Females under the age of 75 years whose blood levels of vitamin D are high appear to have a reduced risk of developing AMD (Age-Related Macular Degeneration), researchers from the University of Buffalo, New York, wrote in Archives of Ophthalmology.
Macular degeneration is when the patients start losing their central vision - objects directly in front of them are harder to see, making such tasks as reading, writing, recognizing faces and driving much more difficult. The macular, or macula lutea is an oval-shaped yellow spot close to the center of the retina, in the eye. Macular degeneration, caused by damage to the retina, mainly affects elderly individuals. It is the main cause of partial-blindness among patients over the age of 50 years. Even though central vision is affected, because the patient still has peripheral vision, other activities in daily life are usually still possible to do.
The authors wrote:
"Age-related macular degeneration (AMD), a chronic, late-onset disease that results in degeneration of the macula, is the leading cause of adult irreversible vision loss in developed countries. Age-related macular degeneration affects approximately 9 percent (8.5 million) of Americans aged 40 years and older."
Amy E. Millen, Ph.D., and team set out to find out whether serum 25(OH)D blood levels were linked to age-related macular degeneration risk. They gathered data on 1,313 females who had participated in the Carotenoids in Age-Related Eye Disease Study, part of the Women's Health Initiative Observational Study.
The authors wrote:
"Serum 25(OH)D is the preferred biomarker for vitamin D status, as it reflects vitamin D exposure from both oral sources and sunlight."
After making adjustments for several AMD risk factors, they could not identify any significant link between vitamin D levels and early or advanced AMD.
Among 968 females aged less than 75 years whose serum 25(OH)D was high, the risk of developing early AMD was significantly lower, the researchers observed. However, among the 319 older females with higher serum 25(OH)D, there was a very slight increase in AMD risk.
The women under 75 with the highest vitamin D levels were found to have a 59% lower risk of developing early AMD compared to those with the lowest levels.
The authors wrote that milk, fish, fortified margarine and fortified cereals were among the top food sources of vitamin D. They found no link between self-reported direct sunlight exposure and AMD risk.
Seniors whose diets are rich in omega 3 fatty acids have a significantly lower risk of developing AMD (age-related macular degeneration) compared to other people of the same age, scientists revealed in the journal Ophthalmology. Good sources of Omega 3s are cold water oily fish, such as sardines, anchovies, mackerel, herring and salmon, as well as several types of shellfish.
The researchers concluded:
"This is the second study to present an association between AMD status and 25(OH)D, and our data support the previous observation that vitamin D status may potentially protect against development of AMD. More studies are needed to verify this association prospectively as well as to better understand the potential interaction between vitamin D status and genetic and lifestyle factors with respect to risk of early AMD."
"Vitamin D Status and Early Age-Related Macular Degeneration in Postmenopausal Women"
Amy E. Millen, PhD; Rick Voland, PhD; Sherie A. Sondel, MS; Niyati Parekh, PhD; Ronald L. Horst, PhD; Robert B. Wallace, MD; Gregory S. Hageman, PhD; Rick Chappell, PhD; Barbara A. Blodi, MD; Michael L. Klein, MD; Karen M. Gehrs, MD; Gloria E. Sarto, MD, PhD; Julie A. Mares, PhD; for the CAREDS Study Group
Arch Ophthalmol. 2011;129(4):481-489. doi:10.1001/archophthalmol.2011.48
Research & Treatments
Choices Depend Upon Early Detection
> > > New infromation is marked with an asterisk * < < <
Depending upon the advancement of AMD and CNV various types of surgery and drug administrations are possible. Although there is no wonder cure for the disease, there are many fine ophthalmologic groups working on the causes and control of AMD. Research is the key to future AMD advancements. I shall try to keep this page up-to-date for you.
Smoking and AMD
A report in the Journal of the American Medical Association confirmed that cigarette smoking increases ones risk of developing AMD by 2.5 times. Unfortunately the increased risk persists even after 15 years of quitting. Along with all of the other health related ailments caused by smoking the message is even clearer . . . . BUTT OUT NOW !
