Atrial fibrillation

Atrial fibrillation, stroke risk and blood thinning medication

People with atrial fibrillation (AF) are at increased risk of stroke. The likelihood of stroke increases five times among those with AF, with 12,500 strokes directly attributable to AF occurring annually (National Institute for Health and Care Excellence June 2014). Here we look at the increased risk of stroke for people with atrial fibrillation (AF), explore people’s experiences of stroke and Transient Ischaemic Attack (TIA or minor stroke) and consider how anticoagulants (blood thinning medications) such as warfarin can reduce the possibility of having a stroke. We also explain why aspirin is no longer recommended as a blood thinner for people with AF.
 
Atrial fibrillation and stroke risk
We asked Dr Tim Holt, an academic GP to talk about the increased risk of stroke for people with AF.

Dr Tim Holt explains how having AF can increase a person’s risk of stroke.

Dr Tim Holt explains how having AF can increase a person’s risk of stroke.

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I think the risk that we worry the most about is the risk of having a stroke, which is significantly higher in people with atrial fibrillation compared with otherwise similar people who don’t have that condition. So if you have atrial fibrillation then the risk of having a stroke in the future is perhaps five or six times higher than if you didn’t have atrial fibrillation. So this is a particularly important condition to detect because there’s a lot of things that can be done to reduce that risk of stroke.

Have you seen any patients who’ve had AF related strokes?

Yes and sometimes this happens to people who are known to have AF and they have a stroke despite the condition already having been diagnosed. In other situations, the AF might be diagnosed when they’re admitted to hospital with a stroke and in other patients, a stroke occurs without there being any evidence, at that time, of AF but then in the future, the person is found to have AF, which is coming and going and was probably responsible for the initial stroke.
The consequences of having a stroke can be devastating. (For more see our website on Stroke).

James did not know he had AF until he had a stroke, aged 59. He described his memories of the stroke and its impact on his life.

James did not know he had AF until he had a stroke, aged 59. He described his memories of the stroke and its impact on his life.

Age at interview: 63
Sex: Male
Age at diagnosis: 59
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Well, I, yes, had a stroke before I realised I had AF. On Saturday lunchtime, I believe it was, and I went upstairs to get changed to go and do some work in the garden, and I collapsed in a heap. I managed to attract Jenny and Jenny realised what had happened and called an ambulance and hey ho to hospital. I was fairly confused. I’ve vague memories of going into hospital and quite alarmed to hear I’d had a stroke. We struggled on. I came through and then it was realised I had AF and we weren’t sure what AF was and looked it up on the internet and found out.

And everything was just an uphill struggle I suppose. I used to bounce a ball against the wall and catch it, stuff like that, because my coordination went all to pot and I tried playing golf again. I couldn’t even hit the ball off the tee and my right and my left hand went totally out of sync with each other [laughs]. But I’ve never been a brilliant golfer but it was really disappointing, but what else? What was the what was the question? I’ve forgotten what the question was.
We also spoke with a number of people who had experienced a Transient Ischaemic Attack (TIA or minor stroke) caused by a temporary lack of blood to part of the brain. (For more see our website on TIA and minor stroke). They described symptoms similar to stroke, including dizziness, numbness, slurred speech and detachment. Chris Y noticed his arm was ‘getting a bit numb’ and his speech was ‘gobbledy gook’ for 10-15 seconds after coming back from jogging. Unlike a full stroke, TIA/minor stroke episodes are usually resolved after a short time. They can however, increase the risk of possible further TIAs or a full stroke. As George X was told by a paramedic when he had a TIA, “Let that be a warning to you, old fellow. It’s a precursor to a main stroke.”

Keith had a TIA/minor stroke after driving back from Bath. His speech was slurred and he felt detached from his surroundings.

Keith had a TIA/minor stroke after driving back from Bath. His speech was slurred and he felt detached from his surroundings.

