Novel oral anticoagulants (NOACs) may be the best defense against intracranial hemorrhage (ICH) when used to prevent strokes in patients with atrial fibrillation (AF), based on the findings of a meta-analysis published in the December issue of JAMA Neurology.

The investigators, led by Saurav Chatterjee, MD, of Brown University in Providence, R.I., analyzed six studies with more than 57,000 participants to evaluate how effectively NOACs prevent ICH. They looked at research that assessed dabigratran (Pradaxa, Boehringer Ingelheim), rivaroxaban (Xarelto, Janssen) and apixaban (Eliquis, Bristol-Myers Squibb), the three NOACs currently FDA approved for stroke prevention in patients with AF. The primary outcomes were ICH occurrences associated with each NOAC.

Their analysis found that the NOACs significantly lowered the risk of ICH compared with warfarin and aspirin (odds ratio 0.49) and also that the NOACs did not significantly differ from each other. Absolute ICH risk was 0.52 percent for dabigatran, 0.78 percent for rivaroxaban and 0.52 percent for apixaban compared with 1.24 percent for warfarin. The lower dose of dabigatran, which is not approved in the U.S. for stroke prevention in AF patients, was comparable to aspirin in terms of bleeding rates (0.45 percent for dabigatran vs. 0.46 percent for aspirin).

The mechanism explaining why the NOACs are more effective than warfarin at preventing ICH is unclear, although the authors hypothesized it could be because NOACs act on a single site in the clotting cascade rather than multiple sites.

They added that their findings have clinical implications, suggesting that NOACs “should be considered first line for patients at high risk for ICH without any credible differences among the individual agents.”