(NaturalNews) People who take aspirin regularly to reduce their risk of heart attacks and strokes are significantly more likely to suffer from age-related macular degeneration (AMD), the primary cause of blindness in the elderly. These are the findings of a study conducted by researchers from the University of Sydney and published in the journal JAMA Internal Medicine.
The study was funded by the National Health & Medical Research Council Australia.
AMD is characterized by the gradual destruction of the macula, the central portion of the eye that is responsible for seeing objects clearly. It typically affects people aged 50 and older. AMD occurs in two primary forms: "dry" (or "geographic atrophy"), characterized by the gradual breakdown of macular cells and a resulting blurring of central vision, and "wet" (or "neovascular"), characterized by the leakage of blood and fluid into the macula from the blood vessels beneath. Only about 10 percent of AMD cases are wet, but those cases are much more severe.
Many people take aspirin daily in order to prevent cardiovascular symptoms such as heart attacks and strokes, because the drug is a potent blood thinner. Yet many studies have shown that regular aspirin use significantly increases the risk of both cerebral and gastrointestinal bleeding.
"Our present study now raises the possibility that the risk of neovascular [AMD] may also need to be considered," the researchers wrote.
Risk more than doubled
Follow-up on a recent study suggesting that a daily aspirin may increase the risk of wet AMD, the researchers analyzed data on 2,389 people over the age of 48 who were taking part in the Blue Mountains Eye Study. At the start of the study, all participants were questioned about AMD risk factors, aspirin use, and cardiovascular disease status. Every five years, they underwent retinal examinations for AMD. A total of 257 participants, or 10.8 percent, were classified as regular aspirin users, defined as taking one or more aspirin per week over the course of the past year.
The researchers found that regular aspiring users were 2.37 times as likely as non-regular users to develop wet AMD during the 15-year study period. Specifically, only 0.8 percent of non-regular aspirin users had developed wet AMD after five years, compared with 1.9 percent of the regular users. The rates were 1.6 percent and seven percent at 10 years, and 3.7 percent and 9.3 percent at 15 years for non-regular and regular users, respectively.
"Regular aspirin use was significantly associated with an increased incidence of neovascular AMD," the researchers concluded. This effect remained strong even after the researchers adjusted for other potential AMD risk factors including age, gender, smoking history, body mass index, systolic blood pressure, and a history of cardiovascular disease.
No connection was found between aspirin use and dry AMD rates.
According to the National Eye Institute, the best way to reduce your risk of AMD is to avoid smoking, get regular exercise, eat a balanced diet high in fish and green leafy vegetables, and maintain healthy blood pressure and cholesterol levels.