Study suggests link between regular aspirin use, increased risk of age-related macular degeneration

Regular aspirin use appears to be associated with an increased risk of neovascular age-related macular degeneration (AMD), which is a leading cause of blindness in older people, and it appears to be independent of a history of cardiovascular disease and smoking, according to a report published Online First by JAMA Internal Medicine.

16 feb 2013--Aspirin is one of the most widely used medications in the world and is commonly used in the prevention of cardiovascular disease, such as myocardial infarction (heart attack) and ischemic stroke. While a recent study suggested that regular aspirin use was associated with AMD, particularly the more visually devastating neovascular (wet) form, other studies have reported inconsistent findings. Smoking is also a preventable risk factor for AMD, the authors write in the study background.

Gerald Liew, Ph.D., of the University of Sydney, Australia, and colleagues examined whether regular aspirin use (defined as once or more per week in the past year) was associated with a higher risk of developing AMD by conducting a prospective analysis of data from an Australian study that included four examinations during a 15-year period. Of 2,389 participants, 257 individuals (10.8 percent) were regular aspirin users.

After the 15-year follow-up, 63 individuals (24.5 percent) developed incident neovascular AMD, according to the results.

"The cumulative incidence of neovascular AMD among nonregular aspirin users was 0.8 percent at five years, 1.6 percent at 10 years, and 3.7 percent at 15 years; among regular aspirin users, the cumulative incidence was 1.9 percent at five years, 7 percent at 10 years and 9.3 percent at 15 years, respectively," the authors note. "Regular aspirin use was significantly associated with an increased incidence of neovascular AMD."

The authors note that any decision concerning whether to stop aspirin therapy is "complex and needs to be individualized."

"Currently, there is insufficient evidence to recommend changing clinical practice, except perhaps in patients with strong risk factors for neovascular AMD (e.g., existing late AMD in the fellow eye) in whom it may be appropriate to raise the potentially small risk of incident neovascular AMD with long-term aspirin therapy," the authors conclude.

In an invited commentary, Sanjay Kaul, M.D., and George A. Diamond, M.D., of Cedars-Sinai Medical Center, Los Angeles, write: "This study has important strengths and limitations. It provides evidence from the largest prospective cohort with more than five years of longitudinal evaluation reported to date using objective and standardized ascertainment of AMD."

"The key limitation is the nonrandomized design of the study with its potential for residual (unmeasured or unobserved) confounding that cannot be mitigated by multivariate logistic regression or propensity score analysis," the authors continue.

"From a purely science-of-medicine perspective, the strength of evidence is not sufficiently robust to be clinically directive. These findings are, at best, hypothesis-generating that should await validation in prospective randomized studies before guiding clinical practice or patient behavior," the authors conclude. "However, from an art-of-medicine perspective, based on the limited amount of available evidence, there are some courses of action available to the thoughtful clinician. In the absence of definitive evidence regarding whether limiting aspirin exposure mitigates AMD risk, one obvious course of action is to maintain the status quo."

More information: JAMA Intern Med. Published online January 21, 2013. doi:10.1001/jamainternmed.2013.1583 
JAMA Intern Med. Published online January 21, 2013. doi:10.1001/jamainternmed.2013.2530

Provided by JAMA and Archives Journals

Vitamin D levels associated with age-related macular degeneration

Women under the age of 75 with high vitamin D status were less likely to have early age-related macular degeneration (AMD), the leading cause of irreversible vision loss in adults, a University at Buffalo study has shown. The disease affects approximately 9 percent of Americans aged 40 and older.

The paper is published in the April issue of "Archives of Ophthalmology," one of the JAMA/Archives journals.

13 april 2011--Vitamin D status was assessed using the blood measure of 25-hydroxyvitamin D or 25 (OH) D. The 25 (OH) D level is generally considered the means by which nutritional vitamin D status is defined.

"In women younger than 75, those who had 25-hydroxyvitamin D concentrations lower than 38 nanomoles per liter were more likely to have age-related macular degeneration than women with concentrations greater than 38 nanomoles per liter," says Amy E. Millen, PhD, assistant professor in the UB School of Public Health and Health Professions and lead author. "Blood concentrations above 38 nanomoles per liter were associated with at least a 44 percent decreased odds of having AMD."

She notes that the Institute of Medicine considers an adult with a blood 25 hydroxyvitamin D concentration of lower than 30 nanomoles per liter to be at increased risk of vitamin D deficiency and a person with a concentration of less than 50 nanomoles per liter to be at increased risk for vitamin D inadequacy.

Millen's "Carotenoids in Age-Related Eye Disease Study (CAREDS)" involved data from 1,313 women. The purpose of the study was to investigate if serum 25 hydroxyvitamin D levels in the blood, the preferred biomarker for vitamin D, were associated with early age-related macular degeneration. CAREDS is an ancillary study within the Women's Health Initiative (WHI) Observational Study, which was conducted at WHI clinic centers in Oregon, Iowa and Wisconsin. UB is a major participating center in the WHI.

"The take- home message from this study is that having very low vitamin D status (25-hydroxyvitamin D blood concentrations lower than 38 nanomoles per liter) may be associated with increasing your odds of developing age-related macular degeneration," says Millen. "But based on these study findings, being at a higher vitamin D level than 38 nanomoles per liter does not appear to be more protective," she cautions.

Vitamin D status may be increased by spending moderate amounts of time outside, and eating foods rich in vitamin D, such as fatty fish from cold waters, and foods fortified with vitamin D, such as milk and fortified cereal, or by taking supplements.

"This is a promising study, but more still needs to be done," says Millen. "We still don't understand all of the effects of Vitamin D on health."

Provided by University at Buffalo

Omega-3s in fish, seafood may protect seniors' eyes; a new test may catch glaucoma early

Seniors interested in lifestyle choices that help protect vision will be encouraged by a Johns Hopkins School of Medicine study, and people concerned about glaucoma can take heart from work on early detection by the University of Miami Miller School of Medicine. Both studies are published in the December issue of Ophthalmology, the journal of the American Academy of Ophthalmology.

New Evidence for Eye-Protective Effects of Omega-3-Rich Fish, Shellfish

05 dec 2010--Researchers at Wilmer Eye Institute, Johns Hopkins School of Medicine, wanted to know how the risk of age-related macular degeneration (AMD) would be affected in a population of older people who regularly ate fish and seafood, since some varieties are good sources of omega-3 fatty acids. A diet rich in omega-3s probably protects against advanced AMD, the leading cause of blindness in whites in the United States, according to the Age-Related Eye Disease Study (AREDS) and other recent studies. High concentrations of omega-3s have been found in the eye's retina, and evidence is mounting that the nutrient may be essential to eye health. The new research, led by Sheila K. West, PhD, was part of the Salisbury Eye Evaluation (SEE) study.

