AUDIE CORNISH, HOST:
A big, new study found the risks of taking a low-dose aspirin every day outweighs the benefits. This is for otherwise healthy older people. What about the rest of us? NPR health correspondent Rob Stein joins us now to talk about it. Welcome to the studio, Rob.
ROB STEIN, BYLINE: Hi.
CORNISH: What exactly did researchers actually look at, and then what did they find?
STEIN: Yeah, so this study looked at a very specific group, as you mentioned, otherwise healthy older people. And what I mean by that specifically is African-Americans and Hispanics ages 65 and older and Caucasians ages 70 and older. And the study looked at more than 19,000 of these older folks in the United States and in Australia who took either a low-dose aspirin every day or a placebo. And after about five years on average, the researchers found no evidence that taking aspirin actually helped. It didn't protect against dementia or any other disabling health problems. So that was a big surprise.
CORNISH: What are the risks, though?
STEIN: So the risks of taking aspirin are actually pretty well-known. It can increase the risk for serious, sometimes even life-threatening bleeding. And that's what they found in this study - that people who took the aspirin were more likely to experience bleeding. That wasn't a surprise. What was a surprise is that there was actually a hint that the people who took aspirin were - overall were more likely to die apparently - looked like from cancer. Now, the researchers really don't know what to make of that. It could have been a fluke, so they have to do more research to really figure out what's going on with that.
CORNISH: OK, so what about people hearing this thinking that, OK, basically no one should take aspirin every day?
STEIN: Right. No, there is really good evidence for some people to take a daily low-dose aspirin. And those people are - people who've already had a heart attack or stroke should take it - an aspirin - a low-dose aspirin everyday to reduce the risk of having another heart attack or stroke.
And now after that, it gets a little complicated. There's a group known as the U.S. Preventive Services Task Force, and what they recommend is anyone in their 50s who has at least a 10 percent elevated risk of having a heart attack or stroke - like, they have high blood pressure or high cholesterol - they should take a daily aspirin to reduce the risk of having a heart attack or stroke in the first place. And anyone in their 60s who are at increased risk for a heart attack or stroke - they should talk to their doctor because they might benefit from taking a low-dose aspirin every day, too.
CORNISH: Any other caveats?
STEIN: Yeah. The caveat is that, as I mentioned - that, you know, aspirin can cause bleeding. So anybody who is at risk for bleeding should really think twice in those groups about taking aspirin 'cause it could be dangerous. And they should only take aspirin if they have a life expectancy of at least 10 years and are - and think they can take it for 10 years because that's how long it takes to get the benefits.
STEIN: Can we go back to the bit about cancer, which is the other thing that aspirin can supposedly do?
STEIN: Yeah, yeah, so that's kind of confusing, too, because this study found that people might be at greater risk of dying from cancer. But there is a lot of good evidence that taking low-dose aspirin every day can reduce the risk for colorectal cancer. So the researchers who did this study - they're planning to follow the people in the study for longer to see if that benefit shows up. It might just take more time. And the - there's other research going on to see if taking a daily aspirin might have other benefits from aspirin, maybe helping to treat breast cancer and prostate cancer, for example.
CORNISH: That's NPR health correspondent Rob Stein. Thank you for explaining it.
STEIN: Oh, sure. Nice to be here. Transcript provided by NPR, Copyright NPR.