The Worst That Could Happen? Going Blind, People Say

“Feeling My Way Into Blindness,” an essay published in The New York Times in November by Edward Hoagland, an 84-year-old nature and travel writer and novelist, expressed common fears about the effects of vision loss on quality of life.

Mr. Hoagland, who became blind about four years ago, projected deep-seated sadness in describing the challenges he faces of pouring coffee, not missing the toilet, locating a phone number, finding the food on his plate, and knowing to whom he is speaking, not to mention shopping and traveling, when he often must depend on the kindness of strangers. And, of course, he sorely misses nature’s inspiring vistas and inhabitants that fueled his writing, though he can still hear birds chatter in the trees, leaves rustle in the wind and waves crash on the shore.

Mr. Hoagland is hardly alone in his distress. According to Action for Blind People, a British support organization, those who have lost some or all sight “struggle with a range of emotions — from shock, anger, sadness and frustration to depression and grief.”

When eyesight fails, some people become socially disengaged, leading to isolation and loneliness. Anxiety about a host of issues — falls, medication errors, loss of employment, social blunders — is common.

A recent study from researchers at the Wilmer Eye Institute at Johns Hopkins University School of Medicine found that most Americans regard loss of eyesight as the worst ailment that could happen to them, surpassing such conditions as loss of limb, memory, hearing or speech, or having H.I.V./AIDS. Indeed, low vision ranks behind arthritis and heart disease as the third most common chronic cause of impaired functioning in people over 70, Dr. Eric A. Rosenberg of Weill Cornell Medical College and Laura C. Sperazza, a New York optometrist, wrote in American Family Physician.

Some 23.7 million American adults reported in 2015 that they are unable to see at all or have trouble seeing even with corrective lenses. This number is projected to perhaps double by 2050 based on the aging of the population and increasing prevalence of diseases that can cause vision loss. Yet, the Wilmer Eye Institute’s national study of 2,044 adults found that many Americans are unaware of the diseases and factors that can put their vision at risk and steps they might take to lower their risk.

Perhaps the single most valuable message to emerge from studies of vision loss is the importance of having a thorough eye checkup at least once every two years, if not annually. Many sight-robbing conditions can be effectively treated if detected early enough, in many cases limiting or eliminating the damage to eyesight.

Four eye diseases — age-related macular degeneration, diabetic retinopathy, glaucoma and cataracts — account for most cases of adult blindness and low vision among people in developed countries. Unlike many other ailments associated with aging, they cause no pain and often no early symptoms and thus do not automatically prompt a person to seek medical care. But a thorough checkup by an ophthalmologist can detect them in their earliest stages, followed by treatment that can slow or halt their progression or, in the case of cataracts, restore normal vision.

Macular degeneration, a leading cause of vision loss in Americans 60 and older, involves an irreversible loss of retinal cells that robs people of the central vision needed to read, watch a TV program or identify a face or object in front of them. There are two types, dry and wet. In the dry type, the light-sensitive cells in the macula, a structure near the center of the retina, gradually break down. In the wet type, abnormal blood vessels grow under the macula.

Steps you can take to lower your risk of macular degeneration or slow its progression include not smoking, eating lots of dark leafy green vegetables, wearing sunglasses to block ultraviolet light, and taking one or more supplements formulated to support macular health. There are also treatments specific for wet A.M.D., including laser surgery, photodynamic therapy and drugs that are injected into the eye to slow the growth of abnormal blood vessels.

Diabetic retinopathy, the cause of most blindness in American adults, also affects the light-sensitive retina, damaging the vision of more than half of people with diabetes age 18 or older. The most effective preventive is maintaining a normal level of glucose in the blood through medication and a proper balance of diet and exercise. Blood glucose should be routinely monitored, high blood pressure effectively treated and smoking avoided entirely.

Glaucoma, another leading cause of blindness, involves a rise in fluid pressure inside the eye that damages the optic nerve. It affects more than four million Americans, about half of whom don’t know they have it, and is especially common among African-Americans and Hispanics. It can be detected with a comprehensive eye exam, which should be done annually for African-Americans and those with a family history of the condition.

Although glaucoma is not curable, treatment to lower pressure in the eye with prescription eye drops and, in some cases, pills or surgery can control the condition.

Cataracts are the most common cause of vision loss among people over 40. They involve a gradual clouding of the lens, a normally transparent tissue directly behind the iris and pupil that helps to focus images on the retina. As cataracts progress, it becomes increasingly difficult to see clearly, impairing the ability to read, drive or recognize faces.

Preventing or slowing the development of cataracts involves protecting the eyes from sun damage, not smoking, consuming a diet rich in vegetables and fruits and, if you have diabetes, keeping blood sugar under control.

In years past, doctors often advised patients with cataracts to wait until they were far advanced before removing them surgically. This is no longer the case. Cataract surgery is now done when the condition begins to affect a person’s quality of life or interferes with the ability to perform normal activities.

The surgery is nearly always done under local anesthesia on an outpatient basis. If both eyes have cataracts, as is usually the case, the second eye is typically treated some weeks after the first to avoid the rare risk of a postoperative infection in both eyes. The operation involves removing the clouded lens and, in most cases, replacing it with a clear artificial lens that often gives patients better vision than they had even before developing cataracts.