Nov 21 2009

Cataract Surgery Does Not Increase Risk of AMD Progression

Published by under Cataracts,Macular degeneration

Researchers have found that cataract surgery is not associated with an increased risk of age-related macular degeneration (AMD) progression in patients with non-neovascular AMD.

Surgeons enrolled 108 patients with nonneovascular AMD who were awaiting cataract surgery. Fluorescein angiography was performed preoperatively, and again at postoperative week 1, month 3, and month 12 visits.

After 12 months, neovascular AMD developed in only 3 of 65 eyes (4.6%) that did not have neovascular AMD at the preoperative visit or the one-week postoperative visit.  This statistic is consistent with an estimated one-year progression rate in the general AMD population.

Results of this study, published in the November issue of the Archives of Ophthalmology, state that the low incidence of neovascular AMD development between 1 week and 1 year after cataract surgery did not support the hypothesis that cataract surgery increases the risk of AMD progression.

Researchers also noted that  several eyes appeared to have disease progression on postsurgery week 1 fluorescein angiograms, suggesting that many cases of presumed progression to neovascular AMD following cataract surgery may have been present prior to cataract surgery, but not recognized owing to lens opacity.

Read other studies about macular degeneration at the Natural Eye Care site

SOURCE:  Progression of Age-Related Macular Degeneration After Cataract Surgery, Dong, et al, Arch Ophthalmol. 2009;127(11):1412-1419.

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Oct 24 2009

Macular Degeneration Patients: Blood Thinners Increase Risk of Retinal Hemorrhage

Published by under Macular degeneration

People with age-related macular degeneration (AMD) who are taking anticoagulant and antiplatelet drugs such as aspirin, warfarin, and clopidogrel run a significant risk of retinal hemorrhage.  

A study presented at the Retina Congress 2009 reviewed the records of 195 eyes in 195 patients, average age 83, of whom 96 were taking antiplatelets and anticoagulants on a daily basis.

Of the patients taking antiplatelets or anticoagulants, 63% developed retinal hemorrhage compared with 29% who were not taking these drugs.  It is estimated that 7.6 patients out of 100 would develop retinal hemorrhage each year when taking these drugs.  The risk of retinal hemorrhage was highest among patients who were using multiple drugs.

Since taking the patient off the blood-thinning agent is not an option, study authors suggest that ophthalmologists follow these patients closely.  It is recommended that information about a patient’s use of antiplatelets and anticoagulants should be noted prominently on the patients’ charts.

The 2009 Retina Congress is a combined meeting of the American Society of Retina Specialists, the Macula Society, and the Retina Society.

Source:  “The Association of Antiplatelets and Anticoagulants With Intraocular Hemorrhage in Patients With Exudative Age-Related Macular Degeneration,” http://www.asrs.org/

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Aug 26 2009

New Macular Degeneration Research: Scientists Grow New Retinal Cells

Researchers at the University of Wisconsin have successfully grown light-sensing retinal cells from human skin cells. 

The ability to grow retinal cells may someday be used to treat degenerative eye diseases such as macular degeneration and retinitis pigmentosa by enabling doctors to repair damage to the retina with new cells generated from the patient’s skin.

Scientists at the University of Wisconsin manipulated human skin cells to act like embryonic stem cells, which can be used to grow into any tissue in the body. 

The study, published in the journal Proceedings of the National Academy of Science, indicates that the ability to create human retinal cells helps researchers better understand how eyes develop, enabling them to better treat genetic eye conditions.

SOURCE:  Modeling early retinal development with human embryonic and induced pluripotent stem cells, Meyer, et al, Proceedings of the National Academy of Science, http://www.pnas.org/content/early/2009/08/24/0905245106.abstract

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Jun 25 2009

Lutein and Zeaxanthin May Help Fight Early AMD

Published by under Macular degeneration

Oral supplementation with lutein and zeaxanthin with coantioxidants may improve vision at 36 months for those at high risk for progression to late age-related macular degeneration (AMD).

In the Carotenoids and Co-Antioxidants in Age-Related Maculopathy (CARMA) study, presented at the Association for Research in Vision and Ophthalmology (ARVO) 2009 Annual Meeting, researchers examined the effects of supplementation with serum lutein and zeaxanthin plus coantioxidants (vitamins C and E and zinc) on visual function and the progression from early to late stages of AMD.

A total of 433 participants in the United Kingdom with early AMD in at least one eye, or any level of AMD in the study eye and late-stage AMD in the fellow eye, received either carotenoids plus coantioxidants or a placebo.

Study participants were examined at 12, 18, 24, 30, and 36 months. Although no statistically significant difference was seen in best corrected distance visual acuity (BC DVA) at 12 months, at the 36 month follow-up researchers did note an improved BC DVA.

