New analysis has predicted the global prevalence of myopia in children and teens will top 740 million cases by 2050.
Being female, from East Asia or urban residential areas, and educational level all seem to be key factors in influencing prevalence, according to the pooled data analysis published in British Journal of Ophthalmology.1
Myopia has emerged as a major public health concern, with many describing it as a pandemic. But the most recent global review only went up to 2015.
To obtain a more up-to-date picture, the researchers estimated the current and future prevalence of myopia up to 2050 among five to 19-year-olds.
The analysis included a total of 276 studies, involving almost 5.5 million children and teens and almost two million cases of myopia, from 50 countries in Asia, Europe, Africa, Oceania, and North and Latin America.
The analysis revealed a more than tripling in overall prevalence between 1990 and 2023, rising from 24% in 1990–2000 to 25% in 2001–10. This was followed by much sharper increases to 30% in 2011–19, and 36% in 2020–23 – equivalent to around one in every three children and teens.
While the prevalence among teens surpassed that of children, peaking at 54% during 2020–23, the absolute increase among children from 1990 to 2023 was nearly twice that of teens.
Prevalence was significantly higher in low to middle income countries than in high income countries. Higher prevalence was also associated with living in East Asia (35%) or in urban areas (29%), female sex (34%), adolescence (47%), and secondary school education (46%).
The researchers projected that based on the figures and trends up to 2023, global myopia prevalence in this cohort would reach around 40% by 2050, exceeding 740 million cases, up from 600 million in 2030, they estimate.
The analysis revealed a more than tripling in overall prevalence between 1990 and 2023…
Alarming East Asian Statistics
The researchers noted that the “prevalence of uncontrolled myopia in East Asia, especially in China, is alarmingly high compared with the rest of the world”.
The study also suggested that the COVID-19 pandemic may have had a role in the sharp increase after 2020.
Notably, during the COVID-19 pandemic, many countries implemented nationwide lockdowns as an emergency domestic quarantine measure to control the transmission of the virus. The Chinese government also initiated a nationwide school closure, which resulted in over 200 million students having to complete their studies online from their homes.
“However, recent concerns have been raised about the potential negative impact of prolonged lockdowns on eye health, specifically myopia. This is due to the decrease in outdoor activities and increase in screen time that may result from extended periods of staying indoors.”
By way of an explanation for the geographical differences, the study authors suggest that people in East and South Asia have experienced rapid economic development along with the steepest rise in myopia prevalence.
“The elevated incidence of myopia observed in the Asian population, particularly among younger children, as compared with other regions, could potentially account for the observed ethnic disparity,” they write.
“Moreover, a correlation between the duration of education and the occurrence of myopia has been observed, suggesting that the early implementation of formal education in certain East Asian nations could potentially serve as a contributing element.
“Conversely, African populations exhibit a lower prevalence of myopia, likely attributed to lower literacy rates and delayed initiation of formal education,” they explained.
They suggested sex differences in prevalence might also be explained by the fact that girls reach puberty faster than boys and tend to spend less time outdoors and more time on close-range activities.
Close to Precise
The researchers acknowledge various limitations to their findings, including the variable quality and considerable differences in the design and methodology of the studies included in their pooled data analysis. The definitions and assessments of myopia also varied widely.
“Despite these known limitations, given the large sample size included, our estimates of the prevalence of myopia are considered to be close to the precise number,” they wrote.
Reference
- Liang J, Pu Y, Chen J, et al. Global prevalence, trend and projection of myopia in children and adolescents from 1990 to 2050: A comprehensive systematic review and meta-analysis, British Journal of Ophthalmology. Published Online First: 24 September 2024. doi: 10.1136/bjo-2024-325427.