Age at interview: 61
Sex: Male
Age at diagnosis: 57
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I’d driven back from near Bath and felt perfectly good. Went into to my house and we got back safely and I just turned to talk to my wife and couldn’t, I was slurring speech. I couldn’t speak clearly so I stood up and looked to my left and a window seemed to veer to the left and change colour [laughs]. But again, it was it was a strange feeling in that I felt detached from it, not any pain at all, just slightly detached from where I was and so I sat down at the other end of, I moved to the other end of the sofa and sat down and then gradually, very gradually, speech began to return bit by bit and by that time, the ambulance came and I was away. But when I got feedback from that it was it was it was, I was told that there’d been a blood clot and in in one of the vessels in my heart and that had pumped up to the brain and that’s what caused it and I’d been extremely lucky that the effects had been so slight.

George X experienced two TIAs/minor strokes; the first 8 years ago, the second 4 years ago. He described the symptoms of his first TIA.

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George X experienced two TIAs/minor strokes; the first 8 years ago, the second 4 years ago. He described the symptoms of his first TIA.

Age at interview: 78
Sex: Male
Age at diagnosis: 63
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I had it, my first one in the June I think it was, June July time. That was eight years ago, June, that’s it and this doctor, lady that’s passed, absolutely brilliant. I had it on the Monday night, I’d been out for a little walk with [wife] because she can’t walk much and it was such a lovely day. No problems. Came back, sat in the settee, [wife] went and made a cup of tea about half past six, I was watching Central News. No pain or anything. I was then going to make a pot of tea. She said, “The kettle’s boiling if you’re going to make the tea.” She’s in that doorway, “Are you messing about? Are you messing me about?” And I can’t move, I’m paralysed all down my left side.” So the emergency chappy came out from [town] at eight o’clock that night and [laughs] by then I could talk again. My speech had come back.

Maggie found it ‘very, very frightening’ being on her own when she experienced a lot of dizziness, minor seizures and a lack of feeling on one side shortly after her second ablation.

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Maggie found it ‘very, very frightening’ being on her own when she experienced a lot of dizziness, minor seizures and a lack of feeling on one side shortly after her second ablation.

Age at interview: 70
Sex: Female
Age at diagnosis: 61
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After the second ablation, when I got up from the chair and fell over, I had no feeling on one side, that I then thought I was having a stroke or a transient ischemic. TIA. But again, [sighs] I’m on my own. You’re never, never that close to anyone, you know, that you’re in a household where you can call out to a husband or wife or a partner or a son or a daughter. So most of the things I experienced, I experienced on my own. I didn’t ever think I was ever going to have a stroke at that point, I was very, very scared. I took the phone, I just sat here, the room was going round and round and I thought, “I’ll just put my finger on nine before I would actually pass out completely then I can lift the receiver and do nine nine nine, they find you.” And that’s the worst I’ve been of it all I think. Many times I’ve sat here and just gone very dizzy, but I get better and I sit up again and I’m okay. But that, I think was very, very frightening, particularly I had no feeling on that one side.
An early diagnosis of AF and appropriate treatment may reduce the risk of stroke and TIA/minor stroke. People spoke of missed opportunities for diagnosis which, in retrospect, they felt could have minimised the risk.

James’ wife Jenny said that they had never heard of AF before her husband’s stroke. She feels that they now have to live with thoughts of ‘what if’.

James’ wife Jenny said that they had never heard of AF before her husband’s stroke. She feels that they now have to live with thoughts of ‘what if’.

Age at interview: 55
Sex: Female
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So the big thing is, your big, that you have to live with is, if only. If only we’d booked a doctor’s, if only we’d even gone onto the internet and put in irregular heartbeat, that information would have been there, enough information would have been there to have gone to the doctor, who’d have put you on an anti-coagulant or put James on warfarin, and there’s every chance that stroke would never have happened. He’d have had AF but he wouldn’t have had the double whammy of a stroke on top of an irregular heartbeat. 

Chris Y had symptoms of paroxysmal AF for ten years, but it was only after his TIA/minor stroke that AF was caught on an ECG and diagnosed.

Chris Y had symptoms of paroxysmal AF for ten years, but it was only after his TIA/minor stroke that AF was caught on an ECG and diagnosed.

