Sight Lines

Author: Elinor Nauen
Source: Healthy Living, July-September 2007

Protecting Yourself From Clouded Vision And Potential Blindness

Imagine all you would miss if you lost your sight: loved ones’ faces, spring flowers, favorite tv shows. In the U.S., 1 million blind adults ages 40 and older, and 2.4 million adults who are visually impaired, do without life’s images. By 2020, there could be 5.5 million such cases, according to the National Eye Institute (NEI). Here’s a rundown of the leading causes of blindness and vision impairment.

Cataracts occur when the clear lens of the eye clouds over. Age is the main risk factor, along with smoking, diabetes and overexposure to sunlight. In this country, cataracts affect 20.5 million people older than 40; by 80, more than half of Americans develop the condition. Younger adults or children can also develop cataracts-usually from eye injury or steriod use, but sometimes diabetes is the cause.

Age-related macular degeneration (AMD) is a leading cause of vision loss for people 60 and older; it affects more than 1.6 million Americans. “With AMD, people can no longer read, drive, play cards, recognize their friends in a room full of people or see their grandkids,” says J. Timothy Stout, M.D., Ph.D., associate profesor of ophthalmology at Casey Eye Institute in Portland, OR. See a doctor if straight lines appear wavy, printed type blurs or your central vision darkens.

You may be able to take protective measures against AMD. “People who eat more fish and dark-green leafy vegetables, which contain the vitamins lutein and zeaxanthin, appear to have a lower risk of severe AMD,” says Emily Chew, M.D., the NEI’s deputy director of epidemiology and clinical research.
 
An NEI-sponsered study is testing whether omega-3 fatty acids, lutein and zeaxanthin supplements will delay or prevent the deterioration of AMD. Previous research found that high doses of zinc, beta-carotene and vitamins C and E reduce risks. And don’t smoke; at a minimum, doing so doubles your risk, says Dr. Chew.

With glaucoma, fluid builds up in the eye and presses on the optic nerve, gradually damaging it. Unfortunately, vision loss-which is irreversible-occurs without symptoms and only after a significant amount of nerve damage. This means that as many as half of the more than 4 million people in this country who have glaucoma don’t even realize they have it. Risk factors include diabetes, a family history of glaucoma, and being African-American.

Diabetic Dangers

Diabetic retinopathy, a common complication of diabetes, afflicts more than 5.3 million Americans. The condition occurs when abnormal blood vessels develop in the retina, eventually they cause bleeding, scar, formation and, finally, severe vision loss. “It’s insidious and can come on without warning,” says Dr. Chew of the NEI. Nearly half of those with diabetes develop some degree of diabetic retinopathy. “But if you tightly control blood sugar, you can reduce your risk or the progression of this eye disease by as much as 70 percent,” Dr. Chew notes. Laser surgery and vitrectomy, which clears blood and debris from the eye, can help. If you have diabetes, get an eye exam every year.