By John T. H. Mandeville, M.D., Ph.D. and Gerri L. Goodman, M.D.
John T. H. Mandeville, M.D., Ph.D. and Gerri L. Goodman, M.D.
Impaired vision can occur at any time of life, but eye disorders dramatically increase with age. Four conditions – cataracts, macular degeneration, glaucoma, and diabetic retinopathy - are particularly prevalent and together affect nearly 37 million adults over age 40 in the U.S. according to Prevent Blindness America. And with an aging population, the frequency of these conditions is only expected to grow.
Here’s some basic information about these four common disorders.
Cataracts, affecting 24 million people, are a normal part of aging, but occur at different rates and to different degrees, depending on risk factors. It is a condition in which the lens of the eye deteriorates, resulting in blurred or cloudy vision. Among the causes are overexposure to ultraviolet light and trauma (a blow to the eye or head). Cataracts may also result from some medications, and some people may be genetically predisposed to the disorder. Treatment should occur when it begins to affect “functional vision” and interfere with daily activities. The only remedy is surgery, a common outpatient procedure that replaces the lens in the eye with an implant. Glasses may or may not be needed following surgery. While easily treated in the U.S., cataracts are the primary cause of preventable blindness in the world.
Macular Degeneration alters a person’s central vision and occurs when the blood vessels behind the retina begin to leak. Age-related macular degeneration (AMD) affects more than two million people and has two forms. The “dry” form, accounting for 90 percent of the cases, progresses slowly and is characterized by deposits that form in the back of the eye. The “wet” form, when vessels in the eye bleed, is more serious and can cause sudden vision loss. AMD is more common in Caucasians and is correlated with age: it’s rare in people under 50 and can progress rapidly in those 65 and older. Smoking and a poor diet, particularly one lacking in antioxidants, are contributing factors. The “wet” form is treatable with injections; the “dry” form lacks therapies at this time.
Glaucoma affects the optic nerve and impairs a person’s peripheral vision. It can be diagnosed early with noninvasive tests, and treatments can be customized for individual patients. Diagnosis and treatments (drops, lasers, and surgery] have improved in recent years, so the incidence of blindness from glaucoma is not as high as it once was. Glaucoma remains, however, a major cause of irreversible blindness: once vision is lost, it can’t be reversed, so early diagnosis is critical. The condition currently afflicts three million people and is more common in African Americans and Hispanics than in others.
Diabetic Retinopathy strikes people with diabetes and is correlated with how long a person has had the disease: the longer one has had diabetes, the more likely it is that diabetic retinopathy will occur. The condition affects the blood vessels in the back of the eye and can cause blurring, distortion, or loss of vision due to bleeding inside the eye. Patients should see an eye physician as soon as they are diagnosed with diabetes. It can be treated with lasers and surgery. Diabetic retinopathy is the second most prevalent age-related eye disease, reaching almost eight million adults.
Eye disorders or injuries, of course, are not restricted to those over 40. We recommend that everyone, regardless of age and particularly children who may have a family history of eye problems, get a “baseline examination” that includes dilating the eyes. (Dilation, a painless procedure that widens the pupils with eye drops, gives health professionals the most comprehensive view of all parts of the eye.) People who experience changes in vision or notice eye problems should see an eye care professional as soon as possible.
Prevention is important. Wearing sunglasses to protect against damage from ultraviolet rays and wearing safety glasses or goggles when participating in sports or working with power tools are prudent habits to adopt. We also suggest that patients check their own eyes periodically. Most people don’t realize they may have a problem in one of their eyes until the good eye is covered. The biggest risk factor for damage to one eye is already having damage to the other eye.
There’s not much we can do about getting older, but we can guard our gift of sight by practicing good eye health and getting regular exams. For more information, visit the American Academy of Ophthalmology at www.geteyesmart.org. For a video discussion, visit
John Mandeville, M.D., Ph.D. and Gerri L. Goodman, M.D. are physicians with Eye Health Services, based in Quincy, Mass. Dr. Mandeville is president of the Massachusetts Society of Eye Physicians and Surgeons, and Dr. Goodman is a member of the Society’s Board of Directors. Physician Focus is a public service of the Massachusetts Medical Society. Readers should use their own judgment when seeking medical care and consult with their physician for treatment. Send comments to PhysicianFocus@mms.org