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TUESDAY, Aug. 3, 2021 (HealthDay News) -- The incidence of myopia increased among schoolchildren in Hong Kong during the COVID-19 pandemic, according to a study published online Aug. 2 in the British Journal of Ophthalmology.
Xiujuan Zhang, Ph.D., from The Chinese University of Hong Kong, and colleagues examined myopia incidence, spherical equivalent refraction (SER), and lifestyle changes among schoolchildren aged 6 to 8 years in Hong Kong during the COVID-19 pandemic. Two separate longitudinal cohorts were included: the COVID-19 cohort, recruited at the beginning of the COVID-19 pandemic (709 children with 7.89 ± 2.30 months of follow-up), and the pre-COVID-19 cohort, recruited before the pandemic (1,084 children with 37.54 ± 3.12 months of follow-up).
The researchers found that the overall incidence of myopia was 19.44 and 36.57 percent in the COVID-19 and pre-COVID-19 cohorts, respectively. The change in SER was −0.50 ± 0.51 D and change in axial length was 0.29 ± 0.35 mm. There was a decrease in time spent on outdoor activities (from 1.27 ± 1.12 to 0.41 ± 0.90 hours/day), while an increase in screen time was observed (from 2.45 ± 2.32 to 6.89 ± 4.42 hours/day).
"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," the authors write.