Aspirin Use and AMD: Should You Stop Taking Aspirin?
Mass. Eye and Ear Advises Talking with Your Doctor First
Aspirin is commonly taken by patients to decrease risk of cardiovascular disease, including ischemic stroke and heart attack (myocardial infarction). It is one of the most widely used drugs worldwide. Some published studies, however, have reported a link between regular aspirin use and an increased risk of the “wet” form of advanced age-related macular degeneration (AMD); in light of these studies, some patients are concerned about their eye health and wondering if they should continue to take aspirin.
Dr. Ivana K. Kim, Co-Director of the AMD Center of Excellence of the Harvard Medical School Department of Ophthalmology and a physician on the Retina Service at Massachusetts Eye and Ear, recommends that patients talk with their doctors before making any changes in their aspirin regimen: “In general, I wouldn't advise stopping aspirin unless directed by a physician. Every patient’s medical status is unique, and the benefits of long-term aspirin use may far outweigh its risks," said Dr. Kim.
Evidence is Inconclusive
In a recent study published online by JAMA Internal Medicine on January 21, 2013 Australian researchers Gerald Liew and colleagues reported a higher risk of developing neovascular or “wet” AMD associated with regular aspirin use, defined as taking aspirin once or more per week. The typical dose of aspirin prescribed in Australia was reported to be 150 mg daily. The increased risk, however, appears small: only 9.3 percent of patients who took aspirin regularly were found to develop “wet” AMD after 15 years compared to 3.7 percent of non-users. This is roughly a 2-fold increase in risk.
Similar results were reported in the Beaver Dam Eye Study published in JAMA in December, 2012; eye researchers reported a risk of developing neovascular AMD after 10 years as 1 percent for aspirin users and 0.5 percent for nonusers.
Researchers did not find an association between regular aspirin use and advanced “dry” AMD.
“Any decision concerning whether to stop aspirin therapy is … complex and needs to be individualized,” according to Liew and colleagues, “Currently, there is insufficient evidence to recommend changing clinical practice…” (JAMA Internal Medicine, 2013).
Dr. Kim agrees with these guidelines, noting “Doctors need to assess each patient individually based on ocular findings and overall cardiovascular risk.”
About Age-related Macula Degeneration (AMD)
In developed nations, AMD is a leading cause of vision loss among people age 50 and older. Currently, about one in every five individuals aged 60 years or more has AMD.
AMD gradually destroys the macula, the part of the eye that provides sharp, central vision needed for seeing objects clearly, and patients with AMD gradually lose their central vision.
The dry form affects 90 percent of patients with AMD. Light-sensing cells in the macula slowly die off, gradually blurring central vision in the affected eye. There are no currently available treatments for advanced dry AMD. In “wet” AMD, new blood vessels under the macula leak blood and fluid, and can cause more sudden vision loss.. Various treatments are available, including medications injected into the eye and photodynamic therapy.
Risk factors for AMD in addition to age, include genetics, cigarette smoking, body mass index, and high blood pressure.