The clinical

trial called the Age-Related Eye Disease Study (AREDS) was sponsored by

the National Eye Institute (NEI), one of the Federal government's National

Institutes of Health.

"This

is an exciting discovery because, for people at high risk for developing

advanced AMD, these nutrients are the first effective treatment to slow

the progression of the disease," said Paul A. Sieving, M.D., Ph.D.,

director of the NEI. "AMD is a leading cause of visual impairment

and blindness in Americans 65 years of age and older. Currently, treatment

for advanced AMD is quite limited. These nutrients will delay the progression

to advanced AMD in people who are at high risk those with intermediate

AMD in one or both eyes, or those with advanced AMD in one eye already.

"The nutrients

are not a cure for AMD,

nor will they

restore vision already lost from the disease," Dr. Sieving said.

"But they will play a key role in helping people at high risk for

developing advanced AMD keep their vision."

A common feature

of AMD is the presence of drusen, yellow deposits under the retina. Often

found in people over age 60, drusen can be seen by an eye care professional

during an eye exam in which the pupils are dilated. Drusen by themselves

do not usually cause vision loss, but an increase in their size or number

increases a person's risk of developing advanced AMD, which can cause

serious vision loss.

Scientists

are unsure about how or why an increase in the size or number of drusen

can sometimes lead to advanced AMD, which affects the sharp, central vision

required for the "straight ahead" activities, such as reading,

driving and recognizing faces of friends.

"Previous

studies have suggested that people who have diets rich in green, leafy

vegetables have a lower risk of developing AMD," said Frederick Ferris,

M.D., director of clinical research at the NEI and chairman of the AREDS.

"However, the high levels of nutrients that were evaluated in the

AREDS are very difficult to achieve from diet alone.

"Almost

two-thirds of AREDS participants chose to take a daily multivitamin in

addition to their assigned study treatment," Dr. Ferris said. "The

study also showed that, even with a daily multivitamin, people at high

risk for developing advanced AMD can lower the risk of vision loss by

adding a formulation with the same high levels of antioxidants and zinc

used in the study."

Dr. Ferris

said some people with intermediate AMD may not wish to take large doses

of antioxidant vitamins or zinc medical reasons.

"For example,

beta-carotene has been shown to increase the risk of lung cancer among

smokers," he said. "These people may want to discuss with their

primary care doctor the best combination of nutrients for them. With the

use of the high levels of zinc, it is important to add appropriate amounts

of copper to the diet to prevent copper deficiency."

The AREDS participants

reported few side effects from the treatments. About 7.5 percent of participants

assigned to the zinc treatments compared with five percent who did not

have zinc in their assigned treatment had urinary tract problems that

required hospitalization.

Participants

in the two groups that took zinc also reported anemia at a slightly higher

rate; however, testing of all patients for this disorder showed no difference

among treatment groups. Yellowing of the skin, a well-known side effect

of large doses of beta-carotene, was reported slightly more often by participants

taking antioxidants.

"The AREDS

formula is the first demonstrated treatment for people at high risk for

developing advanced AMD," Feris said. "Slowing the progression

of AMD to its advanced stage will save the vision of many who would otherwise

have had serious vision impairment."

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