Nearsightedness (myopia) becoming more frequent, affects 42% of Americans

From Reuters:

Data from the National Health and Nutrition Examination Survey (NHANES) was used to compare the percentage of Americans aged 12 to 54 with myopia in 1971-1972 and 1999-2004:

- In 1971 to 1972, 25 percent of Americans aged 12 to 54 had myopia.

- This figure had jumped to 42 percent in the 1999-2004 period.

The prevalence of myopia was roughly 66 percent higher in the 1999-2004 period than in the 1971-1972 period.

Reports from Asia, Australia, Africa, and Israel have shown that the prevalence of myopia is increasing in there as well.

Researchers don't know why more Americans are becoming nearsighted.

There have been studies linking myopia to "more close-up work" such as:

- reading
- sitting at a computer screen
- using small electronic devices

An Australian study suggested that children who spent the most time outdoors were the least likely to suffer from myopia. Outdoors you are looking at distant objects instead of near objects. Children who spent 14 hours outdoors per week was the lowest risk group. A study showed nearly 90 percent rates of myopia in medical students in Singapore.


Medical Detectives Focus On Myopia. NPR.

References:

Trouble seeing? You're not alone. Reuters.
Archives of Ophthalmology, December 2009.
20-20-20 rule: For every 20 minutes of reading a screen take a 20-second eye break, look at something beyond 20 feet. NYTimes, 2012.
Medical Detectives Focus On Myopia. NPR.
Live Web Chat: Vision Problems And Laser Surgery. NPR.

Scientists identified a gene that causes short-sightedness - RASGRF1 http://goo.gl/cATk

Impact of Pediatric Vision Disorders in Adulthood - impacts health, self-perception, educational attainment, job choices http://goo.gl/y1EHg

Self adjustable spectacles. Which idea is likely to make the biggest impact on healthcare by 2020? BMJ http://goo.gl/sKnrS
People with low vision can drive with 'bioptics' -  small telescopes mounted on eyeglass frames  http://goo.gl/sUIQh and http://j.mp/qEJZv7
Image source: OpenClipArt.org.