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AGE-RELATED MACULAR DEGENERATION

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AGE-RELATED MACULAR DEGENERATION Powered By Docstoc
					Age-Related Macular Degeneration
              And
         Multi-Vitamins


           James L. Combs, M.D.
          Eleanore M. Ebert, M.D.
            Byron S. Ladd, M.D.
          George E. Sanborn, M.D.
            Jeffrey H. Slott, M.D.




      (804) 359-4614 or (804) 282-3931

             www.VaEye.com
           Age-Related Macular Degeneration & Multi-Vitamins
In the United States Age-Related Macular Degeneration is the leading cause of decreased vision
and central visual loss in patients 65 years and older. Prior to October 2001, there was no
treatment for the earlier stages of macular degeneration aimed at slowing the development of
the visual loss that occurs in this condition.

In October 2001, the results of a randomized controlled clinical trial funded by the National Eye
Institute and conducted by the Age-Related Eye Disease Study Research Group (AREDS) were
published. The AREDS study investigated whether the long term use of oral supplement
multivitamins slow the development of visual loss due to Age-Related Macular Degeneration.
The AREDS study showed that the combination of oral antioxidants and zinc taken daily was
modestly effective in reducing the risk of advanced Age-Related Macular Degeneration and
stopping the progression of visual loss in patients with intermediate early stages of Age-Related
Macular Degeneration.

The total daily medications (taken as two tablets twice a day) were:

             Vitamin C 500 mg
             Vitamin E 400 I.U.
             Beta carotene 15 mg
             Zinc 80 mg as zinc oxide
             Copper 2 mg as cupric oxide

These levels of antioxidants and zinc cannot be consumed by diet alone. Copper was added to
the formulation containing zinc in order to prevent copper deficiency which can be associated
with high levels of zinc intake.


Are these levels of antioxidants and zinc safe?

As far as we know, the doses used in the study are safe. Patients in the study were monitored
very carefully and no significant adverse effects were found. Whether these antioxidants and
zinc are safe in all patients is not known. The average follow up in the study was 6.3 years; it is
not known whether taking these doses of antioxidants and zinc for longer periods would be safe.

The one group who should not take beta carotene are patients who are at high risk for lung
cancer. This group includes cigarette smokers and asbestos workers. Two large clinical trials
have shown that significant amounts of oral supplementation with beta carotene raises the risk
of lung cancer in smokers.




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Several studies have shown that smoking is a risk factor for age-related macular degeneration.
All patients who have any degree of macular degeneration should stop smoking. Whether long
term smokers can stop smoking and then begin taking beta carotene safely is unknown.

In all cases, patients who wish to take these levels of antioxidants and zinc should be advised to
consult with their primary care physician before taking any supplements in these doses. The
dose of vitamin C used in this study is about five times what the general population receives
from diet alone, the dose of vitamin E is about thirteen times the Recommended Daily
Allowance (RDA), and the dose of zinc and zinc oxide is about five times the RDA.

What is the role of lutein and zeazanthin?

Lutein and zeazanthin are two other carotenoids that may have some role in the health of the
eye. The theory is that these two carotenoids absorb certain wavelengths of light and therefore
might possibly protect the eye from damage. This is a theory and no proof exists that these
carotenoids in pill form prevent visual loss.

The best advice at the moment is for patients who wish to increase the levels of lutein and
zeazanthin in the eye to try to consume these carotenoids in food. The foods that contain the
largest numbers of these two carotenoids are in descending order: cooked kale, cooked collard
greens, cooked spinach, cooked turnip greens, and raw spinach.

What is the best advice for patients who would like to prevent the advanced
forms of age-related macular degeneration?

The best advice would be to see an eye specialist for a complete eye examination that includes
dilation of the pupils. In some cases, your eye specialist may refer you to a retina sub-
specialist. If the retinal examination shows that you have an intermediate stage of macular
degeneration -- extensive intermediate size drusen, large drusen, or non-central geographic
atrophy -- or if you have advanced Age-Related Macular Degeneration in one eye, you should
consider taking a supplement containing doses of antioxidants and zinc used in this study.

We recommend an overall balanced low fat diet that is rich in fruits, vegetables and fish for
everyone.

How is it possible to obtain these antioxidants and zinc?

As far as we know, only one multivitamin supplement in the dosage used in the AREDS study
is available commercially. That is Ocuvite PreserVision sold by Bausch Lomb. It will be
necessary to take two tablets twice a day. This should be available in pharmacies in the vitamin
section and is available without a prescription. The second option is to obtain one of the
commonly used multivitamins and then purchase separate supplements of each individual
supplement, so that you come up to the required dosage. The third option would be to obtain
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individually the amounts of each separate antioxidant and the zinc and copper. This third
option is the only option that is going to be available for those patients who are smokers and can
not take beta carotene.

Ginkgo biloba and bilberry extract have been promoted for the health of the
eye. Do these agents have any role in maintaining the health of the eye or
preventing ocular disease?

To the best of our knowledge there is no scientific evidence that either of these agents has any
role in the health of the eye.




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