Food intake information with details on fish and shellfish consumed was collected over one year using a validated questionnaire for 2,391 participants aged 65 to 84 years who lived along Maryland's Eastern Shore. After dietary assessment was complete, participants were evaluated for AMD. Those with no AMD were classified as controls (1,942 persons), 227 had early AMD, 153 had intermediate-stage disease, and 68 had advanced AMD. In the advanced AMD group, the macular area of the retina exhibited either neovascularization (abnormal blood vessel growth and bleeding) or a condition called geographic atrophy. Both conditions can result in blindness or severe vision loss.

"Our study corroborates earlier findings that eating omega-3-rich fish and shellfish may protect against advanced AMD." Dr. West said. "While participants in all groups, including controls, averaged at least one serving of fish or shellfish per week, those who had advanced AMD were significantly less likely to consume high omega-3 fish and seafood," she said.

The study also looked at whether dietary zinc from crab and oyster consumption impacted advanced AMD risk, but no significant relationship was found. Zinc is also considered protective against AMD and is included in an AMD-vitamin/nutrient supplement developed from the AREDS study. Dr. West speculated that her study found no effect because the levels of zinc obtained from seafood/fish were low compared to supplement levels.

A side note: fish and shellfish were part of the normal diet of the study population, rather than added with the intention of improving health. The links between fish consumption, omega-3s and healthy lifestyles were not widely known in the early 1990s when the dietary survey was conducted. In fact, some of the study participants who consumed the most seafood were also smokers and/or overweight, two factors usually associated with AMD and other health risks.

Retinal Nerve Function May be Key to Early Glaucoma Detection

Catching glaucoma as early as possible–before it destroys the optic nerve–is vital to preventing vision loss. Now a research team at Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, has shown that a test that measures the functionality of the eye's retinal nerve cells may be a key to early detection. Eventually, the test may also help evaluate how well glaucoma treatments are working.

The research, led by Mitra Sehi, PhD, and David Greenfield, MD, was based on the knowledge that retinal ganglion cells (RGCs) become dysfunctional as glaucoma progresses and that such changes can be measured using the pattern electroretinogram optimized for glaucoma screening (PERGLA). PERGLA measures the electrical activity of a patient's retina as he or she views an alternating pattern of black and white lines. (The retinal area in the back of the eye receives images and transmits them to the optic nerve.) Other studies had shown that abnormal changes in RGCs begin early in the glaucoma process, so PERGLA is potentially valuable as a non-invasive detection tool.

The Bascom Palmer study included 47 patients (47 eyes) in whom intraocular pressure (IOP) could not be controlled with medication and who therefore had surgery to prevent optic nerve damage. All patients had two PERGLA evaluations (as well as complete ocular exams, optic nerve assessment, and blood pressure measurement), one before surgery and one at three months post surgery. IOP and PERGLA measurements of the patients' fellow, non-glaucomatous, non-treated eyes were stable before and after surgeries. The surgeries improved fluid drainage in the eyes to reduce IOP; 34 eyes had trabeculectomy and 13 had glaucoma drainage implants.

PERGLA results showed that RGC dysfunction was reversed and IOP was reduced in all patients following surgery. The patients' central visual field tests improved, as well. Dr. Sehi says these results should be interpreted cautiously until confirmed by larger studies. She calls for longitudinal studies to clarify the relationship between reduced IOP and increased RGC response and to further investigate PERGLA assessment of RGC dysfunction as a biomarker for glaucoma.

Provided by American Academy of Ophthalmology

Can diet slow sight loss in the elderly?

16 june 2009--“Eating fish twice a week 'can help prevent eye disease',” The Daily Telegraph has reported. It said a study has found that omega-3 fatty acids, found in oily fish such as salmon and tuna, could help prevent age-related macular degeneration (AMD), the main cause of blindness in elderly people.

The study asked around 3,000 people with various stages of AMD about their diet and followed them up over time to see whether their AMD progressed. Half the participants were also given a daily supplement, containing antioxidants such as vitamins C and E and beta-carotene. The researchers found that taking the supplements together with a diet high in fatty acids “appeared to be counterproductive”, as the combination had less effect than a diet high in fatty acids but without supplements. The study also found that the risk of the disease progressing to an advanced stage might be lowered by eating foods with a low glycaemic index (GI). Low GI foods release their sugars into the blood more slowly than foods with a high GI.

The complex results from this study suggest that a diet rich in the DHA (docosahexaenoic acid) form of omega-3 may reduce the progression of early stage AMD in people not taking certain dietary supplements. Also, a low GI diet rich in omega-3 may reduce the risk of progression to advanced AMD. It should be noted that the results of this research may have been affected by factors other than the dietary ones investigated and require careful interpretation. In general, eating a healthy, balanced diet, including omega-3 fatty acids and low GI foods, may have various health benefits.

Where did the story come from?

This research was conducted by Dr C-J Chiu and colleagues from Tufts University, the University of Wisconsin School of Medicine and Public Health and the EMMES Corporation. The study was funded by the US Department of Agriculture, National Institutes of Health, Johnson & Johnson Focused Giving Program, American Health Assistance Foundation and the Ross Aging Initiative. The study was published in the peer-reviewed British Journal of Ophthalmology.

What kind of scientific study was this?

This study looked at whether the risk of developing age-related eye disease, in particular age-related macular degeneration (AMD), is affected by eating particular diets and taking certain dietary supplements. AMD is a major cause of blindness and results from deterioration of the macula, an area near the centre of the retina responsible for the central field of vision.

Researchers used data collected from people enrolled in a randomised controlled trial called the Age-Related Eye Disease Study (AREDS). The authors of this current paper reported that the AREDS trial had found that “people at risk of developing advanced AMD would benefit by taking high-dose antioxidants (vitamin C, vitamin E, beta-carotene) plus zinc oxide”.

Other studies have suggested that individuals may be protected from AMD by certain nutrients found in the diet (lutein, zeaxanthin and certain omega-3 fatty acids) and by eating a low GI diet. The GI of a food is an indicator of how fast the carbohydrates it contains will cause an increase in blood sugar levels. A high GI indicates a fast release and a low GI indicates a slow release. In the current study, the researchers wanted to look at whether supplement intake and diet might interact with each other and affect the risk of AMD progression.

