Following is a summary of a lecture presented at the annual meeting of the American Academy of Ophthalmology in Chicago in October 2005.
INFLAMMATION and AMD Paul Honan, M.D.
Age related macular degeneration (AMD) is a challenge in the practice of general ophthalmology. Patients are becoming more informed and expect answers.
Patients get medical information from the internet, radio and TV, magazines and newspapers, family and friends and physicians. Media coverage of medicine is considered as factual information. Ophthalmologists are expected to have current information concerning AMD.
Patients ask about Paul Harvey ads for eye vitamins for AMD, other ads for antioxidant combination supplements and nutritional information.
Having been in the practice of ophthalmology for several years I have had the opportunity to follow the visual acuities and observe the maculae of patients as they have aged. Several years ago most were not aware that 20/20 visual acuities in their 40’s and 50’s gradually faded to 20/25, 20/30 and 20/40 as they reach their late 50’s and 60’s. Eventually many developed drusen and macular pigment changes associated with AMD and visual acuity worsened. In some the visual acuity worsened without observable macular changes.
In recent years better-informed patients seem to be more aware of their changing visual acuities. They ask if they are developing AMD. They ask how to avoid AMD. It is no longer acceptable to indicate that the value of supplements and dietary modification is not really well established for prevention and treatment of AMD.
People want answers even if they are not definitive. Physicians have a responsibility to give the best advice we can while pointing out where the evidence is uncertain. What advice we can while pointing out where the evidence is uncertain. What advice should be provided about AMD? How early can AMD be diagnosed? Some children of parents with AMD become very anxious if their visual acuity decreases to less than 20/20.
Following is information from screens from a PowerPoint presentation on Inflammation and AMD.
Microvascular disease in addition to causing AMD may be associated with a range of vascular diseases such as coronary artery disease, heart failure, diabetes, and stroke. Persons with signs of retinopathy may require careful cardiovascular disease risk assessment and appropriate risk reduction therapy. (ARVO 2005)
Cardiovascular disease has been associated with an increase incidence of AMD in several studies. (AREDS, Beaver Dam)
The Blue Mountain study confirmed that cigarette smoking is a principal environmental risk factor for AMD.
Researchers are increasing recognizing the link between cardiovascular disease and inflammation and also AMD. (JAMA)
C-reactive protein (CRP), a systemic inflammation marker associated with an increased risk of cardiovascular disease also has been associated with AMD in a clinic-based case controlled study. (JAMA)
Higher levels of the systemic inflammation markers CRP and interleukin-6 (IL-6) are independently associated with progression of AMD. (Archives of Ophthalmology)
Persons who have higher blood levels of lutein/zeaxanthin; vitamin C, beta-carotene and who eat fish regularly have lower levels of C-reactive protein. (AREDS)
Eating fish rich in omega-3 fatty acids and taking antioxidant supplements may help prevent progression of AMD. (ARVO 2005)
Antioxidant combinations supplements have been shown to reduce the risk of development of wet AMD by 25%. (AREDS)
Persons with unilateral advanced AMD taking antioxidants studied in AREDS have reduced risk of developing advanced AMD in the other eye. (U Pittsburgh)
AREDS supplements reduced further AMD visual loss as long as acuity was at least 20/100 when starting the supplements. (U Pittsburgh)
Dietary omega-3 fatty acids may play a crucial role in AMD and are essential for both the structure of the eye and signaling pathways. (NEI)
AMD is half as likely to progress in those with highest consumption of fish rich in eicosapentaenoic acid (EPA) than in those with lowest fish consumption. (NEI)
Risk of development of AMD is 40% less in those who consumed fish rich in omega-3 fatty acids once a week. (Blue Mountain)
There is increased risk of AMD with low intake of omega-3 fats. (Blue Mountain Study)
Anti-inflammatory agents may have a role in preventing AMD. (Archives of Ophthalmology)
Wellness is usually considered as a state of health in which there is absence of manifest disease. Inflammation can exist silently for years before manifest disease develops. A new definition of wellness is the absence of inflammation. Markers recommended at the meeting of the American Academy of Anti-aging Medicine in Chicago September 2005 in addition to CRP and IL-6 were blood levels of insulin and the aracadonic acid/EPA ratio (AA/EPA).
What should be the advice to concerned patients? Patients in our office are advised that studies are not conclusive but tend to support the use of:
Omega-3 fatty acids in fish oil (2,5 gm EPA + DHA)
Eat fatty fish (salmon, sardines, etc.)
Dietary modification: (More veggies, berries, fruit and less sugars and grains)
Vitamin C 500 to 1000mg tid, vitamin E, Beta-carotene)
Ultraviolet protective eyewear when in the sun.
