Mortality and functional outcomes in patients with anticoagulant-related intracerebral hemorrhage (ICH) do not appear to be associated with the type of oral anticoagulants used, according to an international group of researchers.

In patients with atrial fibrillation, use of vitamin K antagonist (VKA) oral anticoagulants is associated with twice the incidence of ICH seen with non-vitamin K oral antagonists (NOACS), Dr. David J. Werring of University College London and colleagues note in Neurology. Both types of agents are similarly efficacious in preventing ischemic stroke, they add.

However, although several strategies have been developed for VKA reversal, this is not the case for NOACs. Thus NOAC-associated ICH might be larger, with a higher risk of hematoma expansion and worse outcome, the researchers hypothesized.

To investigate, they conducted an international pooled analysis involving 500 patients who had ICH while on oral anticoagulation. Patients with a secondary cause for ICH, such as major head trauma or vascular malformations, were excluded. In total 97 patients received NOACs and 403 got VKAs. Overall, 161 patients had died by 90 days, giving a crude mortality rate of 32 percent. There was no difference for all-cause 90-day mortality between the NOAC group (33 percent) and the VKA patients (31 percent). There also was no between-group difference in 30-day or 60-day mortality. The same was true of the rate of hematoma expansion (40 percent vs. 34 percent, P=0.45).

Good functional outcome defined as a discharge modified Rankin Scale score of 2 or less also did not differ significantly between groups. Although in univariable analysis the VKA group appeared to be more likely to be functionally independent at discharge (23 percent vs. 10 percent, P<0.001) this was not the case after adjustment and multivariable analysis. However, the researchers caution, "We do not know how widely NOAC adoption was within each source population, which could lead to confounding by indication." While recommending further study, they note that the findings do not support previous concerns about NOACs. "These results, together with previous observational and trial data, should help to reassure clinicians that NOAC-ICH does not seem to have worse outcome than VKA-ICH, despite the current limited access to specific NOAC reversal agents," Dr. Werring told Reuters Health by email. Dr. Christian T. Ruff, a specialist in cardiovascular medicine at Brigham and Women's Hospital in Boston, said, "This research highlights that sobering reality that anticoagulation-associated intracranial hemorrhages are devastating, regardless of agent. The main advantage of NOACs compared with warfarin and other vitamin K antagonists is that they cause half as many intracranial hemorrhages, even without a specific reversal agent."

“While ‘reversal’ of warfarin with vitamin K and clotting factors does not seem to offer much benefit once a patient suffers an intracranial hemorrhage, there is continued optimism that rapid and highly effective antidotes to the NOACs may improve outcomes in these patients,” Dr. Ruff, who was not involved in the study, told Reuters Health by email.

The study had no commercial funding. Some of the authors reported ties to drug companies selling NOACs.