Aspirin versus eye health; new data

Long-term aspirin use may slightly raise the risk of developing age-related macular degeneration, a leading cause of blindness among the elderly, a new study suggests.

An estimated 19 percent of U.S. adults report using aspirin regularly, often for its heart-protective benefits, and its use increases with age. Incidence of age-related macular degeneration also rises in older age, making this association important to examine, the study authors said. About 1.8 million Americans currently have the eye disease, which destroys sharp, central vision.

The study found that the potential risk is small but statistically significant "and needs to be balanced with the significant morbidity and mortality of undertreated cardiovascular disease," said study senior researcher Jie Jin Wang, a senior research fellow at the Center for Vision Research at the University of Sydney.

Also, "the increased risk of age-related macular degeneration was only detected after 10 or 15 years, suggesting cumulative dosage of aspirin may be important," Wang said. Although aspirin is among the most effective cardiovascular disease preventives, regular use over the long term has been associated with adverse side effects, Wang added. Study results regarding aspirin's link to macular degeneration have been inconsistent to date.

In the study the researchers collected data on more than 2,300 people. Regular aspirin use was defined as once or more a week. As part of the study, the participants had four eye exams over 15 years. Almost 11 percent of patients used aspirin regularly. After 15 years, about 25 percent of the aspirin users developed what is called neovascular age-related macular degeneration; the most severe form referred to as the wet form that leads to blindness. The cumulative rate was about 9 percent among aspirin users compared to less than 4 percent among non-aspirin users.

A different recent study, published in the Dec. 19 edition of the Journal of the American Medical Association, also found that regular aspirin use for at least 10 years slightly raises the risk of developing age-related macular degeneration. An expert, Dr. Sanjay Kaul, director of the Vascular Physiology and Thrombosis Research Laboratory at Cedars-Sinai Medical Center in Los Angeles, said for patients, the evidence supporting use of aspirin to prevent a second heart attack or stroke is "indisputable". For preventing a first heart attack or stroke, the evidence of aspirin's benefits isn't clear and the decision of whether to take it should be based on individual risk and patient history, he noted.

People who take aspirin regularly for pain might consider switching to another painkiller to avoid possible side effects, which also include bleeding, Dr Kaul added. "Heart attacks have a high risk of death, so the question is: Is it worth the possible increase in [risk for] age-related macular degeneration, compared to the risk of getting a heart attack?" said lead researcher Dr. Barbara Klein, of the University of Wisconsin School of Medicine and Public Health. Klein said the data from her study does not suggest that people should stop taking aspirin for preventing heart attack. The report is published Jan. 21 in the online edition of the journal JAMA Internal Medicine.