Retinal or Macular Translocation *
Dr. David Wong an eye surgeon at the Royal Liverpool University Hospital in northwest England has received extensive press coverage about his recent surgical procedure on a 70 year of man in which he manipulated the retina by pulling an area of it to one side and tucking it under to provide a new undamaged retinal surface area over the fovia. Although this procedure is new, it does not halt the progression of the disease and is not a cure. The procedure is still under refinement in both Germany and the United States. Dr Eugene de Juan a professor at the Wilmer Eye Institute is also performing this experimental procedure.
Interferon Trials *
Interferon-alfa-2a is a very expensive drug with fairly harsh side effects that has been studied in many international centers. The drug affects the patterns and nature of capillary division when the capillaries are actively growing and dividing. A 45 center world-wide study reported that this avenue of research does not show much promise as a useful treatment for AMD. The latest concensus is that Interferon alfa-2A provides no benefits as a treatment for choroidal neovascularization secondary to ARMD and may be associated with poorer visual outcome at certain stages.
To be effective, cortisone has to be administered in sufficient quantity to affect the back of the eye and it has serious side effects if given in high doses. Recently methods of injecting cortisone directly into the eye have been developed and this is a significant breakthrough. Studies are still in progress but it looks very promising.
Wine Consumption and AMD*
There have been a few newsgroup postings concerning wine comsumption and the reduced risk of developing AMD. The results of a five year sturdy from the National Health Nutrition and Examination Survey (NHANES-1) indicated that 7% of those over age 65 will develop AMD if they do not consume 2-12 glasses of red or white wine per year. On the other hand, only 4% will develop the condition if they drink less than one glass of wine per month. Heart disease and AMD share many risk factors and aong them is the tendency of platelets to accumulate along blood vessel walls. Wine has high phenolic content and because phenols are antioxidants, they play a role in reducing platelet formation along blood vessel walls. Beer and liquor has less phenols than wine by the way. Caution is advised due to the other risks associated with alcohol comsumption, namely drug interactions and reduced motor skills often resulting in injury or accident.
This is the drug that made headlines 34 years ago when it was found to be cause of approximately 12,000 birth deformities around the world. But today, researchers at the Scheie Eye Institute in Philadelphia, the Massachusetts Eye and Ear Hospital in Boston and the Mt. Sinai Medical Campus in Cleveland are researching thalidomide drugs that are showing great promise in experimental settings and pilot trials. The drug has the ability to inhibit the formation of blood vessels (angiogenisis) which may make it useful for halting AMD vision loss.
Growth Hormone (GH) and Insulin-like Growth Factor (IGF-1)*
New research is underway by Dr. Lois E.H. Smith an assistant professor of ophthalmology at Harvard Medical School in Boston MA. Study findings suggest that inhibiting GH or IFG-IGF-1 or both may hold promise as a way to treat and control proliferative diabetic retinopathy, retinopathy of prematurity and age-related macular degeneration. Experimental evidence with mice look good although for we humans it is many years away from clinical practicality.
Shark Cartilage and Angiogenesis*
The use of shark cartilage for the treatment of cancer stems from the fact that it an anti-angiogenic substance (it inhibits the growth of new blood vessels). Excessive vascularization of the eye should respond to anti-angiogenic treatment mechanisms although no definitive research is available at this time concerning the use of shark cartilage.
Applicable only to wet type AMD with associated SRNV (Sub-Retinal Neo-Vascularization), specialized lasers are focused on the blood vessels growing beneath the retina and cause the vessels to burn and scar (cauterization), thus sealing off the flow of leaking blood. A badly damaged macula in the advance stages of AMD will not benefit from laser treatments.
Using a high-speed scanning pulsed laser to acquire rapid sequences of images of the blood vessels underlying the retina, doctors at the Glaser Murphy Retina Treatment Centre have developed a new technique of identifying individual feeder vessels which can then be accurately targeted for micro-laser coagulation. This proceedure results in higher prcision laser targeting treatments and reduces the amount of unnecessary damage to surrounding healthy retinal tissue.
Dye Assisted Photocoagulation
Indocyanine green dye is being used for dye assisted laser photocoagulation to offer a better guide for pinpointing offending neovascularization beneath the macula. The dye targets and sensitizes the vessels to help focus laser energy used in some types of eye surgery.
Intraocular Telescopic Lens*
In the realm of future bionics I read an article recently about a team of researchers who are experimenting with an intraocular implant of a lens and telescope combination. Their tests with cadaver eyes have shown some promise and the future for AMD sufferers may be in the form of a "inside-the-eye" telescopic lens. Research however far fetched may some day provide viable solutions, so don't laugh too hard, my friend.
