Influence of antithrombotics on the etiology of intracerebral hemorrhage

Background To determine the influence of antithrombotic use on the etiology of primary intracerebral hemorrhage (ICH). Methods We conducted a retrospective review of consecutive patients admitted with primary ICH from 2009 to 2012. Data recorded included age, history of hypertension, and use of antithrombotic medications. Imaging was reviewed to determine hemorrhage location and the presence and the location of any microhemorrhages. Etiologies were classified using a predetermined algorithm, which was based on existing literature. Results In total, 292 patients were included. Median age was 74 years (range, 18-101), and 52% were male (n = 151). Hemorrhage etiology was hypertension in 50.6% (n = 148), indeterminate in 29.5% (n = 86), and cerebral amyloid angiopathy (CAA) in 19.9% (n = 58). Most patients were on antithrombotics (61.3%, n = 179). Nearly half of the patients (49%) were 75 years of age or older, and the most common etiology in this group was hypertension (n = 77, 53%). There was a nonsignificant trend toward older age and CAA-ICH (median age, 77 years; interquartile range [IQR], 70-82 years) compared with other causes (median age, 74 years; IQR, 61-82 years; P =.07). There was no difference between CAA-ICH and other-cause ICH with respect to proportion of patients on antithrombotics in general (67% versus 60%; P =.367) or anticoagulants in particular (24% versus 25%; P = 1.000). Conclusions The most common ICH etiology in this study was hypertension, regardless of age. Our findings do not suggest that the higher occurrence of ICH in older patients or in patients with CAA-associated ICH is because of a higher frequency of anticoagulant use.