Out of curiosity, those of us who have af are told that without anti-coagulants we are five times more likely to have a stroke. Ergo, with anti-coagulants are we are on a level playing field with 'normal' folk?
anti-coagulants: Out of curiosity... - Atrial Fibrillati...
anti-coagulants
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Annaelizabeth
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Excellent question.
I was told by my GP that it is still possible to have a stroke whilst on Anticoagulation but the chances are very much reduced and it is very rare. I assumed that this meant the chances were less than a normal person. I wish now I specifically asked as my assumption maybe wrong.
BobDVolunteer
Five times what risk? If your risk is very low then five times not much is not much but if you have co morbidities then the risk is much higher. Hence we have the CHADSVASC system. Anticoagulation reduces this risk by quite a lot but does not completely eliminated it. Remember that it is an annual risk so in five years that risk multiplies year on year.
Figures for strokes in anticoagulated people are screwed by those who are on poorly controlled warfarin with out of range INR and I think NOACS are too new to have any meaningful long term data although we do seem to be told that several NOACS are safer than warfarin .
Anticoagulation reduces your risk of ischemic stroke and increases your risk of major bleeds including hemorrhagic stroke. So you need to evaluate your CHAD2VAS2 and HAS-BLED scores and then make an educated assessment. For some people, taking anticoagulation will increase their risk of death so is counter-indicated.
It's important to emphasize that people with AF do not have "5 times" the stroke risk in the general population. Stroke risk depends on CHAD2VAS2 score. I append a previous comment that I made to a related question, as follows:
For the benefits of warfarin, see: Singer, DE, et al. The net clinical benefit of warfarin anticoagulation in atrial fibrillation. Annals of Internal Medicine, Vol. 151, September 1, 2009, pp. 297-305.
The benefits depend on risk profile. For those with a CHAD2VAS2 score of 0, the statistical change in stroke risk is roughly zero. For those with a CHAD2VAS2 score of between 4-6, the reduction in risk is 2.2% per year (i.e., roughly 2 people in every 100 each year will benefit from taking warfarin). Such a benefit might sound trivial but becomes significant over 10 years.
For estimates of risks as a function of CHAD2VAS2 score, see the following article:
Stroke risk in atrial fibrillation: Do we anticoagulate CHADS2 or CHA2DS2-VASc 1, or higher? by Jonas Bjerring Olesen; Christian Torp-Pedersen, Current Controversies, 2015.
This article reviews recent studies of stroke risk and they consistently indicate that if you have a CHAD2VAS2 score of 0, stroke risk is roughly the same as for people without atrial fibrillation ("five times the risk" misrepresents existing research, but has been helpful as an attention-grabbing way to raise awareness about the stroke-AF link). No researcher has claimed such a high stroke risk among people with a low CHAD2VAS2 score (although you may hear inaccurate figures thrown around on forums and in flyers)
That's all to technical for me,
All I know is that if my INR figures are between 2 and 3
That's ok for me, but as we all know, certain foods and meds can quickly change those figures,
All good - the take-home message is that you need to see an EP and get a principled judgement on whether to take anticoagulation. The answer to your question is unfortunately "not necessarily" -
but also - your INR score by itself doesn't tell you what your risk of stroke is.
Some very technical answers here, which I am not knowledgeable enough to respond to. If you are in a-fib there is a risk (or greater risk than normal risk) that your blood will clot (its not a certainty) because there is a pooling of blood in the heart as not all blood is being pumped out. That clot will cause the stroke. The risk is obviously quite high and therefore blood thinners are necessary.
My cardiologist has told me there is a good chance I will go into a-fib permanently one day and his comment to me was 'we will cross that bridge when get there, but don't worry about it, as long as you are on blood thinners a-fib poses no risk'.