Age at interview: 64
Sex: Male
Age at diagnosis: 62
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And it wasn’t until I had the, after I’d had the TIA and I was I was on aspirin and I had that headache, and I went into A and E, that was the first time they’d actually got a recording of it. So it had just been, you know, sort of bad luck I suppose in some ways. But I mean I was, I never had any sort of reassurance or any or anything from anyone. I was, you know, I just didn’t get the feedback that I was sort of, not expecting but I thought, “Well, obviously there’s nothing wrong”, when perhaps there was. And one interesting thing that came out, when they did the MRI scan, the consultant picked up that I’d had several TIAs. They could see they could see it on the on the scan that I’d had, probably not as severe as I’d had that day in in March 2010 when I had, when I had when I had the TIA, but I’d obviously had some minor ones before. So if I’d had an MRI scan perhaps a bit earlier, that could have been picked up and I was, you know, more, you know, it was a greater possibility that I might have, you know, something that could have been medicated, if you like, earlier on. 
People we interviewed were aware of the increased risk of stroke as a result of having AF, and some people worried about this. Paul, who was asymptomatic (had no symptoms of AF), said that having a stroke was his ‘biggest fear’, while George Y was keen to avoid anything that might bring on a stroke which he regarded as ‘the most debilitating, sudden, life changing disabilities that anyone could be given’. Ginny, who had worked with elderly people who had had a stroke, said ‘You don’t want a stroke, I can tell you that.’ George X, who has had two TIAs (minor strokes), worried about having a major stroke. He said: ‘I tell you now I’d end it there and then. I’d finish it.’ Some said that they would have had their symptoms investigated sooner if they had realised they were at increased risk of stroke.

Aware of her increased risk of stroke, Ginny decided to have an ablation to keep her heart in check.

Aware of her increased risk of stroke, Ginny decided to have an ablation to keep her heart in check.

Age at interview: 49
Sex: Female
Age at diagnosis: 45
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But you see, if you don’t take beta-blockers and your heart is not kept in check, you’ve got more likelihood of getting a stroke through having atrial fibrillation. Atrial fibrillation, don’t think for a minute that I’ve just had an ablation because I want to go and rush up and down a mountain. The older you get, the longer you have atrial fibrillation the more likely you are to end up with a stroke. You are a higher candidate in a higher risk category for having a stroke. So there is a very good medical reason for giving people ablations. It’s not just so they can go, like me, and go and run up and down some mountain. It is a serious, atrial fibrillation is a serious condition and can lead to stroke.

Marianne fears she will have a stroke in the future, although this may not happen. She fears being permanently disabled.

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Marianne fears she will have a stroke in the future, although this may not happen. She fears being permanently disabled.

Age at interview: 72
Sex: Female
Age at diagnosis: 54
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Oh, I shall have a stroke presumably, and I don’t know how bad, assuming the ablation is not effective. A junior doctor once said to me, I said, “What’s the worst that can happen?” “Oh, you could have a stroke.” He said, “But it wouldn’t be a really bad one. You probably wouldn’t die.” I said, “You mean I’d just be permanently disabled?” I thought that it probably might be better to die. Yeah, I shall have a stroke I assume, and who knows? I don’t know. That’s the end result I guess, probably. I don’t know, maybe a pacemaker would stop that, but I’ve no idea. Haven’t got into that part yet.
(*For more on ablation see ‘Medical procedures and interventions for atrial fibrillation’)

Stroke risk and blood thinning medication (anticoagulants)
Desire to avoid a stroke is an important focus for people with AF. Anticoagulants (medicines which thin the blood) can be effective in stroke prevention and are recommended as a treatment for AF for those people with a moderate-high risk of stroke. Anticoagulants include warfarin and the newer medications dabigatran, rivaroxaban, and apixaban. (For more see ‘Alternatives to warfarin for atrial fibrillation: the new anticoagulants'). Yet despite the benefits of taking anticoagulants to reduce stroke risk, only 45% of those who are eligible for these treatments currently receive them (National Institute for Health and Care Excellence June 2014).

Dr Tim Holt explains how anticoagulants can help reduce the risk of stroke and suggests reasons why people might be reluctant to take them.

Dr Tim Holt explains how anticoagulants can help reduce the risk of stroke and suggests reasons why people might be reluctant to take them.

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The risk of having a stroke, in people with atrial fibrillation, is significantly greater than people who don’t have that condition but, fortunately, that risk can be reduced very, very substantially by taking blood thinning medication, anticoagulants. However, there’s often a reluctance to use anticoagulants. Sometimes that reluctance comes from the patients, sometimes it comes from the doctor or sometimes it just comes from both through an anxiety over the thinning of the blood, the increased risk of bleeding, particularly in more vulnerable older people, who may be at risk of falls.

