Age-related macular degeneration is a major cause of visual impairment in the U.S. For Caucasians over age 65 it is the leading cause of legal blindness.
Facts on Macular Degeneration
Age-related macular degeneration (AMD) is a leading cause of vision loss in Americans 60 years of age and older. It is also the leading cause of legal blindness among white Americans age 40 and over, accounting for 54% of all such blindness.
Age-related macular degeneration is a common eye disease that causes deterioration of the macula, the central area of the retina. The retina is a paper-thin tissue at the back of the eye where light sensitive cells send visual signals to the brain. Sharp, clear, straight-ahead vision, color and fine detail are processed by the macula, and damage to this area results in blind spots and blurred or distorted vision. When the macula is damaged, many daily activities such as driving and reading become increasingly difficult.
Approximately 1.75 million Americans 40 years and older have advanced age-related macular degeneration, and another 7.3 million people with intermediate age-related macular degeneration are at substantial risk for vision loss.
It is estimated that by 2020 there will be 2.95 million people with advanced age-related macular degeneration.
Currently, it is estimated that as many as 11 million people in the United States have some form of age-related macular degeneration. By 2050, this figure will double to nearly 22 million.
Age is a prominent risk factor for age-related macular degeneration. 3.8 percent of Americans between the ages of 50-59 have either intermediate or advanced age-related macular degeneration; by ages 70-79, this increases to 14.4 percent.
A large study found that people in middle-age have about a 2% risk of getting AMD, but this risk increased to nearly 30% in those over age 75.
Direct medical costs of AMD are substantially higher among the population aged 65 years and older than in the population aged 40 to 64 years.
Other risk factors include: smoking, family history of macular degeneration, gender, obesity, race, prolonged sun exposure, a high fat diet and/or one that is low in nutrients and antioxidants, hypertension, and cardiovascular disease.
There are two forms of macular degeneration: dry and wet.
The dry form of macular degeneration, in which the light sensitive cells of the macula slowly break down, is the most common type, accounting for 90 percent of diagnosed cases.
Wet macular degeneration accounts for approximately 10 percent of cases, but results in 90 percent of legal blindness. It is considered advanced macular degeneration (there is no early or intermediate stage of wet macular degeneration). Wet macular degeneration is always preceded by the dry form of the disease.
It is possible for dry macular degeneration to advance and cause loss of vision without turning into the wet form of the disease; however, it is also possible for early-stage dry age-related macular degeneration to suddenly change into the wet form.
Medicare beneficiaries who had AMD increased from 5% to 27.1% from 1991 to 1999.
On a scale of 1-10, with 10 indicating the greatest impact on daily life, 71% of adults say that loss of eyesight ranks a 10. However, only 52% of adults 18 and older report that they have heard of macular degeneration.
To help diagnose macular degeneration, an eye care professional will perform a dilated eye exam, fundoscopy, a visual acuity test and fundus photography. If wet age-related macular degeneration is suspected, a fluorescein angiography, in which dye is used to detect leaking blood vessels, may also be performed. The patient may also be asked to look at an Amsler grid.
Currently, there is no treatment or cure for advanced dry macular degeneration that will prevent vision loss. However, a specific high dose formula of antioxidant vitamins and zinc may delay or prevent intermediate macular degeneration from progressing to the advanced stage.
Lucentis® (ranibizumab injection), Macugen® (pegaptanib sodium injection), laser photocoagulation and photodynamic therapy are some common treatments that can help control the abnormal blood vessel growth and bleeding in the macula for those with wet macular degeneration. Physicians have also used Avastin™ (bevacizumab injection), a cancer therapy manufactured by the company that makes Lucentis, as an “off-label” treatment for wet macular degeneration.
The injectable medications, such as Lucentis (ranibizumab) are effectively reducing damage from wet AMD; vision stabilizes in over 90% of patients and actually improves in more than 30%.
Vision rehabilitation and low vision aids can help improve the quality of life for those who are visually impaired.
A healthy lifestyle may help reduce the risk of developing macular degeneration. The following are recommended:
Don’t smoke
Exercise regularly
Keep blood pressure in a normal range and control other medical conditions
Maintain a healthy weight
Eat a diet high in fruits, vegetables and fish
Protect eyes from overexposure to sunlight with sunglasses and hats
Ongoing research is exploring environmental, genetic and dietary factors that may contribute to macular degeneration. New treatment strategies are also being investigated, including retinal cell transplants, drugs to prevent or slow disease progress, radiation therapy, gene therapies, a computer chip implanted in the retina that may help simulate vision, and agents that will prevent new blood vessel growth under the macula.
If you have been diagnosed with macular degeneration, don't be afraid to use your eyes for reading, watching TV, and other daily activities. Normal use of your eyes will not increase damage to your vision.
Disclaimer: The information provided in this section is a public service of the American Health Assistance Foundation, and should not in any way substitute for the advice of a qualified healthcare professional and is not intended to constitute medical advice. Although we take efforts to keep the medical information on our website updated, we cannot guarantee that the information on our website reflects the most up-to-date research. Please consult your physician for personalized medical advice; all medications and supplements should only be taken under medical supervision. The American Health Assistance Foundation does not endorse any medical product or therapy.
Source: Some of the information in this fact sheet was obtained from the National Eye Institute.