Rethinking aspirin's role in preventing strokes, heart attacks

[00:00:00] Host Amber Smith: From Upstate Medical University in Syracuse, New York, I'm Amber Smith. This is "HealthLink on Air." For many years, many patients have taken an aspirin a day to prevent heart disease or stroke, but recently a group of doctors on the U.S. Preventive Services Task Force proposed recommendations that might change this practice. Here to tell us more about this is Dr. Debanik Chaudhuri. He's an assistant professor of medicine, and he's the division chief of cardiology at Upstate. Dr. Chaudhuri, thank you for making time in your schedule to talk about this.

[00:00:32] Debanik Chaudhuri, MD: Thank you for inviting me for this interview.

[00:00:36] Host Amber Smith: Now, many doctors have advised their patients, once they reach a certain age, to take an aspirin a day. And before we get into the new recommendations, I'd like to ask, why did that become sort of a rule that people would take aspirin once they reached a certain age? What does the aspirin do?

[00:00:53] Debanik Chaudhuri, MD: Oh, that's a great question. I think we'll have to trace our way back a little bit to the history of aspirin and how it came about. As you know, aspirin in a unrefined form has been used for thousands of years, and then eventually towards the end of the 19th century, human beings were able to synthesize aspirin outside of willow bark for the first time. And at that time it was used as an antipyretic. The anti-platelet action was first noticed in the 1950s by, actually, a family physician on the West Coast, I believe. And in the 1960s, the anti-platelet activity for aspirin was first brought into focus. Now, after the initial clinical trials, in the 1980s for acute myocardial infarction, there was a huge interest in aspirin because it clearly showed an improvement in survival in patients who were on aspirin, as opposed to who were not. So that is where the interest in using aspirin as a tool for primary prevention of cardiovascular disease started. And it was thought that since aspirin does such a great job of keeping people alive after they have had a heart attack, it just stands to reason that if you have coronary heart disease and haven't had a previous heart attack, and as you age over a period of time, like you were more and more likely to have those sort of blockages that are not maybe symptomatic. It was thought that having an aspirin will prevent a heart attack and ,hence, keep people alive for longer. I think that was the rationale at that time. And there are some primary prevention trials which did bear it out, to a certain extent.

[00:02:39] Host Amber Smith: So aspirin is something you said it's been around thousands of years. It started out to treat pain, right? As a pain reliever? .

[00:02:47] Debanik Chaudhuri, MD: Pain and fever.

[00:02:48] Host Amber Smith: And then fever. The antipyretic is (to relieve) fever. How long ago was it that we learned that it would thin the blood?

[00:02:56] Debanik Chaudhuri, MD: Oh, actually, this was noticed in the 1950s. So actually, I believe the name of the gentleman was Dr. (Craven). He was out of the West Coast. And he noticed that if people took a lot of aspirin for pain relief, they ended up having some bleeding episodes. So he surmised that giving aspirin for specifically that purpose might reduce their cardiovascular events like prevent myocardial infarction (heart attack). He reportedly treated about 6,000 office patients with essentially chewing gum -- aspirin contained in a chewing gum. But in the 1950s, his initial observations were kind of ignored, and the approach died with him. And then it was revived in the 1960s, where some new laboratory methods were discovered and people saw that when blood treated with aspirin was loaded, more light went through, which means that platelets were not clumped. So that's how there was a resurgence in interest in aspirin's action on platelets.

[00:04:08] Host Amber Smith: Interesting. Well, let's get into these new recommendations. What is the U.S. Preventive Services Task Force, and why do doctors listen to this group's recommendations?

[00:04:19] Debanik Chaudhuri, MD: So the U.S. Preventive Services Task Force is a group of volunteers. I think there are 12 or 14 people on that panel. These are leaders in their field. They volunteered their time to be on the U.S. Preventive Services Task Force for four years. And their job is to, the way they define it is that they look for evidence gaps and knowledge gaps in the way we treat patients in various fields of medical sciences. And they look for those gaps and try to fill those gaps by recommending or directing of, research, writing guidelines essentially also informing the Congress regarding which segments of health care need to be funded for further research, essentially ensuring that the health care money that is being spent -- which is obviously astronomical -- is utilized for the appropriate purposes with the highest return on that investment.

[00:05:20] Host Amber Smith: So is it likely that the FDA, the Food and Drug Administration, and other groups like American College of Cardiologists, is it likely that they're going to agree with new recommendations from this task force?

[00:05:32] Debanik Chaudhuri, MD: Broadly, yes. Obviously, all these specific organizations will have their own nuances, but, yeah, broadly they do tend to agree with the USPSTF recommendations.