And which drug, in particular, are we talking about?

Well, any of the anticoagulants can raise the risk of bleeding but I think there is more concern over the usual drug, which is warfarin, particularly because that drug requires regular monitoring of blood levels to ensure that the dose remains appropriate for the individual. Because the dose is different for each individual, it varies between individuals and also varies from time to time within the same individual, so it’s important that it’s monitored. Of course, that’s an inconvenience to the patient because they have to have regular blood tests and they have to also comply with certain advice over their diet and other medications may interact with these drugs, which also influences the risk of somebody having a problem such as bleeding.
Among the people we spoke to, decisions about whether or not to take anticoagulants were often closely linked to attitudes to stroke risk. Some were positive about their need for treatment. Pauline said that she would be too afraid to stop taking the medication that her cardiologist had prescribed, while Jo did not mind being on warfarin because it was ‘keeping me alive and preventing a stroke’. David Y trusted his consultant and took his advice to start on warfarin. Eileen, whose mother and aunt had had strokes, was ‘only too pleased’ to be on warfarin to reduce her stroke risk.

After his TIA, Keith reluctantly accepted the need for warfarin rather than aspirin.

After his TIA, Keith reluctantly accepted the need for warfarin rather than aspirin.

Age at interview: 61
Sex: Male
Age at diagnosis: 57
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I had to go onto warfarin, well, following that I had six weeks, I couldn’t go to work for six weeks, which was very frustrating because my speech had come back by then and I felt good and I was advised to go out and get as much exercise as possible, which I tried to. Then of course, I was on blood thinners then, warfarin, aspirin wasn’t deemed strong enough so I went onto warfarin then. And I, and I really dislike that. I don’t know why. Again it’s more tablets really. Again it’s another admission that things aren’t fully a-okay but. 

Tell me what it’s meant for you being on warfarin.

It means I bruise more easily and I bleed more easily and I have to remember to take the wretched things. Again, it’s an admission of weakness I think, you know, there’s a there’s a, I’d much rather be without it.

Brendan has had little difficulty adjusting to warfarin. He explained the purpose of anticoagulants.

Brendan has had little difficulty adjusting to warfarin. He explained the purpose of anticoagulants.

Age at interview: 59
Sex: Male
Age at diagnosis: 57
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Well, I mean basically, in the, as I understand it and my science may be a bit wrong [laughs] but because of the fibrillation, the aorta does not necessarily empty itself of all of it, so there’s a possibility there might be an occurrence there might be a danger of a clot forming. So in order to prevent that, the blood is kept at a thinner level, which is what the warfarin does, and it’s between an INR of two and three I think is my, is the range that I have to stay within. I probably had been aware of warfarin before in the sense that one of my friends experienced AF, and she had resisted warfarin for a long time but, eventually, agreed to go on it. So I knew kind of what it was about, and I’m very lucky in the sense that I didn’t have any difficulty in adjusting to it either.

Dot was both relieved and worried when it was explained that her stroke risk was constant, whether she had occasional or persistent episodes.

Dot was both relieved and worried when it was explained that her stroke risk was constant, whether she had occasional or persistent episodes.

Age at interview: 64
Sex: Female
Age at diagnosis: 55
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I wasn’t ever concerned before this summer because when I was having a lot of AF before I was diagnosed, I didn’t know I was having AF and I was at risk of stroke, so I was blissfully unaware. And this summer when I was blissfully aware that there was a stroke risk, I was quite worried because I was having it so often, and I was under the mistaken impression that it was when you were having the AF that you threw off clots. And I think somebody told me afterwards, you can throw off a clot at any time. So I was I was ignorant even then. So I was worried just because of having it so much, but that was partly my ignorance because I thought it was, didn’t realise I was at risk of a stroke all the time and had been for the last ten years.
Others, however, were unsure whether warfarin was appropriate for them, or, after considering their circumstances, decided not to take it. George X found that taking warfarin made him go ‘as red as a beetroot’ and his doctors took him straight off it. Martin felt that stroke risk was assessed and anticoagulants prescribed without attention to individual circumstances or preferences. He called this ‘medicine by numerology.’

