Deans' stroke musings: Aspirin should not be used for stroke prevention in AF patients

Changing stroke rehab and research worldwide now.Time is Brain! trillions and trillions of neurons that DIE each day because there are NO effective hyperacute therapies besides tPA(only 12% effective). I have 523 posts on hyperacute therapy, enough for researchers to spend decades proving them out. These are my personal ideas and blog on stroke rehabilitation and stroke research. Do not attempt any of these without checking with your medical provider. Unless you join me in agitating, when you need these therapies they won't be there.

What this blog is for:

My blog is not to help survivors recover, it is to have the 10 million yearly stroke survivors light fires underneath their doctors, stroke hospitals and stroke researchers to get stroke solved. 100% recovery. The stroke medical world is completely failing at that goal, they don't even have it as a goal. Shortly after getting out of the hospital and getting NO information on the process or protocols of stroke rehabilitation and recovery I started searching on the internet and found that no other survivor received useful information. This is an attempt to cover all stroke rehabilitation information that should be readily available to survivors so they can talk with informed knowledge to their medical staff. It lays out what needs to be done to get stroke survivors closer to 100% recovery. It's quite disgusting that this information is not available from every stroke association and doctors group.

Friday, October 14, 2011

Aspirin should not be used for stroke prevention in AF patients

Ask your doctor.
http://www.theheart.org/article/1292913.do?utm_campaign=newsletter&utm_medium=email&utm_source=20111014_TopStories_EN%3Cbr%20/%3E
More evidence that aspirin is neither safe nor effective for the prevention of stroke in AF patients has come from a new Danish registry study [1].

The study, published in the October 2011 issue of Thrombosis and Haemostasis, was conducted by a group led by Dr Jonas Bjerring Olesen (Copenhagen University Hospital Gentofte, Hellerup, Denmark).

Second author Dr Gregory Lip (University of Birmingham, UK) commented to heartwire: "Our study is the largest real-world cohort study ever published looking at the use of aspirin and oral anticoagulation in AF patients, and it clearly shows that the net clinical benefit for aspirin is not positive at any level of stroke risk. It is neither safe nor effective."

He explained that there is a perception that aspirin is a safer alternative to oral anticoagulation for stroke prevention in AF patients, but "now we know that this simply is not the case."

As background, Lip noted that a meta-analysis of randomized trials of aspirin in AF suggested a 19% reduction in stroke, with confidence limits that crossed zero, and many of the trials included less than 10% of patients screened. The suggested benefit in this meta-analysis was driven by only one positive trial (SPAF-1). "Since then, increasing data have suggested that aspirin may not be effective at preventing stroke in this situation and may not be any safer than warfarin either. Despite this, doctors have embraced aspirin," Lip said.

He said the results of the new Danish study were in line with the latest European Society of Cardiology (ESC) guidelines, which were updated last year. These advised against using aspirin for stroke prevention in any AF patients after a Japanese study showed no benefit in low-risk patients. "The ESC updated the guidelines based on this study. Now our study has provided more real-world data in support of this recommendation."

For the Danish study, the researchers estimated the risk of thromboembolism and bleeding in 146 000 AF patients by linking data from the Danish National Patient Registry (which documents all patient hospitalizations), the Danish Registry of Medicinal Product Statistics (which records all prescription medicines prescribed to individual patients), and the National Causes of Death Registry.

Warfarin effective for all but very lowest risk

Another important finding was that warfarin was associated with a net clinical benefit in all AF patients except those at the very lowest risk of stroke (CHA2DS2-VASc score of 0). "It is only in these very low-risk patients that the bleeding risk of warfarin outweighs the benefit," Lip stated.

He added that these data did not apply to the new generation of oral anticoagulants, as they are only now reaching the market and so were not included in this study. "It is possible that the new drugs may be beneficial in the very lowest-risk patients, but we don't have data on this yet. All we can say for now is that warfarin is not beneficial for this one group, but it is beneficial for all other AF patients."

Lip explained that the CHA₂DS₂-VASc score is more inclusive of stroke risk factors than the CHADS₂ score, and the two scores tend to be complementary. "If the CHADS₂ score is already known to be 2, for example, there is no need for a CHA₂DS₂-VASc score, because we know that patient needs to be on anticoagulation. But if the CHADS₂ score is 0, patients could still have some stroke risk factors, and then the CHA₂DS₂-VASc score should be used as well. A CHA₂DS₂-VASc score of 0 signifies a very low risk indeed of thromboembolism—about 0.78 per 100 person-years."

Most benefit of warfarin in those at highest bleeding risk

Another finding of note in the Danish study was that the net clinical benefit of warfarin was highest in those patients with the highest bleeding risk. Lip explained that this was because these patients usually have the highest stroke risk too, and the absolute benefit of warfarin on reducing stroke risk easily outweighs the bleeding hazard. "These are the very patients that many doctors are wary of giving warfarin to, and they may be using aspirin instead, but these are actually the patients who need warfarin (or one of the new oral anticoagulants) the most. Aspirin is not the answer for these patients.

"I can't say that no AF patient should be taking aspirin, because many such patients may have other indications such as having had a stent, but for patients with AF alone, an oral anticoagulant is best, and even in AF patients with stable vascular disease there is no requirement to add aspirin on top of warfarin," he said.

But he added that this study suggests that oral anticoagulants are vastly underused for stroke prevention in AF. "We are now getting better at managing warfarin, and we have a new generation of easier-to-use oral anticoagulants, so we must make sure that we are offering effective stroke prevention to all AF patients with one or more stroke risk factors," Lip urged.