In the AREDS trial, 3,640 participants were randomly assigned to receive one of four different daily supplement tablets. These were: a placebo, antioxidants (500mg vitamin C, 400IU vitamin E and 15mg beta-carotene), zinc (80mg as zinc oxide) with copper (2mg as cupric oxide), or antioxidants plus zinc.

At the start of the study, participants filled in questionnaires about their characteristics and provided information about their diets in a food frequency questionnaire. They also had a physical and eye examination, which included photographs of the macula. In particular, these photographs looked for the accumulation of deposits of material in the macula, called drusen. Although most people develop a few small drusen as they age, more and larger drusen in the macula are an early sign of AMD.

Macular photographs were repeated after two years and then every year until the end of the eight-year follow-up. Eyes were graded into five groups according to the level of signs of AMD present. Eyes were considered to have either early (groups 1 to 3) or advanced (groups 4 and 5) AMD. Over the follow-up period, the researchers noted when an eye first progressed to a higher AMD group.

For the current study, data on 2,924 participants (80% of those randomised) and 5,146 eyes was available for analysis. This excluded people with diabetes at the start of the study, those whose food questionnaires did not describe feasible energy intakes, those lost to follow-up or with missing data, and eyes with advanced AMD at the start of the study.

The researchers looked at how dietary factors affected AMD progression time. All nutrient variables were adjusted based on the individual’s total energy intake. The 25% of participants with the lowest intake of the DHA (docosahexaenoic acid) or EPA (eicosapentaenoic acid) forms of omega-3 fatty acid were compared with participants with higher intakes of these nutrients.

The researchers then carried out analyses to look at whether the supplements an individual was taking as part of the test affected these outcomes.

What were the results of the study?

Progression of early AMD

The researchers found that, overall, progression of early AMD was not significantly affected by dietary GI, consumption of beta-carotene or consumption of the DHA or EPA forms of omega-3 fatty acids.

However, the effect of dietary DHA on progression of early AMD was found to vary depending on what supplements participants were taking. Looking at the groups taking different supplements and placebo separately, the researchers found that:

• Consuming higher levels of DHA was associated with a reduced risk of progression of early AMD in people taking placebo supplements.
• There was no significant effect of DHA on progression of early AMD when participants consumed higher levels of DHA and used the supplements containing antioxidants or zinc or both.

Progression to advanced AMD

Having a low GI diet reduced the risk of progressing to advanced AMD. This protection occurred regardless of what supplements were being taken, but the level of protection varied slightly between the different supplement groups. The low GI diet and supplementation appeared to boost each other’s effects.

The researchers found that consuming the highest levels of DHA (64mg a day or more) and EPA (42.3mg a day or more) reduced the risk of progressing to advanced AMD. The quarter of participants with the highest consumption of DHA or EPA reduced their risk of progressing to advanced AMD by about 25% compared with the quarter of participants with the lowest consumption of these fatty acids (less than 26mg a day DHA or less than 12.7mg a day EPA). This reduction was not affected by the supplements the person was taking.

The researchers also found that:

• Having a low GI diet and high intake of omega-3 fatty acids (DHA or EPA) appeared to reduce the risk of progressing to advanced AMD more than any of these dietary factors alone.
• There was a trend towards increased risk of progressing to advanced AMD with higher intake of beta-carotene, but this trend did not reach statistical significance.
• There was no significant effect of dietary vitamin C, vitamin E, zinc or lutein/zeaxanthin on the risk of progressing to advanced AMD.

What interpretations did the researchers draw from these results?

The researchers concluded that there was an association between eating a diet high in DHA omega-3 fatty acid and a slower progression of early AMD.

Eating a diet with lower GI and higher intakes of DHA and EPA was associated with a reduced progression to advanced AMD.

These results show that a complex interaction between diet and supplements is involved in the progression of AMD. The interaction of diet and supplements appeared to be of benefit in some cases but appeared to counteract each other’s benefits in some cases.

Developing specific diet and supplement guidance for those with AMD requires further research into this interaction. Ideally, people should aim to eat a healthy diet, including omega-3 fatty acids and low GI foods, as it is likely to bring a range of health benefits.

There are some further important points to note when interpreting this study:

• People were randomly assigned to which supplement they would receive in the AREDS trial but could not be randomly assigned to their diet. This means that when comparing groups with different diets, the analysis may be affected by factors other than those assessed and that are not balanced between the groups (confounders). These may affect the likelihood of AMD worsening.
• The study analysed each eye separately. The fact that some participants contributed more than one eye to the analyses may have affected results.
• Diet was only assessed at the start of the study and participants’ diets may have changed over the seven-year follow-up.
• Although the study reported using a food frequency questionnaire that had been tested and shown to be a valid way of measuring intake, there may still have been some inaccuracies in people’s recall of what they ate.
• The majority (97%) of participants in the test were white, which means results may not be applicable to other ethnic groups.
• The authors note that because of the risk of lung cancer with taking beta-carotene, the AREDS supplement is not recommended for smokers.
• The researchers carried out a large number of statistical tests, which can lead to finding significant results by chance. The results should be interpreted cautiously.
• The study did not report the number of people or eyes with AMD progression in each group. This makes it difficult to determine the importance of the reported changes in risk. Also, the authors did not report exactly how many people fell into each of the groups compared. If very few people fell into some of the groups, this would reduce the reliability of results.

Links to the headlines

Oily fish 'can halt eye disease'. BBC News, June 9 2009

Eating fish twice a week 'can help prevent eye disease'. Daily Telegraph, June 9 2009

Links to the science

Chiu CJ, Klein R, Milton RC et al. Does eating particular diets alter the risk of age-related macular degeneration in users of the Age-Related Eye Disease Study supplements? Br J Ophthalmol, June 9 2009 (advanced online publication)

Diet May Protect Against Age-Related Macular Degeneration

The disease may share risk factors with cognitive impairment, one study suggests

18 may 2009-- Dietary intake may have an influence over the risk of developing age-related macular degeneration (AMD), according to two studies published in the May issue of the Archives of Ophthalmology, while a third study in the same issue indicates that cognitive impairment may share common risk factors with the eye condition.

