New cerebral microbleeds in ischemic stroke patients on warfarin treatment: Two-year follow-up

ObjectiveCerebral microbleeds (CMBs) are known to be indicative of bleeding-prone microangiopathy. Little is known about the significance of CMBs in anticoagulated patients. We determined the frequency of new CMBs in ischemic stroke patients who had been receiving warfarin treatment for 2 years.MethodsA total of 204 ischemic stroke patients on warfarin therapy for 2 years underwent a repeat MRI. We compared demographic features, vascular risk factors, and radiological findings of patients with and without new CMBs.ResultsNew CMBs on gradient-echo MRI were found in 29 of 204 patients (10%). Of 35 patients who had CMBs in the original study, 9 developed new CMBs after 2 years (26%), compared with 20 of the 169 patients (12%) who did not have CMBs at baseline (p = 0.03). Patients with new CMBs were older than patients without CMBs (p = 0.04), and the frequency of leukoaraiosis was significantly higher (p = 0.02). The mean duration of warfarin treatment was not significantly different between the patients with and without new CMBs (p = 0.28).ConclusionThis longitudinal study suggested that the presence of CMBs at baseline increased the frequency of new CMBs in patients on warfarin therapy.