Everything you need to know about macular degeneration

Many of us are painfully aware of our body's increasing number of shortcomings as we get older. Sagging skin, hearing loss, receding hairlines and tending to use the bathroom more frequently than we used to.

But one of the most dreaded adverse outcomes is that of diminishing eyesight. Reduced vision, also known as vision impairment, is so common that research shows that nearly 30% of U.S. adults 71 and older have it. While many factors can contribute to it occurring, the leading cause of vision loss in older adults is age-related macular degeneration, according to the U.S. Department of Health and Human Services Office of Disease Prevention and Health Promotion.

Here's what macular degeneration is, what causes it and how you can expect it to be treated if it affects you or a loved one.

What is macular degeneration? What is AMD, wet AMD?

Macular degeneration, also known as age-related macular degeneration or AMD, is an incurable eye disease that damages the middle part of the retina that's known as the macula, "which is responsible for our central, detailed vision," explains Laura Di Meglio, OD, an assistant professor of ophthalmology at the Wilmer Eye Institute at Johns Hopkins University School of Medicine.

When this area of the eye is damaged, it leads to a gradual loss of sharp central vision, seeing dark spots, distorted or wavy vision and difficulty seeing colors. In these ways, "AMD can severely impact quality of life by making it harder to see fine details even though it doesn’t cause total blindness," says Inna Lazar, a Connecticut-based optometrist and founder of Greenwich Eye Care.

Some such adverse impacts include difficulty driving or with close-up activities like reading, writing, cooking, sewing or fixing things around the house. People with AMD can even have problems recognizing faces, Lazar says.

Symptoms vary though as there are two types of AMD: dry AMD and wet AMD. "Dry AMD is very common with about 80% of people with AMD having this form," says Dr. Purnima Patel, an ophthalmologist at ORA Vision in Georgia and spokesperson for the American Academy of Ophthalmology. It is characterized by the macular gradually getting thinner with age. "Wet AMD is less common, but affects sight much quicker," says Patel. It occurs when abnormal blood vessels grow in the back of the eye and damage the macula.

In case you missed: Here's why it's so important to catch and treat glaucoma early

What causes macular degeneration?

More than 20 million Americans have AMD, per the American Macular Degeneration Foundation, but your risk of developing it significantly increases with age. Aging is the single biggest contributor of AMD, in part, because cell regeneration slows down as we get older, which is one of the highest risk factors associated with diminished eyesight.

Several other factors are also thought to contribute to the development of AMD. These include a family history of the condition, your race (Caucasians have been shown to be at higher risk, Patel says), and environmental factors such as "smoking, excessive UV exposure, poor diet, high blood pressure and obesity, all of which can damage the delicate blood vessels that nourish the macula," says Lazar.

Elsewhere in eye issues: Kids' eyesight is getting worse. Special contact lenses may be the answer.

How is macular degeneration prevented and treated?

No matter which associated risk factors you may be facing, there are ways of preventing or at least diminishing the worst outcomes of the condition. These include "making healthy lifestyle and dietary choices like eating leafy greens and omega-3s, quitting smoking, staying active and keeping your blood pressure in check," says Lazar.

Once AMD has been diagnosed, a handful of treatment options are available depending on which type of AMD you're dealing with. "To treat wet AMD, ophthalmologists usually use medications called anti-VEGF drugs," says Patel. She explains that anti-VEGF drugs are delivered through a very thin needle and can help stop the leaking of the vessels. "This can slow or stop worsening of the vision and can often even improve vision," she explains.

It's best to consult with your eye care professionals about the best courses of action, especially if you notice symptoms worsening. "It is important for patients with macular degeneration to routinely check their vision in each eye," adds Di Meglio, "and to notify their eye care provider if they notice any changes as quick treatment can help prevent further irreversible damage."

This article originally appeared on USA TODAY: What is macular degeneration?