Age-Related Macular Degeneration (AMD)
What is AMD?
AMD develops when the metabolism of the cells in
the macula (the "central, sharp vision" part of your retina)
deteriorate or break down. The result is a loss of the vision in your
central field of view, comparable to constantly looking into a dark
tunnel.
Unfortunately, there is no effective
treatment or cure so it is extremely important to thoroughly educate yourself about how to decrease your risk of developing AMD.
Statistics
AMD remains the number one cause of severe, uncorrectable vision loss in the
aging population. It affects more than 11 million Americans, with a
prevalence of up to 9.2% of those over 40. AMD accounts for more than 14%
of new cases of legal blindness every year in the U.S. The "dry"
or "atrophic" form of AMD accounts for about 90% of these cases, while
the wet form is associated with 80% of the cases which result in
blindness. Approximately 12-21% of patients with dry AMD progress to
vision loss of 20/200 or worse.
Take the following "Eye-Q" test to see how much you know about the causes, risk factors, and preventative measures of AMD.
True or False?
1. You don't really need to worry about
AMD until age 60.
FALSE. If you wait until age
60, it may be too late. Although AMD is diagnosed most often in people
over the age of 60, macular cells may start breaking down much earlier in
life. So, education and preventive actions should begin as early as
possible.
2. Eating certain foods can play a role
in preventing AMD.
TRUE. Research has determined
that two nutrients, lutein (loo-teen) and zeaxanthin (zeeah-zan-thin), may work
as antioxidants in the eyes to help prevent AMD. So, what foods contain
these nutrients? Many fruits and vegetables contain these, but they are in
highest concentration in dark green, leafy vegetables such as spinach, kale, and
collard greens. As well, substances in the yolks of eggs have been proven
to help the body absorb lutein and zeaxanthin. Fish oils may also ward off
AMD.
Avoiding certain fats (vegetable fat, monounsaturated and polyunsaturated fats,
linoleic acid), like those found in processed snack foods like potato chips,
Doritos, and french fries etc. can help lower your risk of developing AMD.
Conversely, taking cholesterol-lowering drugs such as Zocor (a statin) may help
reduce risks.
3. A brimmed hat and sunglasses could
protect you from AMD.
TRUE. Macular cells are very
sensitive to sunlight. Over a long period of time, the sun-damaged cells
can deteriorate the macula, leading to AMD. Light-colored eyes are
believed to be more susceptible to sun damage, as are those who experience
prolonged exposure to ultraviolet (UV) radiation.
4. Smoking increases your risk for
developing AMD.
TRUE. Smoking reduces
protective antioxidants in the eye. Smoking has been proven to more than
double the risk of AMD, and is more than twice as common in people who smoke
more than one pack of cigarettes a day, compared to non-smokers. The risk
remains high for up to 15 years after quitting.
5. Having relatives with AMD means
you're at higher risk.
TRUE. Some research shows that
AMD can be inherited. If you have one or more immediate relatives with
AMD, you may be at higher risk.
6. African-American men are at greatest
risk for AMD.
FALSE. AMD is much more common
in Caucasians than in African-Americans, and females are at higher risk than
males. A woman over the age of 75 is twice as likely to develop AMD as a
man of the same age. Low levels of estrogen in postmenopausal women may
also increase risk for the condition.
New Studies on
Prevention
The Age-Related Eye Disease Study (AREDS), a major clinical trial sponsored by
the National Eye Institute, one of the Federal government's National Institutes
of Health, reports that a dietary supplement with high levels of antioxidants
and zinc reduce the risk of advanced AMD by about 25%. These supplements
also reduce the risk of vision loss caused by advanced AMD by about 19%.
The antioxidants and minerals used by the study researchers were 500 mg of
vitamin C; 400 International Units of vitamin E; 15 mg of beta-carotene; 80 mg
of zinc as zinc oxide; and 2 mg of copper as cupric oxide. Copper was
added to the AREDS formulations containing zinc to prevent copper deficiency,
which may be associated with high levels of zinc supplementation. Where
can you obtain the supplements? Bausch and Lomb was a collaborator in the
AREDS and provided the study supplements. The company markets the
formulation used in the AREDS; other companies provide similar formulations.
All of these supplements can also be purchased separately; however, you should
consult your physician before taking high levels of any of them. Any
drugstore should carry them.
For more information on assessing your personal risk of developing AMD, and how to prevent the disease, visit the Alliance for Aging Research website at: http://www.agingresearch.org. As well, check out the links on the Helpful Links page. Also, contact the National Eye Institute at 301-496-5248 or visit the NEI website at www.nei.nih.gov.
Other Links
http://www.yext.com/macular-degeneration.html
Information and resources for patients with macular degeneration.
http://www.macular-degeneration.org/
Macular Degeneration Organization produced this large-type web site that the
visually impaired will appreciate.
http://en.wikipedia.org/wiki/Macular_degeneration
Wikipedia