August 2, 2021

expert reaction to observational study looking at lifestyle changes and levels of short-sightedness in school children during the pandemic

An observational study published in British Journal of Ophthalmology looks at myopia (short-sightedness) incidence and lifestyle changes among  school children during the COVID-19 pandemic.

Prof Oliver Braddick FMedSci, Emeritus Professor of Psychology, University of Oxford, said:

“The COVID pandemic provided an interesting opportunity to examine whether the imposed changes in lifestyle changed the development of eyesight in primary-age children.  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 (e.g. from a study in Sydney in 2013) that outdoor activity in daylight has a protective effect against children developing myopia (short-sightedness), which is consistent with the findings of this study.

“It should be noted that this study was carried out in an urbanized East Asian population, among whom myopia levels are generally higher than in groups of European ancestry.  It remains unclear whether there is any genetic component to this difference, or whether it is a result of cultural factors – the Sydney study found that children of Asian ancestry spent more time in near-work, and less outdoors, than their European-ancestry peers – both factors linked to myopia development.  Thus it is hard to know how far the findings from Hong Kong would be mirrored in a European population.  However, the European children in Sydney showed the same effects of near work and time outdoors.”

References:

Morgan IG, French AN, Ashby RS, Guo X, Ding X, He M, Rose KA. The epidemics of myopia: Aetiology and prevention. Prog Retin Eye Res. 2018 Jan;62:134-149. doi: 10.1016/j.preteyeres.2017.09.004. Epub 2017 Sep 23. PMID: 28951126.

https://pubmed.ncbi.nlm.nih.gov/28951126/

French AN, Morgan IG, Mitchell P, Rose KA. Risk factors for incident myopia in Australian schoolchildren: the Sydney adolescent vascular and eye study. Ophthalmology. 2013 Oct;120(10):2100-8. doi: 10.1016/j.ophtha.2013.02.035. Epub 2013 May 11. PMID: 23672971.

https://pubmed.ncbi.nlm.nih.gov/23672971/

French AN, Morgan IG, Mitchell P, Rose KA. Patterns of myopigenic activities with age, gender and ethnicity in Sydney schoolchildren. Ophthalmic Physiol Opt. 2013 May;33(3):318-28. doi: 10.1111/opo.12045. Epub 2013 Mar 4. PMID: 23452023.

https://pubmed.ncbi.nlm.nih.gov/23452023/

‘Myopia incidence and lifestyle changes among  school children during the COVID-19 pandemic: a population-based prospective study’ by Xiujuan Zhang et al. was published in British Journal of Ophthalmology at 23:30 UK time on Monday 2 August.

DOI: 10.1136/bjophthalmol-2021-319307 

Declared interests

Prof Oliver Braddick: No conflict of interest