Michelle L. Baker, M.D., of the University of Melbourne in Australia, and colleagues conducted a study of 2,088 patients aged 69 to 97 years and found that those with the lowest cognitive function test scores were the most likely to have early AMD compared to those with the highest test scores.

Jennifer S. L. Tan and colleagues at the University of Sydney in Australia conducted a study of 3,654 elderly Australians and found that among the 2,454 subjects examined five and/or 10 years later, eating one weekly serving of fish was associated with reduced risk of early AMD, as was consumption of one to two weekly servings of nuts. Elaine W. T. Chong, M.D., of the University of Melbourne in Australia, and colleagues found that in a study of 6,734 participants aged 58 to 69 years, dietary fat consumption may have affected the odds of developing the eye disease.

"Higher trans-unsaturated fat intake was associated with an increased prevalence of late AMD," Chong and colleagues write. "A diet low in trans-unsaturated fat and rich in omega-3 fatty acids and olive oil may reduce the risk of AMD."

Abstract - Baker
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Abstract - Tan
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Abstract - Chong
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Eye Disease, Cognitive Decline Linked in Study

16 may 2009-- Seniors who perform poorly on tests of language, memory and concentration are more likely to be suffering from the early stages of age-related macular degeneration, a major cause of vision loss, a new study suggests.

The finding stems from a look at the association between cognitive function decline and the onset of age-related macular degeneration (AMD) among approximately 2,000 Australian seniors between the ages of 69 and 97.

"We found that those who have memory impairment were more likely to have early stages of macular degeneration independent of the effects of age, education and vascular risk factors," said study co-author Dr. Tien Yin Wong, a professor in the department of ophthalmology within the Centre for Eye Research Australia at the University of Melbourne.

Wong and his colleagues published the findings in the May issue of the Archives of Ophthalmology.

Age-related macular degeneration is the leading cause of vision loss among the elderly. The researchers note that prior research has suggested that Alzheimer's disease and AMD share similar developmental pathways in terms of protein build-up and brain and eye changes.

The authors' current observations are drawn from an analysis of retinal photographs taken of study participants (more than 80 percent white and all enrolled in a larger cardiovascular health study), from which a diagnosis of early-stage AMD was made.

Those diagnoses were lined up against results of cognitive function and neuropsychological tests designed to assess each subject's abilities in terms of concentration, language, memory and orientation skills. Most were also tested for dementia and cardiovascular risk factors.

The researchers determined that nearly 16 percent of the participants had early AMD, while 135 and 86 patients were diagnosed with dementia or Alzheimer's disease, respectively.

Having dementia and/or Alzheimer's was not linked to an increased likelihood for early AMD. However, the authors found that an AMD diagnosis was associated with having poorer scores on cognitive testing -- a trend deemed small but "significant."

"Our study suggests that there may be common links in the cause and risk factors for both conditions," Wong said. "They further raise the possibility that preventive and treatment strategies targeted at one condition may be useful for another." They did not suggest that having AMD causes dementia.

Dr. Demetrios Vavvas, a specialist in AMD at the Massachusetts Eye and Ear Infirmary in Boston, agreed that "there's probably something common between the two problems."

"As a retinal physician I'm already alert that these people are older, and they might have cognitive decline," he noted. "So certainly there may be a common pathogenesis between these two diseases."

"To say there is a mild correlation between these two diseases is along expected lines from what we know from previous studies," said Vavvas. "But I don't think this changes my day-to-day clinical approach to our patients."

The same issue of the journal included two additional Australian studies -- one from the University of Sydney and the other from the Centre for Eye Research -- that indicate that AMD risk can be reduced by avoiding trans fats and by regularly consuming fish, nuts, olive oil and other foods containing omega-3 fatty acids.

Developments in age-related macular degeneration : Diagnosis and treatment

Steven R. Kaufman

15 mar 2009--Age-related macular degeneration (ARMD) is the leading cause of legal blindness of Americans over age 65 years. Severe loss of vision is usually due to exudative ARMD, of which there are about 200,000 new cases in the United States annually. Until recently, only a small fraction of patients benefited from treatment, but advances in the early diagnosis of the disease and major developments in therapy have substantially improved the prognosis of patients with ARMD. Because visual loss substantially reduces quality of life, effective management of ARMD will have increasing public health importance as the population ages. The American Academy of Ophthalmology recommends that people over age 65 years should have a comprehensive eye examination every 1 to 2 years to check for cataracts, macular degeneration, glaucoma, and other conditions. Those who complain of difficulty reading, driving at night, or adapting from sunlight to indoor lighting might have macular degeneration.

Kaufman SR. Developments in age-related macular degeneration: Diagnosis and treatment. Geriatrics. 2009;64(3):16-19.

Sunlight exposure plus low antioxidant levels may place older adults at risk for eye disease

15 oct 2008--A European study suggests that the combination of low plasma levels of antioxidants and blue light exposure from the sun is associated with certain forms of the eye disease age-related macular degeneration (AMD), according to a report in the October issue of Archives of Ophthalmology, one of the JAMA/Archives journals.
"The retina is vulnerable to the damaging effects of light," the authors write as background information in the article. "While wavelengths in the UV radiation range are largely absorbed by the cornea and lens, the retina is exposed to visible light, including blue light." Animal and laboratory studies suggest blue light may damage the retina and contribute to the development of AMD, which occurs when the area of the retina (macula) responsible for sharp vision deteriorates.
Antioxidant enzymes—including vitamins C and E, the carotenoids (lutein and zeaxanthin) and zinc—may protect against the harmful effects of blue light on the retina. Astrid E. Fletcher, Ph.D., of the London School of Hygiene & Tropical Medicine, and colleagues measured levels of these nutrients in the blood of 4,753 older adults (average age 73.2) who were part of the European Eye Study. Participants also were interviewed about their lifetime sunlight exposure and had photographs taken of their retinas to detect AMD.
Of the 4,400 participants with complete information available, 2,117 did not have AMD, 101 had neovascular (advanced, involving the formation of new blood vessels) AMD and 2,182 had early-stage AMD. Overall, there was no association between blue light exposure and neovascular or early AMD. However, blue light exposure was associated with neovascular AMD in the one-fourth of individuals with lowest antioxidant levels. "In particular, the combination of blue light exposure in the presence of low levels of zeaxanthin, alpha-tocopherol [vitamin E] and vitamin C was associated with a nearly four-fold odds ratio of neovascular AMD," the authors write.
Key recommendations from the results include ensuring the intake of key antioxidants, which can be accomplished by consuming recommended dietary intake levels of vitamin C and zinc and increasing consumption of carotenoid-rich fruits and vegetables, the authors note. In addition, individuals should take steps to reduce the exposure of the retina to blue light, such as wearing broad-brimmed hats and sunglasses when outdoors.
"In the absence of cost-effective screening methods to identify people in the population with early AMD, we suggest that recommendations on ocular protection and diet target the general population, especially middle-aged people," they conclude.