[00:05:45] Host Amber Smith: I know the actual recommendations are yet to be finalized, but just based on the proposed recommendations, as a cardiologist, leading a department of your peers at Upstate, what do you think are the most important changes?

[00:05:57] Debanik Chaudhuri, MD: I think the biggest change, that the USPSTF is going to accomplish, is to make the recommendations for aspirin more contemporary. The recommendation of taking up an aspirin game from older clinical trials, which were done in the eighties and early two thousands. And at that time, the therapy for cardiovascular disease was not as robust as we have now. We have statins, we have ACE inhibitors, we have beta blockers, and they are more widely used. So now the newer clinical trials in the last 10 years or so that have come up, they have tried to answer the question of whether aspirin is still relevant within the context of more advanced therapy, from the point of view of primary prevention-- not from the point of view of secondary prevention-- where aspirin is clearly indicated as of today. No doubt.

[00:07:01] Host Amber Smith: Who are the patients that are likely not going to be advised to still take a daily aspirin?

[00:07:08] Debanik Chaudhuri, MD: So let's start with the ones who are actually considered to be at a very high risk for cardiovascular disease. So let's say diabetes. These patients with diabetes were looked at in recent clinical trials. And if I can just name it, it's called the ASCEND study. And, in absence of established cardiovascular disease, they did not have any benefit with a preventive therapy with aspirin either. So these are the patients that would be excluded. So unless you had some sort of a demonstration either by an event or by imaging that you have presence of plaques within the vascular tree somewhere, that pretty much excludes everybody else from aspirin as a primary preventive therapy for a cardiovascular event.

[00:07:58] Host Amber Smith: Secondary prevention would be someone who's already had a heart attack or stroke --

[00:08:03] Debanik Chaudhuri, MD: Exactly.

[00:08:04] Host Amber Smith: -- and they would still be probably recommended?

[00:08:07] Debanik Chaudhuri, MD: Absolutely. And just to also clarify, like when we say primary prevention, such as those who have not had cardiovascular disease, there are like certain modalities of imaging, which if (they) demonstrate presence of plaques, which are a marker for atherosclerotic plaque, the kind of disease that causes heart attack or stroke, that is still considered cardiovascular disease. So let's say you do a carotid study, and you show that there is a plaque in the carotid artery, that qualifies as cardiovascular disease. And then you do recommend aspirin in such patients. If you do a calcium score for the coronaries, and you see that there is a high calcium burden, which parallels presence of plaque in the coronary vascular tree, that qualifies as cardiovascular disease, even though these patients may not have had a heart attack or a stroke. So those modifiers are definitely available.

[00:09:06] Host Amber Smith: So it sounds like a lot of people are still going to be taking aspirin as a preventive?

[00:09:11] Debanik Chaudhuri, MD: It's quite possible, especially if the less commonly used modalities, such as a coronary calcium score or carotid study, a duplex study that demonstrates presence of plaques, which are a harbinger of future events. They would probably still benefit from aspirin.

[00:09:28] Debanik Chaudhuri, MD: Now do the recommendations address the different dosages because some people take a baby aspirin (81 milligrams), so to speak, and some people take larger doses. Does that matter?

[00:09:38] Debanik Chaudhuri, MD: In terms of secondary prevention in patients who already have established cardiovascular disease, this question has been answered, to the effect that 81 milligrams of aspirin is just as effective; also, recent trials that looked at this particular question tried to answer this question, and the answer was that both were equally effective, and in at least in the more recent trial, it showed that the bleeding risks were not any more with 325 milligrams than with the 81. So yeah, I guess they're equivalent. So if 81 milligrams is enough and at least there is some data to suggest that it causes less bleeding, from older studies, it may be just safe to go straight to 81, if you have to continue to take it.

[00:10:22] Host Amber Smith: You're listening to Upstate's "HealthLink on Air." I'm your host, Amber Smith talking with the chief of cardiology at Upstate, Dr. Debanik Chaudhuri, about the use of aspirin as a preventive for heart attack or stroke.

[00:10:34] Host Amber Smith: So let me ask you about the patients who are no longer likely to be advised to take daily aspirin. These are people that were taking it as a primary preventive. In other words, they didn't have a history of heart attack or stroke, but there was some reason that maybe they would be at risk for it, so they were taking the aspirin to prevent something that might happen. Is that right?

[00:10:58] Debanik Chaudhuri, MD: Correct. Yes, that's correct. And most of these patients were recommended on the basis of an estimation of their 10-year risk. So previously it was recommended that if your 10-year risk exceeds 10%, then it may be a good idea to consider aspirin. Whereas in light of current data, even in diabetes patients, specifically diabetes patients with no established cardiovascular disease, and even in those groups of patients, it really did not show any benefit. I mean, there was clearly a reduction in ischemic events, and by that, I mean, having ischemic stroke, or heart attacks. But the benefits were essentially countered by the increase in bleeding. So overall it did not show any benefit. So that has to be taken into account that we forget that aspirin does come with a small, but substantial risk of bleeding, also.