New techniques for ultra fine submacular surgery are being developed by various institutions including the Eye Institute of West Florida and the Center for Macular Degeneration at the University Hospital - New Jersey Medical Clinic. Removal of tiny blood vessels requires unique approaches and new surgical instrumentation.
Photodynamic Therapy (PDT) *
A light activated drug is injected into the bloodstream which has the ability to concentrate in areas of neovascularization. A low-power non-thermal red laser is shined into the eye where it causes a degredation of the blood vessels involved in the neovascularization process (sort of like a dissolving reaction). Miravant in Santa Barbara,CA will start Phase 3 testing in November this year with its drug PURLYTIN (SnET2, tin ethyl etiopurpurin). QLT Phototherapeutics in British Columbia, Canada with its partner Ciba Vision, Atlanta, GA are presently in Phase 3 trials with its drug VERTEPORFIN (BPD, a liposomal benzoporphyrin derivative). Unlike confluent laser photocoagulation, which causes concurrent damage to other healthy areas of the retina, photodynamic therapy is very selective and its low-power minimizes the risk to surrounding healthy macular tissue.
Matrix Metalloprotease Inhibitor Designer Drug*
Agouron Pharmaceuticals Inc, in La Jolla, CA is investigating the use of a drug called AG3340 as a therapy for AMD. The synthesized drug was designed to fit into the receptor sites on the surface of cell membranes where the biochemical reaction allowing the development of the blood vessels occurs, thus inhibiting a family of enzymes known as matrix metalloproteases. In other words, it stops the development of new blood vessels. Trials are presently underway.
Retinal Pigment Removal
Monkey studies have shown promise for a technique which involves removing damaged retinal pigment epitherial (RPE) cells. The natural regeneration process of the host body re-grows normal cells as part of the healing process. Further studies are underway.
Microcurrent Stimulation Therapy*
Golfer Sam Snead experienced significant improvement in one of his eyes after treatments by one of the research partners of the Macular Degeneration Foundation. Currently undergoing clinical analysis, microcurrent stimulation therapy seems to show some promise, especially those with the DRY type of ARMD. Further information is available from Dr. Damon P. Millar II who specializes in this treatment.
Argon Laser Heat Treatment
The green light of an argon laser when used at low energy levels can be used to heat rather than vaporize tissues, sort of like a welder. The National Eye Institute hopes this treatment will offer 50% or better chance of slowing or stopping severe vision loss from AMD.
RheoTherapy Blood Filtration*
The technology employs a series of therapeutic apheresis (blood filtration and purification) procedures which remove toxic waste material (such as macro-proteins, lipids, cholesterol, and others) that accumulate over time in the blood and certain tissues, which are believed to cause the symptoms of many common eye diseases including AMD. The company, Occulogix Corp, has stated that while the results are promising, they are from a pilot study and until a definitive trial has been established with results documented, they cannot conclusively state whether the treatment is safe and/or effective. From 4 to 10 treatments at about $2,000 per session are required.
Increased consumption of dark green, leafy vegetables (such as spinach and collard greens) seems to indicate that AMD can be delayed many years. LUTEIN and ZEAXANTHIN carotenoids which are primarily found in dark green leafy vegetables are among the best risk reducing naturally occurring substances for AMD. Kale, collard greens, and spinach are the best known natural sources of these carotenoids.
Confocal Laser Ophthalmoscope*
A German team of doctors has reported their clinical experience with a new type of ophthalmoscope which simultaneously captures fluoresein and indocyanine-green angiographic images through the use of a dual dye injection. The method is superior to individual angiography since it produces simultaneous digital image frames, requires only one injection and is not associated with additional side effects.
Vitamins, Minerals and Anti-Oxidants
There is evidence that certain dietary components known as antioxidants can help prevent macular degeneration. Many doctors believe that Vitamins A, C and E and dietary carotenoids, are essential for ocular wellness. These nutrients can inhibit oxidative reactions. Some minerals, such as zinc, copper and selenium, may also be involved. To learn more about these supplements visit Preventions Magazines 'Healthy Ideas'. It should be noted that the usage of vitamin and mineral supplements should be started only under the supervision of a qualified physician.
