(This article was published in The Hueneme Pilot newspaper 11/05/09)
Age-related macular degeneration (ARMD) is the #1 cause of blindness among Senior Citizens. Because the Baby Boomers are now becoming seniors, vision loss from macular degeneration is a growing problem. About 1.75 million Americans have ARMD now and it’s projected that it might affect 3 million Americans by 2020. Approximately 300,000 will become legally blind.
Although anyone can have it, ARMD occurs most often in Caucasian females over age 65. Smoking increases the risk 6 times and living with a smoker doubles your risk. Being overweight also can double your risk. Another big risk factor is the excessive light exposure that surfers, sailors, farm workers, etc are exposed to.
Most of our retina (the light sensitive tissue inside the eye) has light sensing cells called “rods”. They are very sensitive at light detection but not very sensitive to details. The macula is the 3/16” area of the central retina with light sensing cells called “cones”. They are very sensitive to visual detail and color perception. The macula supplies the straight-ahead vision. In macular degeneration the macular cells are damaged and central straight-ahead vision becomes blurred or distorted.
ARMD sometimes begins with a build-up of cellular waste products in the cone cells called drusen. Also there may be a change in the amount of pigmentation in the cell (like the “age-spots” on our skin with aging). This is referred to as “Dry ARMD”. Over time vision slowly worsens and over many years may lead to significant vision problems. Ten percent of these patients progress to “Wet ARMD” in which new blood vessels grow in below the macula and then leak blood into the macula. The resulting scarring leaves areas of the macula that are blind. Many of these patients are legally blind.
There is no medical treatment available for Dry ARMD, but in 1999 A National Eye Institute study (AREDS) indicated that certain nutrients such as beta-carotene (vitamin A) and vitamins C and E help prevent or slow progression of dry macular degeneration by up to 25%. There are several brands of AREDS formula supplements available without a prescription. Some varieties also include lutein, an antioxidant found in green leafy vegetables, which has been shown to possibly slow the progress of ARMD.
But there might be a problem with AREDS supplements. Physicians have noted that individuals that have a diet rich in yellow, orange and red fruits and vegetables have a decreased incidence of cancer. These foods contain high concentrations of beta-carotene. In a large study (CARET) in 1992, individuals were placed on beta-carotene supplements to see if that would reduce the cancer incidence. The study was halted prematurely 4 years later because the study participants had a 28% higher incidence of lung cancer, and a 17% increase in death from any cause. Smokers, ex-smokers and others at risk for lung cancer should not take beta-carotene supplements, but should increase their dietary intake of beta-carotene rich fruits and vegetables.
Phase two of the AREDS study began in 2008. It is trying to determine if omega-3 supplements have a protective effect against ARMD. The study is not due to be completed until 2012, but most researchers think that omega-3 will be shown to be beneficial. If I had macular degeneration, or it was in my family history, I would take a supplement containing Omega-3, as well as vitamins C and E, but not vitamin A.
The circulation area of this newspaper, “The Hueneme Pilot”, includes 50,938 people. That means approximately 1,875 Of our neighbors have AMD with vision loss and possible blindness. My next article will discuss the exciting new treatments that can slow the advance of “Wet ARMD”.
Dr. Don Steensma has practiced optometry in the City of Port Hueneme for 33 years. His office is located at 465 W. Channel Islands Blvd in Port Hueneme. For more information call 486-3585 or go on-line to www. visioneyedoctor.com
