There was a big development in health care news this week. The buzz is all about the latest guidelines on aspirin since our friends at the US Preventive Services Task Force updated the recommendations. It came out in the Annals of Internal Medicine just this week on April 12, 2016. Talk about “hot off the presses” reporting, eh? This post is going to decipher the guidelines on who should take a daily aspirin to prevent heart attacks, stroke, and now even colon cancer. I think this is one of the most important topics I’ve covered yet.
Consider the humble aspirin
- Descendant of willow bark
- Invented during the reign of Queen Victoria
- Known to doctors and nerdy people (that may be redundant) as acetylsalicylic acid (aka ASA to prescription-writers)
- Introduced by Bayer in 1899 as a powder to treat rheumatic conditions like gout
- Has been used for centuries (maybe without knowing why) as a pain reliever
- Almost certainly reduces risk of heart attacks , strokes, and colon cancer. Possibly reduces risks of esophageal, breast, ovarian, and maybe some other cancers as well.
Should I take an aspirin?
I should note that I’m going to stick to people who have NOT had a heart attack or stroke. Those people certainly need some kind of anti-platelet treatment and aspirin is one of the best choices for many reasons and may be helpful for secondary prevention of future problems. Here we are referring to primary prevention which means trying to prevent heart attack and stroke (and we can add colorectal cancer) in people who have never had these conditions.
So let’s get to it. What do the new guidelines say?
These people should consider taking a low-dose aspirin (81 mg) every day
- AGE: Age 50 – 59
- INCREASED RISK: At least 10% risk of having a stroke or heart attack in the next decade
- LIFE EXPECTANCY: At least 10-year life expectancy
- LOW BLEEDING RISK: Not at increased risk of internal bleeding
- WILLINGNESS TO STICK WITH IT: Willing to take a daily low-dose (81 mg) aspirin every day for 10 years
Seems rather limited, right? After all, over 40 percent Americans over age 50 currently take a daily aspirin. Now it seems that many of them don’t need to.
Let’s look at why each of these five criteria are important:
Criteria 1: Age
People age 50-59: The strongest benefit to daily aspirin are those in their 50s. Huh? Aren’t they a bit young?
The rationale for this age recommendation is because the main drawback to taking an aspirin is bleeding. The bleeding we most worry about with aspirin users is in the gastrointestinal tract — your digestive or GI system. As it happens, the risk of bleeding rises as we age. In fact, although the risk of heart attack and stroke rises as we age, the risk of bleeding rises even faster. Thus the person most likely to get the biggest benefit with the lowest risk are at the younger end of the age range. So the guidelines say 50-59.
For people age 60-69: The guidelines recognize that people in their 60s may still benefit from the heart attack and stroke-lowering potential of aspirin. So if you are in this age group and your risk of bleeding is low (you don’t have ulcers, for instance), then you should talk to your doctor and make an individual decision on whether to take a daily aspirin. Basically a judgment call.
For people younger than age 50 or older than age 69: The guidelines do not recommend daily aspirin use for these groups. The risk of bleeding very likely is greater than the benefit of risk reduction in the older age group (remember, risk of bleeding rises even faster than does risk of heart attack and stroke for older people).
Also remember what I said earlier, we are talking about people who have NOT had a previous heart attack or stroke. If you had one of those already, this doesn’t apply to you.
OK, we covered age. What’s the deal about 10% risk over the next decade?
Criteria 2: High risk people
Even if you are in the age 50-69, aspirin may not be right for you. The people who are most likely to benefit are those at highest risk for heart disease and stroke. Remember, aspirin use is all about risk-vs-benefit. The higher the chances you have of having a stroke or heart attack the more benefit you may receive. In other words the benefit of aspirin may outweigh the risk in some people.
So the guidelines want us to calculate our risk of having a stroke or heart attack in the next 10 years, and if our risk of that happening is 10% or greater, than aspirin may make sense for us.
