Seeing Clearly: Kids and the Great Outdoors

Myopia may decrease when children spend more time outside

(RxWiki News) Nearsightedness in children is a major problem in some areas of the world. But there may be a simple solution.

A new study from China found that myopia (nearsightedness) decreased when children spent more time outdoors. This study offers the first indication that myopia may be preventable.

"Among 6-year-old children in Guangzhou, China, the addition of 40 minutes of outdoor activity at school compared with usual activity resulted in a reduced incidence rate of myopia over the next three years," wrote lead study author Mingguang He, MD, PhD, a professor of ophthalmology at Sun Yat-sen University in China, and colleagues.

According to Dr. He and team, myopia has become a problem of epidemic proportions for young adults in urban areas of East and Southeast Asia. In some cities, between 80 and 90 percent of high school graduates have myopia.

"Vision scientists have long suspected that prolonged near visual effort was a risk factor for the development of myopia," said Christopher J. Quinn, OD, FAAO, president at Omni Eye Services in Iselin, NJ, and a member of the medical staff at Robert Wood Johnson University Hospital, in an interview with dailyRx News. "This study suggests that increased outdoor activity, which presumably means less time performing near point tasks, is mildly protective for the development of myopia."

Dr. Quinn added, "Although myopia in the US is less common than in Asia, it is estimated to affect at least 30 percent of school-aged children in the US. Further study to determine the exact mechanism by which increased outdoor activities reduce the development of myopia will be helpful in guiding public health strategies to reduce the development of myopia."

Myopia has also been gradually increasing in European and Middle Eastern populations.

For this study, Dr. He and team looked at more than 1,800 first graders from 12 schools in Guangzhou, China.

These children were split into two groups. The first group spent an extra 40 minutes of class time outside. Parents were also asked to encourage their children to spend more time outdoors. The second group continued usual activities.

The children were followed for three years.

About 30 percent of children in the outdoor group developed myopia. In the control group, that figure was around 40 percent.

According to Dr. He and team, when young children develop myopia, the condition is likely to progress. Anything that could delay the onset or progression of myopia would likely have benefits over the long-term.

In an editorial about this study, Michael X. Repka, MD, of Johns Hopkins University School of Medicine in Baltimore, wrote, "Given the popular appeal of increased outdoor activities to improve the health of school-aged children in general, the potential benefit of slowing myopia development and progression by those same activities is difficult to ignore. Although prescribing this approach with the intent of helping to prevent myopia would appear to have no risk, parents should understand that the magnitude of the effect is likely to be small and the durability is uncertain.”

This study was published Sept. 15 in the journal JAMA.

The State Key Laboratory in Ophthalmology and the National Natural Science Foundation of China funded this research. No conflicts of interest were disclosed.


Review Date: 
September 10, 2015