Investigative team member Usha Chakravarthy, MD, PhD, from Queens University of Belfast in Northern Ireland concluded that supplementation with lutein and zeaxanthin results in better macular function in patients with early AMD. He also noted that the eyes of people who had high serum (lutein) demonstrated a less severe early AMD change over time, and suggested that supplementation may prove beneficial in preventing progression to late AMD.

Learn about self-help for macular degeneration, including recommended diet and supplements containing lutein and zeaxanthin at the Natural Eye Care website

SOURCE: ARVO 2009: Lutein, Zeaxanthin Supplements May Result in Better Macular Function in Early AMD, Chakravarthy, et al, The Association for Research in Vision and Ophthalmology (ARVO), May 4, 2009.

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Jun 25 2009

Macular Degeneration Research Targets CCR3 Protein

Published by under Macular degeneration

Researchers at the University of North Carolina at Chapel Hill School of Medicine and the University of Kentucky have identified a new target for the diagnosis and treatment of age-related macular degeneration.

In a study published by the journal Nature, researchers demonstrate that blocking the activity of a specific protein, called CCR3, can reduce the abnormal blood vessel growth that leads to macular degeneration. Targeting this new protein may prove to be safer and more effective than the current treatment for the disease, which is directed at a protein called vascular endothelial growth factor or “VEGF.”

When researchers blocked CCR3, either with drugs or through genetic engineering, they saw a decrease in the generation of abnormal blood vessels. Drugs targeting CCR3 were significantly more effective than those targeting VEGF, which could represent a new therapy for the two-thirds of patients who do not respond to current treatment.

Study authors hope that this discovery may enable physicians to catch the disease in its earliest stages, before blood vessels have fully infiltrated and destroyed the central portion of the eye’s retina (the macula) to cause vision loss.

“It would be much better to prevent the disease in the first place,” said study co-author and principal investigator of the UNC study site, Mary Elizabeth Hartnett, M.D., a professor of ophthalmology in the UNC School of Medicine. “An exciting implication of this study was that the CCR3 protein could be detected in early abnormal blood vessel growth, giving us the opportunity to prevent structural damage to the retina and preserve vision.”

Learn more about macular degeneration at the Natural Eye Care web site

Read other studies about macular degeration

Source: Study suggests new approach to common cause of blindness, Hartnett, et al, June 14, 2009, href=”http://www.unchealthcare.org/site/newsroom/news/2009/June/hartnett?searchterm=macular+degeneration

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Jun 11 2009

More good fat, less bad, reduces age-related macular degeneration risk

Published by under Macular degeneration,Nutrition

In the first study, Jennifer S.L. Tan, MBBS, BE at the University of Sydney, Australia and her colleagues evaluated data from 2,454 participants in the Blue Mountains Eye Study of men and women aged 49 and older. Those who consumed one serving of fish per week were shown to have a 31 percent lower adjusted risk of developing early AMD compared with those who consumed less.

In the second article, Elaine W. T. Chong, MD, PhD, of the Centre for Eye Research Australia and her associates evaluated data from 6,734 men and women aged 58 to 69 who participated in the Melbourne Collaborative Cohort Study. Dietary questionnaires completed between 1990 and 1994 were analyzed for the intake of various foods and individual fatty acids. Follow up examinations conducted between 2003 and 2006 detected 2,872 cases of early age-related macular degeneration and 88 cases of late disease.

A high intake of trans-unsaturated fats was associated with a significant increase in late macular degeneration, with those whose intake was categorized as among the top 25 percent of participants having a 76 percent greater risk than those whose intake was among the lowest fourth.

Olive oil emerged as protective against late disease. When those who reported consuming at least 100 milliliters per week olive oil were compared with those who consumed less than 1 milliliter per week, they were found to have a 52 percent lower risk of late AMD.

For early AMD, those whose omega-3 fatty acid intake was among the top 25 percent had a 15 percent lower risk compared with those whose intake was among the lowest quarter.

For more information on nutrition and macular degeneration and related research studies, see NaturalEyeCare’s Section on Macular Degeneration.

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May 18 2009

AMD Linked to Cognitive Decline

Published by under Macular degeneration

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 (AMD). 

A new study published in the Archives of Ophthalmology reviews the association between cognitive function decline and the onset of AMD.

“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 with the Centre for Eye Research Australia at the University of Melbourne.

2088 participants aged 69 to 97 years who participated in the Cardiovascular Health Study were assessed for AMD.  Cognitive function was evaluated using the Digit Symbol Substitution Test (DSST) and the Modified Mini-Mental State Examination. Participants were also evaluated for dementia using detailed neuropsychological testing.

After controlling for age, sex, race, and study center, participants with low DSST scores were more likely to have early AMD than were participants with higher DSST scores.   In analysis that also controlled for education, systolic blood pressure, total cholesterol level, diabetes mellitus, smoking status, and apolipoprotein E genotype, the association was even stronger.

