Many eye diseases are treatable if diagnosed early enough. But often the damage from eye disease happens slowly, so a person doesn’t notice a loss of vision until it is too late. Vision loss can lead to depression, inactivity and overall decline in seniors.
The top cause of impaired eyesight in older adults is age-related macular degeneration. With the aging of our population, protecting against this vision-destroying condition is vital to keeping our senior population as independent and healthy as possible.
What is age-related macular degeneration?
Age-related macular degeneration (AMD) is the deterioration of the center area of the retina of the eye. The retina is the layer of tissue at the back of the eye that “sees”—that is, transmits images to the brain through the optic nerve. The center area of the retina, called the macula, is responsible for the sharp central vision we use for reading, driving, working a puzzle, sewing and so many other tasks.
There are two forms of macular degeneration:
Dry AMD occurs when the tissue of the retina thins and deteriorates. The light-sensitive cells break down, and central vision gradually becomes blurred. Dry AMD is associated with the appearance of drusen, small yellow deposits under the retina.
Wet AMD, also called neovascular AMD, is caused by abnormal blood vessels growing under the retina. These new vessels are very delicate, and begin to leak blood and fluid behind the retina. This damage can occur quickly.
What causes AMD?
The causes of AMD are not entirely understood. But we know that the thinning of the macula and the development of abnormal blood vessels behind the retina are in part the result of wear and tear on our body systems. Indeed, age is the top risk factor for developing AMD. Other risk factors include a family history of the disease, race (Caucasians are at highest risk), smoking, and medical conditions such as obesity, high blood pressure, high cholesterol and certain immune disorders.
How is AMD diagnosed?
In the earliest stages of the disease, the patient may not notice anything is amiss. Dr. Ahn-Danh Pham of the Indiana University School of Medicine says that all adults should be alert for any subtle changes in their vision. Dr. Pham, a retinal specialist, says, “As with most age-related vision problems, many people are unaware of slight vision losses and don’t realize that their vision has been compromised until it is too late.”
The signs of dry AMD include blurred vision, a blank spot in your visual field, and trouble reading or recognizing faces. You might notice that you need a brighter light for reading or that night driving is more of a challenge.
Wet AMD comes on more suddenly. The most common symptom is distorted vision. Straight lines appear crooked, and dark gray or blank spots may appear in your vision. This is because the blood and fluid leaking from the abnormal blood vessels push the macula out of position.
If you notice any of these signs, alert your eye care professional right away. He or she will dilate your eyes with special drops that open the pupil so the back of the eye can be seen. The doctor will look for drusen, the small yellow deposits over the back of the retina that are associated with dry AMD. Other tests allow the doctor to see the abnormal blood vessels of wet AMD.
In the early stage of the disease, our brains do a pretty good job of “working around” subtle vision loss. Especially if AMD is only present in one eye, the other eye will compensate. So routine dilated eye exams are important, to allow the doctor to detect AMD even before the patient notices any symptoms.
Can AMD be cured or treated?
Treatment for wet AMD consists of laser surgery; slowing or stopping the leaking of blood vessels by means of injections; or photodynamic therapy, a procedure that uses a combination of light and drugs. The National Eye Institute says that these treatments can help slow down vision loss and in some cases improve sight. But none of these treatments are a cure for the disease, and vision loss may continue despite treatment.
There is no treatment to reverse dry AMD. The goal, instead, is to prevent the condition from progressing to a more advanced stage. Certain lifestyle changes may prevent or delay further vision loss. These include having an annual eye exam, managing high blood pressure and cholesterol, exercising regularly, and avoiding smoking and second-hand smoke.
Nutrition is especially important. According to Prevent Blindness America, a wide variety of foods, including lentils, grapes, carrots, bell peppers, broccoli, spinach, sweet potatoes, kale, certain kinds of fish, turkey and some kinds of nuts, have been shown to aid eye health. Foods that contain refined starches and are high in sugar can be damaging to vision.
What about vitamins?
The National Eye Institute has conducted a series of important studies on the effect of nutrition on AMD. Certain nutrients were found to be protective against the development and progression of AMD, including vitamins A, C and E and zinc. The Institute continues to refine this research. It is a challenge to get the levels of these nutrients from diet alone. Ask your eye doctor whether you should take supplements containing these nutrients. (Be sure to tell your other healthcare providers that you are taking these vitamins; if you are already taking a multivitamin, the formula may need to be changed to avoid a higher-than-recommended dose of certain vitamins.)
Living with AMD
People with age-related macular degeneration can make the most of their remaining vision with special training and technologies. Ask for a referral to a low-vision specialist for instruction on how to compensate for the vision that is lost. Many community organizations and agencies offer information and services such as:
- Training on new ways of doing things
- Low-vision adaptive devices such as hand or stand magnifiers, magnifying spectacles, video magnifiers, screen readers, and special computer programs and equipment
- Large-print books or audiobooks
- Home modifications, including improved lighting
- Alternate transportation when it is unsafe to drive
- Support groups where people with low vision can exchange ideas and share experiences
- Information about new research on treatments and vision-enhancement devices
The National Eye Institute also reminds seniors: “If you have lost some sight from AMD, don’t be afraid to use your eyes for reading, watching TV and other routine activities. Normal use of your eyes will not cause further damage to your vision.”
For More Information
The National Eye Institute offers consumer information [link to: http://www.nei.nih.gov/health/maculardegen/index.asp] about AMD and living with low vision.
Visit the Eye Care America [link to: http://www.geteyesmart.org/eyesmart/diseases/amd.cfm] website, sponsored by the American Academy of Ophthalmology, which offers consumer information [link to: http://www.geteyesmart.org/eyesmart], free eye exams and ideas for living successfully with vision loss [link to: http://www.geteyesmart.org/eyesmart/diseases/upload/SmartSight_handout.pdf ].
The information in this article is not intended to replace the advice of your doctor. Talk to your eye healthcare provider if you have questions about vision care, the AREDS formula vitamins or other eye care issues.
Copyright © AgeWise, 2014