Daily aspirin will not reduce the risk of death or heart attacks in healthy older people, but it will increase the risk of internal bleeding, according to a leading Australian-American study.
The historical study involving more than 19,000 people over 70 has shown that taking a low dose (100 mg) of aspirin every day will not prolong life or prevent disability, despite the fact that the pill helps older people healthy to live longer.
Three articles published Monday in the New England Journal of Medicine revealed the result of a seven-year study that could lead to a rethinking of global guidelines related to the use of aspirin to prevent common conditions associated with aging.
The trial did not include people who take aspirin for medical reasons as recommended by their doctor, including those who have already had a heart attack or stroke.
Instead, he focused on answering the question of whether the medication reduced the risk of healthy seniors suffering their first heart attack or stroke, or losing their good health.
The lead author, Professor John McNeil, says the results are clear: "If you do not need it, do not take it."
The randomized double-blind trial, called ASPREE, was conducted by Monash University in Australia and the Berman Center for Clinical Research and Results in the United States.
Using the help of general practitioners, the researchers recruited 16,703 older people in Australia and 2411 in the United States, with approximately 9500 people in the aspirin group and the placebo group.
The participants took a low dose of aspirin daily for almost five years, and the researchers controlled their health and any onset of illness, disability or death.
They found an increase in the number of cases of severe internal bleeding among consumers of aspirin (3.8 percent) compared to the placebo group (2.8 percent).
"There was more hemorrhage, especially in the stomach and upper gastrointestinal tract," Professor McNeil told AAP.
The study also showed slightly higher rates of death in those taking aspirin, mainly cancer, although the results were not statistically significant, he said.
The "tentative finding" required more research as researchers in other studies suggest that aspirin can prevent cancer, he said.
Professor McNeil cautioned that the findings did not apply to those with existing conditions where aspirin is recommended as a preventive measure against future heart attacks, strokes or angina.
He said that anyone with questions should follow the advice of their doctor.
The APREE trial was funded by the US National Institutes of Health. UU., The National Council of Health and Medicine of Australia, the Cancer Agency of Victoria and the University of Monash.