The message for the public is that healthy older people should not begin taking aspirin. 
 
 “If you don’t need it, don’t start it,” Dr. McNeil said. 
 
 But those who have already been using it regularly should not quit based on these findings, he said, recommending that they talk to their doctors first. 
 
 Dr. McNeil also emphasized that the new findings do not apply to people who have already had heart attacks or strokes, which usually involve blood clots. Those patients need aspirin, because it inhibits clotting. 
 
 The study, named Aspree, is important because it addresses the unanswered question of whether healthy older people should take aspirin, said Dr. Dr. Evan Hadley, director of the division of geriatrics and gerontology at the National Institute on Aging, which helped pay for the research. The National Cancer Institute, Monash University and the Australian government also paid. Bayer provided aspirin and placebos, but had no other role. 
 
 “For healthy older people, there’s still a good reason to talk to their doctors about what these findings mean for them individually,” Dr. Hadley said. “This is the average for a large group. A doctor can help sort out how it applies individually. It’s especially important for people already taking aspirin who are over 70. The study didn’t include many people who had been taking it, and doesn’t address the question of continuing versus stopping.” 
 
 The most widely used guidelines for using aspirin to prevent disease came out in 2016 from experts at the United States Preventive Services Task Force. They recommend the drug to prevent cardiovascular disease and colorectal cancer in many people aged 50 to 59 who have more than a 10 percent risk of having a heart attack or stroke during the next 10 years. (That risk, based on age, blood pressure, cholesterol and others factors, can be estimated with an online calculator from the American Heart Association and the American College of Cardiology.) 
 
 For people 60 to 69 with the same risk level, the guidelines say it should be an individual decision whether to take aspirin. 

 In a large clinical trial to determine the risks and benefits of daily low-dose aspirin in healthy older adults without previous cardiovascular events, aspirin did not prolong healthy, independent living (life free of dementia or persistent physical disability). Risk of dying from a range of causes, including cancer and heart disease, varied and will require further analysis and additional follow-up of study participants. These initial findings from the ASPirin in Reducing Events in the Elderly (ASPREE) trial, partially supported by the National Institutes of Health, were published online on September 16, 2018 in three papers in The New England Journal of Medicine. 
 
 ASPREE is an international, randomized, double-blind, placebo-controlled trial that enrolled 19,114 older people (16,703 in Australia and 2,411 in the United States). The study began in 2010 and enrolled participants aged 70 and older; 65 was the minimum age of entry for African-American and Hispanic individuals in the United States because of their higher risk for dementia and cardiovascular disease. At study enrollment, ASPREE participants could not have dementia or a physical disability and had to be free of medical conditions requiring aspirin use. They were followed for an average of 4.7 years to determine outcomes. 
 
 "Clinical guidelines note the benefits of aspirin for preventing heart attacks and strokes in persons with vascular conditions such as coronary artery disease," said NIA Director Richard J. Hodes, M.D. "The concern has been uncertainty about whether aspirin is beneficial for otherwise healthy older people without those conditions. This study shows why it is so important to conduct this type of research, so that we can gain a fuller picture of aspirin's benefits and risks among healthy older persons." 
 
 The team of scientists was led by John J. McNeil, M.B.B.S., Ph.D., head of the Department of Epidemiology and Preventive Health at Monash University, Melbourne, Australia, and Anne M. Murray, M.D., director of the Berman Center for Outcomes and Clinical Research at Hennepin Healthcare in Minneapolis. The research was supported in part by the National Institute on Aging (NIA) and the National Cancer Institute (NCI), both parts of the NIH. The Australian component of the study also received funding from the Australian National Health and Medical Research Council and Monash University. Aspirin and placebo were supplied by Bayer, which had no other involvement with the study. 
 
 In the total study population, treatment with 100 mg of low-dose aspirin per day did not affect survival free of dementia or disability. Among the people randomly assigned to take aspirin, 90.3 percent remained alive at the end of the treatment without persistent physical disability or dementia, compared with 90.5 percent of those taking a placebo. Rates of physical disability were similar, and rates of dementia were almost identical in both groups. 
 
