The world is facing a rising epidemic of shortsightedness, with unclear future outcomes. If trends from the past 30 years continue, over 740 million children and adolescents could struggle to see distant objects by 2050, according to new estimates.
These alarming projections stem from a global review that examined the prevalence of myopia, or shortsightedness, using data collected from 50 countries as recently as 2023.
Previous estimates only considered data up to 2015, which already predicted that half the world’s population would be shortsighted by 2050.
The latest analysis, conducted by researchers at Sun Yat-Sen University in China, reviewed 276 studies involving around 5.4 million children and teens, with nearly 2 million cases of myopia.
Public health scientist Jinghong Liang and the team discovered that from 1990 to 2023, the global prevalence of myopia among individuals aged 5 to 19 increased from 24% to 36%.
Japan reported the highest prevalence, with 86% of children and teens experiencing shortsightedness, while Paraguay had the lowest at just 0.84%.
If the current trend continues, the prevalence of myopia among young people worldwide could approach 40% by 2050, translating to more than 740 million cases.
In Asia, this prevalence could reach nearly 70% by 2050.
However, what if the rate accelerates? Data suggests that myopia has been increasing over the past 30 years, particularly since 2020, and this trend is not confined to specific regions.
Previous studies have also linked the COVID-19 pandemic to a decline in eyesight among children.
For example, in 2020, researchers in Hong Kong observed a rapid increase in shortsightedness among 709 children aged 6 to 8.
While genetics certainly plays a role in myopia, it cannot fully account for the recent global surge in cases.
Even when a child has two nearsighted parents, a study indicated that insufficient outdoor time increases the genetic risk of myopia to about 60%.
Outdoor play is believed to lower the risk of myopia in children, yet many kids worldwide were confined indoors during the pandemic. Additionally, school was often conducted virtually, leading to extended screen time for students.
“This is especially important for preschool children, who are in a critical visual development phase characterized by high plasticity,” the authors of the recent global review argue.
They emphasize the need to collect data on variations in myopia prevalence among the youth population over time, noting noticeable differences in ethnicity and geography.
For instance, in Africa, the prevalence of myopia among children and teens is seven times lower than in Asia.
The reasons for this disparity remain unclear, but a correlation exists between educational duration and myopia occurrence. In Singapore and Hong Kong, children as young as two or three actively participate in educational programs before formal schooling begins.
“It is plausible that the earlier introduction of formal educational practices at a young age may influence the incidence of myopia during childhood,” Liang and colleagues suggest.
“These findings are a crucial step towards understanding myopia trends over time, particularly in populations experiencing rapid changes and the significant surge during the COVID-19 pandemic.”
The authors stress the importance of identifying the reasons behind the increasing prevalence of myopia among young people and developing evidence-based strategies to prevent deteriorating eyesight in future generations.