Genetic finding implicates innate immune system in major cause of blindness

11 oct 2008--Scientists have identified one of the genes implicated in age-related macular degeneration, the most common cause of blindness in developed countries.
The research, published online today in the Lancet, adds to the growing understanding of the genetics of age-related macular degeneration (AMD), which the researchers believe should ultimately lead to novel treatments for the disease.
Almost two-thirds of people aged 80 years or older are affected by AMD to some degree, with more than one in ten left blind by the disease. In the UK, the annual economic burden from the disease has been estimated to be as high as £80 million, a figure set to increase as our ageing population expands. The total yearly costs of health-care usage are seven-times higher for patients with AMD than for those unaffected.
Researchers have previously identified a number of other genes or genetic loci (regions of the genome) which affect a person's susceptibility to the disease. Now, in research part-funded by the Wellcome Trust, researchers at the University of Southampton have shown that a particular variant of the gene SERPING1, carried by just under a quarter of the population, appears to offer protection against the disease.
The University of Southampton team and colleagues from the University of Iowa found evidence of proteins expressed by SERPING1 in the retina and the choroid layer (the vascular layer next to the retina), the two areas affected by AMD. These proteins are involved in regulating a part of the body's innate immune system known as the "complement system". The findings suggest that the complement system is malfunctioning, attacking the retina and choroid layer.
"It seems counterintuitive that a generalised innate immunity defence system should result in a localised disease of the eye in the elderly," Says Professor Andrew Lotery from the University of Southampton, corresponding author on the study. "However, it is becoming increasingly clear from research that this is the case. Previous AMD genes have already implicated the 'alternate' complement pathway, and our paper shows that the 'classical' complement pathway is also involved in this process."

Eat oily fish at least once a week to protect your eyesight in old age

09 aug 2008--Eating oily fish once a week may reduce age-related macular degeneration (AMD) which is the major cause of blindness and poor vision in adults in western countries and the third cause of global blindness, according to a study published today in the American Journal of Clinical Nutrition.
There are two types of AMD, wet and dry. Of the two, wet AMD is the main cause of vision loss. A team of researchers across seven European countries and co-ordinated by the London School of Hygiene & Tropical Medicine sought to investigate the association between fish intake and omega 3 fatty acids with wet AMD, comparing people with wet AMD with controls. Participants were interviewed about their dietary habits including how much fish they ate and what type. Information on the main omega 3 fatty acids (docosahexaenoicacid (DHA) and eicosapentaenoic acid (EPA) was obtained by linking dietary data with food composition tables.
The findings show that people who habitually consume oily fish at least once a week compared with less than once a week are 50% less likely to have wet AMD. There was no benefit from consumption of non oily white fish. There was a strong inverse association between levels of DHA and EPA and wet AMD. People in the top 25% of DHA and EPA levels (300 mg per day and above) were 70% less likely to have wet AMD.
Astrid Fletcher, Professor of Epidemiology at the London School of Hygiene & Tropical Medicine, who led the study, commented: "This is the first study in Europeans to show a beneficial association on wet AMD from the consumption of oily fish and is consistent with results from studies in the USA and Australia. Two 3oz servings a week of oily fish, such as salmon, tuna or mackerel, provides about 500 mg of DHA and EPA per day".
The research team is not, however, recommending omega 3 supplements as the study did not investigate whether supplements would have the same benefit as dietary sources.
###
The EUREYE study was funded by the European Commission with additional support from the Macular Disease Society UK and the Thomas Pocklington Trust.
To contact Astrid Fletcher, please call the London School of Hygiene & Tropical Medicine on 0207 927 2802 / 07828 617 901 or email gemma.howe@lshtm.ac.uk

Current Smoking Linked to Age-Related Macular Degeneration

Laurie Barclay
January 16, 2008 — Current smoking was linked with an approximately 45% higher odds of developing age-related macular degeneration (AMD) vs never smoking, according to the results of the Beaver Dam Eye Study reported in the January issue of the Archives of Ophthalmology.
"Smoking affects risk factors hypothesized to be involved in the pathogenesis of AMD, eg, immune activation, depression of antioxidant levels, reduction of choroidal blood flow, decrease in luteal pigments in retina, reduction of drug detoxification by the retinal pigment epithelium (RPE), and nicotine potentiation of angiogenic activities," write Ronald Klein, MD, MPH, from the University of Wisconsin School of Medicine and Public Health in Madison, and colleagues. "The purpose of this article is to describe the association between baseline smoking status, age at initiation, duration, intensity, pack-years, age at quitting, and time from the baseline examination since quitting and the 15-year cumulative incidence and progression of AMD in the population-based Beaver Dam Eye Study."
In this population-based, longitudinal cohort study, 4926 people in Beaver Dam, Wisconsin, who were aged 43 to 84 years in 1987 and 1988, were examined between 1988 and 1990 and again at 5-year intervals for 15 years. Stereoscopic color fundus photographs were graded for AMD status.
After adjustment for age, sex, and baseline severity of AMD, people who were current smokers at baseline were at increased risk for incident early AMD during a 15-year follow-up vs those who never smoked (odds ratio [OR], 1.47; 95% confidence interval [CI], 1.08 - 1.99; P = .01). Current smokers were also at increased risk for progression of AMD (OR, 1.43; 95% CI, 1.05 - 1.94;P = .02).
Characteristics of smoking, such as intensity, pack-years smoked, duration, and age at initiation and quitting were not specifically associated with AMD outcomes. There was no apparent association between smoking status and incident signs of late AMD. Exposure to environmental tobacco smoke in nonsmoking individuals was not associated with the 5-year incidence of early AMD or progression of AMD.
Limitations of the study include small numbers of either exudative AMD or geographic atrophy, causing an inability to rule out the possibility of an association with smoking status; and limited power to observe a relationship between smoking and incidence of late AMD in people aged 65 years or older.
"Smoking appears to be related to the long-term incidence and progression of AMD," the study authors write. "This has important health care implications because early AMD increases the risk of developing late AMD and smoking behavior is modifiable."
The National Eye Institute, the National Institute of Aging, and Research to Prevent Blindness supported this study. The study authors have obtained funding.
Arch Ophthalmol. 2008;126:115-121.