[00:11:59] Host Amber Smith: So I'm sure you would say that patients who have been taking aspirin should definitely check with their doctor first, but in general, if someone is now advised not to take it, is it safe to just stop cold turkey, or do you need to taper off of aspirin?

[00:12:13] Debanik Chaudhuri, MD: Anytime you discontinue an anti-platelet medication, there is a short period of slight uptick in the body's ability to form thrombus (blood clots). (blood clots.) But when patients are on a small dose of aspirin, once you stop it, it just kind of gradually fades away, so it can potentially stop right away.

[00:12:35] Host Amber Smith: Is there something that a person should replace the aspirin with? Is there another medication or something that they should consider?

[00:12:43] Debanik Chaudhuri, MD: As off now there is no such recommendation. I think they should focus on a primary prevention in terms of their risk factors. Let's say diabetes or hypertension, and the focus should be on controlling those risk factors.

[00:12:56] Host Amber Smith: Well, I'd like to ask you about some other ways to prevent heart disease aside from aspirin and aside from medication, because I imagine recommendations maybe vary depending on each individual patient, but in general what sorts of preventative steps do you find yourself advising patients to take?

[00:13:14] Debanik Chaudhuri, MD: Well, as you know, in both, SHEA (Society for Healthcare Epidemiology of America) (Society for Healthcare Epidemiology of America) guidelines and also in U.S. Preventive Service Task Force recommendations, lifestyle modification plays a central role, you know, diet, exercise, and also how one conducts oneself in general interaction. I mean, we know that if you are a type A personality, like angry and constantly in conflict, it does increase the risk of a heart attack or stroke significantly, like at least over 20%, that we know of. On the other hand, if you're a type D personality where you have low self-esteem and conflict averse, but you are constantly having some difficulty of adjustment within, that is even more significant in terms of causing future cardiovascular events. So, you know, all those things, mental health, behavioral health, of all of those things come together. If you have anxiety, your risk of a heart attack goes up by more like 30%. I think in addition to the lifestyle modification and diet, I think a significant stress has to be put on mental health as well.

[00:14:27] Host Amber Smith: Have you reviewed the results of a recent study, it was in a journal of the European Society of Cardiology, and it seemed to indicate that going to sleep between 10 and 11:00 p.m. would help lower a person's risk of developing heart disease. So I wonder what impact sleep might have?

[00:14:45] Debanik Chaudhuri, MD: That essentially tells you that you should stop binge watching the Netflix. There is a clear signal from clinical trials that heart attacks tend to happen early in the morning. Sudden cardiac death also tends to happen early in the morning. There are studies on platelet reactivity, even when patients are on certain anti-platelet agents, which show that platelets are stickier between 5 a.m. and 10 a.m. than at other times, especially on certain medications. So there is a circadian diurnal variation of people's predisposition, predeliction , you know, vulnerability to heart attacks, if you will. And one of the things on that same study, what the author suggested was that if you're sleeping late, you're also waking up late. And the early morning sun is supposed to be one that resets the circadian clock, and you're missing that. So that clock is perennially disturbed, and that may have some impact on the way physiology reacts to that. But it certainly stands to reason that like many of us, you know, we are checking phones while going to sleep. All those things are disruptive for sleep and certainly adds to the mental stress. I can only imagine if somebody is a social media buff and are looking for the likes at 10 p.m., and if the likes don't come through, they would be stressed.

[00:16:14] Host Amber Smith: Right. Well, it seems like there's probably room for more research on circadian rhythms. But, also on aspirin, even though it's been around, it seems like forever, it seems like maybe there's still a lot to learn about how it works, right?

[00:16:27] Debanik Chaudhuri, MD: Certainly. We know that it blocks a certain enzyme that form certain hormonal factors that both dilate as well as constrict blood vessels, the cyclo-oxygenase pathways. But aspirin also has some other effects in the, some of the clinical trials, especially when followed for a long time. So we do not know everything about aspirin action by itself. And one thing we know for sure that there is clearly a benefit in terms of reducing heart attacks or strokes. It's just that if we could divorce its predisposition to cause bleeding from its ability to prevent stroke and heart attack, that would be potentially another game changer.

[00:17:11] Host Amber Smith: Well, I appreciate you taking the time for this talk, Dr. Chaudhuri. My guest has been Dr. Debanik Chaudhuri. He's the chief of cardiology at Upstate.

[00:17:19] Host Amber Smith: I'm Amber Smith for Upstate's "HealthLink on Air."