Brain bleeds in patients on medication for atrial fibrillation – new study
People with atrial fibrillation can sometimes have a brain bleed due to the anticoagulant medication they use to reduce their risk of having a clot-type stroke.
A new study suggests these patients have similar outcomes from the brain bleed, whether they're on one of the new anticoagulant drugs (rivaroxaban, dabigatran, apixaban) or on a vitamin K antagonist drug (warfarin).
What are oral anti-coagulant drugs and why are they important?
Atrial Fibrilliation (AF) is an irregular heartbeat and the condition increases the risk of stroke by up to five times.
Oral anti-coagulant (OAC) medication can help reduce the risk of a clot forming in a the circulatory system and travelling to the brain to cause an (ischaemic) stroke. There are currently two types of OAC medication available: vitamin K antagonist medication (warfarin), and NOAC (Non-vitamin K Oral Anti-Coagulant) medication (including rivaroxaban, dabigatran, and apixaban).
Randomised trials have already shown that AF patients treated with NOACs can sometimes experience a type of bleeding stroke called an intracerebral haemorrhage (ICH), and that this is at about half the rate at which patients treated with vitamin K antagonist medication do. However, both NOACs and vitamin K antagonist medication was found to be similarly effective at preventing ischaemic (clot-type) strokes.
Despite the reduced rate of brain bleeds with NOAC medication, there remains concern about their overall safety and effectiveness as they are much newer drugs.
What did the new research show?
Published online first in the journal Neurology, a new study suggests that people with AF who have an ICH due to their medication have similar outcomes whether they're on a NOAC or a vitamin K antagonist drug.
The international study looked at the outcomes of 500 patients with AF who had an ICH related to their anticoagulant medication. Of these, 97 were on NOAC medication, and 403 were on vitamin K antagonist medication.
The study found that the size of the ICH, the expansion of clotted blood around the ICH, and the rate of death and the functional outcomes of patients 90 days after ICH, were similiar between those on NOAC medication and vitamin K antagonist medication.
This may have implications for clinical practice, as the treatments for NOAC related ICH are not as well developed and established as those for vitamin K antagonist related ICH. Some have previously raised concern that without as developed treatment for NOAC related ICH the outcomes could be more serious, which is not supported by the current study.
Who funded the study?
The study was co-funded by the Stroke Association and the British Heart Foundation (TSA BHF 2009-01) among other funders.
Who led the study?
Professor David Werring, University College London (UCL), led on the study and is Chief Investigator of the wider CROMIS-2 trial, which was supported by the NIHR Clinical Research Network.