Use of Antithrombotic Drugs and the Presence of Cerebral Microbleeds The Rotterdam Scan Study

Background: Cerebral microbleeds are hemosiderin deposits in the brain that are indicative of microangiopathy. Microbleeds in strictly lobar brain locations have been related to cerebral amyloid angiopathy, a bleeding-prone disease state. Objective: To investigate the relation between antithrombotic drug use and the presence of cerebral microbleeds, especially those in strictly lobar locations. Design: A population-based, cross-sectional analysis that used magnetic resonance imaging (MRI) to assess the presence and location of microbleeds. Complete information on outpatient use of platelet aggregation inhibitors and anticoagulant drugs before MRI was obtained from automated pharmacy records. Setting: The Rotterdam Scan Study, a population-based imaging study in a general elderly community in the Netherlands. Participants: A population-based sample of 1062 persons from a longitudinal cohort, 60 years and older, free of dementia, who underwent MRI examinations between August 15, 2005, and November 22, 2006. Main Outcome Measures: Presence of cerebral microbleeds on MRI. Results: Compared with nonusers of antithrombotic drugs, cerebral microbleeds were more prevalent among users of platelet aggregation inhibitors (adjusted odds ratio [OR], 1.71; 95% confidence interval [CI], 1.21-2.41). We did not find a significant association for anticoagulant drugs and microbleed presence (OR, 1.49; 95% CI, 0.82-2.71). Strictly lobar microbleeds were more prevalent among aspirin users (adjusted OR compared with nonusers, 2.70; 95% CI, 1.45-5.04) than among persons using carbasalate calcium (adjusted OR, 1.16; 95% CI, 0.66-2.02). This difference was even more pronounced when comparing persons who had used similar dosages of both drugs. Conclusions: This cross-sectional study shows that use of platelet aggregation inhibitors is related to the presence of cerebral microbleeds. Furthermore, aspirin and carbasalate calcium use may differently relate to the presence of strictly lobar microbleeds. Arch Neurol. 2009;66(6):714-720