Cerebral Microbleeds and the Safety of Anticoagulation in Ischemic Stroke Patients: A Systematic Review and Meta-Analysis

Objectives The objective of this study was to investigate the safety of anticoagulation in ischemic stroke (IS) patients with cerebral microbleeds (CMBs). Methods PubMed, Web of Science, Elsevier Clinical Key, Google Scholar, and Cochrane Library from 1996 to July 2018 were searched to identify relevant studies that included IS patients, underwent T2*-weighted gradient recalled echo, or susceptibility-weighted imaging for detection CMBs and used anticoagulants during follow-up. Primary outcome of interest was intracerebral hemorrhage (ICH). Secondary outcomes were hemorrhage transformation, IS, total mortality, and new developed CMBs. We critically appraised studies and conducted a systematic review and meta-analysis following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidance. Results We included 7 observational studies. Cerebral microbleeds were associated with a significantly elevated risk of anticoagulation-related ICH (odds ratio, 4.01; 95% confidence interval, 1.82-8.81; P = 0.001). It was significant for warfarin (odds ratio, 8.02; 95% confidence interval, 1.51-42.62; P = 0.015). New developed CMBs in patients on warfarin treatment were associated with baseline CMBs, and the appearance of hemorrhagic transformation did not have a significant relationship with baseline CMBs. Conclusions The presence of CMBs increases the risk of ICH during anticoagulant treatment (especially warfarin) in IS patients. Further studies with larger numbers of patients are needed to confirm our conclusions.