OK, quick, what is your 10 year risk?
You don’t know? I didn’t think so – neither do I!
But it is an informative exercise to do and there are calculators out there to help you. Here is a risk-calculator from the American College of Cardiology. Click the link and get your risk percentage. You do need to know a few numbers like your blood pressure and cholesterol to do the calculator.
So if your risk of having a heart attack or stroke is at least 10% and you are 50-59 years old (and maybe if you are 60-69), then you meet the first two criteria.
On to the next one:
Criteria 3: Life expectancy
I won’t say much about this one other than to say that if you have other medical conditions that are likely to limit your lifespan, you are not likely to get much of the benefit of daily aspirin. That’s because the benefit is really for people who take it for many years (see the next criteria). If you are battling a tough cancer, for instance, maybe you don’t need to worry about the aspirin.
Criteria 4: Low bleeding risk
Remember this is all about balancing benefit (reducing chance of heart attack and/or stroke) with risk (usually this means bleeding). This is the risk:benefit ratio that doctors are endlessly worrying about even if we don’t admit it.
If you have a history of bleeding in your stomach or intestines (for instance, an old ulcer or gastritis or something like that), then the risk of daily aspirin probably outweighs the benefit. There are lots of reasons people are at a higher bleeding risk: taking anti-inflammatory drugs (like ibuprofen or steroids), heavy alcohol use, liver disease, to name just a few. It is precisely because of this bleeding risk that we always say “Talk to your doctor to see if aspirin if right for you” – good advice.
Criteria 5: Willingness to stick with it
This is my paraphrasing of the criteria; the smart people at the US Preventive Services Task Force didn’t say “willingness to stick with it” but that’s really what they mean.
This gets back to the idea that those that seemed to get the most benefit from daily aspirin were those who took it regularly for at least 10 years. Taking it sporadically or for shorter periods of time doesn’t seem to help much. You really need to commit to trying to take it every day and do so for at least a decade. The benefit dwindles if you don’t.
What about colon cancer?
This is a really intriguing part about the new aspirin guidelines. If you search around the Internet, you are going to find oodles of studies and opinions and recommendations and half-baked ideas that aspirin can prevent darn-near everything. Well, there is actually some solid scientific evidence that a daily aspirin, when taken for a long time (there’s that ten-year recommendation again), probably does reduce the risk of colorectal (colon and rectal) cancer. This is powerful new stuff indeed!
In addition to the emerging evidence on risk reduction for colorectal cancer, there is some pretty good, though less convincing, data that daily aspirin use may reduce the risk of some other types of cancers – esophageal, breast, prostate, and so forth. I have to stress that it may reduce the risk. This is not strongly proven.
One more comment on cancer risk reduction
I’m not sure what to tell people about this new stuff about reducing cancer risk by taking an aspirin a day. What I am finding to be the most commonly held advice in the medical community is: if you should take a daily aspirin anyway for stroke and heart attack risk reduction, then consider the reduced risk of colon cancer as an added benefit. Sort of like icing on the cake.
But if you are not among the people for whom a daily aspirin is recommended for heart attack and stroke risk (see the criteria above), then it is probably not a good idea to take aspirin solely for the cancer benefit.
The proverbial jury is out on that last point I must admit.
Women are from Venus, Men are from Mars
Talk about torturing the planetary metaphor . . .
One last interesting point about the aspirin guidelines. It seems that for women, aspirin is best at reducing the risk of stroke. For men, aspirin is better at reducing heart attack risk.
Take that information for what it’s worth, I guess.
Dr. Hilden’s 3 favorite drugs
I have often had this little mental list of 3 drugs that I feel have enormous impact in our lives. When I prescribe them, I feel like they are doing what they are supposed to do which I guess is a pretty good measure of success. Aspirin is one of them.
I’ll let you guess what the other two are. In fact, leave me a comment in the section below with your guesses for my other two favorite drugs.
For now, here’s to the humble aspirin.