Elevated C-Reactive Protein Linked to Age-Related Macular Degeneration

ROTTERDAM, The Netherlands, Oct. 8 -- Age-related macular degeneration appears linked with high baseline levels of C-reactive protein and associated inflammation, researchers here found.
As a patient's C-reactive protein level increased above the median of the study population, the risk of age-related macular degeneration increased, reported Paulus T.V.M deJong, M.D., Ph.D., of the Erasmus Medical Center here, and colleagues, in the October issue of Archives of Ophthalmology.
"Individuals with a high C-reactive protein level (>1.73 mg/L) within the normal range have a statistically significant higher risk of early and late aging macular degeneration," the researchers wrote.
The researchers added that they prefer the term "aging" to "age-related," given that age-related does not discriminate between the juvenile disorder and that associated with older age.
In a population-based study, they examined serum high-sensitivity C-reactive protein levels in 4,914 patients at risk for the disorder participating in the Rotterdam Study, a population-based study of chronic disabling diseases in older persons.
At the initial examination, from 1990 through 1993, blood samples were collected and color photos were taken of the macular area of each eye.
After a mean follow-up of 7.7 years, including three initial examinations, 561 cases of early and 97 cases of late incident age-related macular degeneration were identified.
After adjustment for age and sex, hazard ratios were 1.11 (95% CI, 1.02-1.21) per standard deviation increase in CRP level for early disease and 1.28 (CI, 1.02-1.60) for late disease.
Hazard ratios for early age-related disease increased per quartile increase in CRP level as follows: second quartile, 1.19 (CI, 0.94-1.52); third quartile, 1.29 (CI, 1.01-1.64); and fourth quartile, 1.33 (CI, 1.05-1.70).
The risk of late eye disease was higher in all the upper quartiles of high-sensitivity CRP, the researchers said.
This population-based cohort confirmed data from three earlier clinic-based studies indicating that baseline high sensitivity CRP levels were associated with early and late incident age-related macular degeneration, with the highest risks for patients with late disease.
This finding, they said, supports the theory that inflammation is a mechanism involved in the pathogenesis of the disorder in the general population.
Injury to the retinal pigment epithelium cells and possibly to the choroid caused by smoking, obesity, the toxic effect of light, and low antioxidant intake may induce age-related macular degeneration through a state of chronic inflammation, they said.
Chronic inflammation seems to be involved in the development of drusen, the white subretinal extracellular deposits that are a hallmark of the disorder. Analysis has found that drusen contain proteins associated with inflammation, such as fibrinogen, complement components, and CRP, the researchers said.
Evidence is accumulating that inflammatory and immune-associated pathways have a role in other degenerative diseases associated with advancing age, such as atherosclerosis and Alzheimer's disease.
Drusen components have been found in atherosclerotic plaques and deposits in Alzheimer's so that macular degeneration, atherosclerosis, and Alzheimer's may share a similar inflammatory pathogenesis, the researchers wrote.
It is possible that reducing CRP levels might lower the risk for the eye disorder, the researchers said. However, a substance that can selectively inhibit CRP synthesis has not yet been developed, to their knowledge, the investigators said.
The pathogenesis of the disorder is unclear, although beneficial effects for some modifiable risk factors such as smoking and hypertension have been noted.
Smoking and high body mass index increase CRP levels. Moderate alcohol intake, diets with a low glycemic index, and statin and multivitamin use reduce the protein's levels.
However, additional correction for smoking and obesity did not change the estimates in this study, they said. Nevertheless, they added, reducing both might be protective.
Differential misclassification was unlikely in this study, the researchers said, because the macular degeneration graders were masked for CRP status and because the data were collected without knowledge of age-related macular degeneration status.
CRP was measured only once, the researchers said, but this should not have been a problem. The protein has a half-life of about 19 hours, and concentrations seem to have been fairly stable for at least five years in most of the individuals.
"We consider C-reactive protein level a potential useful biological marker in profiling the risk of aging macular degeneration for individual persons," the authors concluded.
No financial conflicts were reported.
This study was supported by the Netherlands Organization for Scientific Research and by the following foundations: Optimix, Physico Therapeutic Institute, Blindenpenning, Sint Laurens Institute, Bevordering van Volkskracht, Blindenhulp, Rotterdamse Blindenbelangen Association, OOG, kfHein, Prins Bernhard Cultuurfonds, Van Leeuwen Van Lignac, Verhagen, and Elise Mathilde. An unrestricted grant was obtained from Topcon Europe BV (all awarded to Dr. de Jong). Primary source: Archives of OphthalmologySource reference: Boekhoorn, SS, et al "C-reactive Protein Level and Risk of Aging Macula Disorder" Arch Ophthalmol 2007;125: 1396-1401.

Consulting may prevent depression after vision loss

Thu Aug 16, 3:48 PM ET
Patients with age-related macular degeneration, a frequent cause of vision loss in the elderly, are less likely to develop depressive disorders in the short-term if they're taught problem-solving skills, new study findings suggest. However, the benefits don't seem to be maintained over time.
Age-related macular degeneration often leads to "irreversible vision loss, disability, and depression," write Dr. Barry W. Rovner, of Jefferson Medical College, Philadelphia, Pennsylvania, and colleagues. However, depression in these patients is rarely diagnosed or treated in during visits to the eye doctor.
The researchers examined whether problem-solving treatment could prevent depressive disorders in patients with recent vision loss. Problem-solving treatment is "a manual-driven psychological treatment" that teaches problem-solving skills: defining problems, setting realistic goals, implementing solutions, and evaluating outcomes.
Included in the study were 206 patients at least 65 years of age who were recently diagnosed with age-related macular degeneration in one eye and had pre-existing macular degeneration in the other eye. The patients were randomly assigned to problem-solving treatment or to the usual care. Therapists conducted 6 problem-solving sessions over 8 weeks in the patients' homes.
After 2 months, the team assessed the short-term treatment effects, and after 6 months, evaluated the maintenance effects. The main outcome measures included diagnoses of major or minor depression, as defined by the Diagnostic and Statistical Manuel-IV; scores on the National Eye Institute Vision Function Questionnaire-17; and the number of patients who had to relinquish activities that were important to them.
At 2 months, the incidence of depressive disorders was significantly lower in problem-solving group compared with the control group -- 11.6 percent versus 23.2 percent, respectively. The researcher estimated that patients in the problem-solving group were 61 percent less likely to develop a depressive order compared with the control group. The number of patients needed to treat to prevent one case of depression was nine.
The odds of having to give up a valued activity were also significantly reduced with problem-solving treatment. The investigators found that this probably mediated the relationship between problem-solving treatment and depression.
The changes in scores on the National Eye Institute Vision Function Questionnaire-17, a subjective measure of vision-related task difficulty, showed that the problem-solving group improved according to patients' subjective reports, despite the fact that there were no changes in visual acuity. There were also no changes in acuity among the control patients, but these subjects did report declines in their ability to perform vision-related tasks, Rovner's team reports.
Most short-term benefits had diminished by 6 months, although subjects in the problem-solving group were less likely to suffer persistent depression. "Booster or rescue treatments may be necessary to sustain problem-solving treatment's preventative effect," the investigators conclude.
SOURCE: Archives of General Psychiatry, August 2007.

