A meta-analysis of intracranial hemorrhage in patients with brain tumors receiving therapeutic anticoagulation

Background: Venous thromboembolism commonly occurs in patients with brain tumors. Because of the high rate of spontaneous intracranial hemorrhage (ICH), the safety of therapeutic anticoagulation is commonly questioned. Objective: We performed a meta-analysis to evaluate whether therapeutic anticoagulation is associated with an increased risk of intracranial hemorrhage in patients with brain tumors. Patients/Methods: A systematic literature search strategy was conducted. Summary statistics for ICH were obtained by calculating the odds ratio using a random effects model and heterogeneity across studies was estimated by the I 2 statistic. Results: A total of nine retrospective cohort studies met the criteria for inclusion. The odds ratio (OR) for ICH in patients receiving therapeutic anticoagulation versus those who did not receive anticoagulation was 2.13 (95% confidence interval [CI], 1.00-4.56; I-2 = 46%). In studies evaluating anticoagulation in patients with brain metastases, there was no apparent increased risk of ICH (OR, 1.07; 95% CI, 0.61-1.88; I-2 = 0%). However, in patients with glioma there was an increase in risk of ICH associated with the administration of anticoagulation (OR, 3.75; 95% CI, 1.42-9.95; I-2 = 33%). Conclusions: The risk of ICH in patients with brain tumors receiving therapeutic anticoagulation depends on the diagnosis of primary or metastatic brain tumors. Although anticoagulation was not associated with an increased risk of ICH in the setting of brain metastasis, its use resulted in a greater than 3-fold increased risk of ICH in patients with glioma.