A study recently presented at the Association for Research in Vision and Ophthalmology 2010 annual meeting showed and association between aspirin use and macular degeneration.  According to Dr. Paulus de Jong there had been several studies that had found an association as well as several studies that had found no association and this study was meant to “disentangle the conflicting evidence” between aspirin use and macular degeneration.

The study examined 4691 patients 65 years of age or older.  Study participants were asked about their use of aspirin as well as other possible risk factors known to contribute to macular degeneration.

The study concluded that frequent aspirin use appeared harmful for the aging macula and contributed to the onset of the eye disease macular degeneration.

Dr. de Jong indicated patients should not stop taking aspirin for cardiovascular disease but should look at other medications if it is used as a pain killer.  Others have expressed concerns over the study saying that while there is an association between aspirin use and macular degeneration there may be other factors not explored, including the reasons for taking the aspirin.

More research into aspirin use and macular degeneration is required before any definite link to the eye disease is known.

According to the study’s senior author, Dr. Robert J. Nicolosi, “Two eggs per day is probably all that is needed to maximize blood levels of lutein and zeaxanthin as well as macular pigment optic density (MPOD) status.”  Both lutein and zeaxanthin have been shown in other studies to help lower the risk associated with macular degeneration.

Study subjects were all older adults taking statins.  Their low-density-lipoprotein cholesterol levels were unaffected even when they ate as many as four yolks per day.  Out of the 52 participants in the study, serum lutein increased by an average for 16 percent after the 2-yolk phase and 24 percent after the 4-yolk phase of the study when compared to the baseline.  Serum zeaxanthin increased by 36 percent and 82 percent respectively.  Macular pigment optic density increased significantly after both phases, but only among individuals with low baseline density values.

While these results may indicate a lower risk of dry macular degeneration, there is a current study underway to evaluate the consumption of 12 eggs per week on the progression of dry macular degeneration.  The senior author points out “Although this was only a 5-week study and the 1-year data are not ready for comment, it would seem to me that physicians could consider that those patients on statins, who have early stage macular degeneration, could be prescribed 2 egg yolks per day.”

Dr. Nicolosi also added that “increases in blood levels of lutein and zeaxanthin and MPOD correlate well with the risk for age-related macular degeneration.”

The impact of such nutrients supports other studies that have indicated that the risk of macular degeneration for individuals can be lessened.

Researchers used a large prospective study and examined people with the eye disease macular degeneration and found there was a 50 percent greater risk of heart disease than those with it.  In examining the available data, it was shown that there was no increased risk associated with macular degeneration and stroke.

“This provides further support that age-related macular degeneration is associated with underlying systemic vascular disease,” researchers said.  They noted that evidence suggesting that the eye disease and heart disease share common mechanisms is increasing.

During the study, researchers examined 1,786 patients without heart disease and 2,228 patietns with stroke as a baseline.  All patients were between the ages of 69 and 97, and had been enrolled in the Cardiovascular Heart Study.  Macular degeneration was evaluated using photographs taken at the time of examination.

Of those patients free of heart disease, 303 developed the disease, while 198 of those free of stroke developed the disease.  Early macular degeneration was hown to occur more in those patients with heart disease than those without.  The association of heart disease with macular degeneration was shown even when things such as age, gender, race, blood pressure and smoking were accounted for in the study.

However, late macular degeneration was not associated with heart disease.  Both early macular degeneration and late macular degeneration were not associated with stroke.

Researchers also discovered the associated between macular degeneration and heart disease was stronger in younger patients.  Those people between 69 and 78 years of age had and 80 percent higher risk for heart disease than those without the eye disease.  The risk was only 45 percent for those patients from 79 to 97.

The researhers indicated that their findings were consistent with other literature indicating the association between heart disease and macular degeneration.  “Our findings,” they concluded, “may have broader implications of cardiovascular safety for the many patients with age-related macular degeneration who are treated with long-term antivascular endothelial growth factor therapy.”

With the risk of heart disease increasing when a person suffers from macular degeneration, proper eye health is important.

Primary source: Ophthalmology
Source reference:
Sun C, et al “Age-related macular degeneration and risk of coronary heart disease and stroke: The Cardiovascular Health Study” Ophthalmol 2009; DOI: 10.1016/j.ophtha.2009.03.046.

In the EUREYE study, participants aged 65 and over underwent an eye examination that included digital retinal photography.  These images were graded at a single centre and a structured questionnaire was administered, examining the risk factors for macular degeneration, including diabetes.

After the data was collected, models were used to examine the association between macular degeneration and diabetes, including the various stages of the eye disease.  The models accounted for demographic, behavioural, dietary and medical factors as well.

The photographic images were graded according to an international classification system for macular degeneration.  Classification consisted of no signs of macular degeneration (stage 0), early macular degeneration (stage 1 – 3) and late macular degeneration (stage 4).  Late stage macular degeneration was further subdivided into neovascular macular degeneration and geographic atrophy.

Data on diabetes history were available in 2117 control subjects without macular degeneration, 2182 participants with early stage macular degeneration, 49 with geographic atrophy and 101 with neovascular macular degeneration.  After adjusting the data, subjects with neovascular macular degeneration compared with controls had increased the odds for diabetes.  Those participants with early macular degeneration had no increased odds for diabetes when compared with those without the eye disease.