Mary, who was reluctantly taking warfarin, wondered whether her risk of stroke warranted taking medication.

Mary, who was reluctantly taking warfarin, wondered whether her risk of stroke warranted taking medication.

Age at interview: 84
Sex: Female
Age at diagnosis: 84
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I don’t know why they put me on warfarin. I know that I don’t I didn’t think that atrial fibrillation and warfarin, I mean warfarin won’t do anything for atrial fibrillation I don’t think. It’s more for avoid a stroke obviously, but am I likely to get a stroke because I’ve got atrial fibrillation and I haven’t taken it for a long time anyway. I haven’t had any more instances or. I just wish I knew more.

Elisabeth Y explained why she refuses to take warfarin.

Elisabeth Y explained why she refuses to take warfarin.

Age at interview: 69
Sex: Female
Age at diagnosis: 63
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From day one I was badgered to take warfarin and we were just about to go round Iceland you see and I said, “I’m not taking it anyhow but.” I said, “I’m certainly not going to bleed all the way round Iceland.” You know how empty the island is.

And I said, “Look, I’ll sign an affidavit. I’ll put a letter in your case notes that I refused it.” I said, “If I had an artificial heart valve I’d accept it very willingly.” And when you think, six and a half years, I’ve not had a stroke. Touch wood. And, I’m not really superstitious, that’s just a way of behaving. And when I think of all the blood tests weekly that I’ve avoided and all the bottles of pills that I’ve avoided.

The point is they don’t understand who I am. I’m me and I have certain knowledge including, I have girlfriends running to the GPs once a week and being and having their fingers pricked and then some people have these things that they can test themselves. I mean what a carry on. It’s not a life to my mind.
At times the decision to go off warfarin was made after successful surgery to treat AF. This depended, however, on individual attitudes to risk.

Following a successful ablation procedure, Chris X decided not to carry on taking warfarin.

Following a successful ablation procedure, Chris X decided not to carry on taking warfarin.

Age at interview: 65
Sex: Male
Age at diagnosis: 50
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I am aware that it’s not necessarily a particularly nice thing to be on. It can cause, there are a number of side effects you are much more liable to bleed easily. It can cause things like gum bleeding and it can cause problems in your intestine as well. It has to be very tightly monitored in terms of whether it’s going to be any good or not. Most people do that with a weekly visit to the GP and well, for instance, going to this, I went to Europe AF this year a few months ago. There was [specialist name], who is a, the world, almost world expert on anti-coagulation and he said, you know, he was using the terms, “Well, you know, if I don’t really like a patient, then the first thing I’ll do is put them on warfarin.” [Laughs]. Because it’s just not a nice thing to be on.

Bob decided to continue taking warfarin despite a successful ablation.

Bob decided to continue taking warfarin despite a successful ablation.

Age at interview: 66
Sex: Male
Age at diagnosis: 59
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I chose to continue taking warfarin because I consider that just because I don’t have AF now, doesn’t mean that it doesn’t still contribute a risk, and there is some evidence that having had atrial fibrillation, it can create changes within inside the atria, that the scarring that’s created by this constantly writhing rather than pumping rhythmically, can create a situation where the surface area can make the blood flow more slowly, and it could still contribute to clotting. So since warfarin causes me no problems, I mean I work on the engines, I work in the garden, I do I cut myself, okay, I might leak for a bit but I stick a plaster on and it stops. And I’m on such a regular dose, my INR varies so little, I only get checked about every three months now because every time I go it’s just where it was before. So it causes me no problem, so why take the additional risk of possibly having a stroke when it’s not causing me a problem. And it, to me, it’s that simple.
Some people reported being confused by the advice given by health professionals. They felt they were sometimes given contradictory messages leaving them unsure whether to take warfarin or not.

Paul stopped taking warfarin after 9 months. His doctor told him he did not fit into the higher risk bracket for stroke.

Paul stopped taking warfarin after 9 months. His doctor told him he did not fit into the higher risk bracket for stroke.

