POST-NOAC: Portuguese observational study of intracranial hemorrhage on non-vitamin K antagonist oral anticoagulants.

Background There is a lower reported incidence of intracranial hemorrhage with non-vitamin K antagonist oral anticoagulants compared with vitamin K antagonist. However, the functional outcome and mortality of intracranial hemorrhage patients were not assessed. Aims To compare the outcome of vitamin K antagonists- and non-vitamin K antagonist oral anticoagulants-related intracranial hemorrhage. Methods We included consecutive patients with acute non-traumatic intracranial hemorrhage on oral anticoagulation therapy admitted between January 2013 and June 2015 at four university hospitals. Clinical and demographic data were obtained from individual medical records. Intracranial hemorrhage was classified as intracerebral, extra-axial, or multifocal using brain computed tomography. Three-month functional outcome was assessed using the modified Rankin Scale. Results Among 246 patients included, 24 (9.8%) were anticoagulated with a non-vitamin K antagonist oral anticoagulants and 222 (90.2%) with a vitamin K antagonists. Non-vitamin K antagonist oral anticoagulants patients were older (81.5 vs. 76 years, p = 0.048) and had intracerebral hemorrhage more often (83.3% vs. 63.1%, p = 0.048). We detected a non-significant trend for larger intracerebral hemorrhage volumes in vitamin K antagonists patients ( p = 0.368). Survival analysis adjusted for age, CHA2DS2VASc, HAS-BLED, and anticoagulation reversal revealed that non-vitamin K antagonist oral anticoagulants did not influence three-month mortality (hazard ratio (HR) = 0.83, 95% confidence interval (CI) = 0.39-1.80, p = 0.638). Multivariable ordinal regression for three-month functional outcome did not show a significant shift of modified Rankin Scale scores in non-vitamin K antagonist oral anticoagulants patients (odds ratio (OR) 1.26, 95%CI 0.55-2.87, p = 0.585). Conclusions We detected no significant differences in the three-month outcome between non-vitamin K antagonist oral anticoagulants- and vitamin K antagonists-associated intracranial hemorrhage, despite unavailability of non-vitamin K antagonist oral anticoagulants-specific reversal agents.