 The group taking aspirin had an increased risk of death compared to the placebo group: 5.9 percent of participants taking aspirin and 5.2 percent taking placebo died during the study. This effect of aspirin has not been noted in previous studies; and caution is needed in interpreting this finding. The higher death rate in the aspirin-treated group was due primarily to a higher rate of cancer deaths. A small increase in new cancer cases was reported in the group taking aspirin but the difference could have been due to chance. 
 
 The researchers also analyzed the ASPREE results to determine whether cardiovascular events took place. They found that the rates for major cardiovascular events -- including coronary heart disease, nonfatal heart attacks, and fatal and nonfatal ischemic stroke -- were similar in the aspirin and the placebo groups. In the aspirin group, 448 people experienced cardiovascular events, compared with 474 people in the placebo group. 
 
 Significant bleeding -- a known risk of regular aspirin use -- was also measured. The investigators noted that aspirin was associated with a significantly increased risk of bleeding, primarily in the gastrointestinal tract and brain. Clinically significant bleeding -- hemorrhagic stroke, bleeding in the brain, gastrointestinal hemorrhages or hemorrhages at other sites that required transfusion or hospitalization -- occurred in 361 people (3.8 percent) on aspirin and in 265 (2.7 percent) taking the placebo. 
 
 As would be expected in an older adult population, cancer was a common cause of death, and 50 percent of the people who died in the trial had some type of cancer. Heart disease and stroke accounted for 19 percent of the deaths and major bleeding for 5 percent. 
 
 "The increase in cancer deaths in study participants in the aspirin group was surprising, given prior studies suggesting aspirin use improved cancer outcomes," said Leslie Ford, M.D., associate director for clinical research, NCI Division of Cancer Prevention. "Analysis of all the cancer-related data from the trial is under way and until we have additional data, these findings should be interpreted with caution." 
 
 "Continuing follow-up of the ASPREE participants is crucial, particularly since longer term effects on risks for outcomes such as cancer and dementia may differ from those during the study to date," said Evan Hadley, M.D., director of NIA's Division of Geriatrics and Clinical Gerontology. "These initial findings will help to clarify the role of aspirin in disease prevention for older adults, but much more needs to be learned. The ASPREE team is continuing to analyze the results of this study and has implemented plans for monitoring participants." 
 
 As these efforts continue, Hadley emphasized that older adults should follow the advice from their own physicians about daily aspirin use. It is important to note that the new findings do not apply to people with a proven indication for aspirin such as stroke, heart attack or other cardiovascular disease. In addition, the study did not address aspirin's effects in people younger than age 65. Also, since only 11 percent of participants had regularly taken low-dose aspirin prior to entering the study, the implications of ASPREE's findings need further investigation to determine whether healthy older people who have been regularly using aspirin for disease prevention should continue or discontinue use. 

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 By Linda Carroll 
 
 For decades, a daily dose of aspirin has been widely considered a way to protect healthy people from cardiovascular disease and even cancer. But a large international study finds that even at low doses, long-term use of aspirin may be harmful — without providing any benefit — for older people who have not already had a heart attack or stroke. 
 
 The new research reinforces the results of a study published in late August, which found that daily low-dose aspirin was too risky to be prescribed to patients at moderate risk of heart disease. In the August study and the new one, researchers found a significant risk of internal gastric bleeding caused by the medication, which thins the blood. Older patients experienced no health benefits from taking aspirin, according to the new report, published Sunday in the New England Journal of Medicine. 
 
 “We knew there would an increased risk of bleeding with aspirin, because there has always been," said study coauthor Dr. Anne Murray, a geriatrician and epidemiologist at the Hennepin Healthcare Research Institute and the University of Minnesota, Minneapolis. "But not only did it not decrease risk of disability or death, it did not decrease the risk of heart attack and stroke, and there was an increase in the rate of death." 
 
 "For healthy people 70 and older who don’t have a reason to be on aspirin, such as a previous heart attack or stroke, there was no discernible benefit." 
 
 The current guidelines recommend a daily aspirin for adults in their 50s who are at high risk of cardiovascular disease, with high blood pressure, high cholesterol or a history of smoking. The new study was designed to find out whether low-dose aspirin could prolong healthy, independent living in seniors who had not shown signs of heart disease. 
 
 "For healthy people 70 and older who don’t have a reason to be on aspirin, such as a previous heart attack or stroke, there was no discernible benefit," Murray told NBC News. 
 
