Saturday, July 27, 2013

Macular Degeneration Update


Macular Degeneration Update
The National Eye Health Institute recently released results from second Age Related Eye Disease Study.  AREDS2 evaluated the effectiveness of specific antioxidants, zinc, and omega-3 fatty acids on halting the progression of macular degeneration.  The following is intended to provide you with information about this disease and steps you can take to preserve your vision.
 
What is macular degeneration?       
The macula is the most sensitive part of the retina.  It is located centrally and is host to the highest concentration of photoreceptors in your eye.  Because of this fact, the macula is responsible for processing light rays that result in our most detailed vision.  When the photoreceptors are damaged, they expend waste products that cause the macular tissue to die or degenerate.  This situation can lead to difficulty when driving, reading, or looking at faces.
 
What vision may be like with macular degeneration.
 
Who is at risk for macular degeneration?
We are all potentially at risk for development of macular degeneration.  It is an age related disease and is the leading cause of blindness among Americans aged 60 and older.  Currently, 2 million Americans have advanced macular degeneration and another 8 million people are at risk.  The following are a list of systemic and environmental factors that contribute to the disease:
1.       Race – Macular degeneration is more prevalent among Caucasians.
2.       Family History
3.       Cigarette Smoking
4.       Cardiovascular Health – Hypertension, elevated cholesterol, and higher BMI increase risk
5.       Unhealthy Diet – Deficient in vitamins and antioxidants
6.       UV Exposure
 
What steps can be taken to help prevent the disease?
A variety of lifestyle habits can be implemented to help reduce your risk for macular degeneration.
1.        Don’t smoke
2.       Exercise regularly and maintain a healthy body weight and good cardiovascular health
3.       Eat foods rich in vitamins and antioxidants, specifically carotenoids
4.       Take a daily multivitamin (unless otherwise directed by your physician)
5.       Wear UV protective eyewear

What are carotenoids?
Carotenoids are naturally occurring pigments that are antioxidants and a source of Vitamin A.  Lutein and zeaxanthin are two carotenoids found in the macula.  They help prevent oxidation and damage to the retinal tissue caused by UV radiation.  Leafy greens, like kale and cooked spinach, are excellent sources of carotenoids.
 
What are the highlights of the AREDS2 study?
The goal of AREDS2 was to reevaluate the formulation of vitamins specifically designed for individuals with moderate macular degeneration.   The original AREDS study, conducted in 2001, found that high doses of beta-carotene along with vitamin C, vitamin E, zinc, and copper could reduce the progression of macular degeneration from moderate to advanced disease in 25% of patients.  Unfortunately, these doses of beta-carotene increased the risk of lung cancer for current and former smokers.  Furthermore, clinical studies have demonstrated that consumption of high doses of zinc increase risk for prostate cancer development twofold.
AREDS2 sought to evaluate whether beta-carotene could be substituted with lutein and zeaxanthin.  These carotenoids are not associated with the developments of cancer.  The study also investigated the necessity of high doses of zinc and the overall efficacy of omega-3 fatty acids.  The following provides a brief synopsis of the results:
  • Lutein and zeaxanthin ARE acceptable substitutes for beta-carotene and are slightly more effective in preventing progression to advanced stages of macular degeneration.
  • Zinc is a necessary component in vitamin formulations for macular degeneration.  The exact amount of zinc needed, however, is undetermined.   Lower doses of zinc may eventually be recommended to negate the potential for other adverse side effects.
  • Omega-3 fatty acids do not have an effect in the prevention of macular degeneration progression.  Many eye-care professionals, however, continue to recommend omega-3 supplementation because of the systemic health benefits.


If you have any questions about macular degeneration and your eyes, feel free to contact our doctors at alpinevision2020@gmail.com or ask at your next eye exam.




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