Gene Therapy May Save Sight
New hope for macular degeneration patients
Macular degeneration is the number one cause of permanent vision loss in patients over 55. Now genetic analysis is helping to reduce the risk of vision loss by assisting doctors in identifying the risk of progression and the best treatment for that individual based on their individual DNA.
This is one of the first applications of gene-optimized preventative care in eye care available at the office level. If widely adopted, it has significant potential to reduce vision loss.
In standard age-related macular degeneration treatment, eye doctors try to predict who will progress to the advanced stage so treatment may be instituted in a timely manner. While we know factors such as advancing age, smoking, high blood pressure and other vascular diseases are associated with progression, there have been few solid ways to calculate a particular individual’s risk. Of all the risk factors, genetics play the most important role being the underlying cause in 86% of cases.
Now genetic testing can identify a person’s individual risk of progressing to advanced macular degeneration, and subsequent analysis can help determine which follow-up timeline and which supplement type will minimize risk for that particular patient.
We learned in the Age-Related Eye Disease Study (AREDS) that certain antioxidant vitamins and zinc will slow the risk of progression by about 25%; however, further genetic testing on study participants determined that in those with certain genetic profiles, the risk could be further reduced and in those with other genetic profiles, risks were actually increased by following the AREDS protocol. Thus, they concluded that one’s genetic makeup affects how he/she will respond to certain treatment.
The treatment protocol recommendations developed from subsequent genetic analysis of the 2002 AREDS patients now include antioxidants plus zinc (AREDS and AREDS2 formulae); antioxidants alone; and zinc alone versus the same AREDS formulae for all macular degeneration patients.
While this new technology offers doctors significant assistance in creating a care plan, multiple factors need to be considered for optimal health and results. Based on genetic assessment, up to 50% of patients should be taking high dose supplements other than those in the AREDs and AREDS2 formulae.
Let’s say, for example, your genetic assessment results indicate that you should avoid antioxidants as a treatment protocol. Does that mean you should avoid all supplements with antioxidants? Patients should continue to use a multivitamin as long as they don’t have high dose anti-oxidants (Lutein or Zeazanthin). If they follow these recommendations they can reduce the average 5-year progression rate to 8% (versus 29% for taking a placebo, 29% for the standard AREDS formulae and 38% for antioxidants only).
Vita Risk (supplement component) is included in the Macular Risk profile (15-gene profile) but can also be ordered as a stand-alone test. If you have already had genetic testing for macular degeneration, ask your doctor if the “Macular Risk” test was done. There are three different genetic companies providing testing. If so those results can be referenced to make treatment recommendations. If you have not had it done, and you are a Medicare or PPO patient with either macular degeneration or macular drusen, then the test is covered. If you have an HMO or are a private pay patient, you may have either of the genetic tests performed for a cash fee.
Dr. Evans is the founding owner of Evans Eye Care in Palm Desert and can be reached at (760) 674.8806 or online at www.evanseyecare.com.