Age at interview: 57
Sex: Male
Age at diagnosis: 55
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The only thing I do fear for is from a stroke point of view. So I may well decide to move back onto warfarin as a precaution more than anything else because, you know, whilst I’m not too disabled from the AF, I think a stroke would be much more disabling than the AF for me at the moment. So I may well go back to that I think.

It was again, it it’s one of the recommendations that the doctor, the doctor said, “Well, you don’t fit into the higher risk bracket.” And as I was saying, the higher risk is normally deemed by somebody who is on normally, a very high blood pressure and or over sixty five. So I don’t actually meet that and, although my heart rate my blood pressure is slightly raised, not sufficiently enough for him, in his opinion, to move me onto the warfarin. Although he did give me that option, if I so wished to go back onto the warfarin, and the associated properly, you know, associated things that go with it like the regular blood tests and restricting your intake of different food stuffs and things like that.

A consultant Bob met at a conference told him that some GPs are afraid to prescribe warfarin because of the risk of internal bleeding. Bob believes you have to make up your own mind.

A consultant Bob met at a conference told him that some GPs are afraid to prescribe warfarin because of the risk of internal bleeding. Bob believes you have to make up your own mind.

Age at interview: 66
Sex: Male
Age at diagnosis: 59
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There is a chap, who I’ve heard at various conferences, and who I have met not on a social level but at conferences and had long conversations with. Again, for professional reasons, I won’t give you his name but he is the top man on anti-coagulation and stroke risk in the country, in my opinion, and he is always been of the opinion that most GPs are more frightened of prescribing warfarin than the patients are of taking it, because one of the risks of warfarin is internal bleeding. 

So you have to balance the risk of a gastro-intestinal bleed against the risk of an ischaemic stroke, where a blood clot gets into your brain and knocks out half your brain. Now, the reality is that there is less risk than doctors consider, and I think it’s probably true that if a doctor has had a patient who’s had a gastro-intestinal bleed and been rushed to hospital, he’s less likely to prescribe warfarin for the next two or three months, but if he had a patient who’d had a stroke he wouldn’t be more likely to prescribe warfarin. So one has to take an educated look at it and make your own mind up.

Carin spoke of contradictory messages which influenced her decision not to take warfarin.

Carin spoke of contradictory messages which influenced her decision not to take warfarin.

Age at interview: 62
Sex: Female
Age at diagnosis: 55
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So I thought about it, the risk that he had given me, otherwise I’m healthy so my risk was quite low but I, nevertheless, decided to go on anticoagulants because of what he’d said. And so I went, I then happened to have a visit with the endocrinologist, who said to me, “Oh, oh you need to, there’s a big risk of stroke. You need to go, you really need to go on it as soon as.” And so okay, I got the ball rolling. I went to see the haematologist, who basically said, “No, don’t go on it.” But nobody says, “Yes” or “No.” You know, you have to work it out for yourself, what you’re going to do. So nobody gives you like, everybody is contradicting, you know, it’s you have to like fight for yourself in the end.

So I’m still not on that because of the haematologist, I trusted the haematologist to be right. He did not say, “Don’t go on it.” But I could read in between the lines that he said, “Don’t go on it, as per yet, as per now.” So I’m on aspirin and hope for the best.
(For more see ‘What is it like being on warfarin for atrial fibrillation?’)

Aspirin as a blood thinning medication? Current advice
When we interviewed people in 2012 aspirin was still considered a useful treatment to protect people with atrial fibrillation (AF) from strokes by thinning the blood. Some people we spoke to preferred taking aspirin to warfarin. For them aspirin was believed to be a simple alternative that needed no monitoring and promised fewer side effects. Yet while aspirin was widely used, some people expressed concern. Aspirin was not risk-free and could increase the risk of bleeding. Elisabeth Y experienced nose bleeds and bleeding after dental surgery. Some doubted whether aspirin was effective enough to prevent strokes. Noel spoke to doctors at an AF conference who were surprised that he was taking aspirin rather than warfarin. They told him that ‘aspirin has little or no effect on people with AF’, which, at the time, contradicted his consultant’s advice to ‘stay on aspirin’. Eileen preferred warfarin as an anticoagulant, believing that while aspirin was ‘good for heart attack victims’ it was not a sufficient anticoagulant for AF patients.

Maggie assumed aspirin was safe until she had a gastrointestinal bleed. She no longer takes any form of blood thinning medication.

