Age-related macular degeneration (AMD) is a common cause of blindness in the elderly. New drugs are being tested to work against vascular endothelial growth factor (VEGF), a natural chemical in the body that causes neovascularization (the growth of new blood vessels) in the eye.
Corticosteroids, which prevent the growth of new blood vessels, are used against “wet AMD.”
Photodynamic therapy (PDT) is frequently used with other therapies.
Several new therapies, including gene therapy, are in the future.
Preventive measures are limited. According to the Age-Related Eye Disease Study (AREDS), a combination of vitamin C, vitamin E, beta-carotene and zinc reduces the risk of going from early to late stage disease. Lutein and zeaxanthin supplements for increasing the macular pigment density in the eye need further study.
CONCLUSION: AMD is being increasingly treated with pharmaceuticals that work against VEGF. Several new therapies are available and several are in the future. A combination of vitamins C, E, and beta-carotene with zinc seems to reduce the advance of the disease. Lutein and zeaxanthin may improve pigment concentrations but need further study.
NOTE: This summary was based on the abstract, only. The complete article is not available at this time.
There are two types of AMD called dry and wet. Dry AMD is usually seen at the onset of AMD. Small spots are found on the area of the back of the eye on the retina and there may be no visual loss. Wet AMD accounts for the 10% of AMD, which is more severe. The macula (the back of the eye important for sharp focus) is involved in wet AMD with the overgrowth of new blood vessels. Since the macula is not involved in lateral vision, lateral vision may be retained in AMD.
Photodynamic therapy (PDT) is used to treat wet AMD and cancer. A chemical is given to the patient, which can be stimulated by a specific wavelength of light. A light emitting the proper wavelength (usually visible or infrared) is focused on the site to be treated after the chemical is given to the patient. One theory is that this works by destroying blood vessels.
VEGF is a factor that causes the growth of new blood vessels. Therapy that reduces new blood vessel growth can reduce the growth of cancerous tumors. Please see summary #128 for more information about VEGF. VEGF plays a role in cancer growth by making new blood vessels to provide circulation for new cancer cells.
There are nutritional supplements which block VEGF listed in summary #81 as follows: Silymarin (milk thistle extract), DIM, glycine, green tea extracts, selenium, zinc, and fish oil. These products have been tested against the VEGF effects in cancer but, we do not have the same information on testing in AMD.
Lutein and zeaxanthin are both carotenes believed to help AMD. Sufficient evidence is seen to warrant further testing. Read about foods containing lutein and zeaxanthin. Corn products contain lutein and zeaxanthin.
To read the author’s abstract of the article click on the link to the author’s title of the article above.
PMID: 16724865.
Summary #137.