There was no association of dementia or Alzheimer disease with early AMD.

Read other studies on AMD

See tips on preventing vision problems with a focus on nutrition, exercise, lifestyle changes, and a positive mental approach to life at Natural Eye Care

SOURCE:  Early Age-Related Macular Degeneration, Cognitive Function, and Dementia – The Cardiovascular Health Study, Baker, et al, Arch Ophthalmol. 2009;127(5):667-673.

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May 14 2009

Foods to Fight Macular Degeneration

Researchers have released a new study showing that regular consumption of fish, omega-3 polyunsaturated fatty acids, and nuts helps protect against age-related macular degeneration (AMD).

The study, published in the Archives of Ophthalmology, assessed the relationship between dietary fatty acids and the 10-year incident of AMD.

Scientists examined 3654 elderly Australian participants at baseline and re-examined 2454 of these participants five and/or ten years later.  Participants completed a food frequency questionnaire.

The findings confirmed many previous studies on AMD.  After adjusting for age, sex, and smoking:

  • one serving of fish per week was associated with reduced risk of early AMD primarily among participants with less than the median linoleic acid consumption
  • findings were similar for consumption of long-chain omega-3 polyunsaturated fatty acids:  one to two servings of nuts per week was associated with reduced risk of early AMD 
  • protective associations between nut consumption and reduced risk of pigmentary abnormalities were seen among nonsmokers, participants with less than the median ratio of serum total to high-density lipoprotein cholesterol, and those with beta carotene intake greater than the median level.

This study provides evidence of protection against early AMD through:

  • regular consumption of fish and nuts
  • greater consumption of omega-3 polyunsaturated fatty acids
  • low intakes of foods rich in linoleic acid

Read more about AMD and natural eye care

Learn which foods to eat to help maintain good eye health

SOURCE:  Dietary Fatty Acids and the 10-Year Incidence of Age-Related Macular Degeneration, The Blue Mountains Eye Study, Tan, et al, Arch Ophthalmol. 2009;127(5):656-665.

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Apr 16 2009

Researchers Forecast Substantial Increase in AMD by 2050

Researchers predict age-related macular degeneration (AMD) will increase substantially by 2050, as the U.S. population ages, but the use of new and existing therapies can mitigate the effects of the condition.

A significant preventative therapy named in this study is the use of antioxidant vitamins to slow the progression of AMD from early to late stages.  Other treatments reviewed include laser and photodynamic therapies and anti-VEGF injections.

Scientists from the Research Triangle Institute International in North Carolina simulated cases of early AMD, choroidal neovascularization (CNV), geographic atrophy (GA), and AMD-attributable visual impairment and blindness with 5 universal treatment scenarios:

  1. no treatment;
  2. focal laser and photodynamic therapy (PDT) for CNV; 
  3. vitamin prophylaxis at early-AMD incidence with focal laser/PDT for CNV; 
  4. no vitamin prophylaxis followed by focal laser treatment for extra and juxtafoveal CNV and anti-vascular endothelial growth factor treatment; and 
  5. vitamin prophylaxis at early-AMD incidence followed by CNV treatment, as in scenario 4.

From the results of this analysis, the researchers predicted that cases of early AMD will increase from 9.1 million in 2010 to 17.8 million in 2050 across all scenarios, but that existing medical therapies have the potential to reduce the visual impairment and blindness attributable to AMD by as much as 35 percent, translating to 565,000 fewer cases of visual impairment and blindness in 2050.

Learn about good food sources of antioxidants

Read about antioxidant vitamins important in the treatment of macular degeneration

SOURCE:  Forecasting age-related macular degeneration through the year 2050: the potential impact of new treatments, Rein, et al,  Arch Ophthalmol. 2009 Apr;127(4):533-40.

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Apr 10 2009

Macular Degeneration: Techniques for Refocusing Vision

Although individuals with age-related macular degeneration (AMD) lose central vision, their peripheral vision often remains intact.   The Macular Disease Society (based in the UK) has developed a training scheme to help people use the undamaged parts of their eyes to read and identify faces. 

According to their research, people can be taught to use their peripheral vision to compensate for damage to their central vision, using “eccentric viewing” and “steady eye techniques”.   When someone with central vision loss looks directly at an object it may disappear or appear distorted, but when they look above, below, or to one side of it, they see it more clearly.

Eccentric viewing helps people learn where to focus their gaze to make their vision better.  Once this position is identified, they can be taught how to read again using the steady eye technique:  instead of moving the eyes from left to right to read a sentence, the person can keep their eyes completely still and move the text to the left so that each word in turn moves into the area of best vision.

Learn more about macular degeneration

SOURCE:  BBC News Channel, April 10, 2009, http://news.bbc.co.uk/1/hi/health/7958838.stm

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