Although there is no proof that zinc taken orally has any significant effect on AMD it is claimed to have stabilized some cases of AMD. The inconclusive results are diminished by the fact that too much zinc is bad for your overall health. Limits on the amount of zinc in vitamin supplements is now in place. The major dietary source of zinc are shellfish (especially oysters), meat, liver, poultry, eggs, and dairy products.
Eye Disease linked to Atherosclerosis?*
Researchers at the Erasmus University Medical School in Rotterdam, The Netherlands produced a paper in 1995, about the link between AMD and atherosclerosis. Recently a study at the University of Wisconsin at Madison, WI failed to find a strong relationship between the two diseases. ( Editors Note: Here again we find that more research and long-term analysis is needed.
Sunglasses and Ultraviolet Filters
Studies and reports are surfacing that indicate a link between certain types of light energy and the onset of AMD. More UV rays from sunlight reach the retina in blue-eyed patients, probably because of the lower pigment density in the eye. NoIR Medical Technologies manufactures and sells sunglasses specially designed to aid people with Macular Degeneration.
At the Medical College of Georgia and UMDNJ - University Hospital, the same types of x-rays used to destroy tumors in the eye are now being aimed at the back of the eye to halt the abnormal proliferation of blood vessels behind the retina. Recent pilot studies reported at a Radiological Society of North America meeting indicated that radiation treatments may play a vital role in treating sub-retinal neovascularization (SRNV). At the Cedars-Sinai Comprehensive Cancer Center in Los Angeles, California a pilot study is underway using low dose radiation. There is also a new technique called stereotactic radiotherapy that uses 3D images to direct radiation to specific blood vessels to stop bleeding.
Strontium 90 Radiation *
Dr. Luther W. Brady at the Allegheny University of Health Sciences, Philadelphia, PA has demonstrated the successful use of an applicator tipped with strontium 90. The emitted beta radiation penetrates only about 1mm of tissue, so the applicator is inserted directly (under anesthesia) into the effected eye through a small lateral incision. Further results are to be presented later this year at a meeting of the American Radium Society in New York.
Proton Beam Radiation*
In a protocol similar to X-ray radiation, Dr. Leslie T. Yonemoto and colleagues at Loma Linda University Medical Center, Loma Linda, CA. are using a proton beam as the radiation source. With a mean follow-up of 11.6 months, 58% of the test subjects demonstrated improved or stable visual acuity.
Foetal Tissue Implant
A very high risk and still controversial procedure which involves implanting a quantity of retinal tissue from a second trimester aborted foetus into a degenerated retina. If the cells are not rejected by the host patient and begin to differentiate into the correct retinal cells types, it is hoped that vision improvement will result in a matter of months. In January 1997 the first publicized operation in the United States was performed at the University of Chicago Medical Center on an 80 year old patient with macular degeneration. Read the whole article entitled Heroes of Medicine. Previous operations in Sweden in 1994 met with very limited success.
Viagra (Sildenafil) Warning*
Doctors at the American Academy of Ophthalmology (AAO) have warned users of the newly-approved anti-impotence drug, Viagra and its potential side effects on vision. There are no long-term studies available yet concerning the use of viagra for persons with retinal eye conditions such as AMD and retinitis pigmentosa, so they advise staying within the recommended FDA dose level of 50 mg.
The Genetic Link
At Boston's Massachusetts Eye & Ear Infirmary and at the Duke University Medical Center in Durham, NC, researchers are trying to isolate the gene that triggers macular degeneration. They hope to discover how to identify people at risk of developing AMD. Volunteers for gene research should visit MEEI for more information. Early detection means better treatment because once the damage occurs, central vision usually cannot be restored.
Stargardt disease, clinically known as fundus flavimaculatus is the most common inherited form of macular degeneration and accounts for 7 percent of all inherited retinal diseases. It shows up in juveniles between 6 and 12 years of age and causes the same rapid and severe central vision loss as in the elderly. Researchers have now discovered mutations in the ABCR gene, which cause Stargardt disease, and may be close to mapping other genes responsible for retinal degeneration. Other rare forms of AMD also caused by mutation in a gene are Best's disease, Sorsby's disease, and the cblC type of cobalamin deficieny.