Many of us take our ability to read this blog or see the faces of our families and friends for granted. For the 10–15 million Americans with a disease called age-related macular degeneration (AMD), however, the loss of this ability is a daily and devastating reality. AMD is the most common cause of blindness in people over the age of 60.
There are many causes of visual impairment, including near-sightedness, far-sightedness, infection and diabetes. Some of these can be relatively easily corrected with eyeglasses and other medical tools and procedures. AMD currently has no cure, and we are just beginning to understand its causes.
AMD is a gradual and progressive deterioration of the retina, the light-sensing tissue at the back of the eye. The disease affects the most sensitive portion of the retina called the macula. We use the macula to distinguish fine features and colors, and when we lose this function, it can be devastating. AMD slowly causes the photoreceptors—cells that make up the retina—to die, creating blank spots in the field of vision. This occurs when undigested deposits of molecular debris called drusen accumulate in an area that eventually starves the cells that support the photoreceptors.
Genetics is the main factor that makes you more likely to get AMD. Other causes may include smoking and an unbalanced diet. Avoiding smoking and making healthy dietary choices are good ways to reduce your risk of AMD. A recent study published in the journal Cell Stem Cell found that a substance related to vitamin B3 reduced molecular debris and inflammation related to AMD in patients with the disorder. Fish, meat, peanuts and green vegetables all contain vitamin B3.
As the U.S. population grows older, diseases such as AMD are likely to become more prevalent and have a higher social and economic burden than they did in the past. Researchers are actively working to better understand the causes of the disease and how to treat and prevent it.
February is Age-Related Macular Degeneration and Low Vision Awareness Month. If you haven’t had your eyes checked yet this year, now is a good time to make that appointment.
Grant Kolar, MD, PhD, is an assistant research professor of pathology and ophthalmology at Saint Louis University School of Medicine.