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Maggie assumed aspirin was safe until she had a gastrointestinal bleed. She no longer takes any form of blood thinning medication.

Age at interview: 70
Sex: Female
Age at diagnosis: 61
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I assumed aspirin to be safe. With warfarin, patients are monitored and there’s a little bit more control and everyone is aware that they’re actually taking warfarin but with aspirin you plod on, and I was on maybe five years, aspirin and last year I had a small gynae op, for which I was taken off my aspirin, I was taken off all medication for the procedure and then told afterwards I could go back on. I went back onto my aspirin on the Friday. By Tuesday of the next week, I’d had an intestinal bleed, which they put down to the aspirin.

My follow-up then was to go back to my cardiologist and review my medications as well. He said, “You seem to have been on the aspirin long enough. Let’s try you without an anticoagulant.” 

I just said, “Fine, then you don’t think I need it.” He said, “No, I think it’s long enough now that you don’t need an anticoagulant and we’ll see you next, during next year and we’ll put a tape on and see how you are.” 

Roger’s cardiologist took him off warfarin and put him on aspirin which had fewer side effects. However, after having a TIA/minor stroke, Roger was put back on warfarin.

Roger’s cardiologist took him off warfarin and put him on aspirin which had fewer side effects. However, after having a TIA/minor stroke, Roger was put back on warfarin.

Age at interview: 60
Sex: Male
Age at diagnosis: 50
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He said about it for probably for about six months to a year, “We can probably take you off warfarin and put you onto aspirin. It would be better for you than warfarin because of the potential side effects.” Although I must be honest, the only side effects I tended to get from warfarin was if I got any scratches from gardening, they tended to come up as heavy bruises, and in the summer I tend to wear long sleeve shirts because people wondered what on earth I’d been up to with these great big bruises on my arm but really, it wasn’t an issue for me to take warfarin. It was his decision really to take me off. I wasn’t pushing for it. 

Then I had my TIA. Then he put me back on it again. Whether I should have been taken off it in the first place is questionable I think because ironically, a friend of mine, who’s also got the atrial fib, he was taken off it by the same cardiologist. He had a TIA and was put back on it since then. Maybe there’s something more than just a pattern there. We were both if you like, downgraded from warfarin to aspirin, and then we both returned to warfarin.
Since the interviews, new guidelines on AF have been published by the National Institute for Health and Care Excellence (NICE) (CG180 June 2014). The guidelines state that doctors should not offer aspirin as a single drug for stroke prevention to people with atrial fibrillation. Evidence suggests that warfarin and the newer anticoagulants such as dabigatran, rivaroxaban or apixaban are much more effective than aspirin at preventing strokes. (For more see ‘Alternatives to warfarin for atrial fibrillation: the new anticoagulants’).

Dr Tim Holt explains why aspirin is no longer considered effective in reducing stroke risk in people with atrial fibrillation.

Dr Tim Holt explains why aspirin is no longer considered effective in reducing stroke risk in people with atrial fibrillation.

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It used to be advised that if a person either couldn’t take warfarin because it was considered for some reason unsafe or they simply declined it, then aspirin was considered to be a reasonable alternative, although it was always recognised that it wasn’t as effective as warfarin. However, more recently, it’s been discovered that, in fact, it’s not only much, much less effective and not really effective at all in reducing the stroke risk in people with atrial fibrillation, but it’s actually not that much safer than taking warfarin either, provided the warfarin can be safely and carefully managed and monitored. So aspirin as an alternative to warfarin is no longer considered a reasonable approach. It’s not as effective. It’s not really significantly effective at reducing stroke risk and it’s not completely safe either. It’s, you know, it can cause haemorrhages. It can cause internal bleeding and it can cause bleeding into the brain. So it’s now advised that people should be assessed over what their stroke risk is, people with atrial fibrillation, should be assessed over whether they are at risk of stroke and this applies to the majority of people with atrial fibrillation, they should be offered an anticoagulant, taking into account their bleeding risk. There are people in whom the risk of bleeding is too high and they shouldn’t be offered anticoagulants but the majority of people can have their stroke risk reduced substantially by taking an anticoagulant and these people should not be given aspirin in that situation.

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