Macular Degeneration 101
February is Age-Related Macular Degeneration & Low Vision Awareness Month. Today we’ll focus on the basics regarding Age-Related Macular Degeneration (AMD), including important risk factors and lifestyle choices that can improve your odds against it.
What is AMD?
Before we can discuss this debilitating disease, I think a brief anatomy lesson is warranted. The macula is one of the most important parts of, not only the retina, but of the entire eye. Although, clinically, only about 1.5 mm across (about ⅟₁₆ of an inch; roughly the thickness of a penny), it is responsible for our entire central or “straight ahead” vision. What makes the macula unique is that it has the highest concentration of light-sensing cells, called photoreceptors. This makes it the only part of the human eye capable of seeing 20/20.
Photoreceptors are highly active cells. They require significant amounts of nutrients and a way to actively eliminate metabolic waste. One of more vital structures in this process is a layer of cells called the retinal pigmented epithelium (RPE). AMD begins by causing abnormal changes to this layer of the retina. As an area of RPE is compromised, other surrounding cells (including photoreceptors) become increasingly prone to damage. This cascade of events can lead to anything from mild cell dysfunction, to vision-threatening bleeding and scarring, or even large areas of cell death. Each stage resulting in increasing levels of permanent vision loss.
AMD is a multifactorial disease. This list is by no means comprehensive, instead it highlights a few of the major risk factors.
Age – As the name implies, one of the greatest risk factors for developing AMD is time. As we get older, other risk factors can have an accumulative effect on the health of the retina, which can lead to the eventual manifestation of the disease. In general, AMD is most common over the age of 50.
Genetics – Family history of AMD increases your predisposition for developing the disease. In general, Caucasians are at slightly higher risk than most other races.
Smoking – Numerous studies have noted that smoking not only can lead to the development of AMD, but also significantly increases the likelihood of progression once you have the disease.
Health Status – Heart disease, high blood pressure, high cholesterol levels, diabetes and obesity are bad for overall health. Few people know they are just a few of the systemic conditions linked to AMD.
Not all risks are modifiable. This is a short list of a few things you can do to reduce your risk of developing AMD. If you already have the disease, these same tips may improve your odds of slowing the rate of progression.
Make healthy choices
Healthy eyes start with a healthy body. Stay up to date with your general health by having regular visits with your primary care physician. Avoid smoking or being around people that smoke. Last, but not least, don’t forget your eye exam!
Unhealthy eating has not only been linked to the development of AMD, but to increased odds of reaching advanced stages of the disease. Studies have shown that eating foods rich in carotenoids (antioxidants such as lutein and zeaxanthin), may help reduce the risk of AMD progression. Good sources of these antioxidants include many green, leafy vegetables such as: kale, spinach, chard and collard greens. Added supplementation with ARED 2 vitamins may be beneficial at certain stages of the disease. *Ask your eye doctor for more information.
Just like SPF is important for the skin, wearing the proper lenses when outdoors can reduce the sun’s damaging effects on the retina. Not all sunglasses are created equal. The best protection will come from lenses rated UV400 or higher, which filter at least 99.9% of UV rays. There are also UV-filtering options for your everyday clear lenses and, to a lesser extent, contact lenses. *Ask your optometrist or optician for more information.
While AMD can lead to severe loss of central vision, it is possible for early stages of the disease to go undetected for many years, without proper eye care. The best form of prevention is knowledge. Know your habits, know your risk factors, and know Your Eyes! Early detection is crucial.