Yes interesting - and yet having AF is a risk of stroke independently of whether you actually experience episodes of AF. Researchers are trying to identify and understand the sources of this complex association
Yes I know that to be true but when I was recently in hospital and had to have warfarin antidote to stop bleeding, I was told by my E.P. and 2 pther cardiologists that as I was on flecanide and not fibrilating my risk of stroke was very low. At the time I was too low to query this but I wish I had now. My E.P. had just come from an international arrhythmia conference in New York so I kind of expect him to be up with the latest thinking but who knows ....
This research shows people with persistent AF are more likely to have a stroke than those with paroxysmal AF - even though the persistent AF group was more likely to be on anticoagulation. This suggests to me that "being in AF" is definitely a risk.
eurheartj.oxfordjournals.or...
Thanks. Yes I agree. We all have a risk but if you can keep in rhythm it is less. That makes sense but goes against research that seems to show that being on rhythm meds has no bearing on morbidity than rate control meds. Perhaps that is because the rhythm control meds bring their own risks. Ho hum, wheels within wheels and all that.....
I will not believe this until I see a paper from a reliable source confirming it. Recently there was an article about research on just taking an anti-coag when an AF episode starts. This totally contradicts your statement about there being a risk factor of a stroke when you may not be having AF episodes.
Yes I agree Alan - it's confusing with contradictory opinions. My take is that you are indeed at increased stroke risk during and for a couple of days following an AF episode - but stroke risk also appears to remain elevated for people with AF (relative to the non AF population) even in the absence of an episode. There are review papers that cite this evidence - for example, in the reputable journal "Stroke", e.g.,
stroke.ahajournals.org/cont...
I also read an interesting thesis on mechanisms of stroke in individuals with AF, which argues that there are several reasons people with AF get strokes. Blood stasis (pooling) is one obvious mechanism but others include: atrial mechanical remodelling (the heart functions differently as a consequence of many episodes of AF); Abnormal blood constituents; Abnormal vessel wall; inflammation, etc. The thesis can be dowloaded here
digital.library.adelaide.ed...
Thanks for that. Very technical but one thing I got from it is that you do not necessarily have to be showing (or have) AF to be at risk with some of these other factors. It makes one think one should be on anti-coags even if not showing AF symptoms.
For me, it depends on your CHAD2VAS2 score. If you have a score of zero, anticoagulation does little to nothing for stroke risk, and increases risk of major bleeds. If your score is higher and you're indicated for anticoagulation - then take it. Some on this forum advocate anticoagulation for people with AF even if you're not indicated for it. But to me, that is the wrong approach - better to follow the international guidelines - they are based on evidence, not fear.
Does atrial cardiopathy have symptoms? It would appear one could have this without necessarily having AF and the implication is that this also heightens your stroke risk. Is there a test or this? The article to me made it sound that there is all manner of things to do with your heart that increase your stroke risk, and you may not even have AF to be susceptible to it all!
Hmmm. Atrial cardiopathy means "disease of the atria" - so not very specific. Such "disease" could be cardiomyopathy - a disease of the heart *muscle* - or any other type of cardiac disease. So hard to comment. But it's a good question. Here is one reference in case it helps.
On re-reading this, my take on it is: There are various heart 'conditions' that carry a stroke risk that could be resultant in precipitating your AF. If that is the case, you still carry your increased stroke risk even when not having AF episodes. However, you are not necessarily going to get AF, but the risk of stroke is still heightened. However, you could get AF and not have the other heart 'conditions' and so not suffer the increased stroke risk that they permanently present. This seems to be going beyond AF on its own and taking in other peripheral heart activity as well. I wonder if these conditions show up on an echo. I felt the article was still speculating somewhat.
Unfortunately there is a lot of speculation and in many situations in the medical world that will remain so. A lot of medicine is an art and not a science or an engineering or construction project. The closest that we can get to running accurate tests is when you have identical twins (or the new Welsh triplets) and one twin develops an illness or condition that the other doesn't. I was told by a medical researcher that even when all the exhaustive sets have been done to lunch a new drug and it has been approved many new side effects come to the fore and also some of the known side effects significantly diminish.
