHU only, while it could cover wider population of patients from other hospitals for a stronger association. Further research in a larger population is needed to support the findings of this study. The lack of detailed and accurate information on the timing and severity of myopia poses significant constraints on achieving the study’s objectives.

Conclusion

The study established a significant association between patients’ age, the age at first diagnosis and myopia levels in pediatric patients attending King Fahad University Hospital (KFUH) in Saudi Arabia from November 2021 to November 2023. The patients’ screen time varied substantially across the age groups (4–6 years, 7–9 years, and 10–12 years); with smartphones being the most commonly used devices among both myopic children and control group. These findings highlight the need to better understand the relationship between myopia and screen time in pediatric patients, in order to develop evidence-based guidelines for managing screen time, protecting children from the adverse effects of screen media exposure, and promoting their eye health and overall well-being. This study can guide future research on the subject of screen time and children’s development and health, specifically for myopia and its prevention, this study also contributes to the literature and research at the local level in the Eastern Province of Saudi Arabia.

Ethics and consent

Ethical approval was obtained from the Institutional Review Board (IRB) at Imam Abdulrahman bin Faisal University. The approval was granted on November 12, 2023, under the number IRB-UGS-2023-01-486.

Written informed consent was obtained from all guardians after they were fully briefed on the study’s goals. They were also assured of the confidentiality and privacy of their personal information. Additionally, participants were informed that their participation was voluntary and that they could withdraw at any time without consequence.