Increased screen time during pandemic linked to rise in short-sightedness among children, study suggests

Lifestyle changes driven by the coronavirus pandemic have been linked to a possible rise in short-sightedness among children in a new study.

Analysing children in Hong Kong between the ages of six and eight, researchers found a potential increase in cases of myopia after the pandemic struck.

They also found a sharp rise in the amount of screen time and a significant drop in time spent playing outdoors.

Two separate groups of children were included in the analysis, published in the British Journal Of Ophthalmology. One group was recruited at the start of the pandemic, and the other was already participating in a separate study before the arrival of Covid-19.

Studying the eyesight and behaviour of 1,793 children during the pandemic, the researchers found that, after a period of follow-up, some 19 per cent of the children observed during the health crisis were myopic.

This compared with just 13 per cent in the group observed before the pandemic hit.

“Another alarming finding from our report is the significant changes in children’s lifestyle during the Covid-19 pandemic, with 68 per cent decreased outdoor time and 2.8-fold increased screen time,” the authors wrote.

“Evidence suggests that when children are out of school, they are physically less active and have much longer screen time, and of all the environmental risk factors that have been studied, increased outdoor time has been consistently shown to have a protective role against the development of myopia.”

The authors, from The Chinese University of Hong Kong, concluded: “We showed a potential increase in myopia incidence among schoolchildren in Hong Kong during the Covid-19 pandemic.

“There was also a significant decrease in outdoor time and increase in near work time in 6-8-year-old school children.

“Our results serve to warn eye care professionals, and also policy makers, educators and parents, that collective efforts are needed to prevent childhood myopia, a potential public health crisis as a result of Covid-19.”

However, Oliver Braddick, an emeritus professor of psychology at the University of Oxford, poured some cold water on the findings, suggesting the researchers had not been able to make “the most direct comparison” between the two groups.

“The Covid pandemic provided an interesting opportunity to examine whether the imposed changes in lifestyle changed the development of eyesight in primary-age children,” Professor Braddick said.

“It’s unfortunate, however that this study could not make the most direct comparison between development of myopia in the pre-Covid and Covid-period cohorts, since the two groups were followed up over different intervals of time.

“However, there is other evidence from a study in Sydney in 2013 that outdoor activity in daylight has a protective effect against children developing short-sightedness, which is consistent with the findings of this study.

“It should be noted that this study was carried out in an urbanised East Asian population, among whom myopia levels are generally higher than in groups of European ancestry.”

In 2018, a study by eye doctors at King’s College London also linked children’s use of smartphones and other devices – alongside being born in the summer months – to a growing epidemic of short-sightedness.

Meanwhile, researchers at the University of New South Wales predicted in 2016 that incidences of myopia will increase sevenfold over the next three decades, with around 4.8 billion people expected to be short-sighted by the year 2050.

Additional reporting by PA