Vitamin K Antagonists―Associated Cerebral Hemorrhages: What Are Their Characteristics?

The high prevalence of atrial fibrillation in aging populations leads to an increasing incidence of vitamin K antagonists-associated intracerebral hemorrhages (VKAs-ICH). It remains unclear whether VKAs are causes or risk factors for ICH. We aimed at identifying the specificities of VKAs-ICH. We compared baseline characteristics of 545 consecutive patients receiving or not receiving VKAs before admission for spontaneous ICH. To determine whether the influence of VKAs depends on the underlying vasculopathy, that is, cerebral amyloid angiopathy in lobar, and deep perforating arteries vasculopathy in deep ICH, we compared characteristics of ICH (including volume) according to the anatomic distribution of ICH in multiple linear regression. VKAs-ICH accounted for 83 patients, that is, 15% (95% confidence intervals, 12-18) of ICH in our cohort. The use of VKAs did not influence anatomic distribution of ICH. The impact of VKAs on ICH volume differed according to ICH location: in nonlobar ICH, VKAs use was associated with significant larger ICH volumes (median volume 25 mL vs 12 mL; P=0.002). In lobar ICH, VKAs use did not influence the volume (median 26 mL vs 30 mL; P=0.507). A similar anatomic distribution of ICH in patients with or without VKAs suggests that VKAs should not be considered as a cause of ICH because both locations are usually due to different vasculopathies (deep perforating arteries vasculopathy in deep and cerebral amyloid angiopathy in lobar). The different impact of VKAs on ICH volumes according to location suggests a different susceptibility of these vasculopathies to VKAs. This finding may lead to specific therapeutic strategies.