Age-related macular degeneration (AMD) is the leading cause of vision loss in older adults, affecting more than 10 percent of those over the age of 75. There are two types of AMD: dry (atrophic) and wet (exudative/neovascular). Today, Dr. Kanoff will address dry AMD.
“Dry AMD is the most common form of AMD, accounting for about 85 to 90 percent of cases,” Dr. Kanoff stated.
Over a period of years, AMD can progress through three stages:
- Early – You are unlikely to notice any symptoms at this stage, which is characterized by the presence of medium-sized drusen (yellow deposits beneath the retina).
- Intermediate – At this stage, you may notice some minor vision changes, along with larger drusen and/or pigment changes in the retina.
- Late – At this stage, there is severe vision loss.
“Since In its early stages AMD does not have any symptoms, a comprehensive dilated eye exam of the back of the eye is the only way to diagnosis it,” Dr. Kanoff said.
As the disease progresses, you may experience:
- Wavy or blurred vision
- Visual distortion such as straight lines for sentences on a page appearing bent
- Extra sensitivity to glare
- Loss of color vision or intensity
- Difficulty seeing details in low-light levels
- Problems recognizing faces
Treatments to slow vision loss
Dr. Kanoff said, “Even though there are no cures for dry AMD, a special combination of nutritional supplements can potentially slow down the disease’s progression.”
Two large clinical trials conducted by the National Eye Institute (NEI)—the Age-Related Eye Disease Study (AREDS; 2001) and a follow-up study called AREDS2 (2013)—found that a special formula of nutritional supplements could reduce an AMD patients’ risk of progressing to the advanced stage by about 25 percent over a five-year period. So far, there is no evidence that supplements benefit the patients in the early stage.
However, the original AREDS formula included beta carotene, which was later found to be linked to a higher lung cancer rates in smokers. In the follow-up AREDS2 study researchers examined the formula without beta carotene, replacing it with antioxidants lutein and zeaxanthin and lowering the zinc content.
The AREDS2 special formula includes:
- Lutein (10mg)
- Zeaxanthin (2mg)
- Vitamin C (500mg)
- Vitamin E (400IU)
- Zinc (80mg)
- Copper (2mg)
“Although both AREDS and AREDS2 formulas are available over the counter, it’s best to consult your doctor before you start taking either of them. Determining the best formula for you depends on your medical history, type of AMD and stage of the disease,” Dr. Kanoff said.
If you’ve been diagnosed with AMD, Dr. Kanoff said that you may be given an Amsler Grid to use at home as an early warning system for changes in your vision. You’d view the grid and check to see whether lines on it look wavy or distorted, or whether areas of the grid are missing.
View Powerpoint slides from Dr. Kanoff’s lecture for the Boulder Community Health System’s Community Education series on “Advances in Treating Macular Degeneration.”