It seems intuitive that increased screen time—especially for young patients—can increase myopia development. After all, it increases their near-work and blue light exposure, and, often, decreased sunlight exposure and physical activity. Now, thanks to a Danish study, optometrists have even more research to share with patients.

The Copenhagen Child Cohort 2000 Eye Study is focused on gathering information about our ubiquitous screen devices. These specific findings are in regards to myopia prevalence in 16- and 17-year-old children and its relation to both physical activity and screen time.

Data from 1,443 questionnaires shows that low physical activity and high screen time contribute significantly and can roughly double the risk of developing or worsening myopia. The researchers qualified less than three hours per week of physical activity as “low physical activity” and more than six hours a day “high” screen time. Myopia was defined as non‐cycloplegic subjective spherical equivalent refraction ≤−0.50D.

“Our results support physical activity being a protective factor and near work a risk factor for myopia in adolescents,” the researchers concluded.

Hansen M, Laigaard P, Olsen E, et al. Low physical activity and higher use of screen devices are associated with myopia at the age of 16-17 years in the CCC2000 Eye Study. Acta Ophthalmol. September 9, 2019. [Epub ahead of print].