A systematic review found that children who engaged in remote learning during the COVID-19 pandemic had induced or exacerbated visual disturbances.
The review, conducted in January 2022, found rapid progression of myopia, dry eye and visual fatigue symptoms, and vergence and accommodation disturbances.
The researchers used PubMed, ScienceDirect, and Scopus to search for studies to include. Studies were excluded if they were published before 2020; studied effects of visual health during the COVID-19 lockdown in adults; assessed children with genetic syndromes or visual disabilities; were book chapters, editorials, or opinion pieces; and were published in languages other than Spanish, English, or French.
The 21 studies included in the review were grouped by the main visual outcome of vision status and changes in vision in children. The main effects that were observed were refractive errors (myopia), accommodation disturbances (esotropia), and visual symptoms like dry eye and fatigue. The studies in this review were conducted in Asia (16), Europe (2), and America (3).
There were 11 articles that studied refractive errors in children with virtual learning with myopia progression as the observed visual outcome. There were 8 studies that reported a worsening in the myopia throughout the COVID-19 lockdown in children and teens aged 5 to 18 years. A study also reported a decrease in spherical equivalent refraction (SER) in children with hyperopia and emmetropia.
A study did not find a change in myopia after lockdown in any children and another study found that children all had changes in work time, electronic use time, and outdoor time with myopic children having a significantly lower amount of daily light exposure. The percentage of children with annual progression of myopia increased from 10.5% to 45.9% during the pandemic.
SER was estimated in some studies selected. The mean (SD) SER in children and teenagers with myopia was between –1.94 (2.13) D and –2.7 (1.21) D in 2020, which is significantly lower than in 2019. There was also a decrease in mean SER in children with hyperopia and emmetropia from 0.66 (2.03) D in 2019 to 0.48 (1.81) D in 2020.
A higher incidence of myopia was found in children doing virtual learning. There were also 4 studies that reported accommodation and vergence dysfunction. Lastly, 2 studies that focused on binocular accommodation in a sample of 156 children aged 10 to 17 years found that there was increase in Convergence Insufficiency Symptom Survey scores. Only 1 study did not report a negative effect of the COVID-19 pandemic on visual symptoms in children.
There were some limitations to this study. The inclusion of articles with different study designs made it difficult to compare them in terms of their qualitative and quantitative data. The evidence in the studies was also obtained using different testing methods which may influence the objectiveness of the conclusions. Results may not be generalizable to the rest of the world, as most of the studies took place in Asia.
The researchers concluded that the COVID-19 lockdown and virtual learning had severely affected the vision of children, mostly through more rapid myopia progression, increased frequency of dry eye and visual fatigue, and signs of vergence and accommodation disturbances.
Cortes-Albornoz MC, Ramirez-Guerrero S, Rojas-Carabali W, de-la-Torre A, Talero-Gutierrez C. Effects of remote learning during the COVID-19 lockdown on children’s visual health: a systematic review. BMJ Open. 2022;12:e062388. doi:10.1136/bmjopen-2022-062388