Abstract
Myopia progression has been found to be worsening during the COVID-19 pandemic. It is important to control the rapid myopia progression in this period. To analyze the association of COVID-19-related lockdown measures with myopia progression in schoolchildren and to compare the performance of defocus incorporated multiple segments (DIMS) lens with that of single vision lens (SVL) treatment in reducing myopia progression. This cohort study involved an exploratory, prespecified, comparison of 2 independent longitudinal studies performed at the same institute beginning in 2019. Data from Hong Kong schoolchildren (aged 7-13 years) were gathered and analyzed. Data analysis was performed from June to July 2021. Schoolchildren in study 1 wore a DIMS lens for 18 months, and those in study 2 wore a SVL for 24 months. Cycloplegic spherical equivalent refraction and axial length were measured. Studies 1 and 2 started before the start of lockdown measures and continued throughout the lockdown. In both studies, periods of fewer and more COVID-19-related lockdown measures were identified. Because COVID-19 lockdown caused deviations from the visit schedule, myopia progression was normalized to 12-month change, which were compared between DIMS and SVL groups, also during the periods with less and more lockdown time. There were 115 participants (58 girls [50.4%]; mean [SD] age, 10.3 [1.5] years) in the DIMS group; their mean (SD) baseline refraction was -4.02 (1.46) D. There were 56 participants (29 girls [51.8%]; mean [SD] age, 10.8 [1.5] years) in the SVL group; their mean (SD) baseline refraction was -2.99 (1.06) D. After controlling for the covariates, DIMS treatment was significantly associated with 34% less axial elongation (0.19 mm [95% CI, 0.16 to 0.22 mm] vs 0.30 mm [95% CI, 0.25 to 0.35 mm]; P < .001) and 46% less myopic progression after 12 months (-0.31 D [95% CI, -0.39 to -0.23 D] vs -0.57 D [95% CI, -0.69 to -0.45 D]; P = .001) compared with SVL treatment. In both the DIMS and SVL groups, more lockdown time was associated with significantly more spherical equivalent refraction (-0.54 D [95% CI, -0.64 to 0.44 D] vs -0.34 D [95% CI, -0.44 to -0.25 D]; P = .01) and axial length (0.29 mm [95% CI, 0.25 to 0.32 mm] vs 0.20 mm [95% CI, 0.16 to 0.24 mm]; P = .001) compared with less lockdown time. No significant interaction between treatment type and lockdown time was observed. In this exploratory analysis, myopia progressed more rapidly in schoolchildren during the period when there were more COVID-19-related lockdown measures. However, optical treatment with DIMS was significantly associated with slower myopia progression compared with SVL treatment during the lockdown period.
Highlights
The COVID-19 pandemic, which is caused by the novel coronavirus SARS-CoV-2, began in December 2019 and has infected more than 100 million individuals and caused millions of deaths globally.[1]
After controlling for the covariates, defocus incorporated multiple segments (DIMS) treatment was significantly associated with 34% less axial elongation (0.19 mm [95% CI, 0.16 to 0.22 mm] vs 0.30 mm [95% CI, 0.25 to 0.35 mm]; P < .001) and 46% less myopic progression after 12 months (−0.31 D [95% CI, −0.39 to −0.23 D] vs −0.57 D [95% CI, −0.69 to −0.45 D]; P = .001) compared with single vision lens (SVL) treatment
In both the DIMS and SVL groups, more lockdown time was associated with significantly more spherical equivalent refraction (−0.54 D [95% CI, −0.64 to 0.44 D] vs −0.34 D [95% CI, −0.44 to −0.25 D]; P = .01) and axial length (0.29 mm [95% CI, 0.25 to 0.32 mm] vs 0.20 mm [95% CI, 0.16 to 0.24 mm]; P = .001) compared with less lockdown time
Summary
The COVID-19 pandemic, which is caused by the novel coronavirus SARS-CoV-2, began in December 2019 and has infected more than 100 million individuals and caused millions of deaths globally.[1]. To restrict and prevent the spread of the pandemic, public health measures, including mandatory mask wearing, social distancing, work-from-home policies, implementation of online school classes, and travel restrictions, have been imposed by governments all over the world. It is reasonable to expect that these measures led to an increase in near work activities for children (digital or otherwise) and substantially less time spent outdoors.[3-5]. Overall, during the periods of lockdown, children spent most of their time at home—that is, their refractive development was overwhelmingly determined by their domestic living environment.[10-12]. In view of these considerations, it is reasonable to expect increased myopia progression in schoolchildren during the pandemic due to the lockdown-imposed behavioral and living style changes.[13]. Recent longitudinal cohort studies[14,15] demonstrated an increased myopia progression in children during the lockdown
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