Smoking Hikes Risk of Age-Related Macular Degeneration

SIDNEY, Australia, Aug. 14 -- Age-related macular degeneration is four times more likely to affect current smokers than those who never smoked, found researchers here.
Current smokers had a nearly four-fold higher risk of the serious late, but not early, macular degeneration compared with those who had never smoked, the researchers said.
The risk also held for past smokers who were three times likelier to have geographic atrophy, Jie Jin Wang, M.Med., Ph.D., of the University of Sydney here, and colleagues, reported in the July issue of the Archives of Ophthalmology.
Late age-related macular degeneration, the more severe form of the eye disorder with the poorest prognosis, is thought to share risk factors with cardiovascular disease. Although there was a suggestion of a causal relationship between lipid levels and the eye disease, the interactions were not statistically significant, the researchers reported.
The findings emerged from a prospective study of 2,454 Australians, ages 49 and older at baseline (1992 through 1993), with a mean age of 64.4. Of the participants 57.6% were women.
Participants were examined five years or 10 years later, or both. Retinal photographs were used to assess macular degeneration, while smoking status was recorded at each interview. Body mass index and blood pressure were also measured.
After controlling for age, sex, and other factors, current smokers had a 3.9 times relative risk (95% confidence interval, 1.7-8.8), on average five years earlier than never smokers.
Past smokers had 3.4 relative risk of geographic atrophy (CI, 1.2-9.7), suggesting some benefit from smoking cessation and supporting a likely causal effect between smoking and macular degeneration, the researchers said.
The effect of past smoking was not evident at five years, the researchers said, but appeared after 10 years, with the risk persisting above that of never-smokers for a considerable time after quitting smoking.
Past smokers were divided above and below the median of 17 years for smoking cessation. The risk of late age-related macular degeneration was 1.9 (CI, 0.8-4.4) for those who quit fewer than 17 years earlier, and 1.2 (CI 0.6-2.7) for those with 17 or more years smoke-free.
Combined exposure to current smoking and the lowest level of HDLs, the highest ratio for total cholesterol to HDL cholesterol, or low fish consumption was associated with a higher risk of the eye disease than the effect of any risk factor alone. However, these interactions were not statistically significant, the researchers said.
Data from other studies have not shown a consistent association between lipid levels and age-related macular degeneration. The present findings, the investigators said, should therefore be interpreted with caution, as chance findings cannot be excluded.
A biological model involving atherosclerosis could explain the joint effects of smoking and lipid levels on risk. For example, it has been postulated that lipid accumulation in the sclera and the Bruch's membrane increases choroidal vascular resistance, causing leakage and deposition of proteins and lipids in the membrane.
Animal models support a role for cholesterol and the possibility of joint effects in the pathogenesis of macular degeneration, the researchers said.
Furthermore, they added, high levels of polyunsaturated fatty acids in the retina support the biological plausibility of a protective effect from fatty acids derived from fish intake.
The researchers wrote that this is only the second (after the Beaver Dam Eye Study) prospective population-based study to assess the long-term association between baseline smoking and age-related macular degeneration. A strength of the study, they wrote, included its long follow-up, and detailed side-by-side comparison of the eye-examination photographs.
An important source of bias in this study was the loss to follow-up of about 25% of the survivors. Those alive but lost to follow-up were more likely to be current smokers at baseline, leading to an underestimation of the relationship between current smoking and macular degeneration.
Alternatively, smokers diagnosed with macular degeneration may have been more likely to attend follow-up than smokers without vision problems, leading to an apparent association between smoking and the vision disorder when none was really present.
These findings add evidence to a possible causal relationship between smoking and the long-term risk of late, but not early, age-related macular degeneration, the researchers wrote.
In addition, these results suggest a possibly greater joint effect in persons with low HDLs, a high ratio of total cholesterol to HDLs, and low fish consumption.
"This supports speculation that macular degeneration is a condition with multiple etiologic factors, and such joint effects contributing to the pathogenesis of macular degeneration could mirror the pathogenesis of cardiovascular disease," Dr. Wang concluded.
No financial disclosures were reported. This study was supported in part by grants from the Australian National Health and Medical Research Council.Primary source: Archives of OphthalmologySource reference: Tan JSL, et al "Smoking and the Long-term Incidence of Age-Related Macular Degeneration" Arch Ophthalmol 2007; 125: 1089-1095.

