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At the 2008 Academy of Ophthalmology Annual Meeting, retinal specialists heard more details about progression of AMD. Here is how different risk factors effect your disease and what you can do to slow the progression.

Genetics

Well, you can’t do anything about your genetics, but you can improve your chances even if you do have the genetics for AMD.

Dr. Michael L. Klein presented a report on predicting the progression of AMD based on genetics. In reviewing a study of 1466 people with macular degeneration, 19% progressed to advanced AMD over 6.3 years. The researchers looked at some specific genotypes and how they related to this 19% progression.

It’s possible to look deep within the gene at different “pieces”, called loci, and note the different rates of progression for each loci. Some show progression rates of as low as 5% while others are as high as 40%. When people have more than one of these loci, or have other risk factors like smoking, the progression rate goes up.

What does this mean to you?

If you have macular degeneration, you may have one of these genotypes. Genetic testing is not ready for the general public, so you can’t go out and find out your genotypes. But here is the important news.

If you do have two of these genotypes, and you smoke or have a high body mass index, you have a 19-fold increase in the risk of developing advanced macular degeneration. The message is clear don’t smoke and don’t allow yourself to become overweight.

Vitamin Supplementation

Dr. Emily Y. Chew from the National Eye Institute, presented data from the AREDS (Age-Related Eye Disease Study) regarding progression of AMD. AREDS involved thousands of patients taking a combination of antioxidants and zinc. The formula showed a 25% reduction in the progression of AMD and a 19% reduction in the vision loss. Participants were followed for up to 10 and a half years. Dr. Chew talked about the progression of AMD in those patients. Age, gender and smoking had a lot to do with it.

Not surprisingly, the older they were, the worse their chances. AMD is a disease of age. It has often been noted that women seem to develop AMD more often than men. But once they have it the risk of progressing to the advanced form of AMD does not seem to be greater for women than for men. In the AREDS study, there was only a slight difference in progression to wet AMD and essentially no increase for dry AMD between women and men.

People who entered the study with worse AMD advanced more than people who entered the study with early AMD. In AREDS, the patients were classified at the beginning of the study on a scale that went from having no AMD to having advanced AMD. Having dry AMD with large drusen at the beginning of the study meant a faster progression to advanced AMD than entering the study with just a few small drusen.

Smoking had a major effect. People who were current smokers had the highest rate of progressing to advanced AMD and severe vision loss. People who used to smoke, but had stopped smoking, had a lower rate of progression. But people who never smoked had the slowest rate.

The final factor addressed was whether or not people in the study took the AREDS vitamin. The results showed that for people with wet AMD, it was very effective. For those with advanced dry AMD (geographic atrophy), there was essentially no difference between people who took the vitamins and those taking a placebo.

What does this mean to you?

No one can tell you how fast your AMD will progress or how much central vision you will lose. If you have early AMD, you don't smoke and you take care of all your other risk factors, your AMD may progress very slowly. If you do smoke - and stop now - you may slow down the rate of progression. If you smoke and don't address your other risk factors, you may speed up the progression of your disease.

But remember, every case of AMD is different. Still, it makes sense to "stack the deck" in your favor by following guidelines for nutrition and general health.

If you smoke, stop!

If you are not taking a vitamin supplement, ask your doctor about an AREDS supplement or other choices.