Outdoor Exposure Beneficial for Vision Maintenance in Children

Time spent outdoors has a negative association with myopia progression in children, according to a study published in the Indian Journal of Ophthalmology.

The study included 495 children 7 to 14 years of age with ≥-0.5 D myopia. Follow up was administered every 6 months for 18 months. Independent variables included age, gender, degree of myopia, and daily outdoor exposure. Researchers defined myopia progression by higher spherical equivalent (SE) values during a period of 18 months.

The researchers found that more time spent outdoors protected against myopia. Intraindividual association between SE and activity scores (in hours) for three subsequent visits was determined by repeated measures correlation. This was calculated as -0.26 (-0.21 to – 0.30; P =.001), revealing a statistically significant negative directional relationship. Ultimately, investigators found that every hour per day spent outdoors negatively impacted SE by 0.06 D on subsequent visits. The findings persisted after controlling for age and baseline activity.

“The protective effect of daylight outdoor activities suggests that a public health measure aimed at preventing the progression of myopia could be based on increasing hours of outdoor activity for children, targeting not only the parents but also the schools to bring about changes in the school curriculum to increase the outdoor activity,” according to the investigators. “This may prove to be a simple strategy to reduce the progression of myopia and may also help in the general health of the children.”

Study limitations include a single center design and dependence on parental reporting for data.

Reference

Gupta S, Joshi A, Saxena H, Chatterjee A. Outdoor activity and myopia progression in children: A follow-up study using mixed-effects model. Indian J Ophthalmol. 2021;69(12):3446-3450. doi:10.4103/ijo.ijo_3602_20