My cardiologist asks me and others reluctant to take blood thinners, 'Do you want to die? You only need to be in AF for one second for a clot to form and cause a stroke'
Well, I was reluctant when Warfarin was suggested because I have relatives (admittedly not very close ones) who had brain bleeds. One was swiftly fatal. It is very unsettling if one usually finds oneself, when there's an 85% / 15% split, in the minority and all the more so if one is in the under 1% bracket more than once.
Three months after being in NSR after my first cardioversion in 2012 I stopped Warfarin due to joint pains. Back in AF 15 months later I took warfarin until three months after the next cardioversion.
This time I have been in AF from February 2015 but just elected to take Warfarin again this February as I will be having an ablation but mainly because I want either a Watchman device or an Amplatzer Amulet fitted to be rid of Warfarin for good.
I enquired about the Watchman but my EP does not offer it.
Very few do. I have been put forward for the Amplatzer Amulet trial at the Royal Sussex. Ten hospitals are conducting trials at the moment. If I don't get on it I'm willing to pay for it or the Watchman. Though it seems that the Amplatzer is slightly better.
I had some correspondence with London Bridge Hospital to be a private patient last year and they said that I was a suitable Watchman candidate subject to having a CT scan.
There are two other methods of removing the LAA being done by a surgeon at the Royal Sussex but NICE regards them as experimental and does not recommend them to patients.
I am still Stateside and have noticed recently on television an increasing amount of legal advertisements relating to the Watchman and ensuing medical problems. Given this is the States, but nevertheless obviously not all hunky-dory yet!
That would wake someone up ! and perhaps your own stroke risk is extremely high so this approach was called for. But for most people with AF - it's important to ignore any dramatic flapping of arms that some less informed doctors might engage in - we need to make educated decisions based on the best information we have, and using stroke risk profiles (CHAD2VAS2 score) based on massive data sets represent the very best information available. And crucially, you can also "die" from a major bleed as a consequence of taking anticoagulation (for some with AF, the risk of "death" from taking anticoagulation is higher than the risk of stroke from not taking it).
A neighbour and a friends brother each had massive stomach bleeds in the past year one on Warfarin the other on a NOAC but he had also been taking ibuprofen at the same time.
Remember,though, anticoagulants are NOT "blood thinners"
oops, my bad. I thought those were different names for the same thing.
They are Jonathan. It's just that some folk on here don't like the term 'blood thinners' as physically, anticoagulants don't change the blood's viscosity and therefore don't 'thin the blood'. But we all know what it means and that's all that matters.
Even NICE studies call them 'Blood Thinners'
I know, but they're really not. Our lovely bob volunteer has drilled it into me, before hearing his explanation, I thought they were the same too.
If NICE and many other medical journals, reports and trials call them thinners we should just go with the flow.
And just to throw some confusion into the debate, my EP has had me anti-coagulated for a decade with a CHADS score of 0, until I reached 65, so now it's 1. He is adamant it is right for me even though I have no other condition or history/family history of strokes/TIA's.
I did ask him about it, and my zero CHADS score, but he still said I was a lot better off on AG's.
But maybe that's just something to do with me. I did have very bad AF round the clock.
Koll
There will always be examples of research emerging that overstate the stroke risks associated with AF, just as there will be research that understates it. Like most things in life, the truth probably lies somewhere in the middle.
Certainly, when AF comes knocking, the first thing we are told is that we are at greater risk of stroke now than we were yesterday. If we have other health factors at play, as highlighted in CHAD2VAS2, these will further increase stroke risk. Mind you, they probably did yesterday, before our 'electrics' started playing up. As a result there will be early discussions about anti-coagulation. We know that the 'authorities' are prepared to pay not insignificant sums of money for us all, no matter what our CHAD scores are, to have anti-coagulation for the rest of our lives if we want it. In these days of competing fiscal priorities, they must know something! But of course you can refuse it, if you know better.......