Eye Disease On The Rise Among Older Americans, Few Realize Risk

01 Aug 2007 A new national health survey of 1,200 Americans conducted for the American Academy of Ophthalmology finds that most Americans are unaware of the risks associated with age-related eye diseases, despite a projected 65 percent spike in those conditions by the year 2020. The survey indicates that few Americans see themselves truly at risk for eye disease and that populations most at risk for developing eye disease are unaware of the factors that make them susceptible. Overall, most Americans rank blindness and vision loss relatively low on their list of health concerns. The survey, conducted by Greenberg Quinlan Rosner Research, finds only 11 percent of Americans perceive themselves at high risk for eye disease.[i] While Americans age 65 and over are the most at-risk population for eye disease, only 10 percent believe they are personally at risk and more than a third of those in this age group do not even get annual eye examinations. Another high-risk group, those with a family history of eye disease, knows strikingly little about specific risk factors and is no more likely to get screened than people without a family history of eye disease. Only 15 percent of all respondents were correctly able to identify half or more factors from a list of risk factors for age-related macular degeneration, cataracts, diabetic retinopathy, glaucoma and dry eye presented in the survey. Age-related eye diseases including cataracts, diabetic retinopathy, glaucoma and age-related macular degeneration are expected to dramatically increase-from 28 million today to 43 million by the year 2020.[ii] Left untreated, these diseases can cause serious vision loss and blindness. At the heart of this upsurge lie America's 78 million baby boomers, who will increasingly face the effects of eye diseases as they get older. Despite these statistics, Americans remain relatively unconcerned about vision loss. The Academy's survey reveals that less than a quarter of Americans (23 percent) are very concerned about losing their vision, while a majority feel weight gain or joint and back pain are of greater concern than vision loss. "The stark reality is that millions of people will suffer significant vision loss and blindness because they don't know the risks," said H. Dunbar Hoskins Jr., MD, executive vice president of the American Academy of Ophthalmology. "We're taking action against this pending epidemic by educating the American public on the steps they can take to prevent vision loss and blindness." To that end, the Academy, the world's largest association of eye physicians and surgeons, is issuing a new eye disease screening recommendation for aging adults and is launching a new public initiative called EyeSmart™ to educate Americans about the risks they face. The Academy now recommends that adults with no signs or risk factors for eye disease get a baseline eye disease screening at age 40-the time when early signs of disease and changes in vision may start to occur. Based on the results of the initial screening, an ophthalmologist will prescribe the necessary intervals for follow-up exams. For individuals at any age with symptoms of or at risk for eye disease, such as those with a family history of eye disease, diabetes or high blood pressure, the Academy recommends that individuals see their ophthalmologist to determine how frequently their eyes should be examined. "Much like regular mammograms and diabetes screenings, eye disease screening will help identify signs of disease at an early stage, when many treatments can have the greatest impact," said Dr. Hoskins. The new recommendation does not replace regular visits to the ophthalmologist to treat ongoing disease or injuries, or vision examinations for eye glasses or contact lenses. EyeSmart will support the Academy's new eye health recommendations by empowering individuals and families to take charge of their eye health. The Academy is partnering with EyeCare America®, a public service program of the Foundation of the American Academy of Ophthalmology, on the effort. "With EyeSmart, age-related eye disease will no longer be a question mark in the minds of the American public," said Richard P. Mills, MD, MPH, chairman of EyeCare America. "The campaign allows all Americans to get informed about age-related eye disease, understand their risks and take action." EyeSmart draws upon the combined resources of the Academy, state and local ophthalmology societies and other partners to deliver critical information on age-related eye diseases through multiple health information channels, including doctors' offices and grassroots networks. The EyeSmart Web site, http://www.geteyesmart.org, delivers eye disease and risk information and a searchable database of local ophthalmologists. In order to impact the chief health care decision makers of American families, EyeSmart will focus on reaching women over 40. These women are more likely to serve as caregivers for their own families and increasingly their aging parents, and they frequently act upon and share with friends and loved ones positive health care information. EyeSmart also aims to reach people who don't traditionally consider themselves at risk, such as individuals who do not wear glasses or contacts. The survey revealed that 96 percent of individuals without glasses or contacts do not think they are at high risk for eye disease. Wearing glasses or contacts has no impact on contracting age-related eye diseases. "The fact is that everyone is at risk. More than half of all Americans will have some form of eye disease as they get older," Dr. Hoskins said. "We believe that if Americans know their risks, they will take the steps necessary to maintain good eye health. We want Americans to get EyeSmart to help reduce severe vision loss and blindness." For an executive summary of the survey and more information on specific age-related eye diseases, visit http://www.geteyesmart.org.About the American Academy of OphthalmologyThe Academy is the world's largest association of eye physicians and surgeons - Eye M.D.s - with more than 27,000 members worldwide. Eye healthcare is provided by three sources - opticians, optometrists and ophthalmologists. It is the ophthalmologist, or Eye M.D., who can treat it all: eye diseases and injuries, and perform eye surgery. To find an Eye M.D. in your area, visit the Academy's Web site at http://www.aao.org .About EyeCare America®Established in 1985, EyeCare America, a public service program of the Foundation of the American Academy of Ophthalmology, is committed to the preservation of sight, accomplishing its mission through public service and education. EyeCare America provides eye care services to the medically underserved and for those at increased risk for eye disease through its corps of 7,200 volunteer ophthalmologists dedicated to serving their communities. More than 90 percent of the care made available is provided at no out-of-pocket cost to the patients. EyeCare America includes programs for seniors, glaucoma, diabetes, AMD and children, and is the largest program of its kind in American medicine. Since its inception, EyeCare America has helped more than 860,000 people. EyeCare America is a non-profit program whose success is made possible through charitable contributions from individuals, foundations and corporations. More information can be found at: http://www.eyecareamerica.org[i] Americans, Eye Health, and Eye Disease National Survey, Greenberg, Quinlan & Rosner Research Inc., June, 2007. Telephone survey of 1,200 adults. Margin of error +/- 2.8 percentage points.[ii] The Eye Disease Prevalence Research Group, Cause and Prevalence of Visual Impairment Among Adults in the United States, Archives in Ophthalmology 2004;122;477-485.

Zinc Found To Be A Link In Age-Related Macular Degeneration

An international research team including scientists at the University of Texas Medical Branch at Galveston (UTMB) and the Galveston-based spinoff Neurobiotex, Inc. has found high levels of zinc in deposits in the eye that are an indication of age-related macular degeneration (AMD) - the leading cause of blindness in the elderly in the developed world. The finding, published this month in the journal Experimental Eye Research, contributes to a better understanding of AMD and could facilitate the development of effective treatments, said UTMB ophthalmologist Erik van Kuijk, senior author of the study. AMD is a form of macular disease that affects the eye's central retina and afflicts millions of people (30 percent of them over 75 years old) in the United States alone. It is associated with defects of retinal pigment epithelial cells (RPE), the failure of which leads to progressive loss of vision. Despite the potentially devastating impact on patients' quality of life, no successful therapy to stop or reverse the progression of AMD is available in the majority of cases. An early sign and a presumed trigger of the eye disease is the formation of microscopic plaques, called "drusen," in the eye. Exactly what these plaque-like drusen do and why they form is not yet fully understood, the researchers noted. "We have discovered that the drusen in the eyes of those with AMD have very high levels of zinc," said van Kuijk, associate professor in the UTMB Department of Ophthalmology and Visual Sciences.