Clinical observations indicate that many (most) improve up to 4 lines on the Snellen chart in a time frame of a few months. Questionable improvement may be realized if starting visual acuity is over 20/60. It is not known if further decrease in visual acuity is being delayed. Some adult children of parents with extensive AMD have opted to adopt the above regimen as a measure of prevention. The new media has created an awareness also of the potential cardiovascular benefits of the above regimen.
Macular Degeneration
Age related macular degeneration is a condition in the retina of the eye that can affect vision severely. One third of people over age 65 cannot read or drive motor vehicles because of it. The gradual decrease in vision may start in the 50’ s.
The retina is the inside lining of the back of the eye that functions like the film in a camera. The macula is a pinpoint area in the center of the retina that provides sharp central vision (20/20).
The cause of macular degeneration and its prevention and treatment have been the subject of much research. There are two main types dry and wet. Ninety percent of cases are dry and 10% are wet. The wet causes usually develop in the dry type. The dry type develops very gradually usually over the period of years. The wet may develop suddenly with sudden blur with sudden hemorrhage under the retina. Sometimes a retinal specialist can remove the hemorrhage. There are some new injection type surgeries to treat the wet type. Some vision may be recovered.
The dry type has been the subject of research indicating that certain supplement and a diet rich in vegetables and fruit can slow down the degenerative process.
As in any disease condition prevention is of great importance. Following is a recent article that indicates that a diet regimen may be valuable in prevention.
Ocular Surgery News January 3, 2006
Study: Diet high in antioxidants may be “more important than supplements” for AMD
A diet including high levels of beta-carotene, vitamins C and E and zinc was associated with a substantially reduced risk of age-related macular degeneration in elderly people in a Dutch study published in the Journal of the American Medical Association.
“This study suggests that the risk of AMD can be modified by diet; in particular, by dietary vitamin E and zinc,” the study authors said in a press release from JAMA. “Based on this study, foods high in these nutrients appear to be more important than nutritional supplements.”
Redmer van Leeuwen, MD, PhD, and colleagues at Erasmus Medical Center in Rotterdam analyzed data from 4,170 people enrolled in the Rotterdam Eye Study. Participants were at least 55 years old at baseline (1990 to 1993) and were followed through 2004. Over the course of the study, 560 people (13.4%) were newly diagnosed with AMD, the majority of whom had early-stage AMD.
“A significant inverse association [in risk for AMD] was observed for intake of vitamin E, iron and zinc,” according to the press release from JAMA. An increase in intake was associated with a reduced risk of AMD of 8% for vitamin E and 9% for zinc. An above-median intake of beta-carotene, vitamins C and E and zinc, when compared with below-median intake of at least one of the nutrients, was associated with a 35% reduced risk of AMD. In people with below-median intakes of all nutrients, the risk of AMD increased by 20%.
The results suggest that a high intake of specific antioxidants from a regular diet may delay the onset of AMD, the study authors said.
Sources of Iodine: Foods that are high in iodine include iodized salt, seafood, saltwater fish, and kelp. It may also be found in asparagus, garlic, lima beans, mushrooms, sea salt, sesame seeds, soybeans, spinach, summer squash, Swiss chard, and turnip greens.
Sources of Vitamin K: Vitamin K is found in some foods, including asparagus, blackstrap molasses, broccoli, Brussels sprouts, cabbage, cauliflower, dark green leafy vegetables, egg yolks, liver oatmeal, oats, rye safflower oil, soybeans, green tea and wheat.
Sources of Zinc: Zinc is found in the following food sources: brewer’s yeast, egg yolks, fish, kelp, lamb, legumes, lima beans, liver, meats, mushrooms, pecans, oysters, poultry, pumpkin seeds, sardines, seafood, soy lecithin, soybeans, sunflower seeds, and whole grains.
Sources of Vitamin C: Vitamin C is found in berries, citrus fruits, and green vegetables. Good sources include asparagus, avocados, beet greens, broccoli, Brussels sprouts, cantaloupe, collards, dandelion greens, grapefruit, kale, lemons, mangos, mustard greens, onions, oranges, papayas, green peas, sweet peppers, persimmons, pineapple, radishes, rose hips, spinach, strawberries, Swiss chard, tomatoes, turnip greens and watercress.
Sources of Iron: Iron is found in eggs, fish, liver meat, poultry, green leafy vegetables, whole grains, and enriched breads and cereals. Other food sources include almonds, avocados, beets, blackstrap molasses, brewer’s yeast, dates kelp, kidney and lima beans, lentils, peaches, pears, dried prunes, pumpkins, raisins, rice and wheat bran, sesame seeds, soybeans, and watercress.