I think we could all gain important 'knowledge' from a very simple published survey where all stroke survivors in a given year were checked for AF. It would be very illuminating to discover what percentage of stroke survivors in the last 12 months had AF. We can't know the figure for non-survivors of course though another piece of information we are given when diagnosed is that strokes caused by AF are generally less likely to be survivable. If that is true then the percentage found by checking the survivors is likely to be 'conservative'. Nevertheless, this information would be very helpful to us all.
But, there are too many folk who start their first post on this forum with:
"I had a stroke...... and was diagnosed with AF....".
So I think I'll keep taking the tablets.
There is some information and studies on the % of those who had strokes who were found to have AF I think that this was on the UK Stroke Association Website. Also see AFA website.
Yes. When I complained about having to go on warfarin at my very first meeting with the anticoag. nurse... she told me that I was fortunate as she had people come to her only diagnosed after they had had a stroke. That shut me up!
Hi Bob,all the NOAC`s have had extensive testing! They are relatively "New" in the UK because of the cost!
They have been prescribed in Europe and other parts of the world before we were introduced to them!
They are marketed as being much safer,as long as you follow the dosage of the drugs,and more reliable than Warfarin!
For those of us with artificial heart valves NOACs are contra indicated. My GP is as concerned for me taking warfarin as not due to high blood pressure, a history of stomach ulcers and being in my 80's.
Hi I was told by my EP my score was zero so just take aspirin I had AF but not permanent AF. I followed advise and went on to have a stroke 18 months ago, luckily I recovered well and now take rivaroxaban and have been told it is for life. I feel very fortunate to have recovered and would not feel happy not taking them now.
Rob
Strokes are not limited to people with AF. You may had one irrespective of whether you had AF or not.
Was your age below 65?
43
sorry, that wasn't for you!
The authorities are also prepared to pay not insignificant sums of money for nearly all of us to take statins whether we need them or not. Many people cry Big Pharma profits and refuse to take them not believing the dangers. When it comes to NOACs at many times the cost of Statins people do not say that and want them for their convenience and fear stroke risk much more than clogging arteries.
BobDVolunteer
I think that the one important thing to understand is that despite all the recent push for anticoagulation in AF UK is still about fourth from the bottom of the list of European countries when it comes to the percentage of at risk patients actually taking anticoagulants. It has been calculated that we could save at least 8000 stroke related deaths a year if this was changed.
It is also important to remember that the link between AF and stroke has only been paid any attention to since 2007. I can still recall the committee meeting I attended at BHF when stroke prevention was first mentioned rather than just treating Atrial Fibrillation.
I am well aware of some members dislike of large drug companies and the conspiracy theories they propound but to me it really comes down to one thing. Do I want to risk a stroke?
At the end of the day it comes down to the individual consultant (they have widely varying opinions) and the individual patient. You can never absolutely decide whether anticoagulation is 100% right or 100% wrong. Even though it is commonly quoted that it is 5 times the risk you could have a 0.1% risk and still have a stroke.
Someone could be on anticoagulation and still suffer a stroke.
Someone could have AF for some years and not suffer a stroke.
One thing that mustn't be overlooked is that many people with AF have other heart / circulation related issues and / or other health issues. These can affect whether or not anticoagulation is needed / or the type of anticoagulant.
Interestingly my Cardiac consultant told me a couple of weeks ago that I would have to stop warfarin for a procedure but that I would have to have heparin before and after as a bridging anticoagulant because the risks associated with stopping and starting warfarin needed to be minimised.
When I was working as a nurse in palliative care, I spent a lot of time explaining that statistics and research is very valuable to the health care provider in planning for and providing appropriate care, medication and treatment.
It is much less helpful to us as individuals as we are unable to know where on a bell curve an individual is situated. We may THINK we have an idea, but also optimism and pessimism play their part.
