Age-Related Macular Degeneration (AMD) is the leading cause of vision loss for people over the age of 60 in the United States. Over 1.65 million American have it, and it’s characterized by the loss of central vision in one or both eyes.
February is the AMD/Low Vision Awareness Month. In this post, we discuss what AMD is, who is at risk, the symptoms to look out for, and treatments to seek before the condition gets worse.
AMD damages the macula, which is a spot near the center of the retina. It’s the part of the eye responsible for giving us clear, a sharp central vision that lets us see the objects right in front of us.
The macula is composed of millions of light-sensing cells and is the most sensitive part of the retina. The function of the retina is to convert electrical signals, send them through the optic nerves and translate the objects into images, to the brain.
A damaged macula will give your central field of vision a blurry, dark, or distorted image. It’s not going to be solely responsible for blindness, however. But it can interfere with your daily activities, such as reading, writing, doing work that requires close range and precision like cooking and driving.
A study conducted by the U.S. Centers for Disease Control and Prevention (CDC) and the University of Wisconsin School of Medicine and Public Health, around 6.5 percent of Americans over the age of 40 already suffer from some degree of AMD.
On the other hand, some research indicates that in 2010 alone, there were already 9.1 million cases of AMD that manifested before the age of 60. These early cases are expected to affect 17.8 million by 2050.
There are two types of AMD: wet and dry.
The former also called the neovascular type, affects around 10 to 15% of people with age-related macular degeneration. However, it’s responsible for over 90% of severe vision loss. In this condition, abnormal blood vessels under our retina will transfer and grow towards the macula. Since these blood vessels are out of the norm, they will break and leak fluid, which will damage the macula and cause it to break apart from its base. This is how rapid central vision loss occurs with wet AMD.
On the other hand, dry, or atrophic age-related macular degeneration affects the majority of individuals with AMD, between 80 to 90%. It causes small, white or yellowish deposits beneath the macula. It progresses slower than the neovascular type and has no known treatment or cure.
AMD is generally slow and painless in its progression, particularly dry AMD. It can take years to progress while generally affecting your central vision. On the other hand, the wet type can come suddenly and cause drastic changes in your vision.
Among the earliest signs of AMD to watch out for are shadowy areas in your central vision, distorted images or vision, difficulty seeing things that are some distance away, inability to make out the details of faces, images or words on a page, and blank spots in your central vision.
A telltale symptom of wet AMD is straight lines appearing as wavy, while dry AMD symptoms blur out the central vision.
The Amsler grid is one of the most popular means of determining vision problems. It consists of straight lines on a grid with a dot on the center. If you have macular degeneration, the lines might appear distorted, wavy, or blurred.
AMD is common in white females and has been found to run in families. Apart from its hereditary factors, it can also be a side effect of smoking, high blood pressure, obesity, and drugs. Let’s discuss them one by one.
The most common cause of AMD is age. In the United States alone, one in 14 people over 40 years old have AMD, and those over the age of 60 have a one in eight chance, while seniors over age 80 have a one in three chance.
When it comes to genes, if you have a relative who also suffered from AMD, chances are you are also at risk of getting it. Studies conducted on fraternal and identical twins determined that heredity plays a role in who eventually develops AMD and its level of severity.
People who are overweight, obese, and have sedentary or inactive lifestyles also put themselves at risk of developing more complicated and advanced forms of macular degeneration, compared to those who maintain a healthy, normal weight.
Smoking has been found to have a direct link to 25 percent of AMD cases that lead to severe vision loss, according to a study published in the British Journal of Ophthalmology. And to top it off, people who experience secondhand smoking have double the risk of getting AMD.
In some cases, macular degeneration can come from the side effects of anti-malarial and anti-psychotic drugs such as Aralen, Thorazine, Mellaril, Trifalon, and Stelazine.
There is no known cure yet for AMD, and treatments for AMD commonly include nutritional and lifestyle adjustments, and FDA-approved drugs.