Age-Related Macular Degeneration

Are You at Risk for AMD? Learn the Top 5 Risk Factors

Age-related macular degeneration (AMD) is a leading cause of severe vision loss among Americans ages 65 and over. Knowing your risk factors, being aware of your family history, and keeping regular appointments with your Eye M.D. can help reduce your risks for vision loss from macular degeneration. In its most severe form, known as wet AMD, the disease can lead to permanent loss of central vision, which is essential for driving, reading and recognizing faces.

“The past few years have been marked by significant improvement in understanding the causes and the treatment of AMD,” says Dr. Jason C. Cheung, MD. “New research and clinical advances are helping us to better treat both the ‘dry’ and ‘wet’ forms of AMD. One strong risk factor that people may not be aware of is family history. It’s important to find out whether your relatives have had AMD and to tell your Eye M.D. if you have a history of AMD in your family. Knowing your risks can save your sight.”

Here are the top 5 risk factors for AMD:

  • Being over the age of 60
  • Having a family history of AMD
  • Cigarette smoking
  • Obesity
  • Hypertension

If you have any two of these risk factors, you should schedule an appointment with your Eye M.D for a complete evaluation. Your Eye M.D. may recommend certain preventive measures that can reduce your risk of vision loss from this disorder.

People who are at risk should know the symptoms of wet AMD, the form most likely to cause rapid and serious vision loss. These include sudden, noticeable loss or distortion of vision, such as seeing “wavy” lines. See an Eye M.D. right away if these symptoms occur. Current treatments for wet AMD provide an excellent chance of stopping vision loss and may actually restore some vision when macular degeneration develops. Earlier diagnosis of wet AMD gives a better chance of successful treatment.

There are some AMD risk factors that a person can change, such as smoking and diet, to reduce the risk of vision loss from AMD. Other risk factors, such as genetic factors, cannot be changed. However, knowing your family medical history is one way to learn whether you may be genetically predisposed to a disease. One way to reduce AMD risk is to quit smoking or never start. For patients at high risk for developing late-stage AMD, taking a dietary supplement of vitamin C, vitamin E and beta carotene, along with zinc, has been shown to lower the risk of AMD progressing to advanced stages by 25 percent. Patients should check with their Eye M.D. before starting any dietary supplement.

About AMD

The disease takes two forms, termed “dry” and “wet.”

  • Early-stage AMD: Yellow deposits called “drusen” develop under the retina, the light-sensitive tissue at the back of the eye that focuses images and relays them to the optic nerve. At this stage, most people would do not have reduced vision.
  • Intermediate AMD: Patients have more and larger drusen and more pigment changes in the macula (the part of the retina responsible for central vision); they are at higher risk for both advanced dry and wet AMD. The majority of those with intermediate AMD do not progress to an advanced stage, but should be followed by an Eye M.D. so they can be treated if needed.
  • Advanced “dry” AMD: Patients with more advanced dry AMD may have a blind spot in their central vision. Currently, there is no proven therapy to restore vision lost from advanced dry AMD. Low-vision technologies, including improved lighting and magnification, help people with advanced dry AMD maintain their quality of life.
  • Advanced “wet” AMD: In this stage, abnormal blood vessels form under the retina. These blood vessels can leak fluid or bleed and cause sudden and drastic loss of central vision.

Although only about 10 percent of the 10 to 15 million Americans with AMD have the “wet” form, it is responsible for most severe vision loss. New, highly effective treatments such as the injectable medications ranibizumab and bevacizumab are dramatically reducing damage from “wet” AMD and can stabilize vision in more than 90 percent of patients and actually improve vision in up to 30 to 40 percent of patients. A newly FDA-approved implantable miniature telescope (IMT) has the potential to improve the quality of life for select patients with AMD. Though this device is not for everyone, it does include people aged 75 years and older who have stable, severe to profound vision impairment in both eyes due to end-stage AMD. Also, to be eligible for the IMT, patients cannot have had surgery to remove cataracts. Patients also need to be fully informed of the risks of the procedure – most importantly, the risk of corneal endothelial cell loss, which may cause long-term problems with corneal clarity.