 The trial followed 19,114 seniors — 2,411 from the U.S. and 16,703 Australians — for an average of 4.7 years. The minimum age was 70 for Caucasian participants and 65 for African-American and Hispanic volunteers, due to their higher risk of dementia and cardiovascular disease. 
 
 At the end of the trial, 90.3 percent of the aspirin-treated patients were still alive, compared with 90.5 percent of those who received placebos. Rates of physical disability and dementia were similar between the groups. The rates of coronary heart disease, heart attacks and strokes were also similar. 
 
 The big difference between the groups was in the rate of internal bleeding. Hemorrhagic stroke, bleeding in the brain, gastrointestinal bleeding and bleeding in other sites that required transfusion or hospitalization occurred in 361, or 3.8 percent, of participants in the aspirin-treated group and 265, or 2.7 percent, of those in the placebo group. 
 
 Rise in cancer risk? 
 
 There was also an increase in cancer deaths in the aspirin-treated group, which surprised the researchers. Previous studies have found that aspirin may be protective against certain kinds of cancer. 
 
 "There was a small increase in the number of deaths overall in the aspirin group, with the largest proportion of deaths due to cancer," said Murray. "It is possible pre-existing cancers may have interacted with the aspirin." 
 
 It may ultimately turn out that there are more benefits than risks in certain populations, said the study’s lead author, John McNeil, a professor of epidemiology at the School of Public Health and Preventive Medicine at Monash University in Melbourne, Australia. 
 
 “But we have not identified results that are strikingly different,” McNeil said in an email. Further research that may identify which groups would benefit from regular aspirin use is underway. 
 
 Dr. Erin Michos, a cardiologist, called the results "alarming," saying that aspirin should be prescribed only selectively. 
 
 Big changes have occurred in preventive medicine since the original aspirin research was done, Michos told NBC News in an email. Patients now get statins to lower cholesterol and anti-hypertensive medications to lower blood pressure. 
 
 “I think it is time we started to phase out the use of aspirin broadly for the purposes of prevention in individuals who have not had a heart attack or stroke," said Michos, director of preventive cardiology at the Ciccarone Center for the Prevention of Heart Disease at the Johns Hopkins School of Medicine. 
 
 Dr. Ravi Dave says aspirin may make sense for a small group of older healthy patients, even if they haven’t already had a heart attack or stroke, such as smokers. But for healthy patients who have not had a heart attack or stroke and who are not at high risk, “I would consider taking them off,” said Dave, director of interventional cardiology at the University of California, Los Angeles. 
 
 That’s a decision Dr. Mark Huffman plans to make in conversations with his patients. 
 
 “Some of them will say, ‘If it ain’t broke don’t fix it,’ ” predicted Huffman, an associate professor of preventive medicine at Northwestern University’s Feinberg School of Medicine and a cardiologist at Northwestern Medicine. “Others will say, ‘If the data suggest I might not have any benefit, I would like to take fewer pills.’ ”
– If you're one of the millions of US adults taking aspirin daily as a preventative measure, two new studies have bubble-bursting news: Doing so may not do any good—and could actually cause harm. Researchers in both studies found that even low-dose aspirin carries a risk of internal gastric bleeding, and the newer study also found that older patients who were not at high risk of cardiovascular disease saw no health benefits from taking aspirin daily. "We knew there would an increased risk of bleeding," a study co-author tells NBC News (aspirin is a blood thinner). "But not only did it not decrease risk of disability or death, it did not decrease the risk of heart attack and stroke, and there was an increase in the rate of death." Aspirin has been widely used in healthy older adults to protect against cardiovascular disease and cancer. But the new international study followed 19,114 seniors for an average of 4.7 years. It found similar survival rates as well as rates of disability, dementia, coronary heart disease, heart attacks, and strokes for the half taking 100mg of aspirin daily and the half taking a placebo. But internal bleeding (hemorrhagic stroke, bleeding in the brain, gastrointestinal bleeding, and other bleeding) was found in 3.8% of patients taking aspirin versus 2.7% of those taking a placebo. There was also a small increase in the number of cancer deaths in the aspirin-treated group, the New York Times reports. One cardiologist not involved with the study notes that in the time since the original research on aspirin was done, patients can now take other medications to lower cholesterol and blood pressure, and suggests it's time to "phase out" the broad use of preventative daily aspirin.