Research is very interesting but differentiating between good and bad research trials is very difficult even for the experts let alone us enthusiastic amateurs.
For me, the choice is easy - I'm told I'm at risk of a potentially damaging stroke because of my AF, so I will take the 'risk' of anticoagulation. Whether that gives me the same risk factor as 'ordinary folk' doesn't matter. There are so many other variables that cause risk - BP, diet, lifestyle, genetics - that it's not easy to compare.
Research into AF stroke must still be in its infancy as I think it's only in the last 10 years or so that the two factors were related in medical thinking. There are bound to be conflicting views and conclusions until enough reliable data has been collected and analysed.
It's a tightrope, really. Will we carry on or fall one side or the other?
I am a patient rep. and I have been involved with the preparation of the new NICE Anticoagulant Patient Decision Aid for people with AF. The percentage risk was discussed at the last meeting and the medical representatives said that studies had only run for a year and it was unknown whether the risk over five or ten years remained the same, or culmulative, or exponential. Nor was there a differentiation between active people in good health and those who were inactive, over weight with high blood pressure and lipids.
As an example of percentage risk, in 2013 I was walking around with three hernias including a hidden femoral hernia found in less than 1% of men and a candidate for immediate emergency surgery if it had been diagnosed. In 2014 I was close to death from a rare reaction to dronedarone and amiodarone that I understand has an occurance of 0.06% (pulmonary toxicity / cryptogenic organising pneumonia). I'm back in the gym without anticoagulants and unmedicated for AF. Intense exercise usually kicks off AF and I'll average 160 bpm peaking at over 200 bpm. That might be stupid but what percentage risk is that?
If we know that certain factors, and there are many whether it be af or others, increase the risk of clotting and therefore stroke, taking an anti-coagulant seems to be an obvious choice for some. However, the dilemma comes when it is down to the personal choice of the individual concerned as to whether he or she takes that option and goes with medical opinion or against it. Personally, I would go with it.
The risk is actually not "5 times". The 5 times comes from comparing people generally with those with AF without taking into account risk factors. People with AF generally have a lot more risk factors.
If you do take risk factors into account then the added risk from AF is as follows:
Chads 0: 77%
Chads 1-2: 75%
Chads 3-4: 47%
Chads 5-6: 37%
See this study for more detail: ncbi.nlm.nih.gov/pubmed/258...
What this shows is that the CHADS score for stroke risk applies also to people who do not have AF. In fact AF is just another risk factor for stroke - perhaps equivalent to an added 4 on the CHADS score.
If 4 were added to the CHAD score for AF then everyone with AF would automatically be on anti-coags regardless of age. Wonder what source you got that figure from.
No, you would adjust the threshold to say 5 before people went on OACs. That way people with high risk factors but no AF would also have to be on OACs. If you read the article I quote it mentions: "This observation implies that future studies may be warranted to investigate the effect of prophylactic anticoagulation in high risk non-AF patients."
AF is just another risk factor among many. I estimate 4 as about right given the increase in risk produced by AF. That would make someone with AF and no other risk factors about the same as someone without AF but who is female over 75 with high blood pressure.
I think it reduces the risk by about 60%- obviously it depends on what other risk factors an individual has for stroke- one good thing is , my GP pointed out we are at less risk of DVT when flying as anti-coagulated!!
another point of interest- the reason age comes into Chads Vasc is the change in heart tissue as we get older- our last Cardiology speaker likened this to a baby's skin and then our roughened skin as we get older !! This allows a surface where the slow moving blood, while we are in AF, is more likely to clot. Possibly this might explain why we are told we are more at risk if we have af even if not in AF?? Or could just be that coming in and out of AF increase the risk of expelling any clots in the Atrial appendage rather than gentle permanent af?? Just speculating here !! However, it seems logical to think we are at much less risk between episodes of AF if they are some time apart.
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