In the EUREYE study as postive association of diabetes and neovascular macular degeneration was found.  This has led to the hypothesis that diabetes associated with neovascular macular degeneration and not geographic atrophy may suggest a different pahtogenesis in the two for the eye disease and this may require further study.

Finding an association between diabetes and macular degeneration in the EUREYE study is not consistent with other published studies.

The report showing the lower risk of contracting the eye disease was reported in the April 2008 issue of Archives of Ophthalmology.

Macular degeneration is the leading cause of vision loss and blindness among older adults.  This eye disease is reported to affect an estimated 1.75 to 10 million people in the United States alone.  The report showing that women who had taken hormone replacement theory may be at a lower risk of developing advanced macular degeneration suggested estrogen may play a role in the development of this eye disease.

Diane Feskanich, SC.D, of Brigham and Women’s Hospital and Harvard Medical School, Boston and colleagues assessed estrogen-related factors such as postmenopausal use, past use of oral contraceptives, ages at first period and menopause and childbirth history in 74,9996 post-menopausal women in the Nurse’s Health Study.  Between 1980 and 2002, 554 of the women had developed early stage macular degeneration and 334 had developed neovascular macular degeneration.

“Current postmenopausal hormone users had a notable 48 percent lower risk of neovascular AMD compared with those who had never used postmenopausal hormones, although risk did not decline linearly with longer durations of use,” the authors write. “Risk was lowest for postmenopausal hormone users who had used oral contraceptives in the past.”

In contrast, the risk of developing early stage macular degeneration was 34 percent higher in current postmenopausal  hormone users and oral contraceptive was not associated wiht early stage macular degeneration risk.  “The higher risk of early age-related macular degeneration among postmenopausal hormone users was unexpected and in apparent conflict with the observed inverse association for neovascular age-related macular degeneration,” the authors write. Women who had given birth had a 26 percent lower risk of early macular degeneration. (Source: Archives of Ophthalmology. 2008;126[4]:519-524.)

The risks associated with HRT have been well document and researched in the last several years.  These include increased risk of both heart disease and breast cancer.  Women who are in a higher risk category (ie family history of heart disease, breast cancer and macular degeneration) should discuss treatment options with their physicians and determine if HRT treatment may be of use to lower the risks associated with macular degeneration.

Macular degeneration affects the elderly and the aging.  There is little that can be done to prevent aging, but research has shown that smokers are at a much higher risk to developing macular degeneration than non-smokers.  The obvious choice for preventing this eye disease is to quit smoking.

Smokers are four times more likely to develop macular degeneration than non-smokers.  (Tan JSL, et al “Smoking and the Long-term Incidence of Age-Related Macular Degeneration” Arch Ophthalmol 2007; 125: 1089-1095.)

A research study at the Harvard Medical School’s Schepens Eye Research Institute showed a correlation between the density of retinal pigment and smoking.  As smoking increased, the density of the retina decreased.  The pigment in the eye is the protection mechanism that acts as an antioxidant and blocks harmful UV rays from the retina.  If this pigment is decreased, s cientists believe that this contributes to the increased risk of developing macular degeneration.

Even if a person were to quit smoking, there is still an increased risk of developing macular degeneration.  Pas smokers are still in a higher risk category than non-smokers of developing this eye disease.

However quitting smoking has more benefits to one’s health than just lowering the risk of developing macular degeneration.

The more common factors associated with age-related macular degeneration (AMD or ARMD) include:

• Aging;
• Smoking;
• High blood pressure (Hypertension);
• Heredity;
• Obesity and inactivity;
• Gender; and
• Diet

The most significant of these risk factors associated with macular degeneration are aging and smoking.  The effects of aging are become more pronounced as individuals get older.  After the age of 50, the risks associated with macular degeneration begin to increase.  Smoking is a major risk factor, causing severe vision loss in approximately 25% of all macular degeneration cases.  In 2006, a study showed that people living with someone who smoked doubled their chances of being diagnosed with the eye disease macular degeneration.  (British Journal of Ophthalmology).

Studies have also shown that high blood pressure or hypertension may also increase the risk of AMD.  As well, those people who are inactive and overweight were more than double the risk of developing advanced forms of age related macular degeneration (Archives of Ophthalmology, 2003).  Regular exercise at least 3 times a week have been shown to reduce the risks associated with age related macular degeneration.

Gender also plays a role, primarily because women live longer than men and age is one of the most significant causes of AMD.

Heredity has also been shown to play a significant role into whether you are at risk of macular degeneration.  People whose relatives have been diagnosed with the eye disease are 50 percent as likely to develop the macular degeneration versus just 12 percent for those who have no family member with a history.  Individuals with family members who have been diagnosed with age-related macular degeneration should make it a point to seek regular eye examinations and notify their doctor that they may be at higher risk of the eye disease.

People who have diets that are saturated in fats are also at a higher risk of being diagnosed with macular degeneration.

It is important to keep in mind that with all these associated risk factors, anybody can be diagnosed with age-related macular degeneration.  Regular eye examinations are imperative, especially when you reach the age of 50 and beyond.  Just because you may not be considered a high risk for macular degeneration, proper eye care is crucial.

If you are in a higher risk category, familiarity with the associated risks of macular degeneration is important.  With some of the risk factors of this eye disease founded in diet and habits such as smoking, lowering the risk of macular degeneration can be accomplished through lifestyle changes.